#!/usr/bin/env node

const fs = require('fs');
const os = require('os');
const path = require('path');
const { DatabaseSync } = require('node:sqlite');
const spawn = require('cross-spawn');
const { applyWorkspaceContext } = require('../mcp/src/core/runtime-context');

const PACKAGE_ROOT = path.resolve(__dirname, '..');
const { workspaceRoot: PROJECT_ROOT } = applyWorkspaceContext({ packageRoot: PACKAGE_ROOT, changeCwd: false });

function loadEnvFile(filePath) {
  if (!fs.existsSync(filePath)) return;
  for (const line of fs.readFileSync(filePath, 'utf8').split(/\r?\n/)) {
    const match = line.match(/^([A-Za-z_][A-Za-z0-9_]*)=(.*)$/);
    if (!match || process.env[match[1]] !== undefined) continue;
    let value = match[2].trim();
    if ((value.startsWith('"') && value.endsWith('"')) || (value.startsWith("'") && value.endsWith("'"))) {
      value = value.slice(1, -1);
    }
    process.env[match[1]] = value;
  }
}

function maskContact(value) {
  const text = String(value || '');
  if (text.length <= 4) return '***';
  return `${text.slice(0, 2)}***${text.slice(-2)}`;
}

function safeLabel(value) {
  return String(value || '企微客户')
    .trim()
    .replace(/[\\/:*?"<>|\r\n]+/g, '-')
    .replace(/\s+/g, '-')
    .replace(/-+/g, '-')
    .replace(/^-|-$/g, '')
    .slice(0, 24) || '企微客户';
}

function parseArgs(argv) {
  const args = { list: false, dryRun: false, customer: '', index: 0 };
  for (let i = 0; i < argv.length; i += 1) {
    if (argv[i] === '--list') args.list = true;
    else if (argv[i] === '--dry-run') args.dryRun = true;
    else if (argv[i] === '--customer') args.customer = String(argv[++i] || '').trim();
    else if (argv[i] === '--index') args.index = Number(argv[++i] || 0);
    else if (argv[i] === '--help' || argv[i] === '-h') args.help = true;
  }
  return args;
}

function readCustomerSessions({ sessionFile, dbPath }) {
  if (!fs.existsSync(sessionFile)) throw new Error('尚未创建客户 Claude Code Session');
  if (!fs.existsSync(dbPath)) throw new Error('企微 Workbench 数据库不存在');
  const state = JSON.parse(fs.readFileSync(sessionFile, 'utf8'));
  const db = new DatabaseSync(dbPath, { readOnly: true });
  try {
    return Object.entries(state.sessions || {})
      .filter(([, session]) => session.role === 'customer-agent')
      .map(([conversationId, session]) => {
        const conversation = db.prepare('SELECT contact_name, contact_id FROM conversations WHERE id=?').get(conversationId);
        return {
          conversationId,
          session,
          customerName: conversation?.contact_name || session.customerName || '未命名客户',
          maskedContact: maskContact(conversation?.contact_id),
          projectRoot: state.project?.projectRoot || PROJECT_ROOT,
        };
      })
      .sort((a, b) => String(a.customerName).localeCompare(String(b.customerName), 'zh-CN'));
  } finally {
    db.close();
  }
}

function printList(rows) {
  if (!rows.length) {
    process.stdout.write('当前没有客户 Claude Code Session。\n');
    return;
  }
  process.stdout.write('可查看的客户 Claude Code Session：\n');
  rows.forEach((row, index) => {
    const status = row.session.initialized ? '已有对话' : '尚未初始化';
    process.stdout.write(`${index + 1}. ${row.customerName}（${row.maskedContact}）· ${status}\n`);
  });
}

function selectSession(rows, args) {
  if (args.index) return rows[args.index - 1] || null;
  if (args.customer) {
    const exact = rows.filter(row => row.customerName === args.customer);
    if (exact.length === 1) return exact[0];
    const fuzzy = rows.filter(row => row.customerName.includes(args.customer));
    if (fuzzy.length === 1) return fuzzy[0];
    return null;
  }
  return rows.length === 1 ? rows[0] : null;
}

