<?php
/*
    方倍工作室
    http://www.cnblogs.com/txw1958/
    CopyRight 2014 All Rights Reserved
*/

define("TOKEN", "weixin");

$wechatObj = new wechatCallbackapiTest();
if (!isset($_GET['echostr'])) {
    $wechatObj->responseMsg();
}else{
    $wechatObj->valid();
}

class wechatCallbackapiTest
{
    //验证签名
    public function valid()
    {
        $echoStr = $_GET["echostr"];
        $signature = $_GET["signature"];
        $timestamp = $_GET["timestamp"];
        $nonce = $_GET["nonce"];
        $token = TOKEN;
        $tmpArr = array($token, $timestamp, $nonce);
        sort($tmpArr);
        $tmpStr = implode($tmpArr);
        $tmpStr = sha1($tmpStr);
        if($tmpStr == $signature){
            echo $echoStr;
            exit;
        }
    }

    //响应消息
    public function responseMsg()
    {
        $postStr = $GLOBALS["HTTP_RAW_POST_DATA"];
        if (!empty($postStr)){
            $postObj = simplexml_load_string($postStr, 'SimpleXMLElement', LIBXML_NOCDATA);
            $RX_TYPE = trim($postObj->MsgType);
             
            //消息类型分离
            switch ($RX_TYPE)
            {
                case "event":
                    $result = $this->receiveEvent($postObj);
                    break;
                case "text":
                    $result = $this->receiveText($postObj);
                    break;
            }
            echo $result;
        }else {
            echo "";
            exit;
        }
    }

    //接收事件消息
    private function receiveEvent($object)
    {
        $content = "";
        switch ($object->Event)
        {
            case "subscribe":
                $content = "欢迎关注方倍工作室\n回复 2048 开始游戏";
                break;
        }
        if(is_array($content)){
            if (isset($content[0])){
                $result = $this->transmitNews($object, $content);
            }else if (isset($content['MusicUrl'])){
                $result = $this->transmitMusic($object, $content);
            }
        }else{
            $result = $this->transmitText($object, $content);
        }

        return $result;
    }

    //接收文本消息
    private function receiveText($object)
    {
        $keyword = trim($object->Content);
        
        if (strstr($keyword, "2048")){
            $content = array();
            $content[] = array("Title"=>"2048游戏",  "Description"=>"游戏规则很简单，每次可以选择上下左右其中一个方向去滑动，每滑动一次，所有的数字方块都会往滑动的方向靠拢外，系统也会在空白的地方乱数出现一个数字方块，相同数字的方块在靠拢、相撞时会相加。系统给予的数字方块不是2就是4，玩家要想办法在这小小的16格范围中凑出“2048”这个数字方块。", "PicUrl"=>"http://img.laohu.com/www/201403/27/1395908994962.png", "Url" =>"http://gabrielecirulli.github.io/2048/");
        }else{
            $content = date("Y-m-d H:i:s",time())."\n技术支持 方倍工作室";
        }
        
        if(is_array($content)){
            if (isset($content[0]['PicUrl'])){
                $result = $this->transmitNews($object, $content);
            }else if (isset($content['MusicUrl'])){
                $result = $this->transmitMusic($object, $content);
            }
        }else{
            $result = $this->transmitText($object, $content);
        }
    }

    //回复文本消息
    private function transmitText($object, $content)
    {
        $xmlTpl = "<xml>
<ToUserName><![CDATA[%s]]></ToUserName>
<FromUserName><![CDATA[%s]]></FromUserName>
<CreateTime>%s</CreateTime>
<MsgType><![CDATA[text]]></MsgType>
<Content><![CDATA[%s]]></Content>
</xml>";
        $result = sprintf($xmlTpl, $object->FromUserName, $object->ToUserName, time(), $content);
        return $result;
    }

    //回复图文消息
    private function transmitNews($object, $newsArray)
    {
        if(!is_array($newsArray)){
            return;
        }
        $itemTpl = "    <item>
        <Title><![CDATA[%s]]></Title>
        <Description><![CDATA[%s]]></Description>
        <PicUrl><![CDATA[%s]]></PicUrl>
        <Url><![CDATA[%s]]></Url>
    </item>
";
        $item_str = "";
        foreach ($newsArray as $item){
            $item_str .= sprintf($itemTpl, $item['Title'], $item['Description'], $item['PicUrl'], $item['Url']);
        }
        $xmlTpl = "<xml>
<ToUserName><![CDATA[%s]]></ToUserName>
<FromUserName><![CDATA[%s]]></FromUserName>
<CreateTime>%s</CreateTime>
<MsgType><![CDATA[news]]></MsgType>
<ArticleCount>%s</ArticleCount>
<Articles>
$item_str</Articles>
</xml>";

        $result = sprintf($xmlTpl, $object->FromUserName, $object->ToUserName, time(), count($newsArray));
        return $result;
    }
}
?>