import { test } from 'node:test';
import assert from 'node:assert/strict';
import { execFileSync } from 'node:child_process';
import { existsSync, mkdtempSync, rmSync, writeFileSync } from 'node:fs';
import { tmpdir } from 'node:os';
import { join } from 'node:path';
import { createWorktree, worktreeDiff, removeWorktree, worktreeDirFor, branchFor } from '../src/executor/worktree.js';

function gitSync(cwd: string, args: string[]): string {
  return execFileSync('git', args, { cwd, encoding: 'utf8' });
}

/** /tmp 下建一个带 1 个 commit 的真实 git repo（main 分支） */
function makeRepo(): string {
  const repo = mkdtempSync(join(tmpdir(), 'maestro-wt-repo-'));
  gitSync(repo, ['init', '-b', 'main']);
  gitSync(repo, ['config', 'user.name', 'maestro-test']);
  gitSync(repo, ['config', 'user.email', 'test@maestro.local']);
  writeFileSync(join(repo, 'README.md'), '# demo\n');
  gitSync(repo, ['add', '-A']);
  gitSync(repo, ['commit', '-m', 'init']);
  return repo;
}

test('worktree：create / diff / remove 在真实 git repo 上工作', async (t) => {
  // worktree 根目录隔离到临时 MAESTRO_DATA_DIR，不碰 ~/.maestro
  const dataDir = mkdtempSync(join(tmpdir(), 'maestro-wt-data-'));
  const prevDataDir = process.env.MAESTRO_DATA_DIR;
  process.env.MAESTRO_DATA_DIR = dataDir;
  const repo = makeRepo();
  t.after(() => {
    if (prevDataDir === undefined) delete process.env.MAESTRO_DATA_DIR;
    else process.env.MAESTRO_DATA_DIR = prevDataDir;
    rmSync(dataDir, { recursive: true, force: true });
    rmSync(repo, { recursive: true, force: true });
  });

  const taskId = 'tsk_test123';

  // 1) 创建：目录与分支符合约定
  const wt = await createWorktree(repo, taskId, 'main');
  assert.equal(wt.branch, branchFor(taskId));
  assert.equal(wt.dir, worktreeDirFor(repo, taskId));
  assert.ok(existsSync(join(wt.dir, 'README.md')), 'worktree 应检出 README.md');
  const head = gitSync(wt.dir, ['rev-parse', '--abbrev-ref', 'HEAD']).trim();
  assert.equal(head, wt.branch);

  // 2) 空分支 diff：无 commit、无摘要
  const empty = await worktreeDiff(repo, wt.dir, wt.branch, 'main');
  assert.equal(empty.commits.length, 0);
  assert.equal(empty.diffSummary, '');

  // 3) 在 worktree 提交一笔改动 → diff 能看到 commit 与 --stat 摘要
  writeFileSync(join(wt.dir, 'README.md'), '# demo\nhello maestro\n');
  gitSync(wt.dir, ['add', '-A']);
  gitSync(wt.dir, ['commit', '-m', `maestro(${taskId}): tweak readme`]);
  const diff = await worktreeDiff(repo, wt.dir, wt.branch, 'main');
  assert.equal(diff.commits.length, 1);
  assert.ok(diff.commits[0].includes(taskId), `commit 行应含任务 id：${diff.commits[0]}`);
  assert.ok(diff.diffSummary.includes('README.md'), `diffSummary 应含文件名：${diff.diffSummary}`);

  // 4) 已存在同名 worktree/分支时重建（重试场景）：从 main 干净重来
  const wt2 = await createWorktree(repo, taskId, 'main');
  assert.equal(wt2.dir, wt.dir);
  const diff2 = await worktreeDiff(repo, wt2.dir, wt2.branch, 'main');
  assert.equal(diff2.commits.length, 0, '重建后分支应回到 baseBranch，无旧 commit');

  // 5) remove：目录与注册项移除，主 repo 不受影响
  await removeWorktree(repo, wt2.dir);
  assert.ok(!existsSync(wt2.dir), 'worktree 目录应被移除');
  const list = gitSync(repo, ['worktree', 'list']);
  assert.ok(!list.includes(taskId), 'git worktree list 不应再含该任务');
  assert.ok(existsSync(join(repo, 'README.md')), '主 repo 不受影响');
});

test('worktree：错误透传（不存在的 baseBranch）', async (t) => {
  const dataDir = mkdtempSync(join(tmpdir(), 'maestro-wt-data2-'));
  const prevDataDir = process.env.MAESTRO_DATA_DIR;
  process.env.MAESTRO_DATA_DIR = dataDir;
  const repo = makeRepo();
  t.after(() => {
    if (prevDataDir === undefined) delete process.env.MAESTRO_DATA_DIR;
    else process.env.MAESTRO_DATA_DIR = prevDataDir;
    rmSync(dataDir, { recursive: true, force: true });
    rmSync(repo, { recursive: true, force: true });
  });

  await assert.rejects(
    () => createWorktree(repo, 'tsk_badbase', 'no-such-branch'),
    /git worktree add/,
  );
});