/**
 * DevLoop · doc-tools (PM + Architect 用，11 个工具)
 *
 *  bootstrap_prd_site         init prd/ 站点 (copy shell.css/js + 建目录)
 *  bootstrap_sdd_site         同上,SDD
 *  write_chapter              写 PRD chapter (走 docStore.writePrdChapter)
 *  write_mvcp_page            写 SDD MVCP 页(model/view/control/process 之一)
 *  archive_doc                把当前 prd|sdd|units 归档到 history/
 *  diff_html                  cheerio section 级 diff (返 added/changed/removed 列表)
 *  diff_units                 units.json 三态 diff
 *  echo_diff                  发 SSE prd.updated/sdd.updated + change_summary
 *  update_search_index        重建 prd|sdd 站点的 search-index.json (复用 build-search-index 脚本)
 *  validate_prd_site          整站 cheerio 校验 + 8 类信息 ≥4
 *  validate_sdd_consistency   SDD ↔ units.json ↔ integration/spec.json 一致性
 *  hash_contract              暴露 docStore.hashContract
 *
 * 规格: docs/prd/newfunction/_spec/sdd-control.md
 *      docs/prd/newfunction/_spec/agents-pm.md
 *      docs/prd/newfunction/_spec/agents-architect.md
 */

const fs = require('fs');
const path = require('path');
const { spawn } = require('child_process');
const cheerio = require('cheerio');

const pathResolver = require('../../../services/devloop/path-resolver');
const docStore = require('../../../services/devloop/doc-store');
const unitRegistry = require('../../../services/devloop/unit-registry');
const changelogWriter = require('../../../services/devloop/changelog-writer');
const { ToolValidationError } = require('./_errors');

// 模板目录：copy shell.css/shell.js 进项目站点
const TEMPLATE_ASSETS_DIR = path.resolve(__dirname, '../../../../docs/prd/newfunction/assets');

// ────────────────────────────────────────────────────────────────
// bootstrap_prd_site / bootstrap_sdd_site
// ────────────────────────────────────────────────────────────────

function _bootstrapSite(siteRoot, kind) {
  const subdirs = kind === 'prd'
    ? ['product', 'feature', 'flow', 'prototype', 'assets']
    : ['mvcp', 'assets'];

  for (const d of subdirs) fs.mkdirSync(path.join(siteRoot, d), { recursive: true });

  // 复制 shell.css + shell.js (如模板存在)
  for (const f of ['shell.css', 'shell.js']) {
    const src = path.join(TEMPLATE_ASSETS_DIR, f);
    const dst = path.join(siteRoot, 'assets', f);
    if (fs.existsSync(src) && !fs.existsSync(dst)) {
      fs.copyFileSync(src, dst);
    } else if (!fs.existsSync(dst)) {
      // 模板不存在时落空文件 (开发 / 测试场景)
      fs.writeFileSync(dst, `/* ${f} placeholder; copy real template here */\n`);
    }
  }
  // 空的 search-index.json
  const idx = path.join(siteRoot, 'assets', 'search-index.json');
  if (!fs.existsSync(idx)) {
    fs.writeFileSync(idx, JSON.stringify({ version: '1', pages: 0, entries: [] }));
  }
  return { ok: true, root: siteRoot, dirs: subdirs.length, assets: 3 };
}

const bootstrap_prd_site = {
  name: 'bootstrap_prd_site',
  description: '初始化项目 prd/ 站点目录(含 assets/shell.css + shell.js + search-index.json 占位)。',
  inputSchema: { type: 'object', properties: {} },
  async execute(_input, ctx) {
    _req(ctx, ['pid']);
    return _bootstrapSite(pathResolver.resolvePrdSite(ctx.pid), 'prd');
  },
};

const bootstrap_sdd_site = {
  name: 'bootstrap_sdd_site',
  description: '初始化项目 sdd/ 站点目录(含 mvcp/ + assets/)。',
  inputSchema: { type: 'object', properties: {} },
  async execute(_input, ctx) {
    _req(ctx, ['pid']);
    return _bootstrapSite(pathResolver.resolveSddSite(ctx.pid), 'sdd');
  },
};

