import fs from 'node:fs/promises';
import os from 'node:os';
import path from 'node:path';

import { resolveExplicitFiles } from '../src/resolveFiles.js';

let baseDir: string;

async function writeFixture(rel: string) {
  const filePath = path.join(baseDir, rel);
  await fs.mkdir(path.dirname(filePath), { recursive: true });
  await fs.writeFile(filePath, '# fixture\n');
}

beforeEach(async () => {
  baseDir = await fs.mkdtemp(path.join(os.tmpdir(), 'resolve-files-test-'));
});

afterEach(async () => {
  await fs.rm(baseDir, { recursive: true, force: true });
});

describe('resolveExplicitFiles', () => {
  it('resolves literal paths', async () => {
    await writeFixture('docs/a.mdx');
    await expect(resolveExplicitFiles(baseDir, ['docs/a.mdx'])).resolves.toEqual(['docs/a.mdx']);
  });

  it('normalizes leading ./', async () => {
    await writeFixture('docs/a.md');
    await expect(resolveExplicitFiles(baseDir, ['./docs/a.md'])).resolves.toEqual(['docs/a.md']);
  });

  it('errors listing paths that matched nothing', async () => {
    await writeFixture('docs/a.mdx');
    await expect(
      resolveExplicitFiles(baseDir, ['docs/a.mdx', 'docs/missing.mdx', 'nope/*.mdx'])
    ).rejects.toThrow('No matching files for: docs/missing.mdx, nope/*.mdx');
  });

  it('accepts existing literal paths regardless of extension', async () => {
    await writeFixture('README.txt');
    await expect(resolveExplicitFiles(baseDir, ['README.txt'])).resolves.toEqual(['README.txt']);
  });

  it('rejects a directory passed as a literal path', async () => {
    await fs.mkdir(path.join(baseDir, 'docs'), { recursive: true });
    await expect(resolveExplicitFiles(baseDir, ['docs'])).rejects.toThrow('No matching files');
  });

  it('expands globs recursively and keeps only docs files', async () => {
    await writeFixture('docs/a.mdx');
    await writeFixture('docs/nested/deep/b.mdx');
    await writeFixture('docs/nested/notes.txt');
    await writeFixture('top.md');

    await expect(resolveExplicitFiles(baseDir, ['docs/**/*.mdx'])).resolves.toEqual([
      'docs/a.mdx',
      'docs/nested/deep/b.mdx',
    ]);
    await expect(resolveExplicitFiles(baseDir, ['*.md'])).resolves.toEqual(['top.md']);
  });

  it('dedupes overlapping literal and glob matches', async () => {
    await writeFixture('docs/a.mdx');
    await expect(resolveExplicitFiles(baseDir, ['docs/a.mdx', 'docs/*.mdx'])).resolves.toEqual([
      'docs/a.mdx',
    ]);
  });
});