// Static file server + same-origin proxy to the fal.ai queue API.
// ponytail: keeping the proxy (rather than calling queue.fal.run directly
// from the browser) sidesteps having to verify fal's CORS behavior at all —
// same trick used for the MiniMax-native integration this replaced.
const http = require("http");
const https = require("https");
const fs = require("fs");
const path = require("path");
const os = require("os");
const crypto = require("crypto");
const { execFileSync } = require("child_process");

try {
  process.loadEnvFile(path.join(__dirname, ".env"));
} catch {
  // no .env file — fine, env vars may be set another way
}

const PORT = process.env.PORT || 8934;
const FAL_HOST = "queue.fal.run";
const H3_CONSOLE_BASE = process.env.H3_CONSOLE_BASE || "";
const H3_CONSOLE_TOKEN = process.env.H3_CONSOLE_TOKEN || "";
const H3_CONSOLE_URL = H3_CONSOLE_BASE ? new URL(H3_CONSOLE_BASE) : null;

// GLM Coding Plan — used only to expand a viewer's short chat prompt into a
// detailed shot-by-shot prompt before handing it to H3 (see optimizePrompt).
// Must hit the /api/coding/ path specifically — the plain /api/paas/ path
// bills against a different (pay-per-token) quota than the coding plan.
const GLM_API_KEY = process.env.GLM_API_KEY || "";
const GLM_HOST = "open.bigmodel.cn";
const GLM_PATH = "/api/coding/paas/v4/chat/completions";
const GLM_MODEL = "glm-5.3-flash";

// T24 credit topup. No test-mode key yet (2026-09-03: user said "先做一个
// mock，我明天再给你真实测试的 key") — see createCheckoutSession()'s doc
// comment for how the two paths split.
const STRIPE_SECRET_KEY = process.env.STRIPE_SECRET_KEY || "";
const STRIPE_WEBHOOK_SECRET = process.env.STRIPE_WEBHOOK_SECRET || "";
const APP_BASE_URL = process.env.APP_BASE_URL || `http://localhost:${process.env.PORT || 8934}`;

// T33 (dev-plan-5.md): fal.ai real-time compute for paid requests (需求文档
// 4.3 节双算力策略) — no key configured yet, same situation T24 was in with
// Stripe. See generateDanceVideoViaFal()'s doc comment for what's verified
// vs. still unverified (§8 item 1 / dev-plan-5.md §1.2 item 3: whether the
// one-step attribute_transfer prompt that works on H3 Console also works on
// fal's model — that needs a real call, not something code can assert).
const FAL_API_KEY = process.env.FAL_API_KEY || "";
// Overridable so tests can point these at a local mock (same reasoning as
// H3_CONSOLE_BASE) — default to fal's real, documented hosts.
const FAL_REST_BASE = process.env.FAL_REST_BASE || "https://rest.alpha.fal.ai";
const FAL_QUEUE_BASE = process.env.FAL_QUEUE_BASE || "https://queue.fal.run";
const FAL_MODEL_ID = "minimax/h3/reference-to-video";

// Standalone "人衣图生成" admin tool (admin-dressgen.html) — person 3-views +
// garment -> composite portrait via gpt-image-2, hosted behind 万界方舟's
// maas-openapi relay. NOT the same pipeline as generateDanceVideoViaFal
// above (that's H3/fal video); this is a one-shot image edit call.
//
// Contract confirmed against a real curl example the user supplied for the
// sibling /images/generations endpoint on this same host, plus this
// environment's own OPTIONS/GET probing of /images/edits (2026-09-03):
//   - host+path is maas-openapi.wanjiedata.com/api/v1/images/edits, NOT
//     fangzhou.wanjiedata.com/v1/images/edits (that first guess 405'd —
//     wrong host *and* wrong path; fangzhou is the docs/dashboard SPA, not
//     the API gateway. GET on the real /images/edits path 405s with an
//     explicit `Allow: POST` header from APISIX, confirming it's a real
//     registered route, not the SPA's catch-all).
//   - model id is the literal string "GPT Image 2" (with spaces) — the user
//     was warned a typo here gets WAF-blocked with 410 or "model
//     unauthorized", so don't "clean up" this string.
//   - this host's TLS chain does not validate from this machine (confirmed:
//     the user's own working curl needs -k) — generateDressImage() below
//     sends the request via a raw https.request with rejectUnauthorized
//     false scoped to just this one call, not a process-wide
//     NODE_TLS_REJECT_UNAUTHORIZED=0 (that would silently weaken every
//     other HTTPS call this server makes — Stripe, GLM, H3 Console, fal.ai).
//   - the /generations sibling responds JSON {data:[{url}]} (a short-lived
//     presigned URL, must be fetched immediately) and takes size/n as
//     top-level fields, not response_format (explicitly unsupported — don't
//     send it). /images/edits itself has NOT been call-tested (no example
//     for it specifically was available, only /generations + this
//     environment's unauthenticated OPTIONS/GET probing of the route's
//     existence) — its multipart shape here (image[] repeated, prompt,
//     model, size, n) mirrors OpenAI's own public /v1/images/edits
//     contract, which the user confirmed this vendor keeps in lockstep
//     with. First real authenticated call is still the actual proof.
//   - a real edit call takes 60-180s; the timeout must allow for 300s+.
const IMAGE2_API_KEY = process.env.IMAGE2_API_KEY || "";
const IMAGE2_API_BASE = process.env.IMAGE2_API_BASE || "https://maas-openapi.wanjiedata.com";
const IMAGE2_EDIT_PATH = "/api/v1/images/edits";
const IMAGE2_MODEL = "GPT Image 2";
const IMAGE2_SIZE = "1024x1536"; // within the ~157万-pixel cap the user measured; anything larger is silently downscaled
const IMAGE2_TIMEOUT_MS = 300000;
const IMAGE2_MIME = { png: "image/png", jpg: "image/jpeg", jpeg: "image/jpeg", webp: "image/webp" };

// Second dressgen provider (2026-09-03) — admin-picked per task
// (record.provider) via the UI, or picked automatically as a fallback (see
// below).
//
// UPDATE (2026-09-03, later same day): the paragraph above originally said
// this would never auto-fallback on an IMAGE2 failure, reasoning that it'd
// silently re-route content around whichever provider's own moderation
// rejected it first. Asked directly about that tradeoff — with the
// concrete case in hand (a real-person-photo + swimwear task whose IMAGE2
// 400 looked like a moderation rejection, not a technical fault) — the
// product call came back "any failure auto-switches", overriding that
// stance. See runDressGenViews' fallback branch below. Recorded here so
// the next session doesn't rediscover this as a bug.
//
// Contract confirmed 2026-09-03 via real calls (not guessed): upload each
// image with POST {base}/api/v3/media/upload/binary (multipart, field
// "file") -> {data.download_url}; submit with POST {base}/api/v3/{model}
// (JSON: {prompt, images:[url,...]}) -> {data.id, data.urls.get}; poll
// data.urls.get until status is "completed" (-> data.outputs[0] is the
// result URL) or "failed" (-> data.error). No TLS quirks here (unlike
// IMAGE2) — plain fetch works.
const WAVESPEED_API_KEY = process.env.WAVESPEED_API_KEY || "";
const WAVESPEED_API_BASE = process.env.WAVESPEED_API_BASE || "https://api.wavespeed.ai";
const WAVESPEED_MODEL = "bytedance/seedream-v4/edit";
const WAVESPEED_POLL_INTERVAL_MS = Number(process.env.WAVESPEED_POLL_INTERVAL_MS) || 3000;
const WAVESPEED_TIMEOUT_MS = 180000; // observed ~30s in practice; generous headroom over that

const DRESSGEN_PROVIDERS = ["image2", "wavespeed"];
const DRESSGEN_DEFAULT_PROVIDER = "image2";

function dressGenProviderKeyMissing(provider) {
  if (provider === "wavespeed") return !WAVESPEED_API_KEY ? "WAVESPEED_API_KEY not configured" : null;
  return !IMAGE2_API_KEY ? "IMAGE2_API_KEY not configured" : null;
}

// Raw https.request wrapper (not fetch) so rejectUnauthorized:false can be
// scoped to exactly this one call — see the doc comment above. bodyBuffer
// may be omitted for a plain GET-style fetch (used for the presigned result
// URL, which may or may not share 万界's own broken cert chain — safer to
// go through the same relaxed path than to assume it doesn't). Dispatches
// on the URL's own protocol (not hardcoded to https) purely so tests can
// point IMAGE2_API_BASE at a plain-http local mock; the real vendor is
// always https.
function insecureHttpsRequest(urlString, { method = "GET", headers = {}, bodyBuffer } = {}) {
  return new Promise((resolve, reject) => {
    const url = new URL(urlString);
    const transport = url.protocol === "http:" ? http : https;
    const req = transport.request(
      {
        hostname: url.hostname,
        port: url.port || (url.protocol === "http:" ? 80 : 443),
        path: `${url.pathname}${url.search}`,
        method,
        rejectUnauthorized: false,
        headers,
        timeout: IMAGE2_TIMEOUT_MS,
      },
      (res) => {
        const chunks = [];
        res.on("data", (c) => chunks.push(c));
        res.on("end", () => resolve({ status: res.statusCode, buffer: Buffer.concat(chunks) }));
      }
    );
    req.on("timeout", () => req.destroy(new Error(`image2 request timed out after ${IMAGE2_TIMEOUT_MS}ms`)));
    req.on("error", reject);
    if (bodyBuffer) req.write(bodyBuffer);
    req.end();
  });
}

// 人物参考图最多 6 张定妆照（全身/脸部 × 正/侧/背），但不强制全传——传几张
// 算几张（至少 1 张）。gpt-image-2 的 edit 端点没有"生成 3 张不同视角"的原生
// 能力（同一次调用的 n 个输出是同一编辑的独立采样，不是可寻址的不同机位，
// CODEX-IMAGEGEN.md §4.3 也确认 edit 没有 batch 子命令），所以三个目标视角
// 分三次独立调用；每次调用都把用户实际上传的全部人物参考图 + 新衣服图一起
// 喂进去（不按 slot 精确配对），靠 prompt 里的目标视角文字区分三次调用要出
// 哪个角度。三次调用按顺序（依次）发起，不并发。
const DRESSGEN_PERSON_SLOTS = ["bodyFront", "bodySide", "bodyBack", "faceFront", "faceSide", "faceBack"];
const DRESSGEN_VIEWS = ["front", "side", "back"];
const DRESSGEN_VIEW_LABEL = { front: "正面", side: "侧面", back: "背面" };

function defaultDressgenPrompt(view) {
  const label = DRESSGEN_VIEW_LABEL[view];
  return (
    "前面的图是同一位人物的参考图（可能包含全身正/侧/背、脸正/侧/背等不同角度和部位，具体张数以实际上传为准），最后一张图是新服装参考图。" +
    `保持人物的脸部五官、发型、体型完全不变，仅将服装替换为新服装图所示服装，生成人物穿着新服装的${label}全身人物形象图。` +
    "鞋子沿用人物原有款式，不要更换；背景、地面材质、光照方向和色调都必须跟人物参考图里的场景保持一致——" +
    "不要换成纯色影棚背景，也不要换成另一个场景，三个视角（正/侧/背）用的是同一个背景。全身入镜。Size 1024x1536."
  );
}

// Runs (a subset of) DRESSGEN_VIEWS' edit calls in sequence against an
// already-created dressGenRecords row, writing progress back after every
// single view so admin-dressgen.html's poll (GET /api/admin/dressgen) can
// show "queued/generating/done/failed" per view while it's still running —
// not just a final result once the whole thing settles. Called
// fire-and-forget (`.catch(() => {})` at the call site) right after the
// HTTP response for POST /dressgen or POST /dressgen/:id/retry has already
// gone out; every failure mode here is recorded on the row itself, not
// thrown back to a caller that's no longer listening. `views` lets retry
// reprocess only the views that didn't succeed last time, without touching
// ones that already have an output.
async function runDressGenViews(recordId, imageAbsPaths, views) {
  for (const view of views) {
    const before = dressGenRecords.get(recordId);
    if (!before) return; // row was deleted mid-flight
    dressGenRecords.update(recordId, { viewStatus: { ...before.viewStatus, [view]: "generating" } });
    const provider = before.provider || DRESSGEN_DEFAULT_PROVIDER;
    let usedProvider = provider;
    try {
      let imageBuffer;
      try {
        imageBuffer = await generateDressImage({ imageAbsPaths, prompt: before.prompts[view], provider });
      } catch (err) {
        // Automatic fallback: default provider (image2) failed for any
        // reason -> retry once via wavespeed before giving up on this view.
        // See the note above generateDressImage's declaration for why.
        if (provider === DRESSGEN_DEFAULT_PROVIDER && !dressGenProviderKeyMissing("wavespeed")) {
          usedProvider = "wavespeed";
          imageBuffer = await generateDressImage({ imageAbsPaths, prompt: before.prompts[view], provider: "wavespeed" });
        } else {
          throw err;
        }
      }
      const { relPath } = placeInUploads(imageBuffer, "png");
      const after = dressGenRecords.get(recordId);
      if (!after) return;
      dressGenRecords.update(recordId, {
        outputImages: { ...after.outputImages, [view]: relPath },
        errors: { ...after.errors, [view]: null },
        viewStatus: { ...after.viewStatus, [view]: "done" },
        viewProvider: { ...(after.viewProvider || {}), [view]: usedProvider },
      });
    } catch (err) {
      const after = dressGenRecords.get(recordId);
      if (!after) return;
      dressGenRecords.update(recordId, {
        errors: { ...after.errors, [view]: err.message },
        viewStatus: { ...after.viewStatus, [view]: "failed" },
      });
    }
  }
  const final = dressGenRecords.get(recordId);
  if (!final) return;
  const succeeded = DRESSGEN_VIEWS.filter((v) => final.outputImages[v]).length;
  const status = succeeded === DRESSGEN_VIEWS.length ? "done" : succeeded > 0 ? "partial" : "failed";
  dressGenRecords.update(recordId, { status });
}

// Startup recovery, same idea as resumeDressupGenerations() above: a
// record can be sitting in "generating" if the process died mid-view.
// Unlike generationJobs there's no in-flight request id to reconnect to
// (image2/wavespeed calls are plain awaited HTTP round-trips inside
// runDressGenViews, nothing survives the process exiting) — every
// "queued"/"generating" view is unrecoverable, so it's marked failed with
// a distinguishable error, same as a real generation failure would be, and
// is one click to retry from either list or detail page.
function resumeDressgenTasks() {
  for (const record of dressGenRecords.list()) {
    const staleViews = DRESSGEN_VIEWS.filter((v) => record.viewStatus[v] === "queued" || record.viewStatus[v] === "generating");
    if (staleViews.length === 0) continue;
    const viewStatus = { ...record.viewStatus };
    const errors = { ...record.errors };
    for (const v of staleViews) {
      viewStatus[v] = "failed";
      errors[v] = "进程重启，任务丢失，请点重试";
    }
    const succeeded = DRESSGEN_VIEWS.filter((v) => record.outputImages[v]).length;
    const status = succeeded === DRESSGEN_VIEWS.length ? "done" : succeeded > 0 ? "partial" : "failed";
    dressGenRecords.update(record.id, { viewStatus, errors, status });
  }
}

// imageAbsPaths for a dressGenRecords row, recomputed from its own stored
// fields — used both at creation time and by retry (which reuses the
// original upload, no re-selecting images).
function dressGenImageAbsPaths(record) {
  const personPaths = DRESSGEN_PERSON_SLOTS.filter((f) => record[f]).map((f) => record[f]);
  return [...personPaths, record.garmentImage].map((p) => path.join(__dirname, p));
}

async function generateDressImage({ imageAbsPaths, prompt, provider }) {
  return provider === "wavespeed" ? generateDressImageViaWavespeed({ imageAbsPaths, prompt }) : generateDressImageViaImage2({ imageAbsPaths, prompt });
}

async function generateDressImageViaImage2({ imageAbsPaths, prompt }) {
  if (!IMAGE2_API_KEY) throw new Error("IMAGE2_API_KEY not configured");
  const form = new FormData();
  form.set("model", IMAGE2_MODEL);
  form.set("prompt", prompt);
  form.set("n", "1");
  form.set("size", IMAGE2_SIZE);
  for (const absPath of imageAbsPaths) {
    const ext = path.extname(absPath).slice(1).toLowerCase();
    form.append("image[]", new Blob([fs.readFileSync(absPath)], { type: IMAGE2_MIME[ext] || "application/octet-stream" }), path.basename(absPath));
  }
  // Encode via the platform's own FormData/Response to get correct
  // multipart boundary handling for free, then send over insecureHttpsRequest
  // (not fetch) — see IMAGE2_API_KEY's doc comment for why.
  const encoded = new Response(form);
  const contentType = encoded.headers.get("content-type");
  const bodyBuffer = Buffer.from(await encoded.arrayBuffer());

  const { status, buffer } = await insecureHttpsRequest(`${IMAGE2_API_BASE}${IMAGE2_EDIT_PATH}`, {
    method: "POST",
    headers: { Authorization: `Bearer ${IMAGE2_API_KEY}`, "Content-Type": contentType, "Content-Length": bodyBuffer.length },
    bodyBuffer,
  });
  const text = buffer.toString("utf8");
  if (status < 200 || status >= 300) throw new Error(`image2 edit failed: ${status} ${text.slice(0, 500)}`);
  let json;
  try {
    json = JSON.parse(text);
  } catch {
    throw new Error(`image2 edit returned non-JSON response: ${text.slice(0, 500)}`);
  }
  const item = json.data && json.data[0];
  if (!item) throw new Error("image2 edit response missing data[0]");
  if (item.b64_json) return Buffer.from(item.b64_json, "base64");
  if (item.url) {
    const { status: imgStatus, buffer: imgBuffer } = await insecureHttpsRequest(item.url);
    if (imgStatus < 200 || imgStatus >= 300) throw new Error(`failed to fetch generated image: ${imgStatus}`);
    return imgBuffer;
  }
  throw new Error("image2 edit response missing b64_json/url");
}

async function wavespeedUpload(absPath) {
  const ext = path.extname(absPath).slice(1).toLowerCase();
  const form = new FormData();
  form.set("file", new Blob([fs.readFileSync(absPath)], { type: IMAGE2_MIME[ext] || "application/octet-stream" }), path.basename(absPath));
  const res = await fetch(`${WAVESPEED_API_BASE}/api/v3/media/upload/binary`, {
    method: "POST",
    headers: { Authorization: `Bearer ${WAVESPEED_API_KEY}` },
    body: form,
  });
  const json = await res.json();
  if (!res.ok || !json.data || !json.data.download_url) throw new Error(`wavespeed upload failed: ${res.status} ${JSON.stringify(json).slice(0, 500)}`);
  return json.data.download_url;
}

async function generateDressImageViaWavespeed({ imageAbsPaths, prompt }) {
  if (!WAVESPEED_API_KEY) throw new Error("WAVESPEED_API_KEY not configured");
  const imageUrls = [];
  for (const absPath of imageAbsPaths) imageUrls.push(await wavespeedUpload(absPath));

  const submitRes = await fetch(`${WAVESPEED_API_BASE}/api/v3/${WAVESPEED_MODEL}`, {
    method: "POST",
    headers: { Authorization: `Bearer ${WAVESPEED_API_KEY}`, "Content-Type": "application/json" },
    body: JSON.stringify({ prompt, images: imageUrls }),
  });
  const submitJson = await submitRes.json();
  if (!submitRes.ok || !submitJson.data || !submitJson.data.urls || !submitJson.data.urls.get) {
    throw new Error(`wavespeed submit failed: ${submitRes.status} ${JSON.stringify(submitJson).slice(0, 500)}`);
  }
  const resultUrl = submitJson.data.urls.get;

  const deadline = Date.now() + WAVESPEED_TIMEOUT_MS;
  while (Date.now() < deadline) {
    await new Promise((r) => setTimeout(r, WAVESPEED_POLL_INTERVAL_MS));
    const pollRes = await fetch(resultUrl, { headers: { Authorization: `Bearer ${WAVESPEED_API_KEY}` } });
    const pollJson = await pollRes.json();
    const status = pollJson.data && pollJson.data.status;
    if (status === "completed") {
      const outputUrl = pollJson.data.outputs && pollJson.data.outputs[0];
      if (!outputUrl) throw new Error("wavespeed result completed but has no outputs[0]");
      const imgRes = await fetch(outputUrl);
      if (!imgRes.ok) throw new Error(`failed to fetch wavespeed output: ${imgRes.status}`);
      return Buffer.from(await imgRes.arrayBuffer());
    }
    if (status === "failed") throw new Error(`wavespeed generation failed: ${pollJson.data.error || "unknown error"}`);
    // otherwise still "created"/"processing" — keep polling
  }
  throw new Error(`wavespeed generation timed out after ${WAVESPEED_TIMEOUT_MS}ms`);
}

const MIME = {
  ".html": "text/html",
  ".js": "text/javascript",
  ".css": "text/css",
  ".json": "application/json",
  ".jpg": "image/jpeg",
  ".jpeg": "image/jpeg",
  ".png": "image/png",
  ".webp": "image/webp",
  ".mp4": "video/mp4",
};

const { syncLibrary } = require("./ingest.js");
const {
  UPLOADS_DIR,
  readRawBody,
  parseMultipart,
  boundaryFromContentType,
  sniffImageType,
  sniffVideoType,
  stripMetadataAndSave,
  saveVideoUpload,
  placeInUploads,
  forwardToH3Assets,
  forwardToFalAssets,
} = require("./uploads.js");
const { characters, garments, danceRefs, characterImages, generationJobs, moderationLog, blacklist, dressGenRecords } = require("./dressup-store.js");
const { buildStage2Prompt } = require("./prompt-template.js");
const { users: userStore, sessions: userSessions, creditLedger } = require("./db.js");
const { pricing } = require("./pricing.js");

const LIBRARY_PATH = path.join(__dirname, "library.json");
function getLibrary() {
  try {
    return JSON.parse(fs.readFileSync(LIBRARY_PATH, "utf8"));
  } catch {
    return [];
  }
}
function saveLibrary(lib) {
  fs.writeFileSync(LIBRARY_PATH, JSON.stringify(lib, null, 2));
}

