Javascript html editor cursor focus following mouse

Question

I use a dhtml (midas) editor as a html editor in my web application, what I want to do is get a focused cursor in this html editor follow the mouse, is there a way to do that?

Added Example: I want cursor in textarea follow the mouse so if you have a big text in your textarea and you are going over it with mouse, cursor (text cursor) should follow the mouse, like this:

"This is an ex|ample text" - if mouse is over "example" word and between x and a, text cursor (|) should be focused there but when I move mouse on for example "text" cursor | should be between letters where mouse is currently located.

Answer 1

Ok I found the solution using Ext.util.TextMetrics, first I get position of every character in editor, then I compare that to mouse cursor position and then update midas selection based on given character from charNum array

htmlEditor.getEl().on('mousemove', function(e)
{   
    var charNum = {},
        text = htmlEditor.getValue(),
        fWidth = htmlEditor.getWidth();

    var textMetrics = new Ext.util.TextMetrics(htmlEditor.getEl(), htmlEditor.getWidth());

    for(var n=0;n<text.length;n++)
    {
        var dat = text.substring(0, n)
        var width = textMetrics.getWidth(dat);
        var height = textMetrics.getHeight(dat);

        if(width > fWidth)
        {
            var mult = Math.ceil(width/fWidth)
            var width = width % fWidth;
            height = height*mult;
        }

        charNum[n] = [width, height];
    }

    //console.log("charNum: "+charNum.toSource());

    var mX = e.getX();
    var mY = e.getY();

    var cXY = htmlEditor.getEl().getXY();
    var cX = cXY[0];
    var cY = cXY[1];                    

    var x = mX-cX-20;
    var y = mY-cY;

    //console.log("fin xy: "+x+' '+y);

    var n = -1;
    var z = 0;
    for(key in charNum)
    {
        if(charNum[key][0] > x && charNum[key][1] > y) 
        {
            n = key-1;
            break;
        }
        n++;
        z++;
    }

    if(x < 0 && y < 14) n = -1; 


    if(n == (z-1) && n != -1)
    {
        n++;
    }

    var selection = htmlEditor.win.getSelection();

    range = selection.getRangeAt(0);
    range.selectNodeContents(htmlEditor.getEditorBody());
    range.collapse(true);
    for(var x=0;x<n;x++)
    {
        selection.modify("move", "forward", "character");
    }
});