<?php

class Qs_Device
{
    /** @var string */
    protected static $_detectorName = 'MobileDetect';

    /** @var Qs_Device_Detector_AbstractDetector */
    protected static $_detector;

    /** @var string */
    protected static $_cookieNamePrefix = 'qs-device-';

    /** @var int */
    protected static $_cookieExpireInDays = 1;

    /**
     * @param null|string $userAgent
     * @return bool
     */
    public static function isMobile($userAgent = null)
    {
        $isMobile = self::_getCookie(__METHOD__);
        if (null === $isMobile) {
            if (null !== $userAgent) {
                self::setUserAgent($userAgent);
            }
            $isMobile = self::_getDetector()->isMobile();

            self::_setCookie(__METHOD__, $isMobile);
        }

        return (bool) $isMobile;
    }

    /**
     * @param null|string $userAgent
     * @return bool
     */
    public static function isTouchscreen($userAgent = null)
    {
        $isTouchscreen = self::_getCookie(__METHOD__);
        if (null === $isTouchscreen) {
            if (null !== $userAgent) {
                self::getUserAgent($userAgent);
            }
            $pointingMethod = self::_getDetector()->getPointingMethod();
            $isTouchscreen =  (Qs_Device_Detector_AbstractDetector::POINTING_METHOD_TOUCHSCREEN == $pointingMethod);

            self::_setCookie(__METHOD__, $isTouchscreen);
        }

        return (bool) $isTouchscreen;
    }

    /**
     * @param string $name
     * @return bool
     */
    public static function setDetectorName($name)
    {
        self::$_detectorName = (string) $name;
        return true;
    }

    /**
     * @return string
     */
    public static function getDetectorName()
    {
        return self::$_detectorName;
    }

    /**
     * @param string $userAgent
     * @return bool
     */
    public static function setUserAgent($userAgent)
    {
        self::_getDetector()->setUserAgent($userAgent);
        return true;
    }

    /**
     * @return null|string
     */
    protected static function getUserAgent()
    {
        self::_getDetector()->getUserAgent();
    }

    /**
     * @return mixed
     * @throws Qs_Exception
     */
    protected static function _getDetector()
    {
        if (null === self::$_detector) {
            $className = __CLASS__ . '_Detector_' . self::$_detectorName;
            if (!class_exists($className)) {
                throw new Qs_Exception('Unknown detector name: ' . self::$_detectorName);
            }
            self::$_detector = new $className;
        }

        return self::$_detector;
    }

    /**
     * @param string $name
     * @param string $value
     * @return bool
     */
    protected static function _setCookie($name, $value)
    {
        $cookieName = self::$_cookieNamePrefix . $name;
        $cookieExpire = time() + 60 * 60 * 24 * self::$_cookieExpireInDays;
        if (is_bool($value)) {
            $cookieValue = ($value) ? '1' : '0';
        } else {
            $cookieValue = (string) $value;
        }
        $_COOKIE[$cookieName] = $cookieValue;
        return setcookie($cookieName, $cookieValue, $cookieExpire);
    }

    /**
     * @param $name
     * @return mixed
     */
    protected static function _getCookie($name)
    {
        $cookieName = self::$_cookieNamePrefix . $name;
        return Qs_Array::get($_COOKIE, $cookieName);
    }
}