import { mkdir, readFile, rm, writeFile } from 'node:fs/promises';
import { join } from 'node:path';
import { tmpdir } from 'node:os';
import { afterEach, describe, expect, it } from 'vitest';
import { mkdtemp } from 'node:fs/promises';
import { createProjectTemplateSnapshot } from '../../shared/project-template';
import { maybeWriteProjectScaffold } from '@electron/opencode/project-scaffold';
import {
  PROJECT_TEMPLATE_SNAPSHOT_PATH,
  getProjectTemplateSnapshotPath,
  writeProjectTemplateSnapshot,
} from '@electron/opencode/project-template-snapshot';

const tempDirs: string[] = [];

afterEach(async () => {
  await Promise.all(tempDirs.splice(0).map((dir) => rm(dir, { recursive: true, force: true })));
});

async function createTempProjectDir(prefix: string) {
  const dir = await mkdtemp(join(tmpdir(), prefix));
  tempDirs.push(dir);
  return dir;
}

describe('project template snapshot helper', () => {
  it('rejects overwriting an existing valid snapshot', async () => {
    const projectPath = await createTempProjectDir('niancode-template-helper-valid-');
    const snapshot = createProjectTemplateSnapshot('standard-dev', '2026-07-01T00:00:00.000Z');

    await writeProjectTemplateSnapshot(projectPath, snapshot);

    await expect(writeProjectTemplateSnapshot(projectPath, snapshot)).rejects.toThrow(PROJECT_TEMPLATE_SNAPSHOT_PATH);
    await expect(writeProjectTemplateSnapshot(projectPath, snapshot)).rejects.toThrow(/already exists/i);
  });

  it('rejects overwriting an existing invalid snapshot and preserves its contents', async () => {
    const projectPath = await createTempProjectDir('niancode-template-helper-invalid-');
    const snapshotPath = getProjectTemplateSnapshotPath(projectPath);
    await mkdir(join(projectPath, '.niancode'), { recursive: true });
    await writeFile(snapshotPath, '{"broken":true}\n', 'utf8');

    const snapshot = createProjectTemplateSnapshot('standard-dev', '2026-07-01T00:00:00.000Z');

    await expect(writeProjectTemplateSnapshot(projectPath, snapshot)).rejects.toThrow(/already exists/i);
    await expect(readFile(snapshotPath, 'utf8')).resolves.toBe('{"broken":true}\n');
  });

  it('does not overwrite an existing scaffold file and preserves its contents', async () => {
    const projectPath = await createTempProjectDir('niancode-template-helper-scaffold-');
    const snapshot = createProjectTemplateSnapshot('web-mini-game-course', '2026-07-01T00:00:00.000Z');
    await mkdir(join(projectPath, 'src'), { recursive: true });
    await writeFile(join(projectPath, 'src', 'main.ts'), '// keep me\n', 'utf8');

    const result = await maybeWriteProjectScaffold(projectPath, snapshot);

    expect(result).toEqual({
      status: 'skipped_existing_files',
      files: ['src/main.ts'],
    });
    await expect(readFile(join(projectPath, 'src', 'main.ts'), 'utf8')).resolves.toBe('// keep me\n');
  });

  it('allows scaffold generation when the project root only contains ignorable entries', async () => {
    const projectPath = await createTempProjectDir('niancode-template-helper-ignorable-');
    const snapshot = createProjectTemplateSnapshot('web-mini-game-course', '2026-07-01T00:00:00.000Z');
    await mkdir(join(projectPath, '.git'), { recursive: true });
    await mkdir(join(projectPath, '.niancode'), { recursive: true });
    await writeFile(join(projectPath, '.DS_Store'), '', 'utf8');
    await writeFile(join(projectPath, 'Thumbs.db'), '', 'utf8');

    const result = await maybeWriteProjectScaffold(projectPath, snapshot);

    expect(result.status).toBe('generated');
    await expect(readFile(join(projectPath, 'package.json'), 'utf8')).resolves.toContain('"phaser"');
  });

