我有一个石头纸sciccors游戏，所以我把js代码下面

var r = 0;
var p = 0;
var s = 0;
var num = 0;

function random() {
  var num = Math.floor(Math.random() * 3);
  console.log(`${num}`);
}

function rockcho() {
  let r = 1;
  let p = 0;
  let s = 0;

};

function papercho() {
  let p = 1;
  let r = 0;
  let s = 0;
};

function scissorscho() {
  let s = 1;
  let p = 0;
  let r = 0;
}

function play() {
  if (r = 0, p = 0, s = 0) {
    nothing();
  };
  //this is for rock//
  if (r = 1) {
    if (num = 2) {
      win();
      let rock = 0;
    };
    if (num = 1) {
      lose();
    }
    if (num = 0) {
      draw();
    }
  }
}

function win() {
  alert("you win! :) click to play again");
};

function lose() {
  alert("you lost :( click to play again");
};

function draw() {
  alert("it was a draw! click to play again");
};

function nothing() {
  alert("please click a button to play.")
};

胜利警报和失败警报同时响起。谁来帮帮忙。
我试着重写代码，它没有工作，我不知道如何修复警报错误，它会关闭每当我按下一个按钮时，它不应该。