import { rm, writeFile, readFile, mkdtemp } from 'node:fs/promises';
import { join } from 'node:path';
import { tmpdir } from 'node:os';

import { tap, expect } from '@git.zone/tstest/tapbundle';

import {
  appendPendingChangelogEntry,
  movePendingToVersion,
  readPendingChangelog,
} from './ts/helpers.changelog.js';

const withChangelogFile = async (
  initialContent: string,
  testFunction: (filePath: string) => Promise<void>,
) => {
  const testDir = await mkdtemp(join(tmpdir(), 'gitzone-changelog-'));
  const changelogPath = join(testDir, 'changelog.md');
  try {
    await writeFile(changelogPath, initialContent);
    await testFunction(changelogPath);
  } finally {
    await rm(testDir, { recursive: true, force: true });
  }
};

tap.test('readPendingChangelog should not create a missing Pending section', async () => {
  await withChangelogFile('# Changelog\n\n## 2026-01-01 - 1.0.0\n\n### Fixes\n\n- existing\n', async (filePath) => {
    const pending = await readPendingChangelog(filePath, 'Pending');
    const changelogContent = await readFile(filePath, 'utf8');

    expect(pending.isEmpty).toBeTrue();
    expect(pending.block).toEqual('');
    expect(changelogContent).not.toInclude('## Pending');
  });
});

tap.test('movePendingToVersion should fail when Pending is missing', async () => {
  await withChangelogFile('# Changelog\n\n## 2026-01-01 - 1.0.0\n\n### Fixes\n\n- existing\n', async (filePath) => {
    let errorMessage = '';
    try {
      await movePendingToVersion(filePath, 'Pending', '## {{date}} - {{version}}', '1.0.1', '2026-01-02');
    } catch (error) {
      errorMessage = error instanceof Error ? error.message : String(error);
    }

    expect(errorMessage).toEqual('No pending changelog entries. Nothing to release.');

    const changelogContent = await readFile(filePath, 'utf8');
    expect(changelogContent).not.toInclude('## Pending');
  });
});

tap.test('movePendingToVersion should remove the consumed Pending section', async () => {
  await withChangelogFile('# Changelog\n\n## Pending\n\n### Fixes\n\n- pending fix\n\n## 2026-01-01 - 1.0.0\n\n### Fixes\n\n- existing\n', async (filePath) => {
    await movePendingToVersion(filePath, 'Pending', '## {{date}} - {{version}}', '1.0.1', '2026-01-02');

    const changelogContent = await readFile(filePath, 'utf8');
    expect(changelogContent).not.toInclude('## Pending');
    expect(changelogContent).toInclude('## 2026-01-02 - 1.0.1\n\n### Fixes\n\n- pending fix');
    expect(changelogContent).toInclude('## 2026-01-01 - 1.0.0\n\n### Fixes\n\n- existing');
  });
});

tap.test('appendPendingChangelogEntry should recreate Pending when needed', async () => {
  await withChangelogFile('# Changelog\n\n## 2026-01-01 - 1.0.0\n\n### Fixes\n\n- existing\n', async (filePath) => {
    await appendPendingChangelogEntry(filePath, 'Pending', {
      type: 'fix',
      scope: 'changelog',
      message: 'record pending changes',
    });

    const changelogContent = await readFile(filePath, 'utf8');
    expect(changelogContent).toInclude('## Pending\n\n### Fixes\n\n- record pending changes (changelog)');
    expect(changelogContent).toInclude('## 2026-01-01 - 1.0.0');
  });
});

export default tap.start();