// One-time backfill (2026-09 上架/下架): clips already QC'd "correct" before
// `published` existed count as already having passed verification, so they
// stay live in dance.html's random-fill pool instead of the room going
// quiet until someone re-publishes 57+ clips by hand.
(function backfillPublished() {
  const lib = getLibrary();
  let changed = false;
  for (const c of lib) {
    if (c.channel === "dance" && c.published === undefined) {
      c.published = c.qcStatus === "correct";
      changed = true;
    }
  }
  if (changed) saveLibrary(lib);
})();

const LIVE_STATE_PATH = path.join(__dirname, "live-state.json");
function loadLiveState() {
  try {
    const s = JSON.parse(fs.readFileSync(LIVE_STATE_PATH, "utf8"));
    return { schedule: s.schedule || [], promptQueue: s.promptQueue || [], chatMessages: s.chatMessages || [] };
  } catch {
    return { schedule: [], promptQueue: [], chatMessages: [] };
  }
}
function saveLiveState() {
  fs.writeFileSync(LIVE_STATE_PATH, JSON.stringify({ schedule, promptQueue, chatMessages }, null, 2));
}

// dance.html's own playout state (T11) — separate file/schedule/queue from
// live.html's (architecture.md 2.1: two independent channels, not shared).
// Per MVCP M.8, `schedule` here stores `videoId` references, not inlined
// clip snapshots like live's `schedule` does — dance clips join back to
// library.json at read time so an admin edit/takedown isn't stuck showing a
// stale copy.
//
// One live room per character (人物库多直播间, 2026-09): schedule/queue/
// priorityInbox used to be single global arrays (one shared room, always
// the one characters.isDefault character). They're now keyed by characterId
// — `danceRooms[characterId] = { schedule, queue, priorityInbox }` — a room
// exists for every character that has at least one channel:"dance" clip
// (getDanceRoomCharacterIds below), created lazily on first tick/request.
const DANCE_STATE_PATH = path.join(__dirname, "dance-state.json");
function loadDanceState() {
  try {
    const s = JSON.parse(fs.readFileSync(DANCE_STATE_PATH, "utf8"));
    if (s.rooms) return { danceRooms: s.rooms };
    // Pre-multi-room save file: migrate the one flat room forward onto
    // whichever character it actually belonged to (characters.isDefault),
    // rather than silently dropping in-flight generations/queued picks.
    const defaultCharacter = characters.list().find((c) => c.isDefault);
    const hadState = (s.schedule || []).length || (s.freeQueue || []).length || (s.priorityInbox || []).length;
    if (defaultCharacter && hadState) {
      return { danceRooms: { [defaultCharacter.id]: { schedule: s.schedule || [], queue: s.freeQueue || [], priorityInbox: s.priorityInbox || [] } } };
    }
    return { danceRooms: {} };
  } catch {
    return { danceRooms: {} };
  }
}
function saveDanceState() {
  fs.writeFileSync(DANCE_STATE_PATH, JSON.stringify({ rooms: danceRooms }, null, 2));
}
function getDanceRoom(characterId) {
  if (!danceRooms[characterId]) danceRooms[characterId] = { schedule: [], queue: [], priorityInbox: [] };
  return danceRooms[characterId];
}
// Every character with >=1 generated dance video gets a room automatically
// — no separate "publish/go-live" toggle (confirmed: "有视频就自动开间").
function getDanceRoomCharacterIds() {
  const ids = new Set(Object.keys(danceRooms));
  for (const clip of getLibrary()) if (clip.channel === "dance" && clip.characterId && clip.qcStatus !== "incorrect") ids.add(clip.characterId);
  return ids;
}
function getRoomViewers(characterId) {
  if (!danceViewers.has(characterId)) danceViewers.set(characterId, new Map());
  return danceViewers.get(characterId);
}

function readJsonBody(req) {
  return new Promise((resolve, reject) => {
    let data = "";
    req.on("data", (chunk) => (data += chunk));
    req.on("end", () => {
      try {
        resolve(data ? JSON.parse(data) : {});
      } catch (err) {
        reject(err);
      }
    });
    req.on("error", reject);
  });
}

// Stripe's webhook signature is computed over the exact raw request bytes
// (T24) — JSON.parse-then-restringify would not reproduce the same bytes,
// so this can't reuse readJsonBody for that one route.
function readRawTextBody(req) {
  return new Promise((resolve, reject) => {
    let data = "";
    req.on("data", (chunk) => (data += chunk));
    req.on("end", () => resolve(data));
    req.on("error", reject);
  });
}

// Minimal admin auth (dev-plan.md T6): one shared password from .env, an
// HttpOnly session cookie, no accounts/roles/DB — the account system in
// MVCP M.1/M.10 supersedes this in period 3. Sessions are in-memory only,
// so a process restart logs everyone out (acceptable for this stopgap).
const ADMIN_PASSWORD = process.env.ADMIN_PASSWORD || "";
const ADMIN_SESSION_COOKIE = "admin_session";
const ADMIN_SESSION_TTL_MS = 30 * 24 * 60 * 60 * 1000; // 30 days, matches MVCP M.10's session TTL
const adminSessions = new Map(); // token -> expiresAt

function parseCookies(req) {
  const header = req.headers.cookie || "";
  const cookies = {};
  for (const pair of header.split(";")) {
    const idx = pair.indexOf("=");
    if (idx === -1) continue;
    cookies[pair.slice(0, idx).trim()] = decodeURIComponent(pair.slice(idx + 1).trim());
  }
  return cookies;
}

// T30: two accepted paths, either is enough — the ADMIN_PASSWORD cookie
// (T6, unchanged) stays as a fallback channel so nobody's locked out of the
// backend before any users.role='admin' account has been created by hand;
// requireUserSession + role='admin' (below, hoisted — same module scope) is
// the real per-admin identity path, MVCP M.10's stated rule for
// /api/admin/*. Calls requireUserSession before it's declared further down
// this file — fine, `function` declarations are fully hoisted.
function isAdminAuthed(req) {
  const token = parseCookies(req)[ADMIN_SESSION_COOKIE];
  if (token) {
    const expiresAt = adminSessions.get(token);
    if (expiresAt && expiresAt >= Date.now()) return true;
    adminSessions.delete(token);
  }
  const user = requireUserSession(req);
  return !!(user && user.role === "admin");
}

// Who to attribute an admin action to (T30's "credit_ledger 里能查到是哪个
//管理员做的") — null when the request came in over the legacy shared
// ADMIN_PASSWORD channel, which has no per-admin identity to attribute to.
function adminActorUserId(req) {
  const user = requireUserSession(req);
  return user && user.role === "admin" ? user.id : null;
}

// User account login (dev-plan-3.md T19; dressup-dance-room-mvcp.md
// M.1/M.10) — a separate cookie/session table from admin_session above, on
// purpose: this is for viewers, not the single shared admin credential, and
// the two must never be confused for one another.
const USER_SESSION_COOKIE = "user_session";
const USER_SESSION_TTL_MS = 30 * 24 * 60 * 60 * 1000; // 30 days, MVCP M.10
const EMAIL_VERIFY_TTL_MS = 24 * 60 * 60 * 1000; // 24 hours, MVCP M.10

// T20: no email-delivery vendor has been picked yet (dev-plan-3.md §1's
// open question — SMTP vs. an HTTP-API provider like Resend/SendGrid).
// This is the one seam a real integration plugs into later; nothing else
// needs to change. For now it logs, and outside production also returns
// the link directly so registering can be tested end to end without a
// real inbox.
function sendVerificationEmail(email, token) {
  const verifyUrl = `/api/auth/verify?token=${token}`;
  console.log(`[email_verify] would send to ${email}: ${verifyUrl}`);
  return verifyUrl;
}

// T25: no vision-model vendor has been picked yet (dev-plan-4.md §1.2 item
// 2 — needed because mode 2's uploader has no admin around to hand-write
// garments.appearanceDescriptor the way admin_seed garments do). Same seam
// pattern as sendVerificationEmail above: today it's a fixed placeholder,
// swapping in a real vendor later is a one-function change, callers (T27)
// don't need to know the difference.
const VISION_API_KEY = process.env.VISION_API_KEY || "";
async function describeGarmentImage(absImagePath) {
  if (!VISION_API_KEY) return "用户上传的服装";
  throw new Error("vision vendor not implemented — set VISION_API_KEY only once a provider is wired up");
}

// T35 (dev-plan-5.md): same seam as describeGarmentImage above, for mode
// 3's uploaded face photos — appearanceDescriptor has no admin to
// hand-write it either, same underlying gap. Shares VISION_API_KEY (one
// vendor question, not two) since both are "describe an uploaded photo"
// calls to whatever vision model eventually gets picked.
async function describeCharacterImage(absImagePath) {
  if (!VISION_API_KEY) return "用户上传的人物形象";
  throw new Error("vision vendor not implemented — set VISION_API_KEY only once a provider is wired up");
}

// T26: same seam pattern, for image-content moderation (dev-plan-4.md §1.2
// item 1 — the requirements doc names a vendor as "TBD" and never actually
// lists it as its own task, so this is that gap filled in). Every call logs
// to moderation_log (M.9) regardless of which branch runs, so the audit
// trail exists before a real vendor does. `assetId` is the caller's own
// stable id for the upload (T27 passes the just-saved file's relPath, since
// at moderation time there's no garments.id yet — moderation runs before
// the garment record is created, per dev-plan-4.md T27's ordering).
const MODERATION_API_KEY = process.env.MODERATION_API_KEY || "";
async function moderateGarmentImage(absImagePath, assetId) {
  let verdict, reason;
  if (!MODERATION_API_KEY) {
    // No vendor configured: default-permissive placeholder pass (T2's
    // upload endpoint already enforces the real trust-boundary checks —
    // file type by magic bytes, 8MB cap, EXIF-stripped re-encode — this is
    // only the *content* check, which nothing here can actually perform
    // without a vendor).
    verdict = "auto_pass";
    reason = null;
  } else {
    throw new Error("moderation vendor not implemented — set MODERATION_API_KEY only once a provider is wired up");
  }
  moderationLog.create({ assetType: "garment_upload", assetId, verdict, reason, reviewedBy: "system" });
  return { approved: verdict === "auto_pass", verdict, reason };
}

// T32 (dev-plan-5.md): same seam pattern as T26 above, but for mode 3's
// uploaded face photos against a "sensitive figure" blacklist (需求文档 5
// 节 — e.g. filtering politically sensitive likenesses), not general image
// content. No vendor has been picked (needs research, dev-plan-5.md §1.2
// item 1). Default policy when unconfigured is default-permissive
// (auto_pass) — deliberately confirmed with the user rather than assumed,
// since the risk profile here (a real uploaded face, potentially a
// sensitive public figure) is not the same as T26's garment photos, where
// a wrong default-pass is low-stakes. Do not silently change this default
// without asking again.
const FACE_BLACKLIST_API_KEY = process.env.FACE_BLACKLIST_API_KEY || "";
async function moderateFaceBlacklist(absImagePath, assetId) {
  let verdict, reason;
  if (!FACE_BLACKLIST_API_KEY) {
    verdict = "auto_pass";
    reason = null;
  } else {
    throw new Error("face-blacklist vendor not implemented — set FACE_BLACKLIST_API_KEY only once a provider is wired up");
  }
  moderationLog.create({ assetType: "character_upload", assetId, verdict, reason, reviewedBy: "system" });
  return { approved: verdict === "auto_pass", verdict, reason };
}

// T21: mirrors live.html/dance.html's own setCookie() exactly (path=/,
// samesite=lax, no httponly, max-age in seconds, 365-day TTL) — these are
// the same viewer_uid/viewer_nickname cookies those pages already read
// with plain client-side JS, not a new cookie scheme.
function viewerIdentityCookie(name, value) {
  return `${name}=${encodeURIComponent(value)}; Max-Age=${365 * 86400}; Path=/; SameSite=Lax`;
}

function hashPassword(password) {
  const salt = crypto.randomBytes(16).toString("hex");
  const hash = crypto.scryptSync(password, salt, 64).toString("hex");
  return `${salt}:${hash}`;
}

function verifyPassword(password, stored) {
  const [salt, hash] = (stored || "").split(":");
  if (!salt || !hash) return false;
  const candidate = crypto.scryptSync(password, salt, 64);
  const expected = Buffer.from(hash, "hex");
  // scryptSync's output length is fixed by the third argument above, so
  // both buffers are always the same length — timingSafeEqual would throw
  // otherwise, but that can't happen here.
  return crypto.timingSafeEqual(candidate, expected);
}

// Returns the logged-in user (plain object, MVCP M.1 shape) or null. Free
// endpoints (/api/dance/*) don't call this at all — only routes that
// actually need an account (T20's email verify, T21's identity binding,
// anything paid in period 4) do.
function requireUserSession(req) {
  const token = parseCookies(req)[USER_SESSION_COOKIE];
  if (!token) return null;
  const session = userSessions.findByToken(token);
  if (!session || session.kind !== "session") return null;
  return userStore.get(session.userId);
}

// Generic CRUD router for the three cold-start asset libraries (T3-T5) —
// GET list / POST create / PATCH update / DELETE, backed by store.js. The
// three entities' shapes differ (see MVCP M.3/M.4/M.5) but the routing and
// validation boilerplate is identical, so this is mounted three times below
// instead of copy-pasted.
function mountCrud(prefix, store, opts = {}) {
  const { requiredFields = [], sanitize = (b) => b, onCreate, onUpdate, onDelete } = opts;

  function missingField(body) {
    return requiredFields.find((f) => {
      const v = body[f];
      return v === undefined || v === null || (typeof v === "string" && !v.trim());
    });
  }

  return function handle(pathname, req, res) {
    if (pathname === prefix && req.method === "GET") {
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(JSON.stringify(store.list()));
      return true;
    }

    if (pathname === prefix && req.method === "POST") {
      readJsonBody(req)
        .then((body) => {
          const missing = missingField(body);
          if (missing) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: `${missing} required` }));
            return;
          }
          const item = store.create(sanitize(body));
          if (onCreate) onCreate(item, store);
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify(item));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return true;
    }

    if (pathname.startsWith(`${prefix}/`) && req.method === "PATCH") {
      const id = pathname.slice(prefix.length + 1);
      readJsonBody(req)
        .then((body) => {
          // Partial update: only reject an explicit blank-out of a required
          // field, not the field's mere absence from this patch.
          const missing = requiredFields.find((f) => f in body && missingField({ [f]: body[f] }) === f);
          if (missing) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: `${missing} required` }));
            return;
          }
          const updated = store.update(id, sanitize(body, true));
          if (!updated) {
            res.writeHead(404, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "not found" }));
            return;
          }
          if (onUpdate) onUpdate(updated, store);
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify(updated));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return true;
    }

    if (pathname.startsWith(`${prefix}/`) && req.method === "DELETE") {
      const id = pathname.slice(prefix.length + 1);
      const existing = store.get(id);
      const removed = store.remove(id);
      if (removed && onDelete) onDelete(existing, store);
      res.writeHead(removed ? 200 : 404, { "Content-Type": "application/json" });
      res.end(JSON.stringify({ deleted: removed }));
      return true;
    }

    return false;
  };
}

// isDefault is a singleton across the whole characters library (2 节:
// "第一期只允许同时有一个人物被设为默认") — enforced here rather than in
// store.js, which stays schema-agnostic.
function unsetOtherDefaultCharacters(item, store) {
  if (!item.isDefault) return;
  for (const c of store.list()) {
    if (c.id !== item.id && c.isDefault) store.update(c.id, { isDefault: false });
  }
}

const charactersCrud = mountCrud("/api/admin/characters", characters, {
  requiredFields: ["name", "imageUrl", "appearanceDescriptor"],
  sanitize: (body, isPatch) =>
    isPatch
      ? body
      : {
          name: body.name,
          imageUrl: body.imageUrl,
          tags: Array.isArray(body.tags) ? body.tags : [],
          source: "admin_seed",
          ownerUserId: null,
          appearanceDescriptor: body.appearanceDescriptor,
          isDefault: Boolean(body.isDefault),
          moderationStatus: "auto_passed",
          totalSegments: null,
          remainingSegments: null,
          status: "active",
        },
  onCreate: (item, store) => {
    unsetOtherDefaultCharacters(item, store);
    // Mirrors the single image the add-character form just uploaded into
    // the gallery as its first/cover row, so admin_seed characters created
    // the old one-image way still show up correctly in the image manager.
    if (item.imageUrl) characterImages.create({ characterId: item.id, imageUrl: item.imageUrl, angleLabel: "主图", isCover: true });
  },
  onUpdate: unsetOtherDefaultCharacters,
  // character-images has no FK constraint of its own (store.js is
  // schema-agnostic) — deleting a character would otherwise leave its
  // gallery rows orphaned forever.
  onDelete: (character) => {
    if (!character) return;
    for (const img of characterImages.list().filter((i) => i.characterId === character.id)) characterImages.remove(img.id);
  },
});

const garmentsCrud = mountCrud("/api/admin/garments", garments, {
  requiredFields: ["name", "imageUrl", "appearanceDescriptor"],
  sanitize: (body, isPatch) =>
    isPatch
      ? body
      : {
          name: body.name,
          category: body.category || "",
          thumbnailUrl: body.thumbnailUrl || body.imageUrl,
          imageUrl: body.imageUrl,
          appearanceDescriptor: body.appearanceDescriptor,
          source: "admin_seed",
          ownerUserId: null,
          moderationStatus: "approved",
          isActive: body.isActive === undefined ? true : Boolean(body.isActive),
        },
});

const danceRefsCrud = mountCrud("/api/admin/dance-refs", danceRefs, {
  requiredFields: ["name", "videoUrl", "motionDescriptor"],
  sanitize: (body, isPatch) =>
    isPatch
      ? body
      : {
          name: body.name,
          videoUrl: body.videoUrl,
          styleTags: Array.isArray(body.styleTags) ? body.styleTags : [],
          durationSec: body.durationSec || null,
          motionDescriptor: body.motionDescriptor,
          copyrightSource: "test_placeholder",
          isActive: body.isActive === undefined ? true : Boolean(body.isActive),
        },
});

// Setting isCover on one image unsets it on the character's other images
// (singleton-per-characterId, same idea as unsetOtherDefaultCharacters) and
// mirrors the url onto characters.imageUrl. h3AssetUrl/falAssetUrl are
// forward-once caches keyed off the OLD imageUrl (ensureH3AssetUrl/
// ensureFalAssetUrl below) — a cover swap must clear them or generation
// keeps sending the previous photo.
function syncCoverToCharacter(image, store) {
  if (!image.isCover) return;
  for (const img of store.list()) {
    if (img.id !== image.id && img.characterId === image.characterId && img.isCover) store.update(img.id, { isCover: false });
  }
  characters.update(image.characterId, { imageUrl: image.imageUrl, h3AssetUrl: null, falAssetUrl: null });
}

