Cacher is the code snippet organizer for pro developers

/*
Copyright (c) 2009, Gideon Sireling

All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

    * Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.

    * Redistributions in binary form must reproduce the above
      copyright notice, this list of conditions and the following
      disclaimer in the documentation and/or other materials provided
      with the distribution.

    * Neither the name of Gideon Sireling nor the names of other
      contributors may be used to endorse or promote products derived
      from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

(function($) {
  $.fn.caret = function(pos) {
    var target = this[0];
    var isContentEditable = target && target.contentEditable === 'true';
    if (arguments.length == 0) {
      //get
      if (target) {
        //HTML5
        if (window.getSelection) {
          //contenteditable
          if (isContentEditable) {
            target.focus();
            var range1 = window.getSelection().getRangeAt(0),
                range2 = range1.cloneRange();
            range2.selectNodeContents(target);
            range2.setEnd(range1.endContainer, range1.endOffset);
            return range2.toString().length;
          }
          //textarea
          return target.selectionStart;
        }
        //IE<9
        if (document.selection) {
          target.focus();
          //contenteditable
          if (isContentEditable) {
              var range1 = document.selection.createRange(),
                  range2 = document.body.createTextRange();
              range2.moveToElementText(target);
              range2.setEndPoint('EndToEnd', range1);
              return range2.text.length;
          }
          //textarea
          var pos = 0,
              range = target.createTextRange(),
              range2 = document.selection.createRange().duplicate(),
              bookmark = range2.getBookmark();
          range.moveToBookmark(bookmark);
          while (range.moveStart('character', -1) !== 0) pos++;
          return pos;
        }
        // Addition for jsdom support
        if (target.selectionStart)
          return target.selectionStart;
      }
      //not supported
      return;
    }
    //set
    if (target) {
      if (pos == -1)
        pos = this[isContentEditable? 'text' : 'val']().length;
      //HTML5
      if (window.getSelection) {
        //contenteditable
        if (isContentEditable) {
          target.focus();
          window.getSelection().collapse(target.firstChild, pos);
        }
        //textarea
        else
          target.setSelectionRange(pos, pos);
      }
      //IE<9
      else if (document.body.createTextRange) {
        if (isContentEditable) {
          var range = document.body.createTextRange();
          range.moveToElementText(target);
          range.moveStart('character', pos);
          range.collapse(true);
          range.select();
        } else {
          var range = target.createTextRange();
          range.move('character', pos);
          range.select();
        }
      }
      if (!isContentEditable)
        target.focus();
    }
    return this;
  }
})(jQuery);