import { afterEach, beforeEach, describe, expect, it } from 'bun:test';
import { mkdtemp, readFile, readdir, rm, writeFile } from 'node:fs/promises';
import { tmpdir } from 'node:os';
import { join } from 'node:path';
import { parseChangeset } from '../../module/versioning/changeset-version';
import { handleModuleChangeset } from './module-changeset';

let dir: string;
beforeEach(async () => {
  dir = await mkdtemp(join(tmpdir(), 'celilo-cs-'));
  await writeFile(
    join(dir, 'manifest.yml'),
    'celilo_contract: "1.0"\nid: lunacycle\nversion: 1.0.0\n',
  );
});
afterEach(async () => {
  await rm(dir, { recursive: true, force: true });
});

describe('handleModuleChangeset', () => {
  it('writes a changeset keyed by the module id that the engine can parse', async () => {
    const res = await handleModuleChangeset([dir], { bump: 'minor', message: 'Added a view.' });
    expect(res.success).toBe(true);

    const files = (await readdir(join(dir, '.changeset'))).filter((f) => f.endsWith('.md'));
    expect(files.length).toBe(1);
    const parsed = parseChangeset(await readFile(join(dir, '.changeset', files[0]), 'utf-8'));
    expect(parsed.bumps).toEqual({ lunacycle: 'minor' });
    expect(parsed.summary).toBe('Added a view.');
  });

  it('honors an explicit --name and defaults the body', async () => {
    await handleModuleChangeset([dir], { bump: 'patch', name: 'fix-thing' });
    const parsed = parseChangeset(await readFile(join(dir, '.changeset', 'fix-thing.md'), 'utf-8'));
    expect(parsed.bumps).toEqual({ lunacycle: 'patch' });
    expect(parsed.summary.length).toBeGreaterThan(0);
  });

  it('rejects a missing or invalid bump', async () => {
    expect((await handleModuleChangeset([dir], {})).success).toBe(false);
    expect((await handleModuleChangeset([dir], { bump: 'huge' })).success).toBe(false);
  });

  it('errors when the manifest is unreadable', async () => {
    const empty = await mkdtemp(join(tmpdir(), 'celilo-cs-empty-'));
    try {
      expect((await handleModuleChangeset([empty], { bump: 'patch' })).success).toBe(false);
    } finally {
      await rm(empty, { recursive: true, force: true });
    }
  });
});