// Deleting the cover image must not leave characters.imageUrl pointing at a
// gallery row that no longer exists — promote whatever's left, if anything.
function promoteNewCoverOnDelete(deletedImage, store) {
  if (!deletedImage || !deletedImage.isCover) return;
  const remaining = store.list().filter((img) => img.characterId === deletedImage.characterId);
  if (remaining.length === 0) return;
  store.update(remaining[0].id, { isCover: true });
  characters.update(deletedImage.characterId, { imageUrl: remaining[0].imageUrl, h3AssetUrl: null, falAssetUrl: null });
}

const characterImagesCrud = mountCrud("/api/admin/character-images", characterImages, {
  requiredFields: ["characterId", "imageUrl"],
  sanitize: (body, isPatch) =>
    isPatch
      ? body
      : { characterId: body.characterId, imageUrl: body.imageUrl, angleLabel: body.angleLabel || "", isCover: Boolean(body.isCover) },
  onCreate: (item, store) => {
    // A character's first image has nothing to be "cover" relative to —
    // make it the cover automatically instead of leaving the gallery
    // coverless until the admin remembers to flip a checkbox.
    const siblingCount = store.list().filter((img) => img.characterId === item.characterId).length;
    if (siblingCount === 1 && !item.isCover) {
      store.update(item.id, { isCover: true });
      item.isCover = true;
    }
    syncCoverToCharacter(item, store);
  },
  onUpdate: syncCoverToCharacter,
  onDelete: promoteNewCoverOnDelete,
});

function h3ConsoleFetch(pathAndQuery, options) {
  return new Promise((resolve, reject) => {
    const proxyReq = http.request(
      {
        hostname: H3_CONSOLE_URL.hostname,
        port: H3_CONSOLE_URL.port || 80,
        path: `${H3_CONSOLE_URL.pathname}${pathAndQuery}`,
        method: (options && options.method) || "GET",
        headers: { Authorization: `Bearer ${H3_CONSOLE_TOKEN}`, "Content-Type": "application/json" },
      },
      (proxyRes) => {
        let data = "";
        proxyRes.on("data", (c) => (data += c));
        proxyRes.on("end", () => {
          try {
            resolve(JSON.parse(data));
          } catch (err) {
            reject(err);
          }
        });
      }
    );
    proxyReq.on("error", reject);
    if (options && options.body) proxyReq.write(JSON.stringify(options.body));
    proxyReq.end();
  });
}

// timeoutMs default matches the original text-only prompt-optimize use —
// the QC caller (multi-image, much bigger payload) passes a longer one.
function glmChat(messages, timeoutMs = 15000) {
  return new Promise((resolve, reject) => {
    const body = JSON.stringify({ model: GLM_MODEL, messages, temperature: 0.7 });
    const req = https.request(
      {
        hostname: GLM_HOST,
        path: GLM_PATH,
        method: "POST",
        headers: { Authorization: `Bearer ${GLM_API_KEY}`, "Content-Type": "application/json", "Content-Length": Buffer.byteLength(body) },
      },
      (res) => {
        let data = "";
        res.on("data", (c) => (data += c));
        res.on("end", () => {
          try {
            resolve(JSON.parse(data));
          } catch (err) {
            reject(err);
          }
        });
      }
    );
    req.on("error", reject);
    req.setTimeout(timeoutMs, () => req.destroy(new Error("GLM request timed out")));
    req.write(body);
    req.end();
  });
}

// ---- T24: Stripe topup, with a mock fallback until a real test-mode key
// exists (2026-09-03: user said "先做一个 mock，我明天再给你真实测试的
// key") — createCheckoutSession() is the single seam both paths sit
// behind, matching T20/T25/T26's "one pluggable function" precedent. ----
const pendingMockCheckouts = new Map(); // token -> {userId, tierKey, expiresAt}
const MOCK_CHECKOUT_TTL_MS = 30 * 60 * 1000;

// Both the mock path (GET /api/credits/mock-checkout) and the real path
// (POST /api/credits/webhook) end up here — one place that actually moves
// money, so there's exactly one code path responsible for the
// ledger/idempotency bookkeeping (topup()'s paymentRef dedup, db.js).
function completeTopup({ userId, tierKey, paymentRef }) {
  const tier = pricing.get(tierKey);
  if (!tier || tier.kind !== "topup_tier" || !tier.isActive) {
    throw new Error(`unknown or inactive topup tier: ${tierKey}`);
  }
  return creditLedger.topup({ userId, amount: tier.credits, reason: "topup", paymentRef });
}

// Real Stripe path: plain REST via global fetch, no stripe npm SDK — this
// project has no package.json/dependencies, and Stripe's Checkout Sessions
// API is documented as plain form-encoded REST (same "use fetch, not a new
// dependency" call as forwardToH3Assets in uploads.js). Untested against a
// real Stripe account as of this commit — no test-mode key exists yet, see
// dev-plan-4.md §1.2 item 4.
async function createRealStripeCheckoutSession({ userId, tierKey, tier }) {
  const params = new URLSearchParams({
    mode: "payment",
    "line_items[0][quantity]": "1",
    "line_items[0][price_data][currency]": "usd",
    "line_items[0][price_data][unit_amount]": String(tier.priceCents),
    "line_items[0][price_data][product_data][name]": `${tier.credits} credits`,
    success_url: `${APP_BASE_URL}/dance.html?topup=success`,
    cancel_url: `${APP_BASE_URL}/dance.html?topup=cancelled`,
    "metadata[userId]": userId,
    "metadata[tierKey]": tierKey,
  });
  const res = await fetch("https://api.stripe.com/v1/checkout/sessions", {
    method: "POST",
    headers: { Authorization: `Bearer ${STRIPE_SECRET_KEY}`, "Content-Type": "application/x-www-form-urlencoded" },
    body: params,
  });
  const session = await res.json();
  if (!res.ok) throw new Error(session.error?.message || "Stripe checkout session creation failed");
  return session.url;
}

// Mock path: no real payment happens, but the whole checkout -> redirect ->
// credited loop is real and testable today — T29's UI and topup()'s own
// dedup logic don't need to wait on a real Stripe key to be built and
// exercised end to end.
function createMockCheckoutUrl({ userId, tierKey }) {
  const token = crypto.randomUUID();
  pendingMockCheckouts.set(token, { userId, tierKey, expiresAt: Date.now() + MOCK_CHECKOUT_TTL_MS });
  return `/api/credits/mock-checkout?token=${token}`;
}

async function createCheckoutSession({ userId, tierKey }) {
  const tier = pricing.get(tierKey);
  if (!tier || tier.kind !== "topup_tier" || !tier.isActive) {
    throw new Error(`unknown or inactive topup tier: ${tierKey}`);
  }
  if (!STRIPE_SECRET_KEY) return { url: createMockCheckoutUrl({ userId, tierKey }) };
  return { url: await createRealStripeCheckoutSession({ userId, tierKey, tier }) };
}

// Stripe's documented signature scheme (Stripe-Signature header:
// "t=<timestamp>,v1=<hex hmac>"): HMAC-SHA256 over "<timestamp>.<raw body>"
// with the webhook signing secret, compared in constant time. Hand-rolled
// rather than the stripe SDK for the same "no new dependency" reason as
// the rest of this integration.
function verifyStripeWebhookSignature(rawBody, signatureHeader, secret) {
  if (!signatureHeader) return false;
  const parts = Object.fromEntries(
    signatureHeader
      .split(",")
      .map((kv) => kv.split("="))
      .filter((kv) => kv.length === 2)
  );
  if (!parts.t || !parts.v1) return false;
  const expected = crypto.createHmac("sha256", secret).update(`${parts.t}.${rawBody}`).digest("hex");
  let expectedBuf, actualBuf;
  try {
    expectedBuf = Buffer.from(expected, "hex");
    actualBuf = Buffer.from(parts.v1, "hex");
  } catch {
    return false;
  }
  return expectedBuf.length === actualBuf.length && crypto.timingSafeEqual(expectedBuf, actualBuf);
}

// Distilled from docs/h3skill.md (MiniMax's own H3 prompt-writing methodology) down to the one
// path that applies here: T2VA (no reference images — every chat prompt is plain text) on a clip
// fixed at ~10s (H3_GEN_PARAMS.frames / FPS). At that length it's one continuous shot, never a
// multi-cut montage — an earlier version asked for "shot-by-shot" and reliably got 4-5 fake cuts
// with timestamps running past the clip's own length, which the model can't actually deliver.
const PROMPT_OPTIMIZE_SYSTEM = `You are writing H3 text-to-video generation prompts (T2VA mode — no
reference images, pure text-to-video). Expand the user's short request (may be in Chinese or English)
into the official H3 three-field format, in this exact order, using these exact field labels:

integrated_multimodal_description: [Shot 1] one short style statement, e.g. "Live-action, cinematic."
Then describe, in one continuous unbroken shot (the clip is only about 10 seconds long — never split
into multiple shots or write more than [Shot 1]): the setting, the subject's specific action, and ONE
dominant camera movement using this vocabulary — Zoom In/Out, Push In/Pull Out, Pan Left/Right, Truck
Left/Right, Tilt Up/Down, Pedestal Up/Down, Arc Shot, Tracking Shot, Static Shot, Shake Slightly/
Strongly, POV, Roll Clockwise/Counterclockwise — stated as type + amplitude (small/large) + speed
(slow/fast). Describe light concretely: where it comes from, what it hits, what effect it creates.
Never use hollow quality words alone (8K, HD, masterpiece, stunning, cinematic used alone, beautiful,
high quality) — replace them with what is actually visible. 60-100 English words.

overall_soundscape: 1-4 English sentences describing the ambient environmental sound the scene would
naturally have.

non_diegetic_music: 1-3 English sentences describing the score the audience (not the characters) hears,
or exactly "N/A" if none fits.

Output only these three labeled fields in this exact order and exact labels, nothing else — no
preamble, no extra commentary, no markdown formatting.`;

// Best-effort — a viewer's short chat line ("一只猫跳舞") makes for a weak
// H3 prompt on its own. Never let a GLM outage or slow response block
// generation: on any failure this just falls back to the original text.
async function optimizePrompt(userPrompt) {
  if (!GLM_API_KEY) return userPrompt;
  try {
    const res = await glmChat([
      { role: "system", content: PROMPT_OPTIMIZE_SYSTEM },
      { role: "user", content: userPrompt },
    ]);
    const text = res.choices && res.choices[0] && res.choices[0].message && res.choices[0].message.content;
    return text ? text.trim() : userPrompt;
  } catch {
    return userPrompt;
  }
}

// ---- Dance video QC (2026-09): AI-assisted check that a generated dance
// clip actually shows the right garment on a consistent character from
// first frame to last. Reuses glmChat() — confirmed live (2026-09-07) that
// the coding-plan endpoint/glm-5.3-flash model accepts multiple image_url
// content parts and correctly distinguishes them, so no new vision vendor
// is needed. ffmpeg extracts frames locally, same "shell out to a system
// media tool" pattern uploads.js already uses for sips.
function imageDataUrl(absPath) {
  const ext = path.extname(absPath).slice(1).toLowerCase();
  const mime = ext === "jpg" ? "jpeg" : ext;
  return `data:image/${mime};base64,${fs.readFileSync(absPath).toString("base64")}`;
}

// Reference photos (character/garment uploads) can be several MB at full
// resolution — 5 of those in one GLM request is what pushed the very first
// QC call past a 15s timeout. Downscales via `sips` (same tool
// stripMetadataAndSave already shells out to) before encoding; falls back
// to the original file if sips fails for any reason rather than blocking
// the whole check on a resize hiccup.
function resizedImageDataUrl(absPath, maxDim) {
  const tmpPath = path.join(os.tmpdir(), `qc-resize-${crypto.randomUUID()}${path.extname(absPath) || ".jpg"}`);
  try {
    execFileSync("sips", ["-Z", String(maxDim), absPath, "--out", tmpPath], { stdio: "pipe" });
    return imageDataUrl(tmpPath);
  } catch {
    return imageDataUrl(absPath);
  } finally {
    fs.rm(tmpPath, { force: true }, () => {});
  }
}

// Goes through this clip's own /lib/video/:id route rather than duplicating
// its source dispatch (manual/fal videoUrl redirect vs H3 Console proxy) —
// whatever a viewer's <video> tag would actually receive is what gets QC'd.
async function downloadClipVideo(clipId) {
  const res = await fetch(`http://localhost:${PORT}/lib/video/${clipId}`);
  if (!res.ok) throw new Error(`failed to fetch clip video: HTTP ${res.status}`);
  const buf = Buffer.from(await res.arrayBuffer());
  const tmpPath = path.join(os.tmpdir(), `qc-${clipId}-${crypto.randomUUID()}.mp4`);
  fs.writeFileSync(tmpPath, buf);
  return tmpPath;
}

// Start / middle / near-end — enough to catch a garment swap or identity
// drift partway through without paying to sample every frame.
function extractQcFrames(videoAbsPath, durationSec) {
  const dur = durationSec && durationSec > 1 ? durationSec : 10;
  const timestamps = [0.5, Math.max(0.5, dur / 2), Math.max(0.5, dur - 0.5)];
  const tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), "qc-frames-"));
  try {
    return timestamps.map((t, i) => {
      const outPath = path.join(tmpDir, `frame${i}.jpg`);
      // scale=480:-2 caps width at the clip's own native width (DANCE_GEN_PARAMS
      // is 480x832) — no upscaling, just keeps a wider source from ballooning
      // the request; -2 keeps height even (required by some encoders/filters).
      execFileSync("ffmpeg", ["-y", "-ss", String(t), "-i", videoAbsPath, "-frames:v", "1", "-vf", "scale='min(480,iw)':-2", "-q:v", "3", outPath], { stdio: "pipe" });
      return imageDataUrl(outPath);
    });
  } finally {
    fs.rmSync(tmpDir, { recursive: true, force: true });
  }
}

const QC_PROMPT = `你是短视频质检员。你会收到 5 张图片，按顺序是：
1. 人物参考照（这个角色应有的脸型、发型、体态）
2. 衣服参考照（视频里应该穿着的服装）
3-5. 同一条跳舞视频的开头、中间、结尾三帧截图

请检查两件事：
1. 视频里穿的衣服，颜色/款式/剪裁是否与第 2 张衣服参考照一致
2. 从开头到结尾，人物的脸型、发型、体态是否与第 1 张人物参考照保持一致，且开头/中间/结尾三帧之间人物本身是否连贯、没有跑偏或变成另一个人

只输出一个 JSON 对象，不要输出其他任何文字或 markdown 代码块标记，格式严格为：
{"verdict":"correct"} 或 {"verdict":"incorrect","note":"一两句话说明具体是衣服问题还是人物问题，哪里不对"}`;

function parseQcVerdict(text) {
  const match = text.match(/\{[\s\S]*\}/);
  if (!match) throw new Error("GLM response contained no JSON object");
  const parsed = JSON.parse(match[0]);
  if (parsed.verdict !== "correct" && parsed.verdict !== "incorrect") throw new Error(`unexpected verdict: ${parsed.verdict}`);
  return { verdict: parsed.verdict, note: parsed.verdict === "incorrect" ? String(parsed.note || "").trim() || "AI 未说明具体原因" : "" };
}

// Runs the AI check for one dance clip. Callers write the result onto the
// library record themselves — this only returns it.
async function runDanceClipQc(clip) {
  if (!GLM_API_KEY) throw new Error("GLM_API_KEY not configured");
  const character = characters.get(clip.characterId);
  const garment = garments.get(clip.garmentId);
  if (!character || !garment) throw new Error("clip is missing its character/garment reference");

  const videoPath = await downloadClipVideo(clip.id);
  let frames;
  try {
    frames = extractQcFrames(videoPath, clip.duration);
  } finally {
    fs.unlinkSync(videoPath);
  }

  const refImages = [character.imageUrl, garment.imageUrl].map((relPath) => resizedImageDataUrl(path.join(__dirname, relPath), 480));
  const res = await glmChat(
    [
      {
        role: "user",
        content: [{ type: "text", text: QC_PROMPT }, ...[...refImages, ...frames].map((url) => ({ type: "image_url", image_url: { url } }))],
      },
    ],
    60000 // 5 images is a much bigger payload than optimizePrompt's text-only default use
  );
  const text = res.choices && res.choices[0] && res.choices[0].message && res.choices[0].message.content;
  if (!text) throw new Error(`GLM returned no content: ${JSON.stringify(res).slice(0, 300)}`);
  const { verdict, note } = parseQcVerdict(text);
  return { qcStatus: verdict, qcNote: note ? `[AI] ${note}` : "" };
}

// In-memory only (not persisted) — a batch is cheap enough to just re-run
// if the server restarts mid-way, unlike generationJobs' real H3 spend.
const qcBatchJobs = new Map(); // batchId -> {total, checked, results:[{clipId,qcStatus,qcNote,error?}], status:"running"|"done", cancelled}

async function runQcBatch(batchId, clipIds) {
  const job = qcBatchJobs.get(batchId);
  for (const clipId of clipIds) {
    if (job.cancelled) break;
    const lib = getLibrary();
    const clip = lib.find((c) => c.id === clipId);
    if (!clip) {
      job.results.push({ clipId, error: "clip no longer exists" });
      job.checked++;
      continue;
    }
    try {
      const { qcStatus, qcNote } = await runDanceClipQc(clip);
      clip.qcStatus = qcStatus;
      clip.qcNote = qcNote;
      clip.published = qcStatus === "correct"; // 通过验证的自动上架
      saveLibrary(lib);
      job.results.push({ clipId, qcStatus, qcNote });
    } catch (err) {
      job.results.push({ clipId, error: err.message });
    }
    job.checked++;
    // Sequential, not concurrent, with a small gap — GLM is far more
    // resilient than H3 Console, but a burst of ffmpeg child processes
    // plus large-image requests firing all at once is still worth avoiding.
    await new Promise((r) => setTimeout(r, 800));
  }
  job.status = "done";
}

// ---- Live channel: shared virtual playhead + prompt queue ----
// Persisted to live-state.json (see saveLiveState/loadLiveState) so a
// restart resumes the schedule instead of starting cold; ensureSchedule's
// own past-entry trimming naturally handles a state file that's gone stale
// (server was down long enough that every persisted entry is in the past).
const FILLER_DURATION_MS = 30000; // keep the schedule filled at least this far ahead
const H3_GEN_PARAMS = { width: 480, height: 832, frames: 240, steps: 20, turbo: false, seed: 0 };
const FPS = 24;

// dance.html's own generation params (architecture.md 2.4: each channel
// keeps an independent H3_GEN_PARAMS even though the values happen to
// match live.html's today — don't merge the two constants).
const DANCE_GEN_PARAMS = { width: 480, height: 832, frames: 240, steps: 20, turbo: false, seed: 0 };

const initialLiveState = loadLiveState();
let schedule = initialLiveState.schedule; // [{clip, startAt, endAt, requestedBy?}]
let promptQueue = initialLiveState.promptQueue; // [{id, prompt, nickname?, status, clip?, error?, submittedAt, h3JobId?}]
let chatMessages = initialLiveState.chatMessages; // [{id, uid, nickname, text, createdAt, status}]

const initialDanceState = loadDanceState();
// { [characterId]: { schedule: [{videoId, startAt, endAt, requestedBy?}],
//                     queue: [{id, garmentId, characterId, nickname?, status, jobId?, videoId?, error?, submittedAt, votes}],
//                     priorityInbox: [{videoId, requestedBy}] } } — one room
// per character (see getDanceRoom above). priorityInbox: T34 (dev-plan-5.md;
// schema M.8) paid_boost (mode 3) clips land here once ready, never in a
// room's vote-ranked queue — that room's pickNextDanceClip drains this
// first, unconditionally, every tick.
let danceRooms = initialDanceState.danceRooms;

// How often ensureSchedule/ensureDanceSchedule tick — configurable so tests
// don't have to wait out a real 2s to see a schedule fill.
const SCHEDULE_TICK_MS = Number(process.env.SCHEDULE_TICK_MS) || 2000;

