<?php
declare(strict_types=1);

final class Settings
{
    /** @var array<string,string> */
    private array $values;

    private function __construct(array $values)
    {
        $this->values = $values;
    }

    public static function load(string $path): self
    {
        $values = [];
        if (is_readable($path)) {
            $lines = file($path, FILE_IGNORE_NEW_LINES);
            if ($lines !== false) {
                foreach ($lines as $line) {
                    $line = trim($line);
                    if ($line === '' || $line[0] === '#') {
                        continue;
                    }

                    if (!preg_match('/^([A-Za-z0-9_]+)=(.*)$/', $line, $m)) {
                        continue;
                    }

                    $values[$m[1]] = self::parseShValue((string)$m[2]);
                }
            }
        }

        return new self($values);
    }

    /**
     * @return array{host:string,port:int,database:string,user:string,password:string,socket:string}
     */
    public static function loadMysqlCredentials(string $path): array
    {
        if (!is_readable($path)) {
            throw new RuntimeException('Brak pliku z danymi MySQL: ' . $path);
        }

        $lines = file($path, FILE_IGNORE_NEW_LINES);
        if ($lines === false) {
            throw new RuntimeException('Nie można odczytać pliku: ' . $path);
        }

        $kv = [];
        foreach ($lines as $line) {
            $line = trim($line);
            if ($line === '' || $line[0] === '#') {
                continue;
            }

            if (strpos($line, '=') !== false) {
                [$k, $v] = array_map('trim', explode('=', $line, 2));
                if ($k !== '') {
                    $kv[strtoupper($k)] = self::parseShValue($v);
                }
                continue;
            }

            $parts = explode(':', $line);
            if (count($parts) >= 5) {
                return [
                    'host' => trim($parts[0]) !== '' ? trim($parts[0]) : 'localhost',
                    'port' => (int)(trim($parts[1]) !== '' ? trim($parts[1]) : '3306'),
                    'database' => trim($parts[2]) !== '' ? trim($parts[2]) : 'mysql',
                    'user' => trim($parts[3]) !== '' ? trim($parts[3]) : 'root',
                    'password' => trim(implode(':', array_slice($parts, 4))),
                    'socket' => '',
                ];
            }
        }

        $host = trim((string)($kv['HOST'] ?? $kv['MYSQL_HOST'] ?? ''));
        if ($host === '') {
            $host = 'localhost';
        }

        $portRaw = trim((string)($kv['PORT'] ?? $kv['MYSQL_PORT'] ?? '3306'));
        $port = preg_match('/^[0-9]+$/', $portRaw) ? (int)$portRaw : 3306;
        if ($port < 1 || $port > 65535) {
            $port = 3306;
        }

        $database = trim((string)($kv['DATABASE'] ?? $kv['MYSQL_DATABASE'] ?? $kv['DB'] ?? 'mysql'));
        if ($database === '' || $database === '*') {
            $database = 'mysql';
        }

        $user = trim((string)($kv['USER'] ?? $kv['MYSQL_USER'] ?? 'root'));
        $password = trim((string)($kv['PASSWORD'] ?? $kv['PASSWD'] ?? $kv['MYSQL_PASSWORD'] ?? ''));
        $socket = trim((string)($kv['SOCKET'] ?? $kv['MYSQL_SOCKET'] ?? ''));

        if ($user === '') {
            throw new RuntimeException('Brak użytkownika MySQL w pliku: ' . $path);
        }

        return [
            'host' => $host,
            'port' => $port,
            'database' => $database,
            'user' => $user,
            'password' => $password,
            'socket' => $socket,
        ];
    }

    public function mysqlCredentialsFile(): string
    {
        $path = trim($this->getString('MYSQL_PLUGIN_CREDENTIALS_FILE', '/usr/local/directadmin/conf/alt-mysql.conf'));
        return $path !== '' ? $path : '/usr/local/directadmin/conf/alt-mysql.conf';
    }

    public function mysqlClientBinDir(): string
    {
        return rtrim(trim($this->getString('MYSQL_PLUGIN_CLIENT_BIN_DIR', '')), '/');
    }

    public function getString(string $key, string $default = ''): string
    {
        return isset($this->values[$key]) ? trim($this->values[$key]) : $default;
    }

    public function getInt(string $key, int $default = 0): int
    {
        if (!isset($this->values[$key])) {
            return $default;
        }

