var JSONMessage;
var xhrImg;

function trueImage(){
  var instream=xhrImg.responseText;
  self.postMessage(
    {'status':'normal','message':instream,'savePath':JSONMessage.savePath}
  );
  return;
};

function falseImage(){
  self.postMessage({'status':'error','message':'IMAGE FILE ACCEPT ERROR!!'});
  return false;
};

function downloadImage(){
  xhrImg=new XMLHttpRequest();
  xhrImg.addEventListener("load",trueImage,false);
  xhrImg.addEventListener("error",falseImage,false);
  xhrImg.open("GET",JSONMessage.imageUrl,false);
  xhrImg.overrideMimeType('text/plain;charset=x-user-defined');
  if(0<JSONMessage.refererUrl.length){
    xhrImg.setRequestHeader('Referer',JSONMessage.refererUrl);
  };
  if(0<JSONMessage.cookie){
    xhrImg.setRequestHeader('Cookie',JSONMessage.cookie);
  };
  xhrImg.send(null);
};

addEventListener("message",function(event){
  JSONMessage=JSON.parse(event.data);
  if(JSONMessage.imageUrl===undefined||JSONMessage.savePath===undefined){
    self.postMessage({'status':'error','message':'PARAMETA ERROR!!'});
    return false;
  }
  downloadImage();
}, false);