// ---- chat + moderation ----
// ponytail: a starter blocklist, not a real content-policy list — swap in
// whatever the actual moderation requirements are. Substring match on the
// lowercased text; cheap and deterministic. Anything this doesn't catch
// (content that's fine as *text* but unsafe to *generate*) falls through to
// the H3 console's own generation-time safety checker — a rejected/failed
// job there just surfaces as a normal "failed" queue entry.
const BANNED_WORDS = ["色情", "porn", "自杀", "血腥暴力", "毒品"];
function moderateText(text) {
  const lower = text.toLowerCase();
  const hit = BANNED_WORDS.find((w) => lower.includes(w));
  if (hit) return { ok: false, reason: `包含违禁词` };
  return { ok: true };
}

const CHAT_HISTORY_LIMIT = 300;
function pushChatMessage(msg) {
  chatMessages.push(msg);
  if (chatMessages.length > CHAT_HISTORY_LIMIT) chatMessages = chatMessages.slice(-CHAT_HISTORY_LIMIT);
}
function updateChatStatus(id, status) {
  const msg = chatMessages.find((m) => m.id === id);
  if (msg) msg.status = status;
}

// Shared by /api/chat (after moderation) and /api/prompt (direct API use,
// e.g. testing) — looks up a library match or kicks off generation, exactly
// like before chat existed. `nickname` is optional (empty for /api/prompt).
function submitPromptToQueue(id, prompt, nickname) {
  const entry = { id, prompt, nickname: nickname || null, submittedAt: Date.now(), votes: [] };
  const match = findLibraryMatch(normalizePrompt(prompt));
  if (match) {
    entry.status = "matched";
    entry.clip = match;
    promptQueue.push(entry);
    return { status: "matched", clip: match };
  }
  entry.status = "generating";
  promptQueue.push(entry);
  generateForPrompt(entry); // fire and forget — polled via /api/live/state
  return { status: "generating", id: entry.id };
}

function normalizePrompt(s) {
  return s.trim().toLowerCase().replace(/\s+/g, " ");
}
function findLibraryMatch(promptNorm) {
  return getLibrary().find((c) => {
    const zh = normalizePrompt(c.prompt);
    const en = c.promptEn ? normalizePrompt(c.promptEn) : null;
    return (
      zh === promptNorm ||
      zh.includes(promptNorm) ||
      promptNorm.includes(zh) ||
      (en && (en === promptNorm || en.includes(promptNorm) || promptNorm.includes(en)))
    );
  });
}

// Idle fallback pick avoids anything played within this window, so a clip
// that just aired doesn't come back around too soon. Falls back to ignoring
// the cooldown (keeping only the immediate-repeat guard) if literally
// everything is on cooldown, rather than ever stalling the schedule.
const REPEAT_COOLDOWN_MS = 20 * 60 * 1000;

function markPlayed(id) {
  const lib = getLibrary();
  const clip = lib.find((c) => c.id === id);
  if (!clip) return;
  clip.lastPlayedAt = Date.now();
  clip.playCount = (clip.playCount || 0) + 1;
  saveLibrary(lib);
}

// T36 (dev-plan-5.md): dance.html-only, deliberately not folded into the
// shared markPlayed() above — live.html's text-channel clips never have a
// user_paid character behind them, and keeping this explicit (called only
// from the two dance-specific scheduling call sites) matches
// architecture.md 2.1's "two independent product lines" rather than
// silently special-casing the shared helper. A clip's first play already
// happened via T34's priorityInbox insert ("确定性上镜"); every play after
// that — including this same clip recurring through the normal random-fill
// pool — keeps consuming the same purchased quota until it runs out.
function consumeCharacterSegment(clip) {
  if (!clip.characterId) return;
  const character = characters.get(clip.characterId);
  if (!character || character.source !== "user_paid" || character.status !== "active" || character.remainingSegments == null) return;
  const remainingSegments = Math.max(0, character.remainingSegments - 1);
  characters.update(character.id, { remainingSegments, status: remainingSegments === 0 ? "expired" : "active" });
}

// Consumed entries are spliced out immediately rather than left as
// status:"scheduled" — once a clip is in `schedule` it shows up via
// current/upNext, so keeping a second, never-cleared copy in promptQueue
// just grows forever and duplicates the same info.
// Returns {clip, requestedBy, chatId} — chatId lets the caller flip the
// originating chat message to "scheduled" once it's actually about to air.
// Among entries of the same status, the most-upvoted prompt goes first
// (ties broken by submission order) — lets chat bump a favorite to the
// front of the line instead of strict FIFO.
function voteCount(q) {
  return (q.votes || []).length;
}
// Shared by live's promptQueue and dance's freeQueue (T11) — takes the queue
// array as a param rather than closing over a module-scope variable so both
// channels' independent queues can use it.
function pickBestIndexByStatus(queue, status) {
  let bestIdx = -1;
  for (let i = 0; i < queue.length; i++) {
    const q = queue[i];
    if (q.status !== status) continue;
    if (bestIdx === -1) {
      bestIdx = i;
      continue;
    }
    const best = queue[bestIdx];
    if (voteCount(q) > voteCount(best)) bestIdx = i;
  }
  return bestIdx;
}
// Random-fill fallback shared by live's pickNextClip and dance's
// pickNextDanceClip (T11) — least-played-first within a cooldown-filtered
// pool, so idle filler time rotates evenly instead of a few clips dominating
// by chance. `pool` is caller-filtered (live excludes dance channel clips
// and vice versa, architecture.md 2.1: independent schedules per channel).
function pickLeastPlayedClip(pool, prevId) {
  if (!pool.length) return null;
  const notPrev = pool.length > 1 ? pool.filter((c) => c.id !== prevId) : pool;
  const now = Date.now();
  // Never-played clips (no lastPlayedAt) are always eligible — genuinely
  // random among everything that isn't on cooldown, no bias toward "fresh".
  const offCooldown = notPrev.filter((c) => !c.lastPlayedAt || now - c.lastPlayedAt > REPEAT_COOLDOWN_MS);
  const candidates = offCooldown.length ? offCooldown : notPrev;
  const minPlays = Math.min(...candidates.map((c) => c.playCount || 0));
  const leastPlayed = candidates.filter((c) => (c.playCount || 0) === minPlays);
  return leastPlayed[Math.floor(Math.random() * leastPlayed.length)];
}
function pickNextClip() {
  const readyIdx = pickBestIndexByStatus(promptQueue, "ready");
  if (readyIdx !== -1) {
    const q = promptQueue.splice(readyIdx, 1)[0];
    return { clip: q.clip, requestedBy: q.nickname, chatId: q.id };
  }
  const matchedIdx = pickBestIndexByStatus(promptQueue, "matched");
  if (matchedIdx !== -1) {
    const q = promptQueue.splice(matchedIdx, 1)[0];
    return { clip: q.clip, requestedBy: q.nickname, chatId: q.id };
  }

  // dance-channel clips (T8) don't belong in live.html's random filler pool
  // — the two channels keep independent schedules (architecture.md 2.1).
  const lib = getLibrary().filter((c) => c.channel !== "dance");
  if (!lib.length) return null;
  const prev = schedule.length ? schedule[schedule.length - 1].clip.id : null;
  const clip = pickLeastPlayedClip(lib, prev);
  return clip ? { clip, requestedBy: null, chatId: null } : null;
}

const FAILED_ENTRY_TTL_MS = 20000; // how long a "generation failed" entry stays visible before cleanup

function ensureSchedule() {
  const now = Date.now();
  while (schedule.length > 1 && schedule[1].endAt <= now) schedule.shift();
  while (schedule.length === 0 || schedule[schedule.length - 1].endAt < now + FILLER_DURATION_MS) {
    const picked = pickNextClip();
    if (!picked || !picked.clip) break;
    const { clip, requestedBy, chatId } = picked;
    markPlayed(clip.id);
    if (chatId) updateChatStatus(chatId, "scheduled");
    const startAt = schedule.length ? schedule[schedule.length - 1].endAt : now;
    schedule.push({ clip, startAt, endAt: startAt + clip.duration * 1000, requestedBy });
  }
  promptQueue = promptQueue.filter((q) => q.status !== "failed" || now - q.failedAt < FAILED_ENTRY_TTL_MS);

  for (const [cid, lastSeen] of viewers) if (now - lastSeen > VIEWER_TTL_MS) viewers.delete(cid);
  saveLiveState();
}
setInterval(ensureSchedule, SCHEDULE_TICK_MS);

// ---- viewer count: anyone whose /api/live/state poll landed in the last VIEWER_TTL_MS ----
const VIEWER_TTL_MS = 12000;
const viewers = new Map(); // clientId -> lastSeenAt
// dance.html keeps its own viewer count (T17), now one per room (getRoomViewers
// above) — every room's "在线人数" is independent, none of them summed together.
const danceViewers = new Map(); // characterId -> Map<clientId, lastSeenAt>

// ---- rate limiting: cheap per-IP throttle on prompt submission ----
const RATE_LIMIT_MAX = 3;
const RATE_LIMIT_WINDOW_MS = 5 * 60 * 1000;
const rateLimitHits = new Map(); // ip -> [timestamps]
function isRateLimited(ip) {
  const now = Date.now();
  const hits = (rateLimitHits.get(ip) || []).filter((t) => now - t < RATE_LIMIT_WINDOW_MS);
  hits.push(now);
  rateLimitHits.set(ip, hits);
  return hits.length > RATE_LIMIT_MAX;
}

// Runs in the background; never blocks the live schedule or the POST /api/prompt response.
// `entry.h3JobId` set (and persisted via saveLiveState) as soon as we have it,
// so a server restart mid-generation can resume polling instead of losing
// track of the job (see resumeGenerations() at startup).
async function generateForPrompt(entry) {
  try {
    if (!entry.h3JobId) {
      if (!entry.expandedPrompt) {
        entry.expandedPrompt = await optimizePrompt(entry.prompt);
        saveLiveState();
      }
      const submitted = await h3ConsoleFetch("/v1/videos", {
        method: "POST",
        body: { prompt: entry.expandedPrompt, ...H3_GEN_PARAMS },
      });
      if (!submitted.id) throw new Error(submitted.detail || "submit failed");
      entry.h3JobId = submitted.id;
      saveLiveState();
    }

    for (let i = 0; i < 120; i++) {
      await new Promise((r) => setTimeout(r, 5000));
      const job = await h3ConsoleFetch(`/v1/videos/${entry.h3JobId}`);
      if (job.deleted_at) throw new Error("job was deleted on the H3 console before it finished");
      if (job.status === "done") {
        const clip = {
          id: job.id,
          source: "h3console",
          prompt: entry.prompt,
          fullPrompt: entry.expandedPrompt || entry.prompt,
          width: job.req.width,
          height: job.req.height,
          duration: Math.round((job.req.frames / FPS) * 10) / 10,
          partition: job.partition,
          likes: 0,
          createdAt: Date.now(),
        };
        const lib = getLibrary();
        lib.push(clip);
        saveLibrary(lib);
        entry.status = "ready";
        entry.clip = clip;
        updateChatStatus(entry.id, "ready");
        saveLiveState();
        return;
      }
      if (job.status === "error" || job.status === "failed") throw new Error(job.error || "generation failed");
    }
    throw new Error("generation timed out");
  } catch (err) {
    entry.status = "failed";
    entry.error = err.message;
    entry.failedAt = Date.now();
    updateChatStatus(entry.id, "failed");
    saveLiveState();
  }
}

// Startup recovery: resume polling any generation that was mid-flight when
// the process last exited. Anything genuinely orphaned (no h3JobId — should
// never happen given the flow above) just gets dropped as failed.
function resumeGenerations() {
  for (const entry of promptQueue) {
    if (entry.status !== "generating") continue;
    if (entry.h3JobId) generateForPrompt(entry);
    else {
      entry.status = "failed";
      entry.error = "lost track of this generation across a restart";
      entry.failedAt = Date.now();
    }
  }
}

// ---- Dressup dance room: one-step generation orchestration (T8) ----
// Mirrors generateForPrompt's shape (submit -> persist h3JobId -> poll ->
// push a library.json clip on success) but for ref2va instead of plain
// text, and persisted in generationJobs (dressup-store.js) instead of
// live-state.json's promptQueue — this is an admin/batch-driven pipeline,
// not the viewer-facing live queue, so it shouldn't share that store.

// Forwards a store record's local upload to H3 Console's /v1/assets
// (S4 spike) the first time it's needed, then caches the result on the
// record so later generations reusing the same character/garment/dance-ref
// don't re-forward the same file (MVCP M.13).
async function ensureH3AssetUrl(store, record, localUrlField) {
  if (record.h3AssetUrl) return record.h3AssetUrl;
  const absPath = path.join(__dirname, record[localUrlField]);
  const asset = await forwardToH3Assets(absPath, H3_CONSOLE_BASE, H3_CONSOLE_TOKEN);
  store.update(record.id, { h3AssetUrl: asset.url });
  return asset.url;
}

// Same caching idea as ensureH3AssetUrl, separate field (fal is a
// completely different storage service, not interchangeable with
// h3AssetUrl — M.13's note that "S4 spike only solved the H3 Console side").
async function ensureFalAssetUrl(store, record, localUrlField) {
  if (record.falAssetUrl) return record.falAssetUrl;
  const absPath = path.join(__dirname, record[localUrlField]);
  const asset = await forwardToFalAssets(absPath, FAL_API_KEY, FAL_REST_BASE);
  store.update(record.id, { falAssetUrl: asset.url });
  return asset.url;
}

// T33: submit + poll + fetch-result against fal's queue API (verified
// contract, see FAL_MODEL_ID's doc comment above and forwardToFalAssets in
// uploads.js — POST {queueHost}/{model}, poll .../requests/{id}/status,
// fetch .../requests/{id}). Kept separate from h3ConsoleFetch's shape
// (single-poll-returns-everything) since fal's status/result are two
// different endpoints, not one.
async function falSubmit(input) {
  const res = await fetch(`${FAL_QUEUE_BASE}/${FAL_MODEL_ID}`, {
    method: "POST",
    headers: { Authorization: `Key ${FAL_API_KEY}`, "Content-Type": "application/json" },
    body: JSON.stringify(input),
  });
  const body = await res.json();
  if (!res.ok || !body.request_id) throw new Error(body.detail || body.error || `fal submit failed: ${res.status}`);
  return body; // { request_id, status_url, response_url, ... }
}
async function falPollStatus(requestId) {
  const res = await fetch(`${FAL_QUEUE_BASE}/${FAL_MODEL_ID}/requests/${requestId}/status`, {
    headers: { Authorization: `Key ${FAL_API_KEY}` },
  });
  return res.json(); // { status: "IN_QUEUE"|"IN_PROGRESS"|"COMPLETED"|... }
}
async function falFetchResult(requestId) {
  const res = await fetch(`${FAL_QUEUE_BASE}/${FAL_MODEL_ID}/requests/${requestId}`, {
    headers: { Authorization: `Key ${FAL_API_KEY}` },
  });
  const body = await res.json();
  if (!res.ok || !body.video || !body.video.url) throw new Error(body.detail || body.error || "fal result missing video.url");
  return body; // { video: { url, ... }, expanded_prompt }
}

// T39 (dev-plan-5.md; schema M.11) — operator hand-curated blocklist,
// distinct from T32's automated face-blacklist model and T26's garment
// moderation (see blacklist store's own doc comment, dressup-store.js).
function isBlacklisted(targetType, targetId) {
  if (!targetId) return false;
  return blacklist.list().some((b) => b.targetType === targetType && b.targetId === targetId);
}

function pickRefDanceVideo() {
  const pool = danceRefs.list().filter((d) => d.isActive);
  if (pool.length === 0) throw new Error("no active dance-refs available");
  return pool[Math.floor(Math.random() * pool.length)];
}

// 4.6 节去重缓存：相同 (characterId, garmentId) 组合直接复用已有产物。
// qcStatus:"incorrect" 的旧片段不算数——AI 质检没过的视频保留在库里（人物/衣服溯源、
// 问题说明都还在），只是不再被当成"已经生成过"，这样纠错时重新提交就能真的再生成一条，
// 而不是又把去重缓存命中到那条坏的上面。
function findExistingGeneratedVideo(characterId, garmentId) {
  return getLibrary().find((c) => c.channel === "dance" && c.characterId === characterId && c.garmentId === garmentId && c.qcStatus !== "incorrect");
}

// Shared by the single-shot POST /api/admin/generate and the T9 batch
// endpoint: validates a (character, garment) pair, returns the cached clip
// if M.7's dedupe index already has one, otherwise queues a generationJobs
// record and fires generateDanceVideo (fire-and-forget — callers poll
// GET /api/admin/generate/:id or /api/admin/batch-gen/status for progress).
// Returns {status, body} so route handlers can just write it out.
// userId/priority (T33/T34, dev-plan-5.md): a free mode-一 pick passes
// neither (backend stays H3 Console, priority "normal"); T27 (mode 2)
// passes userId only (still "normal" — 需求文档 3 节: mode 2 stays in the
// vote-ranked queue, only mode 3 skips it); T35 (mode 3, once built) passes
// both userId and priority:"paid_boost".
function submitGeneration({ characterId, garmentId, refDanceVideoId, batchId, userId, priority }) {
  if (!characters.get(characterId) || !garments.get(garmentId)) {
    return { status: 400, body: { error: "characterId/garmentId must reference existing records" } };
  }
  const existing = findExistingGeneratedVideo(characterId, garmentId);
  if (existing) return { status: 200, body: { cached: true, clip: existing } };

  if (!refDanceVideoId) {
    try {
      refDanceVideoId = pickRefDanceVideo().id;
    } catch (err) {
      return { status: 400, body: { error: err.message } };
    }
  }
  // T33: paid requests (userId set) route to fal's real-time compute once
  // FAL_API_KEY is configured (需求文档 4.3 节双算力策略); everything else
  // — free mode-一, or a paid request before a key exists — stays on the
  // H3 Console path that's been working since T8.
  const backend = userId && FAL_API_KEY ? "fal" : "h3_console";
  const job = generationJobs.create({
    characterId,
    garmentId,
    refDanceVideoId,
    batchId: batchId || null,
    status: "queued",
    h3JobId: null,
    falRequestId: null,
    error: null,
    backend,
    userId: userId || null,
    priority: priority || "normal",
  });
  generateDanceVideo(job).catch(() => {});
  return { status: 200, body: { cached: false, jobId: job.id } };
}

// Dispatches on job.backend (T33) — H3 Console and fal.ai have genuinely
// different submit/poll/result shapes (see generateDanceVideoViaFal's doc
// comment), not just a different header, so this stays two implementations
// behind one entry point rather than one branchy function.
async function generateDanceVideo(job, opts = {}) {
  return job.backend === "fal" ? generateDanceVideoViaFal(job, opts) : generateDanceVideoViaH3(job, opts);
}

// job: a generationJobs record ({id, characterId, garmentId,
// refDanceVideoId, status, h3JobId, error, fullPrompt, backend, userId,
// priority}). Mutates it via generationJobs.update and keeps the local
// variable in sync (store.js has no in-memory cache, so every update is a
// fresh read-modify-write).
async function generateDanceVideoViaH3(job, opts = {}) {
  const pollIntervalMs = opts.pollIntervalMs || Number(process.env.GENERATION_POLL_INTERVAL_MS) || 5000;
  try {
    const character = characters.get(job.characterId);
    const garment = garments.get(job.garmentId);
    const danceRef = danceRefs.get(job.refDanceVideoId);
    if (!character || !garment || !danceRef) throw new Error("missing character/garment/dance-ref record");

    if (!job.h3JobId) {
      if (!job.fullPrompt) {
        const built = buildStage2Prompt({ character, garment, danceRef });
        job = generationJobs.update(job.id, { fullPrompt: built.prompt });
      }

      const [characterAssetUrl, garmentAssetUrl, danceRefAssetUrl] = await Promise.all([
        ensureH3AssetUrl(characters, character, "imageUrl"),
        ensureH3AssetUrl(garments, garment, "imageUrl"),
        ensureH3AssetUrl(danceRefs, danceRef, "videoUrl"),
      ]);

      const submitted = await h3ConsoleFetch("/v1/videos", {
        method: "POST",
        body: {
          prompt: job.fullPrompt,
          ...DANCE_GEN_PARAMS,
          reference_image_urls: [characterAssetUrl, garmentAssetUrl],
          reference_video_urls: [danceRefAssetUrl],
        },
      });
      if (!submitted.id) throw new Error(submitted.detail || "submit failed");
      job = generationJobs.update(job.id, { h3JobId: submitted.id, status: "generating" });
    }