// ────────────────────────────────────────────────────────────────
// write_chapter / write_mvcp_page
// ────────────────────────────────────────────────────────────────

const write_chapter = {
  name: 'write_chapter',
  description: '写 PRD chapter (HTML)。kind=prd 时走 prd/{relPath};kind=sdd 时走 sdd/{relPath}。自动校验 + 归档旧版。',
  inputSchema: {
    type: 'object',
    required: ['kind', 'relPath', 'html'],
    properties: {
      kind: { type: 'string', enum: ['prd', 'sdd'] },
      relPath: { type: 'string', minLength: 1 },
      html: { type: 'string', minLength: 1 },
    },
  },
  async execute({ kind, relPath, html }, ctx) {
    _req(ctx, ['pid']);
    const writeFn = kind === 'prd' ? docStore.writePrdChapter : docStore.writeSddChapter;
    try {
      const r = writeFn(ctx.pid, relPath, html);
      return { ok: true, ...r };
    } catch (e) {
      if (e.name === 'ValidationError') {
        throw new ToolValidationError('html', `${e.message}: ${e.details?.join(' · ')}`);
      }
      throw e;
    }
  },
};

const write_mvcp_page = {
  name: 'write_mvcp_page',
  description: '写 SDD MVCP 页 (mvcp/{model|view|control|process}.html)。等价于 write_chapter(kind=sdd, relPath=mvcp/{which}.html)。',
  inputSchema: {
    type: 'object',
    required: ['which', 'html'],
    properties: {
      which: { type: 'string', enum: ['model', 'view', 'control', 'process'] },
      html: { type: 'string', minLength: 1 },
    },
  },
  async execute({ which, html }, ctx) {
    return write_chapter.execute(
      { kind: 'sdd', relPath: `mvcp/${which}.html`, html },
      ctx
    );
  },
};

// ────────────────────────────────────────────────────────────────
// archive_doc
// ────────────────────────────────────────────────────────────────

const archive_doc = {
  name: 'archive_doc',
  description: '手动触发归档当前 prd/ 或 sdd/ 整站到 history/ (write_chapter 已自动归档单文件; 此工具用于整站快照)。',
  inputSchema: {
    type: 'object',
    required: ['kind'],
    properties: {
      kind: { type: 'string', enum: ['prd', 'sdd'] },
    },
  },
  async execute({ kind }, ctx) {
    _req(ctx, ['pid']);
    const siteRoot = kind === 'prd'
      ? pathResolver.resolvePrdSite(ctx.pid)
      : pathResolver.resolveSddSite(ctx.pid);
    if (!fs.existsSync(siteRoot)) {
      throw new ToolValidationError('kind', `${kind}/ does not exist`);
    }

    // 找 rev (扫所有 chapter article data-rev 取最大)
    const rev = _detectSiteRev(siteRoot, kind);

    const historyDir = path.join(
      pathResolver.resolveHistoryDir(ctx.pid),
      `${kind}-rev-${rev}`
    );
    _copyDir(siteRoot, historyDir);
    return { ok: true, rev, archived_to: historyDir };
  },
};

function _detectSiteRev(siteRoot, kind) {
  let maxRev = 0;
  function walk(dir) {
    for (const e of fs.readdirSync(dir, { withFileTypes: true })) {
      const full = path.join(dir, e.name);
      if (e.isDirectory()) {
        if (e.name !== 'assets') walk(full);
      } else if (e.name.endsWith('.html')) {
        try {
          const $ = cheerio.load(fs.readFileSync(full, 'utf8'));
          const r = $(`article[data-doc="${kind}"]`).first().attr('data-rev');
          if (r && /^\d+$/.test(r)) {
            const n = parseInt(r, 10);
            if (n > maxRev) maxRev = n;
          }
        } catch { /* ignore */ }
      }
    }
  }
  walk(siteRoot);
  return maxRev || 1;
}

function _copyDir(src, dst) {
  fs.mkdirSync(dst, { recursive: true });
  for (const e of fs.readdirSync(src, { withFileTypes: true })) {
    const s = path.join(src, e.name);
    const d = path.join(dst, e.name);
    if (e.isDirectory()) _copyDir(s, d);
    else fs.copyFileSync(s, d);
  }
}

