<?php
namespace Home\Common;

class Wechat {
	/**
	 * 调试模式，将错误通过文本消息回复显示
	 *
	 * @var boolean
	 */
	private $debug;
	/**
	 * 以数组的形式保存微信服务器每次发来的请求
	 *
	 * @var array
	 */
	private $request;
	/**
	 * 初始化，判断此次请求是否为验证请求，并以数组形式保存
	 *
	 * @param string $token 验证信息
	 * @param boolean $debug 调试模式，默认为关闭
	 */
	public function __construct($token, $debug = FALSE) {
		if ($this -> isValid() && $this -> validateSignature($token)) {
			exit($_GET['echostr']);
		}
		$this -> debug = $debug;
		set_error_handler(array(&$this, 'errorHandler'));
		// 设置错误处理函数，将错误通过文本消息回复显示
		$xml = (array) simplexml_load_string($GLOBALS['HTTP_RAW_POST_DATA'], 'SimpleXMLElement', LIBXML_NOCDATA);
		$this -> request = array_change_key_case($xml, CASE_LOWER);
		// 将数组键名转换为小写，提高健壮性，减少因大小写不同而出现的问题
	}
	/**
	 * 判断此次请求是否为验证请求
	 *
	 * @return boolean
	 */
	private function isValid() {
		return isset($_GET['echostr']);
	}
	/**
	 * 判断验证请求的签名信息是否正确
	 *
	 * @param  string $token 验证信息
	 * @return boolean
	 */
	private function validateSignature($token) {
		$signature = $_GET['signature'];
		$timestamp = $_GET['timestamp'];
		$nonce = $_GET['nonce'];
		$signatureArray = array($token, $timestamp, $nonce);
		sort($signatureArray);

		return sha1(implode($signatureArray)) == $signature;
	}

	/**
	 * 获取本次请求中的参数，不区分大小
	 *
	 * @param  string $param 参数名，默认为无参
	 * @return mixed
	 */
	protected function getRequest($param = FALSE) {
		if ($param === FALSE) {
			return $this -> request;
		}

		$param = strtolower($param);

		if (isset($this -> request[$param])) {
			return $this -> request[$param];
		}

		return NULL;
	}

	/**
	 * 用户关注时触发，用于子类重写
	 *
	 * @return void
	 */
	protected function onSubscribe() {
	}

/**
	 * 用户Event时时触发，用于子类重写
	 *
	 * @return void
	 */
	protected function onClickEvent(){
	}
	/**
	 * 用户取消关注时触发，用于子类重写
	 *
	 * @return void
	 */
	protected function onUnsubscribe() {
	}

	/**
	 * 收到文本消息时触发，用于子类重写
	 *
	 * @return void
	 */
	protected function onText() {
	}

	/**
	 * 收到图片消息时触发，用于子类重写
	 *
	 * @return void
	 */
	protected function onImage() {
	}

	/**
	 * 收到地理位置消息时触发，用于子类重写
	 *
	 * @return void
	 */
	protected function onLocation() {
	}

	/**
	 * 收到链接消息时触发，用于子类重写
	 *
	 * @return void
	 */
	protected function onLink() {
	}

	/**
	 * 收到未知类型消息时触发，用于子类重写
	 *
	 * @return void
	 */
	protected function onUnknown() {
	}

	/**
	 * 回复文本消息
	 *
	 * @param  string  $content  消息内容
	 * @param  integer $funcFlag 默认为0，设为1时星标刚才收到的消息
	 * @return void
	 */
	protected function responseText($content, $funcFlag = 0) {
		exit(new TextResponse($this -> getRequest('fromusername'), $this -> getRequest('tousername'), $content, $funcFlag));
	}

	/**
	 * 回复音乐消息
	 *
	 * @param  string  $title       音乐标题
	 * @param  string  $description 音乐描述
	 * @param  string  $musicUrl    音乐链接
	 * @param  string  $hqMusicUrl  高质量音乐链接，Wi-Fi 环境下优先使用
	 * @param  integer $funcFlag    默认为0，设为1时星标刚才收到的消息
	 * @return void
	 */
	protected function responseMusic($title, $description, $musicUrl, $hqMusicUrl, $funcFlag = 0) {
		exit(new MusicResponse($this -> getRequest('fromusername'), $this -> getRequest('tousername'), $title, $description, $musicUrl, $hqMusicUrl, $funcFlag));
	}

	/**
	 * 回复图文消息
	 * @param  array   $items    由单条图文消息类型 NewsResponseItem() 组成的数组
	 * @param  integer $funcFlag 默认为0，设为1时星标刚才收到的消息
	 * @return void
	 */
	protected function responseNews($items, $funcFlag = 0) {
		exit(new NewsResponse($this -> getRequest('fromusername'), $this -> getRequest('tousername'), $items, $funcFlag));
	}
    

	/**
	 * 分析消息类型，并分发给对应的函数
	 *
	 * @return void
	 */

	public function run() {
		switch ($this->getRequest('msgtype')) {

			case 'event' :
				switch ($this->getRequest('event')) {

					case 'subscribe' :
						$this -> onSubscribe();
						break;

					case 'unsubscribe' :
						$this -> onUnsubscribe();
						break;
					case 'CLICK' :
						$this -> onClickEvent('halo_hot');
						break;
					default:
						$this -> onText();
						break;
				}

				break;

			case 'text' :
				$this -> onText();
				break;

			case 'image' :
				$this -> onImage();
				break;

			case 'location' :
				$this -> onLocation();
				break;

			case 'link' :
				$this -> onLink();
				break;

			default :
				$this -> onUnknown();
				break;
		}
	}

	/**
	 * 自定义的错误处理函数，将 PHP 错误通过文本消息回复显示
	 * @param  int $level   错误代码
	 * @param  string $msg  错误内容
	 * @param  string $file 产生错误的文件
	 * @param  int $line    产生错误的行数
	 * @return void
	 */
	protected function errorHandler($level, $msg, $file, $line) {
		if (!$this -> debug) {
			return;
		}

