import fs from 'node:fs';
import path from 'node:path';
import { fileURLToPath } from 'node:url';
import {
  ensurePublishSkillInstalled,
  PUBLISH_SKILL_NAME,
  renderPublishSkill,
  resolvePublicBaseUrl,
} from './user-publish.mjs';

const __dirname = path.dirname(fileURLToPath(import.meta.url));

export const PAGE_DATA_COLLECT_SKILL_NAME = 'page-data-collect';
export const EXCEL_ANALYST_SKILL_NAME = 'excel-analyst';
export const IMAGE_GENERATION_SKILL_NAME = 'image-generation';

export const DEFAULT_USER_SKILLS = {
  web: true,
  search: true,
  'search-enhanced': false,
  [EXCEL_ANALYST_SKILL_NAME]: false,
  'schedule-assistant': true,
  'service-integration-smoke': true,
  'form-builder': true,
  'table-viewer': true,
  'product-campaign-page': true,
  'docx-generate': true,
  'long-image-download': true,
  [IMAGE_GENERATION_SKILL_NAME]: true,
  [PAGE_DATA_COLLECT_SKILL_NAME]: true,
  [PUBLISH_SKILL_NAME]: false,
};

/** Optional presets for admin role configuration (creator / developer). */
export const USER_ROLE_SKILL_PRESETS = {
  user: DEFAULT_USER_SKILLS,
  creator: {
    ...DEFAULT_USER_SKILLS,
    [PUBLISH_SKILL_NAME]: true,
    kanban: true,
    timeline: true,
  },
  developer: {
    ...DEFAULT_USER_SKILLS,
    git: true,
    'diff-viewer': true,
    'code-playground': true,
    'test-runner': true,
  },
};

export function parseSkillFrontmatter(content) {
  const match = content.match(/^---\r?\n([\s\S]*?)\r?\n---/);
  if (!match) return { name: null, description: '' };
  const block = match[1];
  const name = block.match(/^name:\s*(.+)$/m)?.[1]?.trim() ?? null;
  const description = block.match(/^description:\s*(.+)$/m)?.[1]?.trim() ?? '';
  return { name, description };
}

function parseManifestScalar(value) {
  const text = String(value ?? '').trim();
  if (!text) return '';
  if ((text.startsWith('"') && text.endsWith('"')) || (text.startsWith("'") && text.endsWith("'"))) {
    return text.slice(1, -1);
  }
  if (/^-?\d+(?:\.\d+)?$/.test(text)) return Number(text);
  if (/^(?:true|false)$/i.test(text)) return text.toLowerCase() === 'true';
  if (/^(?:null|~)$/i.test(text)) return null;
  return text;
}

/** Parse the small YAML subset used by platform skill manifests without adding a runtime dependency. */
export function parseSkillManifest(content) {
  const lines = String(content ?? '').split(/\r?\n/);
  const root = {};
  const stack = [{ indent: -1, value: root }];

  for (let index = 0; index < lines.length; index += 1) {
    const raw = lines[index];
    const trimmed = raw.trim();
    if (!trimmed || trimmed.startsWith('#')) continue;
    const indent = raw.match(/^\s*/)?.[0]?.length ?? 0;
    while (stack.length > 1 && stack.at(-1).indent >= indent) stack.pop();
    const parent = stack.at(-1).value;

    if (trimmed.startsWith('- ')) {
      if (!Array.isArray(parent)) throw new Error(`Invalid manifest list at line ${index + 1}`);
      parent.push(parseManifestScalar(trimmed.slice(2)));
      continue;
    }

    const separator = trimmed.indexOf(':');
    if (separator <= 0 || Array.isArray(parent)) {
      throw new Error(`Invalid manifest entry at line ${index + 1}`);
    }
    const key = trimmed.slice(0, separator).trim();
    const value = trimmed.slice(separator + 1).trim();
    if (value) {
      parent[key] = parseManifestScalar(value);
      continue;
    }

    let nextTrimmed = '';
    for (let cursor = index + 1; cursor < lines.length; cursor += 1) {
      nextTrimmed = lines[cursor].trim();
      if (nextTrimmed && !nextTrimmed.startsWith('#')) break;
    }
    const child = nextTrimmed.startsWith('- ') ? [] : {};
    parent[key] = child;
    stack.push({ indent, value: child });
  }

  return root;
}

export function listPlatformSkillCatalog(h5Root = __dirname) {
  const skillsRoot = path.join(h5Root, 'skills');
  if (!fs.existsSync(skillsRoot)) return [];

  const catalog = [];
  for (const entry of fs.readdirSync(skillsRoot, { withFileTypes: true })) {
    if (!entry.isDirectory()) continue;
    const skillPath = path.join(skillsRoot, entry.name, 'SKILL.md');
    if (!fs.existsSync(skillPath)) continue;
    const raw = fs.readFileSync(skillPath, 'utf8');
    const meta = parseSkillFrontmatter(raw);
    const manifestPath = path.join(skillsRoot, entry.name, 'skill.yaml');
    let manifest = null;
    if (fs.existsSync(manifestPath)) {
      try {
        manifest = parseSkillManifest(fs.readFileSync(manifestPath, 'utf8'));
      } catch {
        manifest = null;
      }
    }
    const name = manifest?.name || meta.name || entry.name;
    catalog.push({
      name,
      dirName: entry.name,
      label: manifest?.label || name,
      description: manifest?.description || meta.description || '平台通用技能',
      version: manifest?.version ?? null,
      executors: Array.isArray(manifest?.executors) ? manifest.executors : ['goose'],
      manifest,
      category: 'platform',
      requiresPublish: name === PUBLISH_SKILL_NAME || name === PAGE_DATA_COLLECT_SKILL_NAME,
    });
  }
  return catalog.sort((a, b) => a.name.localeCompare(b.name));
}

