<?php

const SUBDOMAIN_REGEX = '^[a-z0-9]{4,63}$';

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

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

function regDeleteDomain($domain) {
	// 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.');

	// Delete from database
	query('delete', 'registry', [
		'domain' => $domain,
		'username' => $_SESSION['id'],
	]);
}

function regParseDomain($domain) {
	$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,
	];
}