		$error_type = array(
		// E_ERROR             => 'Error',
		E_WARNING => 'Warning',
		// E_PARSE             => 'Parse Error',
		E_NOTICE => 'Notice',
		// E_CORE_ERROR        => 'Core Error',
		// E_CORE_WARNING      => 'Core Warning',
		// E_COMPILE_ERROR     => 'Compile Error',
		// E_COMPILE_WARNING   => 'Compile Warning',
		E_USER_ERROR => 'User Error', E_USER_WARNING => 'User Warning', E_USER_NOTICE => 'User Notice', E_STRICT => 'Strict', E_RECOVERABLE_ERROR => 'Recoverable Error', E_DEPRECATED => 'Deprecated', E_USER_DEPRECATED => 'User Deprecated', );

		$template = <<<ERR
PHP 报错啦！

%s: %s
File: %s
Line: %s
ERR;

		$this -> responseText(sprintf($template, $error_type[$level], $msg, $file, $line));
	}

}

/**
 * 用于回复的基本消息类型
 */
abstract class WechatResponse {

	protected $toUserName;
	protected $fromUserName;
	protected $funcFlag;

	public function __construct($toUserName, $fromUserName, $funcFlag) {
		$this -> toUserName = $toUserName;
		$this -> fromUserName = $fromUserName;
		$this -> funcFlag = $funcFlag;
	}

	abstract public function __toString();

}

/**
 * 用于回复的文本消息类型
 */
class TextResponse extends WechatResponse {

	protected $content;

	protected $template = <<<XML
<xml>
  <ToUserName><![CDATA[%s]]></ToUserName>
  <FromUserName><![CDATA[%s]]></FromUserName>
  <CreateTime>%s</CreateTime>
  <MsgType><![CDATA[text]]></MsgType>
  <Content><![CDATA[%s]]></Content>
  <FuncFlag>%s<FuncFlag>
</xml>
XML;

	public function __construct($toUserName, $fromUserName, $content, $funcFlag = 0) {
		parent::__construct($toUserName, $fromUserName, $funcFlag);
		$this -> content = $content;
	}

	public function __toString() {
		return sprintf($this -> template, $this -> toUserName, $this -> fromUserName, time(), $this -> content, $this -> funcFlag);
	}

}

/**
 * 用于回复的音乐消息类型
 */
class MusicResponse extends WechatResponse {

	protected $title;
	protected $description;
	protected $musicUrl;
	protected $hqMusicUrl;

	protected $template = <<<XML
<xml>
  <ToUserName><![CDATA[%s]]></ToUserName>
  <FromUserName><![CDATA[%s]]></FromUserName>
  <CreateTime>%s</CreateTime>
  <MsgType><![CDATA[music]]></MsgType>
  <Music>
    <Title><![CDATA[%s]]></Title>
    <Description><![CDATA[%s]]></Description>
    <MusicUrl><![CDATA[%s]]></MusicUrl>
    <HQMusicUrl><![CDATA[%s]]></HQMusicUrl>
  </Music>
  <FuncFlag>%s<FuncFlag>
</xml>
XML;

	public function __construct($toUserName, $fromUserName, $title, $description, $musicUrl, $hqMusicUrl, $funcFlag) {
		parent::__construct($toUserName, $fromUserName, $funcFlag);
		$this -> title = $title;
		$this -> description = $description;
		$this -> musicUrl = $musicUrl;
		$this -> hqMusicUrl = $hqMusicUrl;
	}

	public function __toString() {
		return sprintf($this -> template, $this -> toUserName, $this -> fromUserName, time(), $this -> title, $this -> description, $this -> musicUrl, $this -> hqMusicUrl, $this -> funcFlag);
	}

}

/**
 * 用于回复的图文消息类型
 */
class NewsResponse extends WechatResponse {

	protected $items = array();

	protected $template = <<<XML
<xml>
  <ToUserName><![CDATA[%s]]></ToUserName>
  <FromUserName><![CDATA[%s]]></FromUserName>
  <CreateTime>%s</CreateTime>
  <MsgType><![CDATA[news]]></MsgType>
  <ArticleCount>%s</ArticleCount>
  <Articles>
    %s
  </Articles>
  <FuncFlag>%s<FuncFlag>
</xml>'
XML;

	public function __construct($toUserName, $fromUserName, $items, $funcFlag) {
		parent::__construct($toUserName, $fromUserName, $funcFlag);
		$this -> items = $items;
	}

	public function __toString() {
		return sprintf($this -> template, $this -> toUserName, $this -> fromUserName, time(), count($this -> items), implode($this -> items), $this -> funcFlag);
	}

}

/**
 * 单条图文消息类型
 */
class NewsResponseItem {

	protected $title;
	protected $description;
	protected $picUrl;
	protected $url;

	protected $template = <<<XML
<item>
  <Title><![CDATA[%s]]></Title>
  <Description><![CDATA[%s]]></Description>
  <PicUrl><![CDATA[%s]]></PicUrl>
  <Url><![CDATA[%s]]></Url>
</item>
XML;

	public function __construct($title, $description, $picUrl, $url) {
		$this -> title = $title;
		$this -> description = $description;
		$this -> picUrl = $picUrl;
		$this -> url = $url;
	}

	public function __toString() {
		return sprintf($this -> template, $this -> title, $this -> description, $this -> picUrl, $this -> url);
	}

}