    // ponytail: H3's 4 GPUs run one sharded model, not 4 independent
    // workers (H3-CONSOLE.md /v1/status), so a batch of N jobs is served
    // ~serially — the Nth job in queue_position can sit "queued" for
    // N * ~700s before it even starts. A fixed poll-count budget doesn't
    // know about queue depth, so this is wall-clock and generous instead;
    // upgrade path if batches grow past a couple dozen: read `eta_seconds`/
    // `queue_position` off the poll response and size the deadline to that.
    const deadline = Date.now() + (opts.timeoutMs || Number(process.env.GENERATION_TIMEOUT_MS) || 2 * 60 * 60 * 1000);
    while (Date.now() < deadline) {
      await new Promise((r) => setTimeout(r, pollIntervalMs));
      let polled;
      try {
        polled = await h3ConsoleFetch(`/v1/videos/${job.h3JobId}`);
      } catch {
        // A single bad poll (H3 Console hiccup — non-JSON 500 page, dropped
        // connection) isn't a generation failure; the job itself is still
        // fine on H3's side. Skip this tick and retry on the next one,
        // bounded by the same deadline as everything else. Confirmed live
        // 2026-09-02: a 20-job batch's concurrent polling briefly 500'd H3
        // Console, and every job got marked "failed" over a transient
        // response even though H3 still had them queued/running.
        continue;
      }
      if (polled.deleted_at) throw new Error("job was deleted on the H3 console before it finished");
      if (polled.status === "done") {
        const clip = {
          id: polled.id,
          source: "h3console",
          // ingest.js's syncLibrary() only carries an entry forward as-is
          // when `edited` is true — otherwise it rebuilds the record from
          // the raw H3 job on its next periodic sync, which knows nothing
          // about channel/characterId/garmentId/refDanceVideoId and would
          // silently strip them (and leak this clip into the non-dance
          // pickNextClip() pool, since `channel` would be gone too).
          edited: true,
          channel: "dance",
          characterId: job.characterId,
          garmentId: job.garmentId,
          refDanceVideoId: job.refDanceVideoId,
          backend: "h3_console",
          priority: job.priority || "normal",
          requestedByUserId: job.userId || null,
          prompt: `${character.name} × ${garment.name}`,
          fullPrompt: job.fullPrompt,
          width: polled.req.width,
          height: polled.req.height,
          duration: Math.round((polled.req.frames / FPS) * 10) / 10,
          partition: polled.partition,
          likes: 0,
          createdAt: Date.now(),
        };
        const lib = getLibrary();
        lib.push(clip);
        saveLibrary(lib);
        generationJobs.update(job.id, { status: "done", generatedVideoId: clip.id });
        return clip;
      }
      if (polled.status === "error" || polled.status === "failed" || polled.status === "cancelled") {
        throw new Error(polled.error || `generation ${polled.status}`);
      }
    }
    throw new Error("generation timed out");
  } catch (err) {
    generationJobs.update(job.id, { status: "failed", error: err.message });
    throw err;
  }
}

// T33: fal.ai's queue API — submit -> poll .../status -> once COMPLETED,
// fetch .../requests/{id} for the actual result (fal splits status and
// result into two endpoints; H3 Console's single poll returns both at
// once, see generateDanceVideoViaH3 above — genuinely different shapes,
// not just a header swap).
//
// NOT VERIFIED against a real fal account as of this commit — no
// FAL_API_KEY has ever been configured (dev-plan-5.md §1.2 item 2). The
// endpoints/params below come from fal's published docs and the fal-js
// client's own source (see forwardToFalAssets in uploads.js for
// citations), not guesswork — but whether the exact prompt text
// buildStage2Prompt produces (written for and verified against H3
// Console's <Picture N>/<Video N> convention) is interpreted the same way
// by minimax/h3/reference-to-video on fal is an open question (dev-plan-5.md
// §1.2 item 3) only a real call can answer. Also unverified: fal's
// terminal-failure status string(s) — the docs found only named IN_QUEUE/
// IN_PROGRESS/COMPLETED, so this deliberately does NOT guess an error
// enum; a failed fal job surfaces via the existing deadline timeout
// instead of a fast-fail, same conservative tradeoff as a transient poll
// hiccup below.
async function generateDanceVideoViaFal(job, opts = {}) {
  const pollIntervalMs = opts.pollIntervalMs || Number(process.env.GENERATION_POLL_INTERVAL_MS) || 5000;
  try {
    const character = characters.get(job.characterId);
    const garment = garments.get(job.garmentId);
    const danceRef = danceRefs.get(job.refDanceVideoId);
    if (!character || !garment || !danceRef) throw new Error("missing character/garment/dance-ref record");

    if (!job.falRequestId) {
      if (!job.fullPrompt) {
        const built = buildStage2Prompt({ character, garment, danceRef });
        job = generationJobs.update(job.id, { fullPrompt: built.prompt });
      }

      const [characterAssetUrl, garmentAssetUrl, danceRefAssetUrl] = await Promise.all([
        ensureFalAssetUrl(characters, character, "imageUrl"),
        ensureFalAssetUrl(garments, garment, "imageUrl"),
        ensureFalAssetUrl(danceRefs, danceRef, "videoUrl"),
      ]);

      const submitted = await falSubmit({
        prompt: job.fullPrompt,
        duration: 10, // seconds — fal's param is already in seconds, matching our fixed 10s default directly (no /24fps conversion like H3's `frames`)
        resolution: "480P",
        aspect_ratio: "9:16",
        reference_image_urls: [characterAssetUrl, garmentAssetUrl],
        reference_video_urls: [danceRefAssetUrl],
      });
      job = generationJobs.update(job.id, { falRequestId: submitted.request_id, status: "generating" });
    }

    const deadline = Date.now() + (opts.timeoutMs || Number(process.env.GENERATION_TIMEOUT_MS) || 2 * 60 * 60 * 1000);
    while (Date.now() < deadline) {
      await new Promise((r) => setTimeout(r, pollIntervalMs));
      let polled;
      try {
        polled = await falPollStatus(job.falRequestId);
      } catch {
        // Same reasoning as generateDanceVideoViaH3's poll try/catch: a
        // single bad poll isn't a generation failure, retry next tick.
        continue;
      }
      if (polled.status === "COMPLETED") {
        const result = await falFetchResult(job.falRequestId);
        const clip = {
          id: `fal-${job.falRequestId}`,
          source: "fal",
          // Already a public fal CDN URL — /lib/video/:id's existing
          // videoUrl branch (added for "manual" source clips) serves it
          // via redirect directly, no H3-style proxying needed.
          videoUrl: result.video.url,
          edited: true,
          channel: "dance",
          characterId: job.characterId,
          garmentId: job.garmentId,
          refDanceVideoId: job.refDanceVideoId,
          backend: "fal",
          priority: job.priority || "normal",
          requestedByUserId: job.userId || null,
          prompt: `${character.name} × ${garment.name}`,
          fullPrompt: job.fullPrompt,
          // fal's result schema (video.url/content_type/file_name/file_size)
          // doesn't echo back pixel dimensions the way H3 Console's `req`
          // does — these are what we *requested* via resolution/aspect_ratio,
          // not a confirmed readback.
          width: DANCE_GEN_PARAMS.width,
          height: DANCE_GEN_PARAMS.height,
          duration: 10,
          likes: 0,
          createdAt: Date.now(),
        };
        const lib = getLibrary();
        lib.push(clip);
        saveLibrary(lib);
        generationJobs.update(job.id, { status: "done", generatedVideoId: clip.id });
        return clip;
      }
    }
    throw new Error("generation timed out");
  } catch (err) {
    generationJobs.update(job.id, { status: "failed", error: err.message });
    throw err;
  }
}

// Startup recovery, same idea as resumeGenerations() but for generationJobs.
function resumeDressupGenerations() {
  for (const job of generationJobs.list()) {
    if (job.status !== "generating" && job.status !== "queued") continue;
    const inFlightId = job.backend === "fal" ? job.falRequestId : job.h3JobId;
    if (inFlightId) generateDanceVideo(job).catch(() => {});
    else generationJobs.update(job.id, { status: "failed", error: "lost track of this generation across a restart" });
  }
}

// ---- dance.html: one independent playout schedule + free (mode-一/衣柜)
// queue PER CHARACTER ROOM (T11, extended for multi-room 2026-09). Mirrors
// live's pickNextClip/ensureSchedule shape but everything takes the room
// object (getDanceRoom(characterId)) instead of closing over one global
// schedule/queue, and the random-fill pool is that character's own
// channel:"dance" clips only — no cross-character mixing.

// Shared by T34's priorityInbox drain and T39's admin "置顶下一条" pin —
// inserts right after whatever's currently playing (room.schedule[0]),
// pushing every later entry's timing back by this clip's duration rather
// than appending at the tail like the normal fill loop does.
function insertClipNext(room, clip, requestedBy, now) {
  const insertAt = room.schedule.length ? 1 : 0;
  const prevEndAt = insertAt > 0 ? room.schedule[insertAt - 1].endAt : now;
  room.schedule.splice(insertAt, 0, { videoId: clip.id, startAt: prevEndAt, endAt: prevEndAt + clip.duration * 1000, requestedBy: requestedBy || null });
  for (let i = insertAt + 1; i < room.schedule.length; i++) {
    room.schedule[i].startAt += clip.duration * 1000;
    room.schedule[i].endAt += clip.duration * 1000;
  }
}

// T39: admin "暂停自动填充" — freezes only the random-fill loop below (free
// mode-一 content competing for slots) for one room; priorityInbox
// (paid_boost) still drains immediately even while paused, matching
// 需求文档 6.5 节's own framing of "暂停自动填充" as a filler-specific
// control, not a full stop. Per-room set instead of one global flag, same
// reasoning as the schedule/queue split above.
let dancePausedRooms = new Set();

function pickNextDanceClip(characterId, room) {
  const readyIdx = pickBestIndexByStatus(room.queue, "ready");
  if (readyIdx !== -1) {
    const q = room.queue.splice(readyIdx, 1)[0];
    return { videoId: q.videoId, requestedBy: q.nickname };
  }
  // T39: a blacklisted generated_video/character/garment (M.11) is filtered
  // out of the candidate pool — "从排播候选和衣柜列表里过滤掉（不删除记录）".
  // T36's "expired user_paid character drops out of random-fill" is now a
  // whole-room early-exit in ensureRoomSchedule below instead of a per-clip
  // filter here, since the pool is already scoped to one character.
  const pool = getLibrary().filter((c) => {
    if (c.channel !== "dance" || c.characterId !== characterId) return false;
    if (c.qcStatus === "incorrect") return false; // AI 质检没过的片段不进直播间排播候选，但保留在库里
    if (!c.published) return false; // 2026-09 上架/下架: only published clips fill the room on their own
    if (isBlacklisted("generated_video", c.id)) return false;
    if (c.garmentId && isBlacklisted("garment", c.garmentId)) return false;
    return true;
  });
  if (!pool.length) return null;
  const prevVideoId = room.schedule.length ? room.schedule[room.schedule.length - 1].videoId : null;
  const clip = pickLeastPlayedClip(pool, prevVideoId);
  return clip ? { videoId: clip.id, requestedBy: null } : null;
}

function ensureRoomSchedule(characterId, now) {
  const room = getDanceRoom(characterId);
  const character = characters.get(characterId);
  if (isBlacklisted("character", characterId)) return; // T39: blacklisted character's room just stops advancing

  // Reconcile in-flight picks against generationJobs — the store, not an
  // in-memory promise, is the source of truth (T8's resumeDressupGenerations
  // already re-polls H3 for jobs still running after a restart; this tick
  // just needs to notice when they land, restart or not).
  // T34: a paid_boost job landing here gets diverted to priorityInbox
  // instead of "ready" (which would otherwise route it through
  // pickBestIndexByStatus's vote-ranked pick below) — collected here and
  // spliced out of room.queue after the loop rather than mid-iteration,
  // since room.queue is being iterated live.
  const divertedToPriorityInbox = [];
  for (const q of room.queue) {
    if (q.status !== "generating" || !q.jobId) continue;
    const job = generationJobs.get(q.jobId);
    if (!job) continue;
    if (job.status === "done") {
      if (job.priority === "paid_boost") {
        room.priorityInbox.push({ videoId: job.generatedVideoId, requestedBy: q.nickname || null });
        divertedToPriorityInbox.push(q);
      } else {
        q.status = "ready";
        q.videoId = job.generatedVideoId;
      }
    } else if (job.status === "failed") {
      q.status = "failed";
      q.error = job.error;
      q.failedAt = now;
      // T27's paid path (userId/amountPaid only set there — free mode-一
      // picks have neither): refund on generation failure, per "共同后置
      // 流程"'s stated floor. Guarded by an existing-refund lookup rather
      // than trusting this branch only ever runs once — it normally does
      // (room.queue entries only transition "generating" -> "failed" a
      // single time, this loop's own `q.status !== "generating"` guard
      // above prevents re-entry), but a crash between this write and
      // saveDanceState() persisting it could in principle replay the same
      // transition once after restart, and a duplicate refund is real
      // money, not a cosmetic bug.
      if (q.userId && q.amountPaid) {
        const alreadyRefunded = creditLedger.findByRelatedAssetAndReason(q.garmentId, "refund_stage2_fail").length > 0;
        if (!alreadyRefunded) {
          try {
            creditLedger.refund({ userId: q.userId, amount: q.amountPaid, reason: "refund_stage2_fail", relatedAssetId: q.garmentId });
          } catch (err) {
            // NO_SUCH_USER (deleted account) is the only realistic failure
            // here — refund only ever adds, so it can't hit
            // INSUFFICIENT_BALANCE. This branch won't be revisited (the
            // guard above only enters on "generating" -> "failed", a
            // one-time transition), so this is a genuine miss, not a
            // deferred retry — logged rather than silently dropped.
            console.error(`[refund_stage2_fail] failed to refund userId=${q.userId} garmentId=${q.garmentId}: ${err.message}`);
          }
        }
      }
    }
  }

  while (room.schedule.length > 1 && room.schedule[1].endAt <= now) room.schedule.shift();

  // T34: paid_boost content must play "next" (需求文档 3 节: "确定性上镜"),
  // not just "whenever the 30s-ahead fill horizon next needs topping up" —
  // if the schedule is already pre-filled (common: FILLER_DURATION_MS keeps
  // ~30s queued), the fill loop below wouldn't run again for a while and a
  // ready priorityInbox entry could sit for a long time. So this inserts
  // eagerly, right after whatever's currently playing (room.schedule[0],
  // guaranteed accurate now that expired entries were just shifted out
  // above), pushing every later entry's timing back by this clip's
  // duration rather than waiting for its "natural" turn.
  while (room.priorityInbox.length) {
    const next = room.priorityInbox.shift();
    const clip = getLibrary().find((c) => c.id === next.videoId);
    if (!clip) continue; // stale/removed videoId — drop rather than schedule a dead entry
    markPlayed(clip.id);
    consumeCharacterSegment(clip);
    insertClipNext(room, clip, next.requestedBy, now);
  }

  // T36: a user_paid character whose purchased segments have all played
  // (status:"expired") stops random-filling its room entirely — the record
  // and its videos stay in library.json (M.3/M.7: "记录保留"), the room
  // just goes quiet on whatever's left in schedule/priorityInbox.
  const roomExpired = character && character.status === "expired";
  while (!roomExpired && !dancePausedRooms.has(characterId) && (room.schedule.length === 0 || room.schedule[room.schedule.length - 1].endAt < now + FILLER_DURATION_MS)) {
    const picked = pickNextDanceClip(characterId, room);
    if (!picked || !picked.videoId) break;
    const clip = getLibrary().find((c) => c.id === picked.videoId);
    if (!clip) break; // stale/removed videoId — guard rather than schedule a dead entry
    markPlayed(clip.id);
    consumeCharacterSegment(clip);
    const startAt = room.schedule.length ? room.schedule[room.schedule.length - 1].endAt : now;
    room.schedule.push({ videoId: picked.videoId, startAt, endAt: startAt + clip.duration * 1000, requestedBy: picked.requestedBy });
  }
  room.queue = room.queue.filter((q) => !divertedToPriorityInbox.includes(q) && (q.status !== "failed" || now - q.failedAt < FAILED_ENTRY_TTL_MS));

  const viewerMap = getRoomViewers(characterId);
  for (const [cid, lastSeen] of viewerMap) if (now - lastSeen > VIEWER_TTL_MS) viewerMap.delete(cid);
}

function ensureDanceSchedule() {
  const now = Date.now();
  for (const characterId of getDanceRoomCharacterIds()) ensureRoomSchedule(characterId, now);
  saveDanceState();
}
setInterval(ensureDanceSchedule, SCHEDULE_TICK_MS);

http
  .createServer((req, res) => {
    if (req.url.startsWith("/fal/")) {
      const proxyReq = https.request(
        {
          hostname: FAL_HOST,
          path: req.url.slice(4),
          method: req.method,
          headers: { ...req.headers, host: FAL_HOST },
        },
        (proxyRes) => {
          res.writeHead(proxyRes.statusCode, proxyRes.headers);
          proxyRes.pipe(res);
        }
      );
      proxyReq.on("error", (err) => {
        res.writeHead(502, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: { message: err.message } }));
      });
      req.pipe(proxyReq);
      return;
    }

    const pathname = req.url.split("?")[0];

    if (pathname === "/api/admin/login" && req.method === "POST") {
      readJsonBody(req)
        .then((body) => {
          if (!ADMIN_PASSWORD || body.password !== ADMIN_PASSWORD) {
            res.writeHead(401, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "invalid password" }));
            return;
          }
          const token = crypto.randomUUID();
          adminSessions.set(token, Date.now() + ADMIN_SESSION_TTL_MS);
          res.writeHead(200, {
            "Content-Type": "application/json",
            "Set-Cookie": `${ADMIN_SESSION_COOKIE}=${token}; HttpOnly; Path=/; Max-Age=${Math.floor(ADMIN_SESSION_TTL_MS / 1000)}; SameSite=Lax`,
          });
          res.end(JSON.stringify({ ok: true }));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return;
    }

    if (pathname === "/api/admin/logout" && req.method === "POST") {
      const token = parseCookies(req)[ADMIN_SESSION_COOKIE];
      if (token) adminSessions.delete(token);
      res.writeHead(200, {
        "Content-Type": "application/json",
        "Set-Cookie": `${ADMIN_SESSION_COOKIE}=; HttpOnly; Path=/; Max-Age=0`,
      });
      res.end(JSON.stringify({ ok: true }));
      return;
    }

    // Viewer account auth (dev-plan-3.md T19) — entirely separate from the
    // /api/admin/* gate right below. Registering/logging in is always
    // optional: /api/dance/* keeps working on the plain viewer_uid cookie
    // with no session at all (see requireUserSession's doc comment).
    if (pathname === "/api/auth/register" && req.method === "POST") {
      readJsonBody(req)
        .then((body) => {
          const email = (body.email || "").trim().toLowerCase();
          const password = body.password || "";
          if (!/^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(email)) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "invalid email" }));
            return;
          }
          if (password.length < 8) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "password must be at least 8 characters" }));
            return;
          }
          // T21: an existing anonymous viewer_uid/viewer_nickname cookie
          // (set client-side by live.html/dance.html, plaintext, never
          // trusted for anything sensitive) gets carried onto the new
          // account — history isn't rewritten, but future votes/plays from
          // this browser stay attributed to the same identity.
          const existingCookies = parseCookies(req);
          let user;
          try {
            user = userStore.create({
              email,
              passwordHash: hashPassword(password),
              nickname: existingCookies.viewer_nickname || null,
              legacyUid: existingCookies.viewer_uid || null,
            });
          } catch (err) {
            if (err.code === "EMAIL_TAKEN") {
              res.writeHead(409, { "Content-Type": "application/json" });
              res.end(JSON.stringify({ error: "email already registered" }));
              return;
            }
            throw err;
          }
          const session = userSessions.create({ userId: user.id, kind: "session", expiresAt: Date.now() + USER_SESSION_TTL_MS });
          // T20: fire off the verification email. sendVerificationEmail is
          // the entire integration seam — see its own comment.
          const verifySession = userSessions.create({ userId: user.id, kind: "email_verify", expiresAt: Date.now() + EMAIL_VERIFY_TTL_MS });
          const devVerifyUrl = sendVerificationEmail(user.email, verifySession.token);
          const responseBody = { id: user.id, email: user.email, emailVerified: user.emailVerified, nickname: user.nickname };
          if (process.env.NODE_ENV !== "production") responseBody.devVerifyUrl = devVerifyUrl;
          res.writeHead(200, {
            "Content-Type": "application/json",
            "Set-Cookie": `${USER_SESSION_COOKIE}=${session.token}; HttpOnly; Path=/; Max-Age=${Math.floor(USER_SESSION_TTL_MS / 1000)}; SameSite=Lax`,
          });
          res.end(JSON.stringify(responseBody));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return;
    }

    if (pathname === "/api/auth/login" && req.method === "POST") {
      readJsonBody(req)
        .then((body) => {
          const email = (body.email || "").trim().toLowerCase();
          const password = body.password || "";
          const user = userStore.findByEmail(email);
          // Deliberately the same error for "no such email" and "wrong
          // password" — distinguishing the two lets an attacker enumerate
          // which emails are registered.
          if (!user || !verifyPassword(password, user.passwordHash)) {
            res.writeHead(401, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "invalid email or password" }));
            return;
          }
          const session = userSessions.create({ userId: user.id, kind: "session", expiresAt: Date.now() + USER_SESSION_TTL_MS });
          const setCookies = [`${USER_SESSION_COOKIE}=${session.token}; HttpOnly; Path=/; Max-Age=${Math.floor(USER_SESSION_TTL_MS / 1000)}; SameSite=Lax`];
          // T21: push the account's bound identity back onto this browser,
          // even if it showed up with no viewer_uid cookie at all or a
          // fresh one from a different device — otherwise logging in from
          // a clean browser would silently start a new anonymous identity,
          // which for anything vote-limited defeats the point of binding
          // it to an account in the first place.
          if (user.legacyUid) setCookies.push(viewerIdentityCookie("viewer_uid", user.legacyUid));
          if (user.nickname) setCookies.push(viewerIdentityCookie("viewer_nickname", user.nickname));
          res.writeHead(200, { "Content-Type": "application/json", "Set-Cookie": setCookies });
          res.end(JSON.stringify({ id: user.id, email: user.email, emailVerified: user.emailVerified, nickname: user.nickname }));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return;
    }