function findTranscript(sessionId) {
  const projectsRoot = path.join(os.homedir(), '.claude', 'projects');
  if (!fs.existsSync(projectsRoot)) return false;
  const target = `${sessionId}.jsonl`;
  const queue = [projectsRoot];
  while (queue.length) {
    const current = queue.shift();
    for (const entry of fs.readdirSync(current, { withFileTypes: true })) {
      const fullPath = path.join(current, entry.name);
      if (entry.isDirectory()) queue.push(fullPath);
      else if (entry.name === target) return true;
    }
  }
  return false;
}

function resolveClaudeCommand() {
  const candidates = [
    process.env.CLAUDE_CODE_EXECUTABLE,
    path.join(process.env.APPDATA || '', 'npm', 'node_modules', '@anthropic-ai', 'claude-code', 'bin', 'claude.exe'),
    process.platform === 'win32' ? 'claude.cmd' : 'claude',
  ].filter(Boolean);
  return candidates.find(candidate => !path.isAbsolute(candidate) || fs.existsSync(candidate)) || candidates.at(-1);
}

async function main() {
  loadEnvFile(path.join(PROJECT_ROOT, '.env.local'));
  const args = parseArgs(process.argv.slice(2));
  if (args.help) {
    process.stdout.write([
      '查看客户 Claude Code Session：',
      '  npm run agent:session:list',
      '  npm run agent:session -- --customer <客户名称>',
      '',
      '打开时会自动 fork 一份审阅会话；查看和追问不会污染生产客户 Session。',
      '',
    ].join('\n'));
    return;
  }

  const outputsRoot = path.resolve(process.env.QIWEI_OUTPUTS_DIR || path.join(PROJECT_ROOT, 'outputs'));
  const sessionFile = path.resolve(process.env.CLAUDE_CODE_SESSION_FILE || path.join(outputsRoot, 'messages', 'claude-code-sessions.json'));
  const dbPath = path.resolve(process.env.QIWEI_AGENT_DB_PATH || path.join(outputsRoot, 'messages', 'agent-workbench.db'));
  const rows = readCustomerSessions({ sessionFile, dbPath });

  if (args.list) {
    printList(rows);
    return;
  }

  const selected = selectSession(rows, args);
  if (!selected) {
    printList(rows);
    throw new Error('没有唯一匹配的客户，请通过 --customer <客户名称> 或 --index <序号> 选择');
  }
  if (!selected.session.initialized) throw new Error('该客户 Session 尚未产生 Claude Code 对话');

  const reviewName = `审阅-${safeLabel(selected.customerName)}`;
  const transcriptFound = findTranscript(selected.session.id);
  if (args.dryRun) {
    process.stdout.write(`${JSON.stringify({
      status: 'ok',
      customer: selected.customerName,
      maskedContact: selected.maskedContact,
      transcriptFound,
      openMode: 'forked-review',
      productionSessionProtected: true,
    }, null, 2)}\n`);
    return;
  }
  if (!transcriptFound) throw new Error('没有找到该客户的本地 Claude Code 会话记录');

  process.stdout.write(`正在打开 ${selected.customerName}（${selected.maskedContact}）的 Claude Code 审阅会话。\n`);
  process.stdout.write('系统会先 fork 审阅副本；你在其中查看或追问，不会污染生产客户 Session。\n');
  const child = spawn(resolveClaudeCommand(), [
    '--resume', selected.session.id,
    '--fork-session',
    '--name', reviewName,
  ], {
    cwd: fs.existsSync(selected.projectRoot) ? selected.projectRoot : PROJECT_ROOT,
    stdio: 'inherit',
  });
  child.on('error', error => {
    process.stderr.write(`无法打开 Claude Code：${error.message}\n`);
    process.exitCode = 1;
  });
  child.on('exit', code => { process.exitCode = Number(code || 0); });
}

if (require.main === module) {
  main().catch(error => {
    process.stderr.write(`${error.message}\n`);
    process.exitCode = 1;
  });
}

module.exports = { maskContact, parseArgs, readCustomerSessions, selectSession };