// provider_sync.js —— 一键把历史会话同步到「当前账号」的 provider，使其在 Codex 侧栏重新显示。
// 复刻 CodexPlusPlus 的 provider-sync：改 rollout 首行 provider + state DB(provider/has_user_event/cwd)。
// 必须在 Codex 已退出时运行。数据库用纯 JS 的 sql.js（免原生编译，跨平台）。
const fs = require("fs");
const path = require("path");
const os = require("os");
const { execFileSync } = require("child_process");
const initSqlJs = require("sql.js");

const CODEX_HOME = path.join(os.homedir(), ".codex");

// 检测 Codex 是否在运行（尽力而为，跨平台）
function codexRunning() {
  try {
    if (process.platform === "darwin") {
      return execFileSync("pgrep", ["-f", "Codex.app/Contents/MacOS/Codex"], { encoding: "utf-8" }).trim().length > 0;
    }
    if (process.platform === "win32") {
      return /Codex\.exe/i.test(execFileSync("tasklist", [], { encoding: "utf-8" }));
    }
  } catch {
    /* pgrep 无匹配时退出码非 0，视为未运行 */
  }
  return false;
}

// 目标 provider = config.toml 根级 model_provider，缺省 openai
function targetProvider() {
  try {
    const head = fs.readFileSync(path.join(CODEX_HOME, "config.toml"), "utf-8").split("\n[")[0];
    const m = head.match(/^\s*model_provider\s*=\s*["']([^"']+)/m);
    if (m) return m[1];
  } catch {}
  return "openai";
}

function findRollouts() {
  const out = [];
  for (const root of [path.join(CODEX_HOME, "sessions"), path.join(CODEX_HOME, "archived_sessions")]) {
    const walk = (dir) => {
      let ents;
      try {
        ents = fs.readdirSync(dir, { withFileTypes: true });
      } catch {
        return;
      }
      for (const e of ents) {
        const full = path.join(dir, e.name);
        if (e.isDirectory()) walk(full);
        else if (e.isFile() && e.name.startsWith("rollout-") && e.name.endsWith(".jsonl")) out.push(full);
      }
    };
    walk(root);
  }
  return out;
}

function ts() {
  const d = new Date();
  const p = (n) => String(n).padStart(2, "0");
  return `${d.getFullYear()}${p(d.getMonth() + 1)}${p(d.getDate())}-${p(d.getHours())}${p(d.getMinutes())}${p(d.getSeconds())}`;
}

async function syncProviderToCurrent(log = () => {}, onProgress = () => {}) {
  if (codexRunning()) throw new Error("检测到 Codex 正在运行，请先完全退出 Codex 再同步。");
  const target = targetProvider();
  log(`目标 provider：${target}`);
  onProgress({ phase: "备份中", done: 0, total: 0 });

  // 1) 备份
  const backup = path.join(CODEX_HOME, "backups_state", "provider-sync", ts());
  fs.mkdirSync(backup, { recursive: true });
  for (const name of ["config.toml", ".codex-global-state.json", ".codex-global-state.json.bak"]) {
    const src = path.join(CODEX_HOME, name);
    if (fs.existsSync(src)) fs.copyFileSync(src, path.join(backup, name));
  }
  for (const db of fs.readdirSync(CODEX_HOME).filter((f) => /^state_.*\.sqlite/.test(f))) {
    fs.copyFileSync(path.join(CODEX_HOME, db), path.join(backup, db));
  }
  log(`已备份到 ${backup}`);