    // T20: single-use — the email_verify session is revoked on success, so
    // a second visit to the same link (or an expired one) hits the same
    // "invalid or expired" error rather than silently re-succeeding.
    if (pathname === "/api/auth/verify" && req.method === "GET") {
      const params = new URLSearchParams(req.url.split("?")[1] || "");
      const token = params.get("token") || "";
      const verifySession = userSessions.findByToken(token);
      if (!verifySession || verifySession.kind !== "email_verify") {
        res.writeHead(400, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "invalid or expired verification link" }));
        return;
      }
      userStore.update(verifySession.userId, { emailVerified: true });
      userSessions.revoke(token);
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(JSON.stringify({ ok: true }));
      return;
    }

    if (pathname === "/api/auth/logout" && req.method === "POST") {
      const token = parseCookies(req)[USER_SESSION_COOKIE];
      if (token) userSessions.revoke(token);
      res.writeHead(200, {
        "Content-Type": "application/json",
        "Set-Cookie": `${USER_SESSION_COOKIE}=; HttpOnly; Path=/; Max-Age=0`,
      });
      res.end(JSON.stringify({ ok: true }));
      return;
    }

    // Debug-only endpoint, per T19's own acceptance criteria — fine to
    // keep past this task too (a real account page will want it), but
    // intentionally minimal for now.
    if (pathname === "/api/auth/me" && req.method === "GET") {
      const user = requireUserSession(req);
      if (!user) {
        res.writeHead(401, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "unauthorized" }));
        return;
      }
      res.writeHead(200, { "Content-Type": "application/json" });
      // creditBalance riding along here (T29) rather than a dedicated
      // /api/credits/balance endpoint — it's the same "logged-in user's own
      // state" this route already exists to serve, and refreshAuthState()
      // in live.html/dance.html (T22) already polls this after every login.
      res.end(JSON.stringify({ id: user.id, email: user.email, emailVerified: user.emailVerified, nickname: user.nickname, creditBalance: user.creditBalance }));
      return;
    }

    // T24: credit topup. Login + emailVerified matches M.10's "任何扣积分/
    // 写用户资产的接口" rule — a topup adds money rather than spending it,
    // but still needs an accountable identity before a real charge runs.
    if (pathname === "/api/credits/checkout" && req.method === "POST") {
      const user = requireUserSession(req);
      if (!user) {
        res.writeHead(401, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "login required" }));
        return;
      }
      if (!user.emailVerified) {
        res.writeHead(403, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "email verification required before purchasing credits" }));
        return;
      }
      readJsonBody(req)
        .then(async (body) => {
          try {
            const session = await createCheckoutSession({ userId: user.id, tierKey: (body.tierKey || "").trim() });
            res.writeHead(200, { "Content-Type": "application/json" });
            res.end(JSON.stringify(session));
          } catch (err) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: err.message }));
          }
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return;
    }

    // Dev-only completion of a mock checkout created above — simulates the
    // browser landing back from Stripe's hosted page after a successful
    // payment. Only ever reachable via a token this same process handed
    // out (createMockCheckoutUrl), so there's nothing to authenticate here
    // beyond "does this token exist and is it unused."
    if (pathname === "/api/credits/mock-checkout" && req.method === "GET") {
      const token = new URL(req.url, "http://x").searchParams.get("token") || "";
      const pending = pendingMockCheckouts.get(token);
      pendingMockCheckouts.delete(token); // single-use, same spirit as T20's email-verify tokens
      if (!pending || pending.expiresAt < Date.now()) {
        res.writeHead(400, { "Content-Type": "text/plain" });
        res.end("invalid or expired mock checkout token");
        return;
      }
      try {
        completeTopup({ userId: pending.userId, tierKey: pending.tierKey, paymentRef: `mock_${token}` });
        res.writeHead(302, { Location: "/dance.html?topup=success" });
        res.end();
      } catch (err) {
        res.writeHead(400, { "Content-Type": "text/plain" });
        res.end(err.message);
      }
      return;
    }

    // Real Stripe webhook — only meaningful once a real
    // STRIPE_WEBHOOK_SECRET is configured (tomorrow, per the user).
    // Refuses anything it can't verify rather than trusting an
    // unsigned/unverifiable request, even before a secret exists
    // (dev-plan-4.md T24's explicit acceptance criterion).
    if (pathname === "/api/credits/webhook" && req.method === "POST") {
      readRawTextBody(req)
        .then((rawBody) => {
          if (!STRIPE_WEBHOOK_SECRET || !verifyStripeWebhookSignature(rawBody, req.headers["stripe-signature"], STRIPE_WEBHOOK_SECRET)) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "signature verification failed" }));
            return;
          }
          let event;
          try {
            event = JSON.parse(rawBody);
          } catch {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "invalid JSON" }));
            return;
          }
          if (event.type === "checkout.session.completed") {
            const session = event.data.object;
            try {
              // event.id, not session.id: Stripe's at-least-once
              // redelivery resends the same event id for the same
              // occurrence, which is exactly what topup()'s paymentRef
              // dedup (db.js) keys on.
              completeTopup({ userId: session.metadata.userId, tierKey: session.metadata.tierKey, paymentRef: event.id });
            } catch (err) {
              // Already-applied duplicates are handled inside topup()
              // itself (returns the existing row, doesn't throw) — a throw
              // here means something genuinely went wrong (unknown tier,
              // missing user), not a benign redelivery.
              res.writeHead(400, { "Content-Type": "application/json" });
              res.end(JSON.stringify({ error: err.message }));
              return;
            }
          }
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ received: true }));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "failed to read request body" }));
        });
      return;
    }

    if (pathname.startsWith("/api/admin/") && !isAdminAuthed(req)) {
      res.writeHead(401, { "Content-Type": "application/json" });
      res.end(JSON.stringify({ error: "unauthorized" }));
      return;
    }

    if (charactersCrud(pathname, req, res)) return;
    if (characterImagesCrud(pathname, req, res)) return;
    if (garmentsCrud(pathname, req, res)) return;
    if (danceRefsCrud(pathname, req, res)) return;

    // Standalone "人衣图生成" admin tool (admin-dressgen.html +
    // admin-dressgen-task.html): up to 6 person reference photos
    // (full-body/face × front/side/back, however many are actually
    // uploaded) + 1 garment image (a) -> 3 new full-body images of that
    // person wearing the garment, one per view (c), generated by 3
    // sequential gpt-image-2 calls. This is a real background task, not a
    // blocking request: POST creates the row (status "queued") and returns
    // its id immediately, then runDressGenViews() runs fire-and-forget —
    // the 3 upstream calls take ~70s+ each (CODEX-IMAGEGEN.md), so blocking
    // the HTTP response on all 3 sequentially risked a front-end proxy
    // timing the request out (a real 502 was hit doing exactly this before
    // this was made async). The client polls GET /dressgen (list) or
    // GET /dressgen/:id (task detail) to watch it progress. See
    // generateDressImage()'s doc comment for the vendor contract this
    // assumes, and DRESSGEN_PERSON_SLOTS above for why one call gets every
    // uploaded person image rather than a fixed per-view pairing.
    if (pathname === "/api/admin/dressgen/prompts" && req.method === "GET") {
      const prompts = {};
      DRESSGEN_VIEWS.forEach((view) => (prompts[view] = defaultDressgenPrompt(view)));
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(JSON.stringify(prompts));
      return;
    }
    if (pathname === "/api/admin/dressgen" && req.method === "GET") {
      // Paginated (2026-09-03) — store.list()/dress-gen.json is a
      // full-file read (store.js's own doc comment), fine today at a
      // handful of records but not something to keep shipping whole to
      // the browser as it grows. Newest-first, same order the frontend
      // used to produce itself via .slice().reverse().
      const params = new URL(req.url, "http://x").searchParams;
      const page = Math.max(1, Number(params.get("page")) || 1);
      const pageSize = Math.min(100, Math.max(1, Number(params.get("pageSize")) || 20));
      const all = dressGenRecords.list().slice().reverse();
      const items = all.slice((page - 1) * pageSize, page * pageSize);
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(JSON.stringify({ items, total: all.length, page, pageSize }));
      return;
    }
    if (pathname === "/api/admin/dressgen" && req.method === "POST") {
      readJsonBody(req)
        .then((body) => {
          if (typeof body.garmentImage !== "string" || !body.garmentImage.startsWith("/uploads/")) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "garmentImage must be a /uploads/... path from POST /api/admin/upload" }));
            return;
          }
          const providedPersonSlots = DRESSGEN_PERSON_SLOTS.filter((f) => typeof body[f] === "string" && body[f]);
          const badSlot = providedPersonSlots.find((f) => !body[f].startsWith("/uploads/"));
          if (badSlot) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: `${badSlot} must be a /uploads/... path from POST /api/admin/upload` }));
            return;
          }
          if (providedPersonSlots.length === 0) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "at least one person reference image is required (upload as many of the 6 as you have)" }));
            return;
          }
          const provider = DRESSGEN_PROVIDERS.includes(body.provider) ? body.provider : DRESSGEN_DEFAULT_PROVIDER;
          const missingKey = dressGenProviderKeyMissing(provider);
          if (missingKey) {
            res.writeHead(500, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: missingKey }));
            return;
          }

          const prompts = {};
          for (const view of DRESSGEN_VIEWS) {
            const custom = body.prompts && typeof body.prompts[view] === "string" ? body.prompts[view].trim() : "";
            prompts[view] = custom || defaultDressgenPrompt(view);
          }

          const record = { garmentImage: body.garmentImage, prompts, provider };
          for (const slot of DRESSGEN_PERSON_SLOTS) record[slot] = body[slot] || null;
          record.status = "queued";
          record.viewStatus = { front: "queued", side: "queued", back: "queued" };
          record.outputImages = { front: null, side: null, back: null };
          record.errors = { front: null, side: null, back: null };
          record.viewProvider = { front: null, side: null, back: null };

          const entry = dressGenRecords.create(record);
          runDressGenViews(entry.id, dressGenImageAbsPaths(entry), DRESSGEN_VIEWS).catch(() => {});
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify(entry));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return;
    }
    // Retry: reuses the row's own stored images/prompts — no re-upload, no
    // re-typing a prompt (that was an explicit ask: a failed task should be
    // re-runnable with one click). Whole-task retry only reprocesses views
    // that don't already have an output (so a "partial" task doesn't redo
    // the view(s) that already succeeded); per-view retry
    // (POST .../:id/retry/:view) reprocesses exactly the one view clicked,
    // for admin-dressgen-task.html's "regenerate just this image" button.
    if (/^\/api\/admin\/dressgen\/[^/]+\/retry\/(front|side|back)$/.test(pathname) && req.method === "POST") {
      const [, id, view] = pathname.match(/^\/api\/admin\/dressgen\/([^/]+)\/retry\/(front|side|back)$/);
      const record = dressGenRecords.get(id);
      if (!record) {
        res.writeHead(404, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "not found" }));
        return;
      }
      readJsonBody(req)
        .catch(() => ({})) // an empty/absent body is fine — retry with the stored prompt/provider as-is
        .then((body) => {
          // admin-dressgen-task.html's per-image "edit prompt then
          // regenerate" flow: an optional prompt override for just this
          // view, persisted so the record keeps reflecting what was
          // actually sent. Same for an optional provider override — e.g.
          // switching a view that failed on image2 over to wavespeed
          // instead, an explicit admin choice per the note above
          // generateDressImage, not an automatic fallback.
          const promptOverride = typeof body.prompt === "string" && body.prompt.trim() ? body.prompt.trim() : null;
          const provider = DRESSGEN_PROVIDERS.includes(body.provider) ? body.provider : record.provider || DRESSGEN_DEFAULT_PROVIDER;
          const missingKey = dressGenProviderKeyMissing(provider);
          if (missingKey) {
            res.writeHead(500, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: missingKey }));
            return;
          }
          const updated = dressGenRecords.update(id, {
            status: "generating",
            provider,
            viewStatus: { ...record.viewStatus, [view]: "queued" },
            prompts: promptOverride ? { ...record.prompts, [view]: promptOverride } : record.prompts,
          });
          runDressGenViews(id, dressGenImageAbsPaths(updated), [view]).catch(() => {});
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify(updated));
        });
      return;
    }
    if (/^\/api\/admin\/dressgen\/[^/]+\/retry$/.test(pathname) && req.method === "POST") {
      const id = pathname.slice("/api/admin/dressgen/".length, -"/retry".length);
      const record = dressGenRecords.get(id);
      if (!record) {
        res.writeHead(404, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "not found" }));
        return;
      }
      readJsonBody(req)
        .catch(() => ({})) // an empty/absent body is fine — retry with the stored provider as-is
        .then((body) => {
          // Optional provider override, same as per-view retry above — an
          // explicit admin choice (e.g. image2 failed, switch to
          // wavespeed), not an automatic fallback.
          const provider = DRESSGEN_PROVIDERS.includes(body.provider) ? body.provider : record.provider || DRESSGEN_DEFAULT_PROVIDER;
          const missingKey = dressGenProviderKeyMissing(provider);
          if (missingKey) {
            res.writeHead(500, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: missingKey }));
            return;
          }
          const viewsToRetry = DRESSGEN_VIEWS.filter((v) => !record.outputImages[v]);
          if (viewsToRetry.length === 0) {
            res.writeHead(200, { "Content-Type": "application/json" });
            res.end(JSON.stringify(record)); // already fully done — nothing to retry
            return;
          }
          const viewStatus = { ...record.viewStatus };
          viewsToRetry.forEach((v) => (viewStatus[v] = "queued"));
          const updated = dressGenRecords.update(id, { status: "generating", provider, viewStatus });
          runDressGenViews(id, dressGenImageAbsPaths(updated), viewsToRetry).catch(() => {});
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify(updated));
        });
      return;
    }
    if (pathname.startsWith("/api/admin/dressgen/") && req.method === "DELETE") {
      const removed = dressGenRecords.remove(pathname.slice("/api/admin/dressgen/".length));
      res.writeHead(removed ? 200 : 404, { "Content-Type": "application/json" });
      res.end(JSON.stringify({ deleted: removed }));
      return;
    }
    if (pathname.startsWith("/api/admin/dressgen/") && req.method === "GET") {
      const record = dressGenRecords.get(pathname.slice("/api/admin/dressgen/".length));
      res.writeHead(record ? 200 : 404, { "Content-Type": "application/json" });
      res.end(JSON.stringify(record || { error: "not found" }));
      return;
    }

    // T30: manual balance correction, e.g. a support gesture ("sorry about
    // the failed generation that didn't auto-refund, here's some credits")
    // or clawing back an abused promo. Always attributable — see
    // adminActorUserId's doc comment.
    if (pathname === "/api/admin/credit/adjust" && req.method === "POST") {
      readJsonBody(req)
        .then((body) => {
          const userId = (body.userId || "").trim();
          const delta = Number(body.delta);
          if (!userId || !userStore.get(userId) || !Number.isFinite(delta) || delta === 0) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "userId (must reference an existing user) and a non-zero numeric delta are required" }));
            return;
          }
          try {
            const row = creditLedger.adjust({ userId, delta, reason: (body.reason || "admin_adjust").trim(), actorUserId: adminActorUserId(req) });
            res.writeHead(200, { "Content-Type": "application/json" });
            res.end(JSON.stringify(row));
          } catch (err) {
            const status = err.code === "INSUFFICIENT_BALANCE" ? 400 : 500;
            res.writeHead(status, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: err.message }));
          }
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return;
    }

    // T39 (M.11): 运营手工拉黑. 拦截点在提交类接口自身
    // (/api/dance/pick、两个 upload——见各自的 isBlacklisted 调用)，这里
    // 只是维护这张表.
    if (pathname === "/api/admin/blacklist" && req.method === "GET") {
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(JSON.stringify(blacklist.list()));
      return;
    }
    if (pathname === "/api/admin/blacklist" && req.method === "POST") {
      readJsonBody(req)
        .then((body) => {
          const targetType = (body.targetType || "").trim();
          const targetId = (body.targetId || "").trim();
          const validTypes = ["user", "character", "garment", "generated_video", "ip"];
          if (!validTypes.includes(targetType) || !targetId) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: `targetType must be one of ${validTypes.join("/")}, targetId is required` }));
            return;
          }
          const entry = blacklist.create({ targetType, targetId, reason: (body.reason || "").trim(), createdBy: adminActorUserId(req) });
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify(entry));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return;
    }
    if (pathname.startsWith("/api/admin/blacklist/") && req.method === "DELETE") {
      const removed = blacklist.remove(pathname.slice("/api/admin/blacklist/".length));
      res.writeHead(removed ? 200 : 404, { "Content-Type": "application/json" });
      res.end(JSON.stringify({ deleted: removed }));
      return;
    }

    // T39 (需求文档 6.5 节): dance.html 播放管理——插播/置顶、跳过当前、
    // 暂停/恢复自动填充.
    if (pathname === "/api/admin/dance/schedule/pin" && req.method === "POST") {
      readJsonBody(req)
        .then((body) => {
          const clip = getLibrary().find((c) => c.id === body.videoId && c.channel === "dance");
          if (!clip || !clip.characterId) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "videoId must reference an existing dance clip with a character (a room to pin it into)" }));
            return;
          }
          ensureDanceSchedule(); // settle any pending state before splicing
          const room = getDanceRoom(clip.characterId);
          insertClipNext(room, clip, "管理员置顶", Date.now());
          saveDanceState();
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ ok: true, characterId: clip.characterId, schedule: room.schedule }));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return;
    }
    if (pathname === "/api/admin/dance/schedule/skip" && req.method === "POST") {
      const characterId = new URL(req.url, "http://x").searchParams.get("characterId");
      if (!characterId || !characters.get(characterId)) {
        res.writeHead(400, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "characterId query param must reference an existing character" }));
        return;
      }
      ensureDanceSchedule();
      const room = getDanceRoom(characterId);
      if (room.schedule.length > 1) {
        room.schedule.shift(); // next tick's own "shift expired entries" step will pick up the new current from here
      } else if (room.schedule.length === 1) {
        room.schedule[0].endAt = Date.now(); // nothing queued behind it — force it to expire now, next tick fills a replacement
      }
      ensureDanceSchedule(); // fill immediately rather than waiting up to SCHEDULE_TICK_MS
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(JSON.stringify({ ok: true, schedule: room.schedule }));
      return;
    }
    if (pathname === "/api/admin/dance/pause" && req.method === "POST") {
      readJsonBody(req)
        .then((body) => {
          if (!body.characterId || !characters.get(body.characterId)) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "characterId must reference an existing character" }));
            return;
          }
          if (body.paused) dancePausedRooms.add(body.characterId);
          else dancePausedRooms.delete(body.characterId);
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ characterId: body.characterId, paused: dancePausedRooms.has(body.characterId) }));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return;
    }

    if (pathname === "/api/admin/generate" && req.method === "GET") {
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(JSON.stringify(generationJobs.list()));
      return;
    }

    if (pathname === "/api/admin/generate" && req.method === "POST") {
      readJsonBody(req)
        .then((body) => {
          const { status, body: respBody } = submitGeneration(body);
          res.writeHead(status, { "Content-Type": "application/json" });
          res.end(JSON.stringify(respBody));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return;
    }

    if (pathname.startsWith("/api/admin/generate/") && req.method === "GET") {
      const job = generationJobs.get(pathname.slice("/api/admin/generate/".length));
      if (!job) {
        res.writeHead(404, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "not found" }));
        return;
      }
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(JSON.stringify(job));
      return;
    }

    // T9 冷启动批量生成：{characterId, garmentIds[], refDanceVideoIds?[]}.
    // No refDanceVideoIds given -> one job per garment, each with its own
    // random active dance-ref (same as the single-generate default).
    // refDanceVideoIds given -> full garmentIds x refDanceVideoIds cross
    // product, so an operator can pin specific reference dances.
    // Every combo goes through submitGeneration, so the M.7 dedupe cache
    // (same characterId+garmentId already generated) is honored per combo,
    // not just per batch.
    if (pathname === "/api/admin/batch-gen" && req.method === "POST") {
      readJsonBody(req)
        .then((body) => {
          const { characterId, garmentIds, refDanceVideoIds } = body;
          if (!characters.get(characterId) || !Array.isArray(garmentIds) || garmentIds.length === 0) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "characterId must exist and garmentIds must be a non-empty array" }));
            return;
          }
          const batchId = crypto.randomUUID();
          const refCombos = Array.isArray(refDanceVideoIds) && refDanceVideoIds.length > 0 ? refDanceVideoIds : [undefined];
          const results = [];
          for (const garmentId of garmentIds) {
            for (const refDanceVideoId of refCombos) {
              const { status, body: respBody } = submitGeneration({ characterId, garmentId, refDanceVideoId, batchId });
              results.push({ garmentId, refDanceVideoId: refDanceVideoId || null, status, ...respBody });
            }
          }
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ batchId, results }));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return;
    }

    if (pathname === "/api/admin/batch-gen/status" && req.method === "GET") {
      const batchId = new URL(req.url, "http://x").searchParams.get("batchId");
      if (!batchId) {
        res.writeHead(400, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "batchId query param required" }));
        return;
      }
      const jobs = generationJobs.list().filter((j) => j.batchId === batchId);
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(JSON.stringify(jobs));
      return;
    }

    // ---- dance.html: public viewer-facing endpoints (T11/T12/T15/T17) ----
    // No admin auth (T6 only gates /api/admin/*) — these are the free,
    // anonymous, 模式一 (衣柜选衣服) path. 模式二/三 (T27/T35, below) each
    // require login+emailVerified on their own.