        $value = trim($this->values[$key]);
        if ($value === '' || !preg_match('/^-?[0-9]+$/', $value)) {
            return $default;
        }

        return (int)$value;
    }

    public function getBool(string $key, bool $default = false): bool
    {
        if (!isset($this->values[$key])) {
            return $default;
        }

        return self::toBool($this->values[$key], $default);
    }

    public function defaultDatabasesLimit(): int
    {
        $limit = $this->getInt('MYSQL_PLUGIN_DEFAULT_DB_LIMIT', 5);
        return $limit < 0 ? 0 : $limit;
    }

    public function alwaysEnabled(): bool
    {
        return $this->getBool('always_enabled', true);
    }

    public function maxHostsPerUser(): int
    {
        $limit = $this->getInt('MYSQL_PLUGIN_MAX_HOSTS_PER_USER', 30);
        return $limit < 1 ? 1 : $limit;
    }

    public function allowRemoteHosts(): bool
    {
        if (array_key_exists('allow_remote_hosts', $this->values)) {
            return self::toBool($this->values['allow_remote_hosts'], false);
        }

        if (array_key_exists('MYSQL_PLUGIN_ALLOW_REMOTE_HOSTS', $this->values)) {
            return self::toBool($this->values['MYSQL_PLUGIN_ALLOW_REMOTE_HOSTS'], false);
        }

        return false;
    }

    public function modifyServerConfiguration(): bool
    {
        if ($this->allowRemoteHosts()) {
            return true;
        }

        if (array_key_exists('modify_server_configuration', $this->values)) {
            return self::toBool($this->values['modify_server_configuration'], false);
        }

        if (array_key_exists('MYSQL_PLUGIN_MODIFY_SERVER_CONFIGURATION', $this->values)) {
            return self::toBool($this->values['MYSQL_PLUGIN_MODIFY_SERVER_CONFIGURATION'], false);
        }

        return false;
    }

    public function hostSyncScript(): string
    {
        $default = '/usr/local/directadmin/plugins/alt-mysql/scripts/setup/mysql_host_sync.sh';
        $path = $this->getString('MYSQL_PLUGIN_SUDO_SYNC_HOSTS', $default);
        return $path !== '' ? $path : $default;
    }

    public function enableBackup(): bool
    {
        return $this->getBool('ENABLE_BACKUP', true);
    }

    public function enableUploadBackup(): bool
    {
        return $this->getBool('ENABLE_UPLOAD_BACKUP', true);
    }

    public function enableAdminer(): bool
    {
        if (!$this->getBool('ENABLE_PHPMYADMIN', $this->getBool('ENABLE_ADMINER', true))) {
            return false;
        }

        return $this->isPhpMyAdminInstalled();
    }

    public function phpMyAdminInstallDir(): string
    {
        $path = trim($this->getString('PHPMYADMIN_INSTALL_DIR', '/var/www/html/alt-mysql-phpmyadmin'));
        return $path !== '' ? rtrim($path, '/') : '/var/www/html/alt-mysql-phpmyadmin';
    }

    public function adminerUrlPath(): string
    {
        $path = trim($this->getString('PHPMYADMIN_URL_PATH', $this->getString('ADMINER_URL_PATH', '/alt-mysql-phpmyadmin')));
        if ($path === '') {
            return '/alt-mysql-phpmyadmin';
        }

        if ($path[0] !== '/') {
            $path = '/' . $path;
        }

        $path = rtrim($path, '/');
        return $path !== '' ? $path : '/alt-mysql-phpmyadmin';
    }

    public function adminerPublicBaseUrl(): string
    {
        $url = trim($this->getString('PHPMYADMIN_PUBLIC_BASE_URL', $this->getString('ADMINER_PUBLIC_BASE_URL', '')));
        if ($url === '') {
            return '';
        }

