import assert from 'node:assert/strict';
import { execFileSync, spawnSync } from 'node:child_process';
import { mkdtempSync, rmSync, writeFileSync } from 'node:fs';
import { tmpdir } from 'node:os';
import { join } from 'node:path';
import { fileURLToPath } from 'node:url';

const directory = mkdtempSync(join(tmpdir(), 'ci-policy-'));
const script = fileURLToPath(new URL('./ci-policy.mjs', import.meta.url));
const git = (...args) => execFileSync('git', args, { cwd: directory, encoding: 'utf8' }).trim();
const check = (variables, expected = 0) => {
	const result = spawnSync(process.execPath, [script], {
		cwd: directory,
		encoding: 'utf8',
		env: {
			PATH: process.env.PATH,
			CI_PIPELINE_SOURCE: 'push',
			CI_COMMIT_SHA: git('rev-parse', 'HEAD'),
			CI_COMMIT_BRANCH: 'feature/test',
			...variables,
		},
	});
	assert.equal(result.status, expected, result.stdout + result.stderr);
};
const mr = {
	CI_PIPELINE_SOURCE: 'merge_request_event',
	CI_MERGE_REQUEST_SOURCE_BRANCH_NAME: 'feature/test',
	CI_MERGE_REQUEST_TARGET_BRANCH_NAME: 'develop',
	CI_MERGE_REQUEST_TITLE: 'feat(test): add policy checks',
};

try {
	git('init', '--initial-branch=main');
	git('config', 'user.name', 'CI policy test');
	git('config', 'user.email', 'ci-policy@example.invalid');
	git('remote', 'add', 'origin', directory);
	writeFileSync(join(directory, 'package.json'), '{"version":"1.5.0"}\n');
	git('add', 'package.json');
	git('commit', '-m', 'Legacy history is allowed');
	git('branch', 'develop');
	git('switch', '-c', 'feature/test');
	git('commit', '--allow-empty', '-m', 'feat(test)!: add checks');
	check({});
	check(mr);
	check({ ...mr, CI_MERGE_REQUEST_TITLE: 'Draft: feat: test policy' });
	check({ ...mr, CI_MERGE_REQUEST_TITLE: '(Draft) feat: test policy' });
	check({ ...mr, CI_MERGE_REQUEST_TARGET_BRANCH_NAME: 'main' }, 1);
	check({ ...mr, CI_MERGE_REQUEST_TITLE: 'Add checks' }, 1);
	check({ CI_COMMIT_TAG: 'v1.5.0' }, 1);
	check({ CI_COMMIT_SHA: '0'.repeat(40) }, 1);

	git('switch', 'develop');
	git('commit', '--allow-empty', '-m', 'fix: another change');
	git('switch', 'feature/test');
	check(mr, 1);
	git('rebase', 'develop');
	check(mr);
	const before = git('rev-parse', 'HEAD');
	git('commit', '--allow-empty', '-m', 'not conventional');
	check({ CI_COMMIT_BEFORE_SHA: before }, 1);
	check(mr, 1);
	git('commit', '--amend', '--allow-empty', '-m', 'ci: fix the commit title');
	check({ CI_COMMIT_BEFORE_SHA: before });

	git('switch', 'develop');
	git('merge', '--no-ff', 'feature/test', '-m', 'feat(test): add policy checks');
	git('switch', '-c', 'release/1.6.0');
	writeFileSync(join(directory, 'package.json'), '{"version":"1.6.0"}\n');
	git('add', 'package.json');
	git('commit', '-m', 'chore(release): prepare 1.6.0');
	check({
		...mr,
		CI_MERGE_REQUEST_SOURCE_BRANCH_NAME: 'release/1.6.0',
		CI_MERGE_REQUEST_TARGET_BRANCH_NAME: 'main',
	});
	check({ ...mr, CI_MERGE_REQUEST_SOURCE_BRANCH_NAME: 'release/1.6.0' });
	git('switch', 'main');
	git('merge', '--no-ff', 'release/1.6.0', '-m', 'chore(release): publish 1.6.0');
	check({ CI_COMMIT_TAG: 'v1.6.0' });
	check({ CI_COMMIT_TAG: 'v1.5.0' }, 1);
	check({ CI_COMMIT_TAG: 'v01.6.0' }, 1);
	check({ CI_COMMIT_TAG: 'v1.6.0-rc.1' }, 1);
	check({ ...mr, CI_MERGE_REQUEST_SOURCE_BRANCH_NAME: 'main' });

	git('switch', '-c', 'hotfix/1.6.1');
	git('commit', '--allow-empty', '-m', 'fix: production issue');
	check({
		...mr,
		CI_MERGE_REQUEST_SOURCE_BRANCH_NAME: 'hotfix/1.6.1',
		CI_MERGE_REQUEST_TARGET_BRANCH_NAME: 'main',
	});
	check({ ...mr, CI_MERGE_REQUEST_SOURCE_BRANCH_NAME: 'hotfix/1.6.1' });

	// The working branch must not pass by merging develop instead of rebasing.
	git('switch', 'feature/test');
	git('commit', '--allow-empty', '-m', 'feat: keep working');
	git('merge', '--no-ff', 'develop', '-m', 'chore: merge develop');
	check(mr, 1);

	console.log('CI policy integration checks passed.');
} finally {
	rmSync(directory, { recursive: true, force: true });
}