  it('treats extra files inside an existing scaffold root directory as non-empty project content', async () => {
    const projectPath = await createTempProjectDir('niancode-template-helper-non-empty-src-');
    const snapshot = createProjectTemplateSnapshot('web-mini-game-course', '2026-07-01T00:00:00.000Z');
    await mkdir(join(projectPath, 'src'), { recursive: true });
    await writeFile(join(projectPath, 'src', 'utils.ts'), 'export const noop = () => {};\n', 'utf8');

    const result = await maybeWriteProjectScaffold(projectPath, snapshot);

    expect(result).toEqual({
      status: 'skipped_non_empty',
      entries: ['src/utils.ts'],
    });
    await expect(readFile(join(projectPath, 'src', 'utils.ts'), 'utf8')).resolves.toContain('noop');
  });

  it('treats nested extra files inside an existing scaffold root directory as non-empty project content', async () => {
    const projectPath = await createTempProjectDir('niancode-template-helper-nested-src-');
    const snapshot = createProjectTemplateSnapshot('web-mini-game-course', '2026-07-01T00:00:00.000Z');
    await mkdir(join(projectPath, 'src', 'assets'), { recursive: true });
    await writeFile(join(projectPath, 'src', 'assets', 'existing.png'), 'fake-png', 'utf8');

    const result = await maybeWriteProjectScaffold(projectPath, snapshot);

    expect(result).toEqual({
      status: 'skipped_non_empty',
      entries: ['src/assets/existing.png'],
    });
  });

  it('treats a root file named src as non-empty project content', async () => {
    const projectPath = await createTempProjectDir('niancode-template-helper-src-file-');
    const snapshot = createProjectTemplateSnapshot('web-mini-game-course', '2026-07-01T00:00:00.000Z');
    await writeFile(join(projectPath, 'src'), 'not-a-directory\n', 'utf8');

    const result = await maybeWriteProjectScaffold(projectPath, snapshot);

    expect(result).toEqual({
      status: 'skipped_non_empty',
      entries: ['src'],
    });
  });

  it('writes the Phaser starter scaffold for an empty mini-game project', async () => {
    const projectPath = await createTempProjectDir('niancode-template-helper-generated-');
    const snapshot = createProjectTemplateSnapshot('web-mini-game-course', '2026-07-01T00:00:00.000Z');

    const result = await maybeWriteProjectScaffold(projectPath, snapshot);

    expect(result.status).toBe('generated');
    if (result.status !== 'generated') {
      throw new Error(`Expected generated scaffold, received ${result.status}`);
    }
    expect(result.files).toEqual([
      'ASSET_PLAN.md',
      'GDD.md',
      'README.md',
      'RELEASE_CHECKLIST.md',
      'PRODUCT_OVERVIEW.md',
      'TASKS.md',
      'index.html',
      'package.json',
      'src/main.ts',
      'src/styles.css',
      'tsconfig.json',
      'vite.config.ts',
    ]);

    const packageJson = JSON.parse(await readFile(join(projectPath, 'package.json'), 'utf8')) as {
      scripts: Record<string, string>;
      dependencies: Record<string, string>;
      devDependencies: Record<string, string>;
    };
    expect(packageJson.scripts).toEqual({
      dev: 'vite --host 0.0.0.0',
      build: 'tsc && vite build',
      preview: 'vite preview --host 0.0.0.0',
    });
    expect(packageJson.dependencies.phaser).toBe('3.90.0');
    expect(packageJson.devDependencies.typescript).toMatch(/^\^[0-9]+\.[0-9]+\.[0-9]+$/);
    expect(packageJson.devDependencies.vite).toMatch(/^\^[0-9]+\.[0-9]+\.[0-9]+$/);

    await expect(readFile(join(projectPath, 'src', 'main.ts'), 'utf8')).resolves.toContain('GDD.md');
    await expect(readFile(join(projectPath, 'src', 'main.ts'), 'utf8')).resolves.toContain('Phaser.Scale.FIT');
    await expect(readFile(join(projectPath, 'GDD.md'), 'utf8')).resolves.toContain('## 5. 当前系统');
    await expect(readFile(join(projectPath, 'TASKS.md'), 'utf8')).resolves.toContain('## Last verified');
    await expect(readFile(join(projectPath, 'PRODUCT_OVERVIEW.md'), 'utf8')).resolves.toContain('## 5. 对外介绍与运营表达');
  });
});