// ────────────────────────────────────────────────────────────────
// diff_html
// ────────────────────────────────────────────────────────────────

const diff_html = {
  name: 'diff_html',
  description: 'cheerio section 级 diff:对比 oldHtml 和 newHtml,返 added/changed/removed section data-rev 列表。',
  inputSchema: {
    type: 'object',
    required: ['oldHtml', 'newHtml'],
    properties: {
      oldHtml: { type: 'string' },
      newHtml: { type: 'string' },
    },
  },
  async execute({ oldHtml, newHtml }, _ctx) {
    const $o = cheerio.load(oldHtml || '');
    const $n = cheerio.load(newHtml || '');
    const oldSecs = new Map();
    const newSecs = new Map();
    $o('section[data-rev]').each((_, el) => {
      const r = $o(el).attr('data-rev');
      oldSecs.set(r, $o(el).text().trim());
    });
    $n('section[data-rev]').each((_, el) => {
      const r = $n(el).attr('data-rev');
      newSecs.set(r, $n(el).text().trim());
    });
    const added = [], changed = [], removed = [];
    for (const [r, txt] of newSecs) {
      if (!oldSecs.has(r)) added.push(r);
      else if (oldSecs.get(r) !== txt) changed.push(r);
    }
    for (const [r] of oldSecs) {
      if (!newSecs.has(r)) removed.push(r);
    }
    return { added, changed, removed };
  },
};

// ────────────────────────────────────────────────────────────────
// diff_units
// ────────────────────────────────────────────────────────────────

const diff_units = {
  name: 'diff_units',
  description: '对比新旧 units.json: added/changed(contract_hash 变化)/removed。如不传 oldUnits,从 history/最新 units-rev-N.json 读。',
  inputSchema: {
    type: 'object',
    required: ['newUnits'],
    properties: {
      newUnits: { type: 'array' },
      oldUnits: { type: 'array' },
    },
  },
  async execute({ newUnits, oldUnits }, ctx) {
    let oldList = oldUnits;
    if (!oldList && ctx?.pid) {
      // 尝试从 history/ 取最新归档
      const historyDir = pathResolver.resolveHistoryDir(ctx.pid);
      if (fs.existsSync(historyDir)) {
        const files = fs.readdirSync(historyDir).filter(f => /^units-rev-\d+\.json$/.test(f));
        if (files.length) {
          files.sort();
          const last = files[files.length - 1];
          const old = JSON.parse(fs.readFileSync(path.join(historyDir, last), 'utf8'));
          oldList = old.units || [];
        }
      }
    }
    return unitRegistry.diffUnits(oldList || [], newUnits);
  },
};

// ────────────────────────────────────────────────────────────────
// echo_diff
// ────────────────────────────────────────────────────────────────

const echo_diff = {
  name: 'echo_diff',
  description: '发 SSE 事件 prd.updated 或 sdd.updated,告知 Dashboard 文档已变。',
  inputSchema: {
    type: 'object',
    required: ['kind', 'rev', 'summary'],
    properties: {
      kind: { type: 'string', enum: ['prd', 'sdd'] },
      rev: { type: 'integer' },
      summary: { type: 'string', maxLength: 500 },
      sections_diff: { type: 'object' },
    },
  },
  async execute({ kind, rev, summary, sections_diff }, ctx) {
    _req(ctx, ['pid']);
    if (ctx.sseBroker) {
      ctx.sseBroker.emit(ctx.pid, `${kind}.updated`, {
        rev, summary, sections_diff: sections_diff || null,
      });
    }
    // 同步写 changelog
    try {
      changelogWriter.append(ctx.pid, {
        kind: `${kind}_rev`,
        rev,
        by: ctx.agent || 'system',
        trigger: 'agent',
        summary,
        diff: sections_diff || {},
      });
    } catch (e) {
      // 已存在该 rev → 跳过；其他错误抛
      if (!/already/.test(e.message)) { /* swallow */ }
    }
    return { ok: true };
  },
};