    // One live room per character (2026-09): a room exists for every
    // character with >=1 generated dance video — no separate publish
    // toggle. Room list page polls this for its "直播间列表".
    if (pathname === "/api/dance/rooms" && req.method === "GET") {
      ensureDanceSchedule(); // settle viewer TTL cleanup before reporting counts, and fill each room's schedule
      const now = Date.now();
      const rooms = [...getDanceRoomCharacterIds()]
        .filter((id) => !isBlacklisted("character", id))
        .map((id) => characters.get(id))
        .filter((c) => c && c.status !== "expired")
        .map((c) => {
          const room = getDanceRoom(c.id);
          let idx = room.schedule.findIndex((s) => s.startAt <= now && now < s.endAt);
          if (idx === -1) idx = room.schedule.length - 1;
          const current = room.schedule[idx];
          return {
            id: c.id,
            name: c.name,
            imageUrl: c.imageUrl,
            appearanceDescriptor: c.appearanceDescriptor,
            watching: getRoomViewers(c.id).size,
            // the room list card previews this room's actual dance video,
            // not just the character's static reference photo
            previewVideoId: current ? current.videoId : null,
          };
        });
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(JSON.stringify(rooms));
      return;
    }

    // Per-room wardrobe/待选衣服列表: only garments THIS character already
    // has a generated video for (findExistingGeneratedVideo's (characterId,
    // garmentId) index — the same M.7 dedupe granularity), shuffled — this
    // is a "pick what she's already worn" list, not a request-anything
    // catalog, and viewers shouldn't see the same fixed order every visit.
    if (pathname === "/api/dance/wardrobe" && req.method === "GET") {
      const characterId = new URL(req.url, "http://x").searchParams.get("characterId");
      if (!characterId || !characters.get(characterId)) {
        res.writeHead(400, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "characterId query param must reference an existing character" }));
        return;
      }
      const garmentIdsWithVideo = new Set(
        getLibrary()
          .filter((c) => c.channel === "dance" && c.characterId === characterId && c.qcStatus !== "incorrect")
          .map((c) => c.garmentId)
      );
      const list = garments.list().filter((g) => g.isActive && garmentIdsWithVideo.has(g.id) && !isBlacklisted("garment", g.id));
      for (let i = list.length - 1; i > 0; i--) {
        const j = Math.floor(Math.random() * (i + 1));
        [list[i], list[j]] = [list[j], list[i]];
      }
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(JSON.stringify(list));
      return;
    }

    // T28/T29 need pricing (spend_garment's cost, topup_tier options) on
    // the client before any purchase decision — public/unauthenticated on
    // purpose, same reasoning as GET /api/dance/wardrobe above.
    if (pathname === "/api/pricing" && req.method === "GET") {
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(JSON.stringify(pricing.list().filter((p) => p.isActive)));
      return;
    }

    if (pathname === "/api/dance/live/state" && req.method === "GET") {
      const params = new URL(req.url, "http://x").searchParams;
      const characterId = params.get("characterId");
      if (!characterId || !characters.get(characterId)) {
        res.writeHead(400, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "characterId query param must reference an existing character" }));
        return;
      }
      ensureDanceSchedule();
      const now = Date.now();
      const cid = params.get("cid");
      const uid = params.get("uid") || null;
      if (cid) getRoomViewers(characterId).set(cid, now);
      const room = getDanceRoom(characterId);
      let idx = room.schedule.findIndex((s) => s.startAt <= now && now < s.endAt);
      if (idx === -1) idx = room.schedule.length - 1;
      const cur = room.schedule[idx];
      const lib = getLibrary();
      const joinClip = (videoId) => lib.find((c) => c.id === videoId) || null;
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(
        JSON.stringify({
          now,
          watching: getRoomViewers(characterId).size,
          current: cur ? { clip: joinClip(cur.videoId), startAt: cur.startAt, endAt: cur.endAt, requestedBy: cur.requestedBy || null } : null,
          upNext: room.schedule.slice(idx + 1, idx + 4).map((s) => ({ ...(joinClip(s.videoId) || {}), requestedBy: s.requestedBy || null })),
          queue: room.queue
            .filter((q) => ["generating", "failed"].includes(q.status))
            .slice()
            .sort((a, b) => voteCount(b) - voteCount(a))
            .map((q) => ({
              id: q.id,
              garmentId: q.garmentId,
              nickname: q.nickname,
              status: q.status,
              error: q.error,
              votes: voteCount(q),
              voted: uid ? (q.votes || []).includes(uid) : false,
            })),
        })
      );
      return;
    }

    // 模式一：{characterId, garmentId, nickname?} — which room, and which of
    // that room's already-rendered garments (GET /api/dance/wardrobe above
    // already restricts the choices to that pair, so this is always a cache
    // hit through submitGeneration's M.7 dedupe, never a fresh generation).
    // 3.1 节: 免费用户不能指定/上传人物 still holds — you can only dress the
    // room's own character, not switch her out.
    if (pathname === "/api/dance/pick" && req.method === "POST") {
      readJsonBody(req)
        .then((body) => {
          const character = characters.get(body.characterId);
          if (!character) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "characterId must reference an existing character" }));
            return;
          }
          const garment = garments.get(body.garmentId);
          if (!garment || !garment.isActive) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "garmentId must reference an active garment" }));
            return;
          }
          // T39 (M.11): a blacklisted garment is rejected at the submission
          // entry point itself — "不进流水线、不扣积分" (moot here, mode 1
          // is free, but the entry-point rejection still applies).
          if (isBlacklisted("garment", garment.id)) {
            res.writeHead(403, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "this garment is unavailable" }));
            return;
          }
          const { status, body: respBody } = submitGeneration({ characterId: character.id, garmentId: garment.id });
          if (status !== 200) {
            res.writeHead(status, { "Content-Type": "application/json" });
            res.end(JSON.stringify(respBody));
            return;
          }
          const entry = {
            id: crypto.randomUUID(),
            garmentId: garment.id,
            characterId: character.id,
            nickname: (body.nickname || "").trim() || null,
            submittedAt: Date.now(),
            votes: [],
          };
          if (respBody.cached) {
            entry.status = "ready";
            entry.videoId = respBody.clip.id;
          } else {
            entry.status = "generating";
            entry.jobId = respBody.jobId;
          }
          getDanceRoom(character.id).queue.push(entry);
          saveDanceState();
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ status: entry.status, id: entry.id, videoId: entry.videoId || null }));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return;
    }

    // T38 (dev-plan-5.md): "我的作品" — 需求文档 7.4 节: expired/下线的
    // user_paid characters (T36) and their videos must stay individually
    // retrievable by their owner, "下线=不再出现在公开直播间和其他人的
    // 衣柜/随机池里"，不是"下线=消失". Login required, no emailVerified
    // gate — this is a read of your own past purchases, not a new spend.
    if (pathname === "/api/dance/my-works" && req.method === "GET") {
      const user = requireUserSession(req);
      if (!user) {
        res.writeHead(401, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "login required" }));
        return;
      }
      const lib = getLibrary();
      const myCharacters = characters.list().filter((c) => c.ownerUserId === user.id);
      const myGarments = garments.list().filter((g) => g.ownerUserId === user.id);
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(
        JSON.stringify({
          characters: myCharacters.map((c) => ({ ...c, videos: lib.filter((clip) => clip.characterId === c.id) })),
          garments: myGarments.map((g) => ({ ...g, videos: lib.filter((clip) => clip.garmentId === g.id) })),
        })
      );
      return;
    }

    // T27 模式二: 付费传衣服. 需登录 + emailVerified (M.10). Order matters —
    // moderation runs before any garments record or spend exists (a
    // rejected upload leaves nothing behind); the garment record is
    // created before spend so the ledger row can carry relatedAssetId, and
    // is rolled back (garments.remove) if the spend or the generation
    // submission itself fails, so a failed/rejected attempt never leaves a
    // phantom garment in the library. Async generation failures (after
    // this handler has already responded) are refunded from
    // ensureDanceSchedule's tick instead — see its own comment.
    if (pathname === "/api/dance/upload-garment" && req.method === "POST") {
      const user = requireUserSession(req);
      if (!user) {
        res.writeHead(401, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "login required" }));
        return;
      }
      if (!user.emailVerified) {
        res.writeHead(403, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "email verification required before uploading a garment" }));
        return;
      }
      // T39 (M.11): a blacklisted account is rejected at the submission
      // entry point — "不进流水线、不扣积分".
      if (isBlacklisted("user", user.id)) {
        res.writeHead(403, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "account unavailable" }));
        return;
      }
      const boundary = boundaryFromContentType(req.headers["content-type"] || "");
      if (!boundary) {
        res.writeHead(400, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "expected multipart/form-data" }));
        return;
      }
      readRawBody(req)
        .then(async (raw) => {
          const parts = parseMultipart(raw, boundary);
          const filePart = parts.find((p) => p.name === "file");
          if (!filePart) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "missing file field" }));
            return;
          }
          const sniffed = sniffImageType(filePart.data);
          if (!sniffed) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "unrecognized image type (expected jpeg/png/webp)" }));
            return;
          }
          // Which room you're uploading from — the garment still joins the
          // global wardrobe pool once generated (every room can pick it
          // later), but the upload itself dresses THIS room's character
          // first (confirmed: "上传衣服=全局衣柜，所有房间都能选").
          const characterIdPart = parts.find((p) => p.name === "characterId");
          const targetCharacter = characterIdPart ? characters.get(characterIdPart.data.toString("utf8").trim()) : null;
          if (!targetCharacter) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "characterId must reference an existing character (which room you're in)" }));
            return;
          }

          let relPath, absPath;
          try {
            ({ relPath } = stripMetadataAndSave(filePart.data, sniffed));
            absPath = path.join(__dirname, relPath);
          } catch {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "failed to process image" }));
            return;
          }

          const moderation = await moderateGarmentImage(absPath, relPath);
          if (!moderation.approved) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "image rejected by moderation", reason: moderation.reason }));
            return;
          }

          const appearanceDescriptor = await describeGarmentImage(absPath);
          const garment = garments.create({
            name: `${user.nickname || user.email.split("@")[0]} 上传`,
            category: "",
            thumbnailUrl: relPath,
            imageUrl: relPath,
            appearanceDescriptor,
            source: "user_paid",
            ownerUserId: user.id,
            moderationStatus: "approved",
            isActive: true,
          });

          const spendGarment = pricing.get("spend_garment");
          const amount = spendGarment ? spendGarment.credits : 0;
          let spendRow;
          try {
            spendRow = creditLedger.spend({ userId: user.id, amount, reason: "spend_garment", relatedAssetId: garment.id });
          } catch (err) {
            garments.remove(garment.id);
            const status = err.code === "INSUFFICIENT_BALANCE" ? 402 : 500;
            res.writeHead(status, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: err.message }));
            return;
          }

          // userId (T33): mode 2 is a paid request, so this both fixes M.7's
          // requestedByUserId tracking (previously always null — a gap left
          // over from T27) and makes it fal-eligible once FAL_API_KEY is
          // configured. priority stays "normal" (T27/dev-plan-4.md's
          // explicit scope: only mode 3 skips voting, mode 2 doesn't).
          const { status, body: respBody } = submitGeneration({ characterId: targetCharacter.id, garmentId: garment.id, userId: user.id });
          if (status !== 200) {
            creditLedger.refund({ userId: user.id, amount, reason: "refund_stage2_fail", relatedAssetId: garment.id });
            garments.remove(garment.id);
            res.writeHead(status, { "Content-Type": "application/json" });
            res.end(JSON.stringify(respBody));
            return;
          }

          const entry = {
            id: crypto.randomUUID(),
            garmentId: garment.id,
            characterId: targetCharacter.id,
            nickname: user.nickname || null,
            userId: user.id,
            amountPaid: amount,
            submittedAt: Date.now(),
            votes: [],
          };
          if (respBody.cached) {
            entry.status = "ready";
            entry.videoId = respBody.clip.id;
          } else {
            entry.status = "generating";
            entry.jobId = respBody.jobId;
          }
          getDanceRoom(targetCharacter.id).queue.push(entry);
          saveDanceState();
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ status: entry.status, id: entry.id, garmentId: garment.id, videoId: entry.videoId || null, creditsSpent: amount, balanceAfter: spendRow.balanceAfter }));
        })
        .catch((err) => {
          if (res.writableEnded) return;
          const status = err.code === "PAYLOAD_TOO_LARGE" ? 413 : 400;
          res.writeHead(status, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: err.message || "upload failed" }));
        });
      return;
    }

    // T35 模式三: 付费传人物 (dev-plan-5.md). 需登录 + emailVerified, same
    // rule as T27. Differs from T27 in three structural ways: (1) the
    // upload itself becomes the new characters record (not paired with an
    // existing default character — garment is what's optional/random here,
    //需求文档 3.3 第 4 点); (2) cost scales with how many 10s segments the
    // buyer requests (M.12's segmentsPerUnit), not a flat per-upload price;
    // (3) the produced clip carries priority:"paid_boost" end to end
    // (submitGeneration -> generationJobs -> either straight into
    // priorityInbox if cached, or into danceQueue to be diverted there once
    // T34's ensureDanceSchedule reconciliation sees the job land) — it
    // never enters the vote-ranked path T27's mode-2 entries do.
    if (pathname === "/api/dance/upload-character" && req.method === "POST") {
      const user = requireUserSession(req);
      if (!user) {
        res.writeHead(401, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "login required" }));
        return;
      }
      if (!user.emailVerified) {
        res.writeHead(403, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "email verification required before uploading a character" }));
        return;
      }
      if (isBlacklisted("user", user.id)) {
        res.writeHead(403, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "account unavailable" }));
        return;
      }
      const boundary = boundaryFromContentType(req.headers["content-type"] || "");
      if (!boundary) {
        res.writeHead(400, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "expected multipart/form-data" }));
        return;
      }
      readRawBody(req)
        .then(async (raw) => {
          const parts = parseMultipart(raw, boundary);
          const filePart = parts.find((p) => p.name === "file");
          if (!filePart) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "missing file field" }));
            return;
          }
          const sniffed = sniffImageType(filePart.data);
          if (!sniffed) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "unrecognized image type (expected jpeg/png/webp)" }));
            return;
          }

          // 需求文档 3.3 第 4 点：衣服可选，指定就用指定的，否则系统随机
          // 挑一件衣柜库服装.
          const garmentIdPart = parts.find((p) => p.name === "garmentId");
          const requestedGarmentId = garmentIdPart ? garmentIdPart.data.toString("utf8").trim() : "";
          let targetGarment;
          if (requestedGarmentId) {
            targetGarment = garments.get(requestedGarmentId);
            if (!targetGarment || !targetGarment.isActive) {
              res.writeHead(400, { "Content-Type": "application/json" });
              res.end(JSON.stringify({ error: "garmentId must reference an active garment" }));
              return;
            }
          } else {
            const activeGarments = garments.list().filter((g) => g.isActive);
            if (!activeGarments.length) {
              res.writeHead(400, { "Content-Type": "application/json" });
              res.end(JSON.stringify({ error: "no active garments available to pair with the new character" }));
              return;
            }
            targetGarment = activeGarments[Math.floor(Math.random() * activeGarments.length)];
          }

          // 需求文档 3.3 第 3 点：花的积分决定能播放几个 10 秒片段.
          const segmentsPart = parts.find((p) => p.name === "segments");
          const requestedSegments = Math.min(20, Math.max(1, parseInt(segmentsPart ? segmentsPart.data.toString("utf8").trim() : "3", 10) || 3));
          const pricingEntry = pricing.get("spend_character_per_segment");
          if (!pricingEntry) {
            res.writeHead(500, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "spend_character_per_segment pricing not configured" }));
            return;
          }
          const cost = Math.ceil((pricingEntry.credits / (pricingEntry.segmentsPerUnit || 1)) * requestedSegments);

          let relPath, absPath;
          try {
            ({ relPath } = stripMetadataAndSave(filePart.data, sniffed));
            absPath = path.join(__dirname, relPath);
          } catch {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "failed to process image" }));
            return;
          }

          const moderation = await moderateFaceBlacklist(absPath, relPath);
          if (!moderation.approved) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "image rejected by moderation", reason: moderation.reason }));
            return;
          }

          const appearanceDescriptor = await describeCharacterImage(absPath);
          // 需求文档 3.3 第 6 点：新人物默认不沉淀进公共人物池（isDefault
          // 恒为 false，且不会被 /api/dance/pick 的默认人物逻辑抽中——那条
          // 逻辑只认 isDefault:true，一个 user_paid 人物永远不会是它）。
          const character = characters.create({
            name: `${user.nickname || user.email.split("@")[0]} 的新角色`,
            imageUrl: relPath,
            tags: [],
            source: "user_paid",
            ownerUserId: user.id,
            appearanceDescriptor,
            isDefault: false,
            moderationStatus: "auto_passed",
            totalSegments: requestedSegments,
            remainingSegments: requestedSegments,
            status: "active",
          });

          let spendRow;
          try {
            spendRow = creditLedger.spend({ userId: user.id, amount: cost, reason: "spend_character", relatedAssetId: character.id });
          } catch (err) {
            characters.remove(character.id);
            const status = err.code === "INSUFFICIENT_BALANCE" ? 402 : 500;
            res.writeHead(status, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: err.message }));
            return;
          }

