'use strict';
/**
 * 老数据目录（%USERPROFILE%\.clipboard-app）→ 新默认目录（项目/exe 同级 data/）
 * 的一次性迁移。
 *
 * 三条底线：
 *   1. 迁完 config.json 里的 dataDir 必须指向新目录 —— 否则下次启动又跑回老地方；
 *   2. 新目录已经在用时不得覆盖（幂等，重复启动不会拿老库盖新库）；
 *   3. 老文件保留 —— 复制不是移动，出问题能回退。
 */
const assert = require('node:assert');
const fs = require('node:fs');
const os = require('node:os');
const path = require('node:path');

const root = fs.mkdtempSync(path.join(os.tmpdir(), 'clip-mig-'));
const home = path.join(root, 'home');
const target = path.join(root, 'Clipboard Data');    // 模拟 D:\Clipboard Data
const legacy = path.join(home, '.clipboard-app');

process.env.USERPROFILE = home;
process.env.HOME = home;
process.env.CLIPBOARD_APP_DATA_DIR = target;

const cfg = require('../config.js');

let passed = 0;
function check(name, fn) {
  try { fn(); console.log('  ok -', name); passed++; }
  catch (e) { console.error('  FAIL -', name, '\n', e.message); process.exitCode = 1; }
}

function resetTarget() {
  fs.rmSync(target, { recursive: true, force: true });
}

function seedLegacy(extraCfg) {
  fs.rmSync(legacy, { recursive: true, force: true });
  fs.mkdirSync(legacy, { recursive: true });
  fs.writeFileSync(path.join(legacy, 'history.db'), 'OLD-HISTORY');
  fs.writeFileSync(path.join(legacy, 'history.db-wal'), 'OLD-WAL');
  fs.writeFileSync(path.join(legacy, 'favorites.db'), 'OLD-FAV');
  fs.writeFileSync(path.join(legacy, 'history.db-shm'), 'OLD-SHM');
  fs.writeFileSync(
    path.join(legacy, 'config.json'),
    JSON.stringify({ maxItems: 500, pollMs: 500, theme: 'carbon', dataDir: legacy, ...extraCfg }),
  );
}

check('老数据被复制到新目录，且 dataDir 改写为新目录', () => {
  resetTarget();
  seedLegacy();
  const r = cfg.migrateLegacyData();
  assert.strictEqual(r.migrated, true);
  assert.strictEqual(fs.readFileSync(path.join(target, 'history.db'), 'utf8'), 'OLD-HISTORY');
  assert.strictEqual(fs.readFileSync(path.join(target, 'history.db-wal'), 'utf8'), 'OLD-WAL');
  assert.strictEqual(fs.readFileSync(path.join(target, 'favorites.db'), 'utf8'), 'OLD-FAV');

  const c = cfg.loadConfig();
  assert.strictEqual(path.resolve(c.dataDir), path.resolve(target), 'dataDir 必须指向新目录');
  assert.strictEqual(c.maxItems, 500, '其他设置要保留');
  assert.strictEqual(c.theme, 'carbon');
});

check('-shm 不搬（SQLite 自己重建）', () => {
  assert.ok(!fs.existsSync(path.join(target, 'history.db-shm')));
});

check('老文件保留，不是移动', () => {
  assert.ok(fs.existsSync(path.join(legacy, 'history.db')));
  assert.ok(fs.existsSync(path.join(legacy, 'config.json')));
});

check('幂等：新目录已在用时不覆盖', () => {
  fs.writeFileSync(path.join(target, 'history.db'), 'NEW-HISTORY');
  const r = cfg.migrateLegacyData();
  assert.strictEqual(r.migrated, false);
  assert.strictEqual(r.reason, 'target-in-use');
  assert.strictEqual(fs.readFileSync(path.join(target, 'history.db'), 'utf8'), 'NEW-HISTORY');
});

check('没有老数据时什么都不做', () => {
  resetTarget();
  fs.rmSync(legacy, { recursive: true, force: true });
  const r = cfg.migrateLegacyData();
  assert.strictEqual(r.migrated, false);
  assert.strictEqual(r.reason, 'nothing-to-migrate');
  assert.ok(!fs.existsSync(path.join(target, 'config.json')));
});

check('老 config 指向自定义目录时，从那个目录搬', () => {
  resetTarget();
  const custom = path.join(root, 'custom');
  fs.mkdirSync(custom, { recursive: true });
  fs.writeFileSync(path.join(custom, 'history.db'), 'CUSTOM-HISTORY');
  seedLegacy({ dataDir: custom });
  const r = cfg.migrateLegacyData();
  assert.strictEqual(r.migrated, true);
  assert.strictEqual(path.resolve(r.from), path.resolve(custom));
  assert.strictEqual(fs.readFileSync(path.join(target, 'history.db'), 'utf8'), 'CUSTOM-HISTORY');
  assert.strictEqual(path.resolve(cfg.loadConfig().dataDir), path.resolve(target));
});

check('老 config 缺 dataDir 字段时，从老目录搬（不能用 sanitize 回填的新默认目录当源）', () => {
  // sanitize 会把缺省的 dataDir 补成新默认目录（= target），拿它当 src
  // 就是"从 target 搬到 target"：什么也没搬却报 migrated，老数据永久遗留。
  resetTarget();
  fs.rmSync(legacy, { recursive: true, force: true });
  fs.mkdirSync(legacy, { recursive: true });
  fs.writeFileSync(path.join(legacy, 'history.db'), 'OLD-HISTORY');
  fs.writeFileSync(path.join(legacy, 'config.json'), JSON.stringify({ maxItems: 100, pollMs: 500 }));
  const r = cfg.migrateLegacyData();
  assert.strictEqual(r.migrated, true);
  assert.strictEqual(path.resolve(r.from), path.resolve(legacy), 'src 必须是老目录');
  assert.strictEqual(fs.readFileSync(path.join(target, 'history.db'), 'utf8'), 'OLD-HISTORY');
});

fs.rmSync(root, { recursive: true, force: true });
console.log(`\n${passed} checks passed`);