// ────────────────────────────────────────────────────────────────
// update_search_index
// ────────────────────────────────────────────────────────────────

const update_search_index = {
  name: 'update_search_index',
  description: '重建 prd/ 或 sdd/ 站点的 search-index.json (复用 scripts/build-search-index.js 的逻辑)。',
  inputSchema: {
    type: 'object',
    properties: {
      target: { type: 'string', enum: ['prd', 'sdd', 'both'], default: 'both' },
    },
  },
  async execute({ target = 'both' }, ctx) {
    _req(ctx, ['pid']);
    const built = [];
    if (target === 'prd' || target === 'both') {
      built.push(_buildSiteIndex(pathResolver.resolvePrdSite(ctx.pid)));
    }
    if (target === 'sdd' || target === 'both') {
      built.push(_buildSiteIndex(pathResolver.resolveSddSite(ctx.pid)));
    }
    return { ok: true, built };
  },
};

function _buildSiteIndex(siteRoot) {
  if (!fs.existsSync(siteRoot)) return { skipped: true, reason: 'site not exist' };
  const entries = [];
  function walk(dir, prefix) {
    for (const e of fs.readdirSync(dir, { withFileTypes: true })) {
      if (e.name === 'assets') continue;
      const rel = prefix ? `${prefix}/${e.name}` : e.name;
      const full = path.join(dir, e.name);
      if (e.isDirectory()) walk(full, rel);
      else if (e.name.endsWith('.html')) {
        const html = fs.readFileSync(full, 'utf8');
        const title = _extractTitle(html) || rel;
        const text = _stripTagsKeepText(html).slice(0, 2000);
        entries.push({ f: rel, title, content: text });
      }
    }
  }
  walk(siteRoot, '');

  const idx = {
    version: '1', generated: new Date().toISOString(),
    pages: entries.length, entries,
  };
  const out = path.join(siteRoot, 'assets', 'search-index.json');
  fs.mkdirSync(path.dirname(out), { recursive: true });
  fs.writeFileSync(out, JSON.stringify(idx));
  return { ok: true, pages: entries.length, path: out };
}

function _extractTitle(html) {
  const m = html.match(/<title>([\s\S]*?)<\/title>/i);
  return m ? m[1].trim() : null;
}

function _stripTagsKeepText(s) {
  return s
    .replace(/<script[\s\S]*?<\/script>/gi, ' ')
    .replace(/<style[\s\S]*?<\/style>/gi, ' ')
    .replace(/<svg[\s\S]*?<\/svg>/gi, ' ')
    .replace(/<[^>]+>/g, ' ')
    .replace(/\s+/g, ' ')
    .trim();
}

// ────────────────────────────────────────────────────────────────
// validate_prd_site
// ────────────────────────────────────────────────────────────────

const REQUIRED_PRD_CHAPTERS = [
  'index.html',
  'product/background.html',
  'product/personas.html',
  'product/scope.html',
  'feature/feature-tree.html',
  'flow/user-flows.html',
];

const EIGHT_TYPES = {
  Tables:        $ => $('table').length > 0,
  Code:          $ => $('pre').length > 0,
  Illustrations: $ => $('svg').length > 0,
  Interaction:   $ => $('.tabs, details, nav').length > 0,
  Spatial:       $ => $('pre').filter((_,el) => $(el).text().includes('├──') || $(el).text().includes('└──')).length > 0,
  Design:        $ => $('.card').length > 0 || $('[class*=card]').length > 0,
  Images:        $ => $('svg, img').length > 0,
  Workflows:     $ => $('svg').filter((_,el) => /marker-end|stroke-dasharray|arrow/.test($(el).html() || '')).length > 0,
};

const validate_prd_site = {
  name: 'validate_prd_site',
  description: '整站校验 PRD: 必备章节存在 · cheerio 结构 · 8 类信息 ≥4。',
  inputSchema: { type: 'object', properties: {} },
  async execute(_input, ctx) {
    _req(ctx, ['pid']);
    const root = pathResolver.resolvePrdSite(ctx.pid);
    const issues = [];
    if (!fs.existsSync(root)) {
      return { ok: false, issues: ['prd/ site not initialized'] };
    }

    for (const f of REQUIRED_PRD_CHAPTERS) {
      const p = path.join(root, f);
      if (!fs.existsSync(p)) issues.push(`missing chapter: ${f}`);
    }