        $url = rtrim($url, '/');
        if (!preg_match('#^https?://#i', $url)) {
            return '';
        }

        return $url;
    }

    public function adminerPublic(): bool
    {
        return $this->getBool('PHPMYADMIN_PUBLIC', $this->getBool('ADMINER_PUBLIC', false));
    }

    public function adminerSsoDir(): string
    {
        $path = trim($this->getString('PHPMYADMIN_SSO_DIR', $this->getString('ADMINER_SSO_DIR', $this->phpMyAdminInstallDir() . '/runtime')));
        if ($path === '') {
            $path = $this->phpMyAdminInstallDir() . '/runtime';
        }
        return rtrim($path, '/');
    }

    public function adminerTicketTtl(): int
    {
        $ttl = $this->getInt('PHPMYADMIN_TICKET_TTL', $this->getInt('ADMINER_TICKET_TTL', 120));
        if ($ttl < 10) {
            return 10;
        }
        if ($ttl > 300) {
            return 300;
        }
        return $ttl;
    }

    public function adminerSessionTtl(): int
    {
        $ttl = $this->getInt('PHPMYADMIN_SESSION_TTL', $this->getInt('ADMINER_SESSION_TTL', 900));
        if ($ttl < 60) {
            return 60;
        }
        if ($ttl > 3600) {
            return 3600;
        }
        return $ttl;
    }

    public function adminerRoleTtl(): int
    {
        $ttl = $this->getInt('PHPMYADMIN_ROLE_TTL', $this->getInt('ADMINER_ROLE_TTL', 1200));
        if ($ttl < 120) {
            return 120;
        }
        if ($ttl > 7200) {
            return 7200;
        }
        return $ttl;
    }

    public function phpMyAdminIntegrationWarning(): string
    {
        if (!$this->getBool('ENABLE_PHPMYADMIN', $this->getBool('ENABLE_ADMINER', true))) {
            return '';
        }

        $dir = $this->phpMyAdminInstallDir();
        if (!is_dir($dir)) {
            return 'Prywatna kopia phpMyAdmin dla pluginu nie jest zainstalowana. Uruchom scripts/setup/phpmyadmin_private_install.sh jako root.';
        }

        $config = $dir . '/config.inc.php';
        $signon = $dir . '/da_signon.php';
        $signonUrl = $dir . '/da_login.php';

        if (!is_readable($config)) {
            return 'Prywatny phpMyAdmin pluginu jest zainstalowany, ale nie można odczytać config.inc.php.';
        }

        if (!is_readable($signon)) {
            return 'Prywatny phpMyAdmin pluginu jest zainstalowany, ale brakuje da_signon.php. Uruchom scripts/setup/phpmyadmin_repair.sh jako root.';
        }
        if (!is_readable($signonUrl)) {
            return 'Prywatny phpMyAdmin pluginu jest zainstalowany, ale brakuje da_login.php. Uruchom scripts/setup/phpmyadmin_repair.sh jako root.';
        }

