<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>

<script>
var overlaps = (function () {
    function getPositions( elem ) {
        var pos, width, height;
        pos = $( elem ).position();
        width = $( elem ).width();
        height = $( elem ).height();
        return [ [ pos.left, pos.left + width ], [ pos.top, pos.top + height ] ];
    }

    function comparePositions( p1, p2 ) {
        var r1, r2;
        r1 = p1[0] < p2[0] ? p1 : p2;
        r2 = p1[0] < p2[0] ? p2 : p1;
        return r1[1] > r2[0] || r1[0] === r2[0];
    }

    return function ( a, b ) {
        var pos1 = getPositions( a ),
            pos2 = getPositions( b );
        return comparePositions( pos1[0], pos2[0] ) && comparePositions( pos1[1], pos2[1] );
    };
})();
 function set(){
$(function () {
    var area = $( '#area' )[0],
        box = $( '#box0' )[0],
        html;

    html = $( area ).children().not( box ).map( function ( i ) {
        return document.getElementById('boh').innerHTML = 'Red box + Box ' + ( i + 1 ) + ' = ' + overlaps( box, this );
    }).get().join( '' );
});
}
</script>

<style>
body {
    padding: 30px;
    color: #444;
    font-family: Arial, sans-serif;
}

h1 {
    font-size: 24px;
    margin-bottom: 20px;
}

#area {
    border: 2px solid gray;
    width: 500px;
    height: 400px;
    position: relative;
}

#area > div {
    background-color: rgba(122, 122, 122, 0.3);
    position: absolute;
    text-align: center;
    font-size: 50px;
    width: 60px;
    height: 60px;
}

#box0 {
    background-color: rgba(255, 0, 0, 0.5) !important;
    top: 150px;
    left: 150px;
}

#box1 {
    top: 260px;
    left: 50px;
}

#box2 {
    top: 110px;
    left: 160px;
}

#box3 {
    top: 200px;
    left: 200px;
}

#box4 {
    top: 50px;
    left: 400px;
}

p {
    margin: 5px 0;
}

* {
        -webkit-user-select: none;
        -moz-user-select: none;
        -ms-user-select: none;
        user-select: none;
          }

      .disabled{
  pointer-events: none;
}
</style>

<h1>Detect overlapping with JavaScript</h1>
<div id="area">
    <div id="box0" onDragStart="return false"></div>
    <div id="box2" onDragStart="return false"></div>
</div>

<button id="down_btn" onclick="myMove4()">Down</button>
<button id="up_btn" onclick="myMove()">Up</button>
<div id="boh"></div>

<script>
var down = false;
var pos = 0;

window.addEventListener('mouseup', function(event){
  down = false;
});
window.addEventListener('mousedown', function(event){
  down = true;
})

function myMove4() {
  setTimeout(() => {
      var elem = document.getElementById("box2");
  var id = setInterval(frame, 10);
  function frame() {
    if (pos == 350 || !down) {
      clearInterval(id);
    } else {
      pos++;
      elem.style.top = pos + 'px';
      }
    }
  }, 500);
}

function myMove() {
  setTimeout(() => {
      var elem = document.getElementById("box2");
  var id = setInterval(frame, 10);
  function frame() {
    if (pos == 350 || !down) {
      clearInterval(id);
    } else {
      pos--;
      elem.style.top = pos + 'px';
      }
    }
  }, 500);
}


setInterval(() => {

    set();

       if(document.getElementById('boh').textContent == "Red box + Box 1 = true"){
        $("#down_btn").addClass("disabled");
       }
       else{
        $("#down_btn").removeClass("disabled");
       }
    }, 100);
    setInterval(() => {

        set();

        if(document.getElementById('boh').textContent == "Red box + Box 1 = true"){
        $("#down_btn").addClass("disabled");
       }
       else{
        $("#down_btn").removeClass("disabled");
       }
    }, 200);
</script>