    // 扫所有 chapter
    const allFiles = [];
    function walk(dir, prefix) {
      for (const e of fs.readdirSync(dir, { withFileTypes: true })) {
        if (e.name === 'assets') continue;
        const rel = prefix ? `${prefix}/${e.name}` : e.name;
        const full = path.join(dir, e.name);
        if (e.isDirectory()) walk(full, rel);
        else if (e.name.endsWith('.html')) allFiles.push({ rel, full });
      }
    }
    walk(root, '');

    for (const { rel, full } of allFiles) {
      const html = fs.readFileSync(full, 'utf8');
      const v = docStore.validateHTML(html, 'prd');
      if (!v.ok) {
        for (const e of v.errors) issues.push(`${rel}: ${e}`);
      }
      // 8 类信息检查
      try {
        const $ = cheerio.load(html);
        const covered = Object.entries(EIGHT_TYPES).filter(([_, fn]) => fn($));
        if (covered.length < 4) {
          issues.push(`${rel}: only ${covered.length}/8 info types (need ≥4)`);
        }
      } catch { /* ignore */ }
    }

    return { ok: issues.length === 0, issues };
  },
};

// ────────────────────────────────────────────────────────────────
// validate_sdd_consistency
// ────────────────────────────────────────────────────────────────

const validate_sdd_consistency = {
  name: 'validate_sdd_consistency',
  description: 'SDD ↔ units.json ↔ integration/spec.json 三方一致性: 每 Unit 在 sdd/mvcp/ 出现 · involves ⊆ units · contract_hash 一致 · DAG 无环。',
  inputSchema: { type: 'object', properties: {} },
  async execute(_input, ctx) {
    _req(ctx, ['pid']);
    const issues = [];

    const unitsJson = docStore.readUnits(ctx.pid);
    if (!unitsJson) return { ok: false, issues: ['units.json missing'] };

    const v = docStore.validateUnitsSchema(unitsJson);
    if (!v.ok) issues.push(...v.errors);

    // Unit 在 sdd/mvcp/ 至少出现 1 次
    const sddRoot = pathResolver.resolveSddSite(ctx.pid);
    const mvcpDir = path.join(sddRoot, 'mvcp');
    let sddText = '';
    if (fs.existsSync(mvcpDir)) {
      for (const f of fs.readdirSync(mvcpDir)) {
        if (f.endsWith('.html')) sddText += fs.readFileSync(path.join(mvcpDir, f), 'utf8');
      }
    }
    for (const u of unitsJson.units) {
      if (!sddText.includes(`data-unit-id="${u.id}"`) &&
          !sddText.includes(`data-def-name="${u.id}"`)) {
        issues.push(`unit ${u.id} not referenced in sdd/mvcp/`);
      }
    }

    // integration/spec.json involves 检查
    const spec = docStore.readIntegrationSpec(ctx.pid);
    if (spec && Array.isArray(spec.cases)) {
      const ids = new Set(unitsJson.units.map(u => u.id));
      for (const c of spec.cases) {
        for (const u of (c.involves || [])) {
          if (!ids.has(u)) issues.push(`integration case ${c.id} involves unknown unit: ${u}`);
        }
      }
    }

    return { ok: issues.length === 0, issues };
  },
};

// ────────────────────────────────────────────────────────────────
// hash_contract
// ────────────────────────────────────────────────────────────────

const hash_contract = {
  name: 'hash_contract',
  description: 'canonical JSON + sha256 截 16 hex。算 Unit contract 的 hash。',
  inputSchema: {
    type: 'object',
    required: ['contract'],
    properties: {
      contract: { type: 'object' },
    },
  },
  async execute({ contract }, _ctx) {
    return { ok: true, hash: docStore.hashContract(contract) };
  },
};

// ────────────────────────────────────────────────────────────────
function _req(ctx, keys) {
  for (const k of keys) {
    if (!ctx || ctx[k] == null) {
      const { ToolMissingDependencyError } = require('./_errors');
      throw new ToolMissingDependencyError(`ctx.${k}`);
    }
  }
}

module.exports = {
  bootstrap_prd_site,
  bootstrap_sdd_site,
  write_chapter,
  write_mvcp_page,
  archive_doc,
  diff_html,
  diff_units,
  echo_diff,
  update_search_index,
  validate_prd_site,
  validate_sdd_consistency,
  hash_contract,
};