          // priority:"paid_boost" (T34) — this is the one call site in the
          // whole codebase that requests it; mode 2 (T27) never does.
          const { status, body: respBody } = submitGeneration({
            characterId: character.id,
            garmentId: targetGarment.id,
            userId: user.id,
            priority: "paid_boost",
          });
          if (status !== 200) {
            creditLedger.refund({ userId: user.id, amount: cost, reason: "refund_stage2_fail", relatedAssetId: character.id });
            characters.remove(character.id);
            res.writeHead(status, { "Content-Type": "application/json" });
            res.end(JSON.stringify(respBody));
            return;
          }

          const entry = {
            id: crypto.randomUUID(),
            characterId: character.id,
            garmentId: targetGarment.id,
            nickname: user.nickname || null,
            userId: user.id,
            amountPaid: cost,
            priority: "paid_boost",
            submittedAt: Date.now(),
            votes: [],
          };
          // This character has never had a room before this call — its
          // first video (whether cached-instant or generated below) is what
          // creates one (getDanceRoomCharacterIds: "有视频就自动开间").
          const room = getDanceRoom(character.id);
          let videoId = null;
          if (respBody.cached) {
            // M.7 去重缓存命中是即时的 —— T34 的 ensureDanceSchedule 转运
            // 逻辑只在意"generating -> done"这个过渡，命中缓存跳过了整个
            // 过渡，所以这里直接进 priorityInbox，不经过 room.queue。
            videoId = respBody.clip.id;
            room.priorityInbox.push({ videoId, requestedBy: entry.nickname });
          } else {
            entry.status = "generating";
            entry.jobId = respBody.jobId;
            room.queue.push(entry);
          }
          saveDanceState();
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(
            JSON.stringify({
              status: respBody.cached ? "ready" : entry.status,
              id: entry.id,
              characterId: character.id,
              garmentId: targetGarment.id,
              videoId,
              creditsSpent: cost,
              totalSegments: requestedSegments,
              balanceAfter: spendRow.balanceAfter,
            })
          );
        })
        .catch((err) => {
          if (res.writableEnded) return;
          const status = err.code === "PAYLOAD_TOO_LARGE" ? 413 : 400;
          res.writeHead(status, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: err.message || "upload failed" }));
        });
      return;
    }

    if (pathname.startsWith("/api/dance/queue/vote/") && req.method === "POST") {
      const id = pathname.slice("/api/dance/queue/vote/".length);
      readJsonBody(req)
        .then((body) => {
          const uid = (body.uid || "").trim();
          if (!uid) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "uid required" }));
            return;
          }
          // id alone doesn't say which room's queue this is in — a vote can
          // land on any room, so search all of them.
          let entry;
          for (const room of Object.values(danceRooms)) {
            entry = room.queue.find((q) => q.id === id);
            if (entry) break;
          }
          if (!entry || !["generating", "ready", "failed"].includes(entry.status)) {
            res.writeHead(404, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "not found" }));
            return;
          }
          if (!Array.isArray(entry.votes)) entry.votes = [];
          const i = entry.votes.indexOf(uid);
          const voted = i === -1;
          if (voted) entry.votes.push(uid);
          else entry.votes.splice(i, 1);
          saveDanceState();
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ votes: entry.votes.length, voted }));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return;
    }

    if (pathname === "/api/library") {
      const sort = new URL(req.url, "http://x").searchParams.get("sort") || "newest";
      const lib = getLibrary().slice();
      const sorters = {
        newest: (a, b) => b.createdAt - a.createdAt,
        oldest: (a, b) => a.createdAt - b.createdAt,
        top: (a, b) => (b.likes || 0) - (a.likes || 0) || b.createdAt - a.createdAt,
      };
      lib.sort(sorters[sort] || sorters.newest);
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(JSON.stringify(lib));
      return;
    }

    if (pathname === "/api/live/state") {
      ensureSchedule();
      const now = Date.now();
      const params = new URL(req.url, "http://x").searchParams;
      const cid = params.get("cid");
      const uid = params.get("uid") || null;
      if (cid) viewers.set(cid, now);
      let idx = schedule.findIndex((s) => s.startAt <= now && now < s.endAt);
      if (idx === -1) idx = schedule.length - 1;
      const cur = schedule[idx];
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(
        JSON.stringify({
          now,
          watching: viewers.size,
          current: cur ? { clip: cur.clip, startAt: cur.startAt, endAt: cur.endAt, requestedBy: cur.requestedBy || null } : null,
          upNext: schedule.slice(idx + 1, idx + 4).map((s) => ({ ...s.clip, requestedBy: s.requestedBy || null })),
          queue: promptQueue
            .filter((q) => ["matched", "generating", "failed"].includes(q.status))
            .slice()
            .sort((a, b) => voteCount(b) - voteCount(a))
            .map((q) => ({
              id: q.id,
              prompt: q.prompt,
              nickname: q.nickname,
              status: q.status,
              error: q.error,
              votes: voteCount(q),
              voted: uid ? (q.votes || []).includes(uid) : false,
            })),
        })
      );
      return;
    }

    if (pathname === "/api/prompt" && req.method === "POST") {
      if (isRateLimited(req.socket.remoteAddress)) {
        res.writeHead(429, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: `最多每 ${RATE_LIMIT_WINDOW_MS / 60000} 分钟提交 ${RATE_LIMIT_MAX} 次，请稍后再试` }));
        return;
      }
      readJsonBody(req)
        .then((body) => {
          const prompt = (body.prompt || "").trim();
          if (!prompt || prompt.length > 300) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "prompt required, max 300 chars" }));
            return;
          }
          const result = submitPromptToQueue(Date.now().toString(36), prompt, null);
          saveLiveState();
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify(result));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return;
    }

    if (pathname === "/api/chat" && req.method === "GET") {
      const cid = new URL(req.url, "http://x").searchParams.get("cid");
      if (cid) viewers.set(cid, Date.now());
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(JSON.stringify(chatMessages.slice(-100)));
      return;
    }

    if (pathname === "/api/chat" && req.method === "POST") {
      if (isRateLimited(req.socket.remoteAddress)) {
        res.writeHead(429, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: `最多每 ${RATE_LIMIT_WINDOW_MS / 60000} 分钟发送 ${RATE_LIMIT_MAX} 条，请稍后再试` }));
        return;
      }
      readJsonBody(req)
        .then((body) => {
          const uid = (body.uid || "").trim();
          const nickname = (body.nickname || "").trim().slice(0, 20);
          const text = (body.text || "").trim();
          if (!uid || !nickname || !text || text.length > 300) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "uid, nickname, text required, text max 300 chars" }));
            return;
          }
          const id = `${Date.now().toString(36)}${Math.random().toString(36).slice(2, 6)}`;
          const msg = { id, uid, nickname, text, createdAt: Date.now() };

          const mod = moderateText(text);
          if (!mod.ok) {
            msg.status = "rejected";
            msg.rejectReason = mod.reason;
            pushChatMessage(msg);
            saveLiveState();
            res.writeHead(200, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ status: "rejected", reason: mod.reason }));
            return;
          }

          msg.status = "approved";
          pushChatMessage(msg);
          const result = submitPromptToQueue(id, text, nickname);
          msg.status = result.status; // "matched" | "generating"
          saveLiveState();
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify(result));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return;
    }

    if (pathname === "/api/admin/library" && req.method === "POST") {
      readJsonBody(req)
        .then((body) => {
          const prompt = (body.prompt || "").trim();
          const videoUrl = (body.videoUrl || "").trim();
          if (!prompt || !videoUrl) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "prompt and videoUrl required" }));
            return;
          }
          const clip = {
            id: `manual-${Date.now().toString(36)}${Math.random().toString(36).slice(2, 6)}`,
            source: "manual",
            edited: true,
            prompt,
            promptEn: (body.promptEn || "").trim(),
            fullPrompt: (body.fullPrompt || prompt).trim(),
            videoUrl,
            width: body.width || null,
            height: body.height || null,
            duration: body.duration || null,
            partition: "manual",
            likes: 0,
            createdAt: Date.now(),
            // channel: "dance" puts this clip in dance.html's pool
            // (pickNextClip filters on it, architecture.md 2.1); anything
            // else stays out of it and is live.html's/text-channel pool.
            channel: body.channel === "dance" ? "dance" : undefined,
          };
          const lib = getLibrary();
          lib.push(clip);
          saveLibrary(lib);
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify(clip));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return;
    }

    if (pathname.startsWith("/api/admin/library/") && req.method === "PATCH") {
      const id = pathname.slice("/api/admin/library/".length);
      readJsonBody(req)
        .then((body) => {
          const lib = getLibrary();
          const clip = lib.find((c) => c.id === id);
          if (!clip) {
            res.writeHead(404, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "not found" }));
            return;
          }
          for (const field of ["prompt", "promptEn", "fullPrompt", "videoUrl"]) {
            if (typeof body[field] === "string" && body[field].trim()) clip[field] = body[field].trim();
          }
          // qcStatus/qcNote (2026-09 video QC): admin manually overriding an
          // AI verdict or setting one by hand — qcNote allowed to be blanked
          // out (e.g. clearing a note when flipping back to "correct"), so
          // it's handled separately from the trim-if-nonblank fields above.
          if (body.qcStatus === "pending" || body.qcStatus === "correct" || body.qcStatus === "incorrect") {
            clip.qcStatus = body.qcStatus;
            clip.published = body.qcStatus === "correct"; // 通过验证的自动上架
          }
          if (typeof body.qcNote === "string") clip.qcNote = body.qcNote.trim();
          if (body.channel === "dance" || body.channel === "video") clip.channel = body.channel === "dance" ? "dance" : undefined;
          // 上架/下架 (2026-09): explicit manual override, applied after the
          // auto-publish-on-QC above so an admin toggle in the same request
          // (or a later one) always wins over the automatic default.
          if (body.published === true || body.published === "true") clip.published = true;
          else if (body.published === false || body.published === "false") clip.published = false;
          // Storing a videoUrl (whether this clip started as h3console or
          // manual) means /lib/video/:id should serve that directly instead
          // of proxying the H3 console — see the handler below.
          if (body.videoUrl) clip.source = "manual";
          // Marks this entry as admin-owned so the periodic H3 library sync
          // (ingest.js's syncLibrary) carries it forward as-is instead of
          // overwriting it with a freshly re-extracted prompt.
          clip.edited = true;
          saveLibrary(lib);
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify(clip));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return;
    }

    if (pathname.startsWith("/api/admin/library/") && req.method === "DELETE") {
      const id = pathname.slice("/api/admin/library/".length);
      const lib = getLibrary();
      const clip = lib.find((c) => c.id === id);
      if (!clip) {
        res.writeHead(404, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "not found" }));
        return;
      }
      saveLibrary(lib.filter((c) => c.id !== id));
      // Without this, the next periodic syncLibrary() would just re-add it —
      // it's still a "done" job on the H3 console until explicitly deleted there too.
      const cleanup = clip.source === "h3console" ? h3ConsoleFetch(`/v1/videos/${id}`, { method: "DELETE" }).catch(() => {}) : Promise.resolve();
      cleanup.then(() => {
        res.writeHead(200, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ deleted: true }));
      });
      return;
    }

    // Single-clip AI QC check (admin-dance-library.html's per-row "AI检查"
    // button) — synchronous, returns the updated clip once GLM responds.
    if (pathname.startsWith("/api/admin/library/") && pathname.endsWith("/qc-check") && req.method === "POST") {
      const id = pathname.slice("/api/admin/library/".length, -"/qc-check".length);
      const lib = getLibrary();
      const clip = lib.find((c) => c.id === id && c.channel === "dance");
      if (!clip) {
        res.writeHead(404, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "not found" }));
        return;
      }
      runDanceClipQc(clip)
        .then(({ qcStatus, qcNote }) => {
          clip.qcStatus = qcStatus;
          clip.qcNote = qcNote;
          clip.published = qcStatus === "correct"; // 通过验证的自动上架
          saveLibrary(lib);
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify(clip));
        })
        .catch((err) => {
          res.writeHead(502, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: err.message }));
        });
      return;
    }

    // Batch AI QC (admin-dance-qc.html): {clipIds?[]} — omit clipIds to
    // check every channel:"dance" clip whose qcStatus is still "pending".
    // Fire-and-forget: returns a batchId immediately, runQcBatch works
    // through it sequentially in the background (see its own comment on
    // why sequential, not concurrent).
    if (pathname === "/api/admin/dance-qc/batch" && req.method === "POST") {
      readJsonBody(req)
        .then((body) => {
          const dance = getLibrary().filter((c) => c.channel === "dance");
          const clipIds = Array.isArray(body.clipIds) && body.clipIds.length ? body.clipIds : dance.filter((c) => (c.qcStatus || "pending") === "pending").map((c) => c.id);
          const batchId = crypto.randomUUID();
          qcBatchJobs.set(batchId, { total: clipIds.length, checked: 0, results: [], status: "running", cancelled: false });
          runQcBatch(batchId, clipIds).catch(() => {});
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ batchId, total: clipIds.length }));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return;
    }

    if (pathname.startsWith("/api/admin/dance-qc/batch/") && req.method === "GET") {
      const batchId = pathname.slice("/api/admin/dance-qc/batch/".length);
      const job = qcBatchJobs.get(batchId);
      if (!job) {
        res.writeHead(404, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "not found" }));
        return;
      }
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(JSON.stringify(job));
      return;
    }

    if (pathname.startsWith("/api/admin/dance-qc/batch/") && pathname.endsWith("/cancel") && req.method === "POST") {
      const batchId = pathname.slice("/api/admin/dance-qc/batch/".length, -"/cancel".length);
      const job = qcBatchJobs.get(batchId);
      if (job) job.cancelled = true;
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(JSON.stringify({ ok: true }));
      return;
    }

    if (pathname.startsWith("/api/queue/vote/") && req.method === "POST") {
      const id = pathname.slice("/api/queue/vote/".length);
      readJsonBody(req)
        .then((body) => {
          const uid = (body.uid || "").trim();
          if (!uid) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "uid required" }));
            return;
          }
          const entry = promptQueue.find((q) => q.id === id);
          if (!entry || !["matched", "generating", "ready"].includes(entry.status)) {
            res.writeHead(404, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "not found" }));
            return;
          }
          if (!Array.isArray(entry.votes)) entry.votes = [];
          const i = entry.votes.indexOf(uid);
          const voted = i === -1;
          if (voted) entry.votes.push(uid);
          else entry.votes.splice(i, 1);
          saveLiveState();
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ votes: entry.votes.length, voted }));
        })
        .catch(() => {
          res.writeHead(400, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ error: "invalid JSON body" }));
        });
      return;
    }

    if (pathname.startsWith("/api/like/") && req.method === "POST") {
      const id = pathname.slice("/api/like/".length);
      const lib = getLibrary();
      const clip = lib.find((c) => c.id === id);
      if (!clip) {
        res.writeHead(404, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "not found" }));
        return;
      }
      clip.likes = (clip.likes || 0) + 1;
      saveLibrary(lib);
      res.writeHead(200, { "Content-Type": "application/json" });
      res.end(JSON.stringify({ likes: clip.likes }));
      return;
    }

    if (pathname === "/api/admin/upload" && req.method === "POST") {
      const boundary = boundaryFromContentType(req.headers["content-type"] || "");
      if (!boundary) {
        res.writeHead(400, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "expected multipart/form-data" }));
        return;
      }
      readRawBody(req)
        .then((body) => {
          const filePart = parseMultipart(body, boundary).find((p) => p.name === "file");
          if (!filePart) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "missing file field" }));
            return;
          }
          const sniffed = sniffImageType(filePart.data);
          if (!sniffed) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "unrecognized image type (expected jpeg/png/webp)" }));
            return;
          }
          try {
            const { relPath } = stripMetadataAndSave(filePart.data, sniffed);
            res.writeHead(200, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ url: relPath }));
          } catch {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "failed to process image" }));
          }
        })
        .catch((err) => {
          if (res.writableEnded) return;
          try {
            const status = err.code === "PAYLOAD_TOO_LARGE" ? 413 : 400;
            res.writeHead(status, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: err.message }));
          } catch {
            // socket already gone (e.g. destroyed for exceeding the size cap)
          }
        });
      return;
    }

    if (pathname === "/api/admin/upload-video" && req.method === "POST") {
      const boundary = boundaryFromContentType(req.headers["content-type"] || "");
      if (!boundary) {
        res.writeHead(400, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "expected multipart/form-data" }));
        return;
      }
      readRawBody(req, 50 * 1024 * 1024)
        .then((body) => {
          const filePart = parseMultipart(body, boundary).find((p) => p.name === "file");
          if (!filePart) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "missing file field" }));
            return;
          }
          const sniffed = sniffVideoType(filePart.data);
          if (!sniffed) {
            res.writeHead(400, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: "unrecognized video type (expected mp4)" }));
            return;
          }
          const { relPath } = saveVideoUpload(filePart.data, sniffed);
          res.writeHead(200, { "Content-Type": "application/json" });
          res.end(JSON.stringify({ url: relPath }));
        })
        .catch((err) => {
          if (res.writableEnded) return;
          try {
            const status = err.code === "PAYLOAD_TOO_LARGE" ? 413 : 400;
            res.writeHead(status, { "Content-Type": "application/json" });
            res.end(JSON.stringify({ error: err.message }));
          } catch {
            // socket already gone (e.g. destroyed for exceeding the size cap)
          }
        });
      return;
    }

    if (pathname.startsWith("/uploads/")) {
      const rel = pathname.slice("/uploads/".length);
      const abs = path.join(UPLOADS_DIR, rel);
      if (!abs.startsWith(UPLOADS_DIR + path.sep)) {
        res.writeHead(403);
        res.end("Forbidden");
        return;
      }
      // Range support is required here, not optional: <video> elements probe
      // duration/seekability with a Range request, and without a 206 reply
      // (plus Content-Length) Chrome's media pipeline can get stuck at
      // readyState 0 forever — the video never becomes playable.
      fs.stat(abs, (err, stat) => {
        if (err || !stat.isFile()) {
          res.writeHead(404);
          res.end("Not found");
          return;
        }
        const contentType = MIME[path.extname(abs)] || "application/octet-stream";
        const range = req.headers.range;
        const match = range && /^bytes=(\d*)-(\d*)$/.exec(range);
        if (match) {
          const start = match[1] ? parseInt(match[1], 10) : 0;
          const end = match[2] ? parseInt(match[2], 10) : stat.size - 1;
          if (start > end || end >= stat.size) {
            res.writeHead(416, { "Content-Range": `bytes */${stat.size}` });
            res.end();
            return;
          }
          res.writeHead(206, {
            "Content-Type": contentType,
            "Content-Length": end - start + 1,
            "Content-Range": `bytes ${start}-${end}/${stat.size}`,
            "Accept-Ranges": "bytes",
          });
          fs.createReadStream(abs, { start, end }).pipe(res);
          return;
        }
        res.writeHead(200, { "Content-Type": contentType, "Content-Length": stat.size, "Accept-Ranges": "bytes" });
        fs.createReadStream(abs).pipe(res);
      });
      return;
    }

    if (pathname.startsWith("/lib/video/")) {
      const id = pathname.slice("/lib/video/".length);
      const clip = getLibrary().find((c) => c.id === id);
      if (clip && clip.videoUrl) {
        res.writeHead(302, { Location: clip.videoUrl });
        res.end();
        return;
      }
      if (!H3_CONSOLE_URL) {
        res.writeHead(500, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: "H3_CONSOLE_BASE not configured" }));
        return;
      }
      const upstreamHeaders = { Authorization: `Bearer ${H3_CONSOLE_TOKEN}` };
      if (req.headers.range) upstreamHeaders.range = req.headers.range;
      const proxyReq = http.request(
        {
          hostname: H3_CONSOLE_URL.hostname,
          port: H3_CONSOLE_URL.port || 80,
          path: `${H3_CONSOLE_URL.pathname}/v1/videos/${id}/file`,
          method: "GET",
          headers: upstreamHeaders,
        },
        (proxyRes) => {
          res.writeHead(proxyRes.statusCode, proxyRes.headers);
          proxyRes.pipe(res);
        }
      );
      proxyReq.on("error", (err) => {
        res.writeHead(502, { "Content-Type": "application/json" });
        res.end(JSON.stringify({ error: { message: err.message } }));
      });
      proxyReq.end();
      return;
    }
    const filePath = path.join(__dirname, pathname === "/" ? "/index.html" : pathname);
    fs.readFile(filePath, (err, data) => {
      if (err) {
        res.writeHead(404);
        res.end("Not found");
        return;
      }
      res.writeHead(200, { "Content-Type": MIME[path.extname(filePath)] || "application/octet-stream" });
      res.end(data);
    });
  })
  .listen(PORT, () => console.log(`http://localhost:${PORT}`));

resumeGenerations();
resumeDressupGenerations();
resumeDressgenTasks();

// Auto-sync the library from the H3 Console so content added there directly
// (not through our own /api/prompt) shows up without a manual `node ingest.js`.
const LIBRARY_SYNC_INTERVAL_MS = 5 * 60 * 1000;
syncLibrary()
  .then((n) => console.log(`library synced — ${n} clips`))
  .catch((err) => console.error(`library sync failed: ${err.message}`));
setInterval(() => {
  syncLibrary().catch((err) => console.error(`library sync failed: ${err.message}`));
}, LIBRARY_SYNC_INTERVAL_MS);