'use strict';
/**
 * 回归测试：v1 -> v2 迁移
 *
 * 曾经的 bug：migrate() 用 STEPS[v - 1] 取步骤，但 STEPS[0] 就是 v1->v2 的步骤，
 * 所以 v=2 时取到的是 STEPS[1] === undefined，整个 FTS5 迁移从来没跑过。
 * 表现：clips_fts 永远不存在，搜索一直静默退回 LIKE 全表扫描。
 */
const assert = require('node:assert');
const fs = require('node:fs');
const os = require('node:os');
const path = require('node:path');
const Database = require('better-sqlite3');
const { migrate, STEPS } = require('../lib/migrate.js');

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

function freshDb() {
  const tmp = fs.mkdtempSync(path.join(os.tmpdir(), 'clip-mig2-'));
  const db = new Database(path.join(tmp, 'h.db'));
  db.exec(`CREATE TABLE clips (
    id INTEGER PRIMARY KEY AUTOINCREMENT, type TEXT, text TEXT,
    top_at REAL, created_at REAL NOT NULL DEFAULT 0)`);
  return db;
}

check('STEPS[0] is the v1->v2 step (index maps version-2, not version-1)', () => {
  assert.strictEqual(typeof STEPS[0], 'function');
  assert.match(STEPS[0].name, /v1_to_v2/);
});

// 探测这个 SQLite 构建是否带 FTS5；没有的话下面的断言换成"优雅降级"
let fts5 = true;
{
  const db = freshDb();
  try { db.exec(`CREATE VIRTUAL TABLE t USING fts5(x)`); } catch (_) { fts5 = false; }
  db.close();
}

check('migrate actually reaches v2 and reports it', () => {
  const db = freshDb();
  const reached = migrate(db, 1, 2);
  if (fts5) {
    assert.strictEqual(reached, 2, '迁移应到达 v2');
    assert.strictEqual(db.pragma('user_version', { simple: true }), 2);
  } else {
    assert.strictEqual(reached, 1, '没有 FTS5 时应停在 v1，而不是谎报成功');
  }
  db.close();
});

if (fts5) {
  check('clips_fts exists and is searchable after migrate', () => {
    const db = freshDb();
    db.prepare('INSERT INTO clips(type,text) VALUES(?,?)').run('text', 'hello world');
    migrate(db, 1, 2);
    const rows = db.prepare(`SELECT rowid FROM clips_fts WHERE clips_fts MATCH 'hello'`).all();
    assert.strictEqual(rows.length, 1, '已有数据应被回填进 FTS 索引');
    db.close();
  });

  check('migrate is idempotent across restarts (no duplicate index entries)', () => {
    const db = freshDb();
    db.prepare('INSERT INTO clips(type,text) VALUES(?,?)').run('text', 'hello world');
    for (let launch = 0; launch < 3; launch++) migrate(db, 1, 2);
    const n = db.prepare(`SELECT count(*) c FROM clips_fts WHERE clips_fts MATCH 'hello'`).get().c;
    assert.strictEqual(n, 1, '重复启动不应重复回填');
    db.exec(`INSERT INTO clips_fts(clips_fts) VALUES('integrity-check')`);
    db.close();
  });

  check('user_version short-circuits the backfill on subsequent runs', () => {
    const db = freshDb();
    migrate(db, 1, 2);
    // 直接往 clips 插一行但绕开触发器是做不到的，所以改为验证：
    // 第二次 migrate 不再执行回填（否则这行会被索引两次）
    db.prepare('INSERT INTO clips(type,text) VALUES(?,?)').run('text', 'unique token zzz');
    migrate(db, 1, 2);
    const n = db.prepare(`SELECT count(*) c FROM clips_fts WHERE clips_fts MATCH 'zzz'`).get().c;
    assert.strictEqual(n, 1);
    db.close();
  });

  check('AFTER UPDATE trigger skips FTS churn when only top_at changes', () => {
    const db = freshDb();
    db.prepare('INSERT INTO clips(type,text) VALUES(?,?)').run('text', 'hello world');
    migrate(db, 1, 2);
    db.prepare('UPDATE clips SET top_at = ? WHERE id = 1').run(123);
    assert.strictEqual(
      db.prepare(`SELECT count(*) c FROM clips_fts WHERE clips_fts MATCH 'hello'`).get().c, 1,
      '置顶不应影响可搜索性');
    db.exec(`INSERT INTO clips_fts(clips_fts) VALUES('integrity-check')`);
    db.close();
  });

  check('AFTER UPDATE trigger still re-indexes when text changes', () => {
    const db = freshDb();
    db.prepare('INSERT INTO clips(type,text) VALUES(?,?)').run('text', 'hello world');
    migrate(db, 1, 2);
    db.prepare('UPDATE clips SET text = ? WHERE id = 1').run('goodbye moon');
    assert.strictEqual(db.prepare(`SELECT count(*) c FROM clips_fts WHERE clips_fts MATCH 'hello'`).get().c, 0);
    assert.strictEqual(db.prepare(`SELECT count(*) c FROM clips_fts WHERE clips_fts MATCH 'goodbye'`).get().c, 1);
    db.close();
  });

  check('DELETE keeps the FTS index consistent', () => {
    const db = freshDb();
    db.prepare('INSERT INTO clips(type,text) VALUES(?,?)').run('text', 'hello world');
    migrate(db, 1, 2);
    db.prepare('DELETE FROM clips WHERE id = 1').run();
    assert.strictEqual(db.prepare(`SELECT count(*) c FROM clips_fts WHERE clips_fts MATCH 'hello'`).get().c, 0);
    db.exec(`INSERT INTO clips_fts(clips_fts) VALUES('integrity-check')`);
    db.close();
  });
} else {
  console.log('  SKIP - FTS5 unavailable in this SQLite build');
}

check('migrate on a broken db degrades instead of throwing', () => {
  const bad = { pragma() { throw new Error('nope'); }, exec() { throw new Error('nope'); } };
  assert.strictEqual(migrate(bad, 1, 2), 1);
});

console.log(`\n${passed} checks passed`);