        $contents = file_get_contents($config);
        if (!is_string($contents) || strpos($contents, 'DA_MYSQL_PMA_DEFAULT_CONF') === false) {
            return 'Prywatny phpMyAdmin pluginu nie ma konfiguracji alt-mysql. Uruchom scripts/setup/phpmyadmin_repair.sh jako root.';
        }
        if (strpos($contents, "SignonURL'] = da_mysql_phpmyadmin_signon_url") === false) {
            return 'Prywatny phpMyAdmin pluginu nie ma wymaganej konfiguracji SignonURL. Uruchom scripts/setup/phpmyadmin_repair.sh jako root.';
        }
        $signonUrlContents = file_get_contents($signonUrl);
        if (!is_string($signonUrlContents) || strpos($signonUrlContents, 'da_mysql_login_consume_ticket') === false) {
            return 'Prywatny phpMyAdmin pluginu nie obsługuje jednorazowych ticketów SSO. Uruchom scripts/setup/phpmyadmin_repair.sh jako root.';
        }

        return '';
    }

    public function allowRestoreToOtherDatabase(): bool
    {
        return $this->getBool('ALLOW_RESTORE_TO_OTHER_DATABASE', true);
    }

    public function enableTableCount(): bool
    {
        return $this->getBool('ENABLE_TABLE_COUNT', true);
    }

    public function countDatabaseSize(): bool
    {
        return $this->getBool('COUNT_DATABASE_SIZE', true);
    }

    public function compressBackup(): bool
    {
        return $this->getBool('COMPRESS_BACKUP', true);
    }

    public function hitmeBackupLocation(string $daUser = ''): string
    {
        $path = $this->getString('HITME_BACKUP_LOCATION', '/home/admin/mysql_backup');
        if ($path === '') {
            $path = '/home/admin/mysql_backup';
        }

        if ($daUser !== '') {
            $path = str_replace(['DA_USER', 'da_user'], $daUser, $path);
        }

        return rtrim($path, '/');
    }

    public function userBaseBackupDir(string $daUser = ''): string
    {
        $path = $this->getString('USER_BASE_BACKUP_DIR', '/home/DA_USER/mysql_backup');
        if ($path === '') {
            $path = '/home/DA_USER/mysql_backup';
        }

        if ($daUser !== '') {
            $path = str_replace(['DA_USER', 'da_user'], $daUser, $path);
        }

        return rtrim($path, '/');
    }

    public function userBackupDateFormat(): string
    {
        $format = $this->getString('USER_BACKUP_DATE_FORMAT', 'd.m.Y-H.i');
        return $format !== '' ? $format : 'd.m.Y-H.i';
    }

    public function loadOrCreateSecret(string $path): string
    {
        if (is_readable($path)) {
            $value = trim((string)file_get_contents($path));
            if ($value !== '') {
                return $value;
            }
        }

        $secret = bin2hex(random_bytes(32));
        $dir = dirname($path);
        if (!is_dir($dir)) {
            @mkdir($dir, 0700, true);
        }

        if (@file_put_contents($path, $secret) !== false) {
            @chmod($path, 0600);
            return $secret;
        }

        return hash('sha256', __FILE__ . '|' . php_uname('n') . '|' . $path . '|alt-mysql');
    }

    public static function toBool(string $value, bool $default = false): bool
    {
        $v = strtolower(trim($value));
        if ($v === '') {
            return $default;
        }

        if (in_array($v, ['1', 'true', 'yes', 'y', 'on', 'checked'], true)) {
            return true;
        }

        if (in_array($v, ['0', 'false', 'no', 'n', 'off', 'unchecked'], true)) {
            return false;
        }

        return $default;
    }

    private function isPhpMyAdminInstalled(): bool
    {
        $dir = $this->phpMyAdminInstallDir();
        return is_dir($dir) && is_readable($dir . '/index.php') && is_readable($dir . '/config.inc.php');
    }

    private static function parseShValue(string $value): string
    {
        $value = trim($value);
        if ($value === '') {
            return '';
        }

        if ($value[0] === '\'' && substr($value, -1) === '\'') {
            return substr($value, 1, -1);
        }

        if ($value[0] === '"' && substr($value, -1) === '"') {
            return stripcslashes(substr($value, 1, -1));
        }

        $value = preg_replace('/\s+#.*$/', '', $value);
        return trim((string)$value);
    }
}