import { execFileSync } from 'node:child_process';
import fs from 'node:fs';
import os from 'node:os';
import path from 'node:path';
import { afterEach, describe, expect, it } from 'vitest';

import { getStatus, resolveBaseRefForLog, stageFiles, unstageFiles } from './service.js';

const tempDirs = [];

const createTempDir = () => {
  const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'openchamber-git-service-'));
  tempDirs.push(dir);
  return dir;
};

const runGit = (cwd, args) => execFileSync('git', args, {
  cwd,
  encoding: 'utf8',
  stdio: ['ignore', 'pipe', 'pipe'],
});

const canRunGit = () => {
  try {
    execFileSync('git', ['--version'], { stdio: 'ignore' });
    return true;
  } catch {
    return false;
  }
};

afterEach(() => {
  for (const dir of tempDirs.splice(0)) {
    fs.rmSync(dir, { recursive: true, force: true });
  }
});

describe('resolveBaseRefForLog', () => {
  it('returns the local ref unchanged when it exists, even if origin also exists', async () => {
    // Both local 'main' and 'refs/remotes/origin/main' are present.
    // The local ref takes precedence — callers that ask for 'main' get 'main'.
    const checkRef = async (ref) => ref === 'main' || ref === 'refs/remotes/origin/main';
    expect(await resolveBaseRefForLog('main', checkRef)).toBe('main');
  });

  it('falls back to origin/<from> when local ref cannot be resolved but origin can', async () => {
    // Local 'main' is absent (e.g. user never checked it out), but origin/main exists.
    const checkRef = async (ref) => ref === 'refs/remotes/origin/main';
    expect(await resolveBaseRefForLog('main', checkRef)).toBe('origin/main');
  });

  it('returns the original ref when neither local nor origin ref can be resolved', async () => {
    // Neither ref exists; return as-is so git surfaces a meaningful error.
    const checkRef = async () => false;
    expect(await resolveBaseRefForLog('nonexistent-branch', checkRef)).toBe('nonexistent-branch');
  });

  it('returns undefined when from is undefined', async () => {
    const checkRef = async () => true;
    expect(await resolveBaseRefForLog(undefined, checkRef)).toBeUndefined();
  });

  it('returns undefined when from is an empty string', async () => {
    const checkRef = async () => true;
    expect(await resolveBaseRefForLog('', checkRef)).toBeUndefined();
  });

  it('returns undefined when from is a whitespace-only string', async () => {
    const checkRef = async () => true;
    expect(await resolveBaseRefForLog('   ', checkRef)).toBeUndefined();
  });
});

describe('git index path validation', () => {
  it('rejects stage paths outside the repository before invoking git', async () => {
    await expect(stageFiles('/repo', ['../secret.txt'])).rejects.toThrow('Path is outside repository: ../secret.txt');
  });

  it('rejects unstage paths outside the repository before invoking git', async () => {
    await expect(unstageFiles('/repo', ['../secret.txt'])).rejects.toThrow('Path is outside repository: ../secret.txt');
  });
});

describe('getStatus', () => {
  it('handles repositories without upstream tracking', async () => {
    if (!canRunGit()) {
      return;
    }

    const repo = createTempDir();
    runGit(repo, ['init', '-b', 'main']);
    runGit(repo, ['config', 'user.email', 'test@example.com']);
    runGit(repo, ['config', 'user.name', 'Test User']);
    fs.writeFileSync(path.join(repo, 'README.md'), '# Test\n');
    runGit(repo, ['add', 'README.md']);
    runGit(repo, ['commit', '-m', 'Initial commit']);

    await expect(getStatus(repo)).resolves.toMatchObject({
      current: 'main',
    });
  });
});