<?php

const SUBDOMAIN_REGEX = '^(?!\-)(?!..\-\-)[a-z0-9-]{4,63}(?<!\-)$';

function regListUserDomains(): array {
	if (isset($_SESSION['id']))
		return query('select', 'registry', ['username' => $_SESSION['id']], 'domain');
	return [];
}

function regCheckDomainPossession(string $domain): void {
	if (in_array($domain, regListUserDomains(), true) !== true)
		output(403, 'You don\'t own this domain on the registry.');
}

function regDeleteDomain(string $domain, string $user_id): void {
	// Delete domain from registry file
	$path = CONF['reg']['suffixes_path'] . '/' . regParseDomain($domain)['suffix'] . 'zone';
	$content = file_get_contents($path);
	if ($content === false)
		output(500, 'Failed to read current registry file.');
	$content = preg_replace('/^(?:[a-z0-9._-]+\.)?' . preg_quote($domain, '/') . '[\t ]+.+$/Dm', '', $content);
	if (file_put_contents($path, $content) === false)
		output(500, 'Failed to write new registry file.');

	try {
		DB->beginTransaction();

		$conditions = [
			'domain' => $domain,
			'username' => $user_id,
		];

		insert('registry-history', [
			'domain' => $domain,
			'creation' => query('select', 'registry', $conditions, 'creation')[0],
			'expiration' => date('Y-m'),
		]);

		query('delete', 'registry', $conditions);

		DB->commit();
	} catch (Exception $e) {
		DB->rollback();
		output(500, 'Database error.', [$e->getMessage()]);
	}
}

function regParseDomain(string $domain): array {
	$parts = explode('.', $domain, 2);
	$subdomain = $parts[0];
	$suffix = $parts[1];

	if (array_key_exists($suffix, CONF['reg']['suffixes']) !== true)
		output(403, 'This suffix doesn\'t exist.');

	return [
		'subdomain' => $subdomain,
		'suffix' => $suffix,
	];
}