Onclick, add shortcode/bbcode to textarea?

Question

I spent about 2 hours in searching for javascript which will give me easy options of adding new "onclick, insert text" buttons for textarea, but unfortunatelly I couldn't find what I am looking for.

I have textarea:

<textarea name="user-submitted-content" rows="5" data-required="true" placeholder="<?php _e('Post Content', 'usp'); ?>" class="usp-textarea"></textarea>

I want javascript something like this:

    var newText = "[" + shortcode + "]" + selectedText + "[/" + shortcode + "]"; 

And than I can add buttons like:

<input type="button" value="youtube" onclick="formatText ('youtube');" /> 
<input type="button" value="text" onclick="formatText ('text');" />  

When I click button "youtube" it should add/insert: [youtube][/youtube] in textarea.

Above codes I took from one example of javascript which sorrounds selected text in textarea with tags:

<script type="text/javascript"> 
<!-- 
    function formatText (tag) { 
        var selectedText = document.selection.createRange().text; 

        if (selectedText != "") { 
            var newText = "[" + tag + "]" + selectedText + "[/" + tag + "]"; 
            document.selection.createRange().text = newText; 
        } 
    } 
//--> 
</script> 

<form name="my_form"> 
    <textarea name="my_textarea"></textarea><br /> 
    <input type="button" value="bold" onclick="formatText ('b');" /> 
    <input type="button" value="italic" onclick="formatText ('i');" /> 
    <input type="button" value="underline" onclick="formatText ('u');" /> 
</form>

With a couple of changes, I think it can be used also for this what I want. I really need this.

Answer 1

If am not wrong , you where looking for this

Sample DEMO 1

Sample DEMO 2

JS: Sample 1-

$("#btnYoutube").on('click', function () {
    var setText = "[youtube][/youtube]";
    $("#txtarea").val(setText);
});

$("#btnTxt").on('click', function () {
    var setText = "[text][/text]";
    $("#txtarea").val(setText);
});

Sample 2-

 $("input:button").on('click',function(){
    var getTxt=$(this).val();
    var setText='['+getTxt+'] ['+getTxt+']';
    $("#txtarea").val(setText)
});

Html:

<input id="btnYoutube" type="button" value="youtube" />
<input id="btnTxt" type="button" value="text" />
<br/>
<textarea id="txtarea" name="user-submitted-content" rows="5" data-required="true" class="usp-textarea"></textarea>

Answer 2

Append text in textarea:

<script type="text/javascript"> 
function formatText(tag) {
   var Field = document.getElementById('mytextarea');
   var val = Field.value;
   var selected_txt = val.substring(Field.selectionStart, Field.selectionEnd);
   var before_txt = val.substring(0, Field.selectionStart);
   var after_txt = val.substring(Field.selectionEnd, val.length);
   Field.value += '[' + tag + ']' + '[/' + tag + ']';
}
</script> 

<form name="my_form"> 
    <textarea id="mytextarea"></textarea><br /> 
    <input type="button" value="youtube" onclick="formatText ('youtube');" /> 
    <input type="button" value="dailymotion" onclick="formatText ('dailymotion');" /> 
    <input type="button" value="vimeo" onclick="formatText ('vimeo');" /> 
</form>

Replace text in textarea:

<script type="text/javascript"> 
function formatText(tag) {
   var Field = document.getElementById('mytextarea');
   var val = Field.value;
   var selected_txt = val.substring(Field.selectionStart, Field.selectionEnd);
   var before_txt = val.substring(0, Field.selectionStart);
   var after_txt = val.substring(Field.selectionEnd, val.length);
   Field.value = '[' + tag + ']' + '[/' + tag + ']';
}
</script> 

<form name="my_form"> 
    <textarea id="mytextarea"></textarea><br /> 
    <input type="button" value="youtube" onclick="formatText ('youtube');" /> 
    <input type="button" value="dailymotion" onclick="formatText ('dailymotion');" /> 
    <input type="button" value="vimeo" onclick="formatText ('vimeo');" /> 
</form>

Examples

Append: http://jsfiddle.net/aSgFa/

Replace: http://jsfiddle.net/bAQEs/

Also:

<script type="text/javascript"> 
function formatText(tag) {
   var Field = document.getElementById('user-submitted-content');
   var val = Field.value;
   var selected_txt = val.substring(Field.selectionStart, Field.selectionEnd);
   var before_txt = val.substring(0, Field.selectionStart);
   var after_txt = val.substring(Field.selectionEnd, val.length);
   Field.value += '' + tag + '';
}
</script>

<div class="buttons">
    <input type="button" value="youtube" onclick="formatText ('[video]YouTubeURL[/video]\n[description]Write your description[/description]');" />  
</div>