/* Real incremental website WebSocket; never resubmit a question automatically. */
(function(root){
 function request(url,payload,onSnapshot){
  return new Promise((resolve,reject)=>{
   const target=new URL(url+'/stream',location.href);
   if(target.origin!==location.origin){reject(new Error('对话地址无效'));return}
   target.protocol=target.protocol==='https:'?'wss:':'ws:';
   let socket,settled=false,ready=false,sent=false;
   const timer=setTimeout(()=>finish(new Error('回复连接超时，尚未确认完整回答；请重试原问题。')),125000);
   const leave=()=>finish(new Error('连接已断开，可重试原问题查询同一次请求。'));
   const invalid=()=>new Error('回复连接中断，尚未确认完整回答；请重试原问题。');
   function finish(error,data){
    if(settled)return;settled=true;clearTimeout(timer);root.removeEventListener('pagehide',leave);
    if(socket&&(socket.readyState===WebSocket.OPEN||socket.readyState===WebSocket.CONNECTING))socket.close();
    if(error)reject(error);else resolve(data);
   }
   root.addEventListener('pagehide',leave,{once:true});
   try{socket=new WebSocket(target.href)}catch{finish(invalid());return}
   socket.addEventListener('open',()=>{
    if(settled||sent)return;
    sent=true;socket.send(JSON.stringify(payload));
   });
   socket.addEventListener('message',event=>{
    if(settled)return;
    try{
     if(typeof event.data!=='string'||event.data.length>262144)throw invalid();
     const frame=JSON.parse(event.data),data=frame.data;
     if(frame.event==='ready'){
      if(data?.v!==1||ready)throw invalid();ready=true;
     }else if(frame.event==='ping'){
      if(!ready)throw invalid();
     }else if(frame.event==='snapshot'){
      if(!ready||typeof data?.text!=='string'||data.text.length>65536)throw invalid();
      onSnapshot(data.text);
     }else if(frame.event==='completed'){
      if(!ready||typeof data?.answer!=='string'||typeof data.mode!=='string')throw invalid();
      finish(null,data);
     }else throw invalid();
    }catch{finish(invalid())}
   });
   socket.addEventListener('error',()=>finish(invalid()));
   socket.addEventListener('close',()=>{if(!settled)finish(invalid())});
  });
 }
 root.ZhiweiChatStream={request};
})(window);