  // 2) 遍历 rollout：改首行 provider，收集 thread_id / cwd / has_user_event
  const userEventIds = new Set();
  const cwdById = {};
  let changedFiles = 0;
  const rolloutFiles = findRollouts();
  const rtotal = rolloutFiles.length;
  let ri = 0;
  for (const file of rolloutFiles) {
    ri++;
    if (ri % 5 === 0 || ri === rtotal) onProgress({ phase: "改写会话文件", done: ri, total: rtotal });
    let lines;
    try {
      lines = fs.readFileSync(file, "utf-8").split(/(?<=\n)/); // 保留换行
    } catch {
      continue;
    }
    if (!lines.length) continue;
    const blob = lines.join("");
    const hasUE = blob.includes('"user_message"') || blob.includes('"user_input"');
    let tid = null;
    let rewrote = false;
    for (let i = 0; i < lines.length; i++) {
      const line = lines[i];
      if (!line.trim()) continue;
      let rec;
      try {
        rec = JSON.parse(line);
      } catch {
        continue;
      }
      if (rec.type === "session_meta" && rec.payload && typeof rec.payload === "object") {
        tid = rec.payload.id || rec.payload.session_id || null;
        const cwd = rec.payload.cwd;
        if (tid && cwd) cwdById[tid] = cwd;
        if (rec.payload.model_provider !== target) {
          rec.payload.model_provider = target;
          lines[i] = JSON.stringify(rec) + "\n";
          rewrote = true;
        }
        break;
      }
    }
    if (rewrote) {
      fs.writeFileSync(file, lines.join(""), "utf-8");
      changedFiles++;
    }
    if (tid && hasUE) userEventIds.add(tid);
  }
  log(`改写 rollout 文件：${changedFiles} 个；含用户消息的会话：${userEventIds.size} 条`);

  // 3) 更新所有 state_*.sqlite
  onProgress({ phase: "更新数据库", done: 0, total: 0 });
  const SQL = await initSqlJs({
    // wasm 恒在【包内】node_modules（热更包不含 node_modules），故用 BUNDLE_ROOT 而非 __dirname
    locateFile: (f) =>
      path.join(global.__BUNDLE_ROOT__ || path.join(__dirname, "..", ".."),
        "node_modules", "sql.js", "dist", f),
  });
  let provRows = 0;
  let ueRows = 0;
  let cwdRows = 0;
  for (const name of fs.readdirSync(CODEX_HOME).filter((f) => /^state_.*\.sqlite$/.test(f))) {
    const dbPath = path.join(CODEX_HOME, name);
    let db;
    try {
      db = new SQL.Database(fs.readFileSync(dbPath));
      const tbl = db.exec("SELECT name FROM sqlite_master WHERE type='table' AND name='threads'");
      if (!tbl.length) {
        db.close();
        continue;
      }
      const cols = new Set(db.exec("PRAGMA table_info(threads)")[0].values.map((r) => r[1]));
      if (!cols.has("model_provider")) {
        db.close();
        continue;
      }
      db.run("UPDATE threads SET model_provider=? WHERE COALESCE(model_provider,'')<>?", [target, target]);
      provRows += db.getRowsModified();
      if (cols.has("has_user_event")) {
        for (const tid of userEventIds) {
          db.run("UPDATE threads SET has_user_event=1 WHERE id=? AND COALESCE(has_user_event,0)<>1", [tid]);
          ueRows += db.getRowsModified();
        }
      }
      if (cols.has("cwd")) {
        for (const tid of Object.keys(cwdById)) {
          db.run("UPDATE threads SET cwd=? WHERE id=? AND COALESCE(cwd,'')<>?", [cwdById[tid], tid, cwdById[tid]]);
          cwdRows += db.getRowsModified();
        }
      }
      fs.writeFileSync(dbPath, Buffer.from(db.export()));
      db.close();
    } catch (e) {
      if (db) try { db.close(); } catch {}
      log(`  数据库跳过 ${name}：${e.message || e}`);
    }
  }
  log(`数据库更新：provider ${provRows} 行、has_user_event ${ueRows} 行、cwd ${cwdRows} 行`);
  onProgress({ phase: "完成", done: 0, total: 0 });

  return {
    target,
    totalConversations: rtotal,
    changedFiles,
    userEvents: userEventIds.size,
    provRows,
    ueRows,
    cwdRows,
    backup,
  };
}

module.exports = { syncProviderToCurrent, codexRunning, targetProvider };