// 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 crypto = require("crypto");

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";

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,
} = require("./uploads.js");
const { characters, garments, danceRefs } = require("./dressup-store.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));
}

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));
}

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);
  });
}

// 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;
}

function isAdminAuthed(req) {
  const token = parseCookies(req)[ADMIN_SESSION_COOKIE];
  if (!token) return false;
  const expiresAt = adminSessions.get(token);
  if (!expiresAt || expiresAt < Date.now()) {
    adminSessions.delete(token);
    return false;
  }
  return true;
}

// 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 } = 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 removed = store.remove(id);
      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: unsetOtherDefaultCharacters,
  onUpdate: unsetOtherDefaultCharacters,
});

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),
        },
});

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();
  });
}

function glmChat(messages) {
  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(15000, () => req.destroy(new Error("GLM request timed out")));
    req.write(body);
    req.end();
  });
}

// 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;
  }
}

// ---- 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;

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}]

// ---- 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);
}

// 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;
}
function pickBestIndexByStatus(status) {
  let bestIdx = -1;
  for (let i = 0; i < promptQueue.length; i++) {
    const q = promptQueue[i];
    if (q.status !== status) continue;
    if (bestIdx === -1) {
      bestIdx = i;
      continue;
    }
    const best = promptQueue[bestIdx];
    if (voteCount(q) > voteCount(best)) bestIdx = i;
  }
  return bestIdx;
}
function pickNextClip() {
  const readyIdx = pickBestIndexByStatus("ready");
  if (readyIdx !== -1) {
    const q = promptQueue.splice(readyIdx, 1)[0];
    return { clip: q.clip, requestedBy: q.nickname, chatId: q.id };
  }
  const matchedIdx = pickBestIndexByStatus("matched");
  if (matchedIdx !== -1) {
    const q = promptQueue.splice(matchedIdx, 1)[0];
    return { clip: q.clip, requestedBy: q.nickname, chatId: q.id };
  }

  const lib = getLibrary();
  if (!lib.length) return null;
  const prev = schedule.length ? schedule[schedule.length - 1].clip.id : null;
  const notPrev = lib.length > 1 ? lib.filter((c) => c.id !== prev) : lib;
  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 pool = offCooldown.length ? offCooldown : notPrev;
  // Within that pool, only randomize among the least-played clips — keeps
  // rotation even instead of letting a few clips dominate airtime by chance.
  const minPlays = Math.min(...pool.map((c) => c.playCount || 0));
  const leastPlayed = pool.filter((c) => (c.playCount || 0) === minPlays);
  return { clip: leastPlayed[Math.floor(Math.random() * leastPlayed.length)], requestedBy: null, chatId: 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, 2000);

// ---- 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

// ---- 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();
    }
  }
}

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;
    }

    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 (garmentsCrud(pathname, req, res)) return;
    if (danceRefsCrud(pathname, req, res)) 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(),
          };
          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();
          }
          // 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;
    }

    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;
      }
      fs.readFile(abs, (err, data) => {
        if (err) {
          res.writeHead(404);
          res.end("Not found");
          return;
        }
        res.writeHead(200, { "Content-Type": MIME[path.extname(abs)] || "application/octet-stream" });
        res.end(data);
      });
      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();

// 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);