I'm trying to insert the image url where the point of the is to be when editing the textarea value.

function addImageURL()
{
 var imageurl = prompt("Enter image URL", "Your name")
 var post = document.getElementById("message-put").value;

 document.getElementById('message-put').value = post + '[img]' + imageurl + '[/img]';
}

This code grabs the value inside the adds the image url next to it which I don't want, I need it to insert it where the point was when editing the textarea

Thanks