class MockFileSessionStorage

class MockFileSessionStorage extends MockArraySessionStorage {
    private string $savePath;
    
    /**
     * @param string|null $savePath Path of directory to save session files
     */
    public function __construct(?string $savePath = null, string $name = 'MOCKSESSID', ?MetadataBag $metaBag = null) {
        $savePath ??= sys_get_temp_dir();
        if (!is_dir($savePath) && !@mkdir($savePath, 0777, true) && !is_dir($savePath)) {
            throw new \RuntimeException(\sprintf('Session Storage was not able to create directory "%s".', $savePath));
        }
        $this->savePath = $savePath;
        parent::__construct($name, $metaBag);
    }
    public function start() : bool {
        if ($this->started) {
            return true;
        }
        if (!$this->id) {
            $this->id = $this->generateId();
        }
        $this->read();
        $this->started = true;
        return true;
    }
    public function regenerate(bool $destroy = false, ?int $lifetime = null) : bool {
        if (!$this->started) {
            $this->start();
        }
        if ($destroy) {
            $this->destroy();
        }
        return parent::regenerate($destroy, $lifetime);
    }
    public function save() : void {
        if (!$this->started) {
            throw new \RuntimeException('Trying to save a session that was not started yet or was already closed.');
        }
        $data = $this->data;
        foreach ($this->bags as $bag) {
            if (empty($data[$key = $bag->getStorageKey()])) {
                unset($data[$key]);
            }
        }
        if ([
            $key = $this->metadataBag
                ->getStorageKey(),
        ] === array_keys($data)) {
            unset($data[$key]);
        }
        try {
            if ($data) {
                $path = $this->getFilePath();
                $tmp = $path . bin2hex(random_bytes(6));
                file_put_contents($tmp, serialize($data));
                rename($tmp, $path);
            }
            else {
                $this->destroy();
            }
        } finally {
            $this->data = $data;
        }
        // this is needed when the session object is re-used across multiple requests
        // in functional tests.
        $this->started = false;
    }
    
    /**
     * Deletes a session from persistent storage.
     * Deliberately leaves session data in memory intact.
     */
    private function destroy() : void {
        set_error_handler(static function () {
        });
        try {
            unlink($this->getFilePath());
        } finally {
            restore_error_handler();
        }
    }
    
    /**
     * Calculate path to file.
     */
    private function getFilePath() : string {
        return $this->savePath . '/' . $this->id . '.mocksess';
    }
    
    /**
     * Reads session from storage and loads session.
     */
    private function read() : void {
        set_error_handler(static function () {
        });
        try {
            $data = file_get_contents($this->getFilePath());
        } finally {
            restore_error_handler();
        }
        $this->data = $data ? unserialize($data) : [];
        $this->loadSession();
    }

}