<?php
/**
  * wechat php test
  */

//define your token
define("TOKEN", "txtj");
$wechatObj = new wechatCallbackapiTest();
if (isset($_GET[‘echostr‘])) {
	$wechatObj->valid();
}else{
	$wechatObj->responseMsg();
}
class wechatCallbackapiTest
{
    public function valid()
    {
        $echoStr = $_GET["echostr"];

        //valid signature , option
        if($this->checkSignature()){
            echo $echoStr;
            exit;
        }
    }

    public function responseMsg()
    {
        //get post data, May be due to the different environments
        $postStr = $GLOBALS["HTTP_RAW_POST_DATA"];

        //extract post data
        if (!empty($postStr)){
                
                $postObj = simplexml_load_string($postStr, ‘SimpleXMLElement‘, LIBXML_NOCDATA);
                $RX_TYPE = trim($postObj->MsgType);

                switch($RX_TYPE)
                {
                    case "text":
                        $resultStr = $this->handleText($postObj);
                        break;
                    case "event":
                        $resultStr = $this->handleEvent($postObj);
                        break;
                    default:
                        $resultStr = "Unknow msg type: ".$RX_TYPE;
                        break;
                }
                echo $resultStr;
        }else {
            echo "";
            exit;
        }
    }

    public function handleText($postObj)
    {
        $fromUsername = $postObj->FromUserName;
        $toUsername = $postObj->ToUserName;
        $keyword = trim($postObj->Content);
        $time = time();
        $textTpl = "<xml>
                    <ToUserName><![CDATA[%s]]></ToUserName>
                    <FromUserName><![CDATA[%s]]></FromUserName>
                    <CreateTime>%s</CreateTime>
                    <MsgType><![CDATA[%s]]></MsgType>
                    <Content><![CDATA[%s]]></Content>
                    <FuncFlag>0</FuncFlag>
                    </xml>";             
        if(!empty( $keyword ))
        {
            $msgType = "text";
            $contentStr = "欢迎来到xxx!";
            $resultStr = sprintf($textTpl, $fromUsername, $toUsername, $time, $msgType, $contentStr);
            echo $resultStr;
        }else{
            echo "Input something...";
        }
    }

    public function handleEvent($object)
    {
        $contentStr = "";
        switch ($object->Event)
        {
            case "subscribe":
                $contentStr = "感谢您关注!";
                /*if(!isset($object->EventKey)){//方法开始可行的，不知道哪个版本后错误了
                    $EventKey = $object->EventKey;
                    $keys = explode("_", $EventKey);
                    $key = $keys[1];
                    $contentStr = "感谢您关注!";
                }*/
                if (isset($object->EventKey) && $object->EventKey != ‘‘){//最新扫描二维码关注并获取场景值方法
                    $EventKey = $object->EventKey;
                    $keys = explode("_", $EventKey);
                    $key = $keys[1];
                    // $contentStr = "扫描关注场景"."\n";
                    $contentStr = "场景值id ：".$key;
                }
                break;
            case "SCAN":
                $contentStr = "扫描带参数二维码事件!场景值id：".$object->EventKey;
                break;    
            default :
                $contentStr = "Unknow Event: ".$object->Event;
                break;
        }
        $resultStr = $this->responseText($object, $contentStr);
        return $resultStr;
    }
    
    public function responseText($object, $content, $flag=0)
    {
        $textTpl = "<xml>
                    <ToUserName><![CDATA[%s]]></ToUserName>
                    <FromUserName><![CDATA[%s]]></FromUserName>
                    <CreateTime>%s</CreateTime>
                    <MsgType><![CDATA[text]]></MsgType>
                    <Content><![CDATA[%s]]></Content>
                    <FuncFlag>%d</FuncFlag>
                    </xml>";
        $resultStr = sprintf($textTpl, $object->FromUserName, $object->ToUserName, time(), $content, $flag);
        return $resultStr;
    }

    private function checkSignature()
    {
        $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 ){
            return true;
        }else{
            return false;
        }
    }
}

?>