export function catalogSkillNames(catalog) {
  return catalog.map((item) => item.name);
}

export function isValidSkillName(catalog, name) {
  return catalog.some((item) => item.name === name);
}

export function normalizeSkillPatch(catalog, patch) {
  const normalized = {};
  for (const [key, value] of Object.entries(patch ?? {})) {
    if (!isValidSkillName(catalog, key)) continue;
    normalized[key] = Boolean(value);
  }
  return normalized;
}

export function resolveSkillMap(roleGrants, userOverrides, catalog) {
  const resolved = {};
  for (const item of catalog) {
    const key = item.name;
    if (key in userOverrides) {
      resolved[key] = userOverrides[key];
    } else if (key in roleGrants) {
      resolved[key] = roleGrants[key];
    } else {
      resolved[key] = DEFAULT_USER_SKILLS[key] ?? false;
    }
  }
  return resolved;
}

export function grantedSkillNames(skillMap) {
  return Object.entries(skillMap)
    .filter(([, enabled]) => enabled)
    .map(([name]) => name);
}

export function applySkillGrantsToCapabilities(capabilities, skillMap) {
  const effective = { ...capabilities };
  const enabled = grantedSkillNames(skillMap);
  if (enabled.length > 0) {
    effective.skills = true;
  }
  if (enabled.includes(PUBLISH_SKILL_NAME) || enabled.includes(PAGE_DATA_COLLECT_SKILL_NAME)) {
    effective.static_publish = true;
  }
  // Excel is intentionally a single MemindAdm skill switch. The internal
  // capability is derived here instead of appearing as a second admin toggle.
  effective.excel_analysis = enabled.includes(EXCEL_ANALYST_SKILL_NAME);
  return effective;
}

function copySkillTree(srcDir, destDir) {
  fs.mkdirSync(destDir, { recursive: true });
  for (const entry of fs.readdirSync(srcDir, { withFileTypes: true })) {
    const from = path.join(srcDir, entry.name);
    const to = path.join(destDir, entry.name);
    if (entry.isDirectory()) {
      copySkillTree(from, to);
    } else {
      fs.copyFileSync(from, to);
    }
  }
}

const SKILL_SYNC_LOCK_RETRY_MS = 25;
const SKILL_SYNC_LOCK_TIMEOUT_MS = 10_000;
const SKILL_SYNC_LOCK_STALE_MS = 60_000;
const skillSyncWaitBuffer = new Int32Array(new SharedArrayBuffer(4));

function withWorkspaceSkillSyncLock(publishDir, callback) {
  const agentsRoot = path.join(publishDir, '.agents');
  const lockDir = path.join(agentsRoot, '.skills-sync.lock');
  fs.mkdirSync(agentsRoot, { recursive: true });
  const startedAt = Date.now();

  while (true) {
    try {
      fs.mkdirSync(lockDir);
      break;
    } catch (error) {
      if (error?.code !== 'EEXIST') throw error;
      try {
        const ageMs = Date.now() - fs.statSync(lockDir).mtimeMs;
        if (ageMs > SKILL_SYNC_LOCK_STALE_MS) {
          fs.rmSync(lockDir, { recursive: true, force: true });
          continue;
        }
      } catch (statError) {
        if (statError?.code === 'ENOENT') continue;
        throw statError;
      }
      if (Date.now() - startedAt >= SKILL_SYNC_LOCK_TIMEOUT_MS) {
        throw new Error(`Timed out waiting for workspace skill sync lock: ${publishDir}`);
      }
      Atomics.wait(skillSyncWaitBuffer, 0, 0, SKILL_SYNC_LOCK_RETRY_MS);
    }
  }

  try {
    return callback();
  } finally {
    fs.rmSync(lockDir, { recursive: true, force: true });
  }
}

export function syncSkillsToWorkspace({
  h5Root,
  publishDir,
  skillMap,
  catalog,
  user,
  publicBaseUrl,
}) {
  return withWorkspaceSkillSyncLock(publishDir, () => {
    const enabled = new Set(grantedSkillNames(skillMap));
    const platformNames = new Set(catalog.map((item) => item.name));
    const agentsSkills = path.join(publishDir, '.agents', 'skills');

    if (fs.existsSync(agentsSkills)) {
      for (const entry of fs.readdirSync(agentsSkills, { withFileTypes: true })) {
        if (!entry.isDirectory()) continue;
        const skillName = entry.name;
        const catalogItem = catalog.find((item) => item.name === skillName || item.dirName === skillName);
        const resolvedName = catalogItem?.name ?? skillName;
        if (platformNames.has(resolvedName) && !enabled.has(resolvedName)) {
          fs.rmSync(path.join(agentsSkills, entry.name), { recursive: true, force: true });
        }
      }
    }

    for (const item of catalog) {
      if (!enabled.has(item.name)) continue;
      const srcDir = path.join(h5Root, 'skills', item.dirName);
      const destDir = path.join(agentsSkills, item.name);
      if (item.name === PUBLISH_SKILL_NAME && user) {
        ensurePublishSkillInstalled(publishDir, {
          slug: String(user.id).trim().toLowerCase(),
          username: user.username ? String(user.username).trim().toLowerCase() : undefined,
          publicBaseUrl,
          publishDir,
        });
        continue;
      }
      if (fs.existsSync(srcDir)) {
        if (fs.existsSync(destDir)) fs.rmSync(destDir, { recursive: true, force: true });
        copySkillTree(srcDir, destDir);
      }
    }
  });
}