define(["exports"], function (exports) {
  "use strict";

  /**
   * DOM utilities
   */

  var Dom = {};

  /**
   * Returns text + text of children of given node
   * @param  {NodeElement} node
   * @return {String}
   */
  Dom.getText = function (node) {
    var s = node.textContent || node.innerText || node.innerHTML.replace(/<[^<>]+>/g, "");
    s = s.replace(/^\s+/, "").replace(/\s+$/, "");
    return s;
  };

  /**
   * Creates an html element with given collection of attributes
   * @param  {String} tag a string of the html tag to create
   * @param  {Array} an undetermined number of arrays containing the with 2
   *                    items, the attribute name and its value ['id','myId']
   * @return {Object}     created element
   */
  Dom.create = function (tag) {
    if (!tag || tag === "") {
      return;
    }

    var el = document.createElement(tag), args = arguments;

    if (args.length > 1) {
      for (var i = 0; i < args.length; i++) {
        var argtype = typeof args[i];
        if (argtype.toLowerCase() === "object" && args[i].length === 2) {
          el.setAttribute(args[i][0], args[i][1]);
        }
      }
    }
    return el;
  };

  /**
   * Returns a text node with given text
   * @param  {String} text
   * @return {Object}
   */
  Dom.text = function (text) {
    return document.createTextNode(text);
  };

  /**
   * Returns offset position of passed element
   * @param  {object} obj [description]
   * @return {object}     literal object with left and top values
   */
  Dom.position = function (obj) {
    var l = 0, t = 0;
    if (obj && obj.offsetParent) {
      do {
        l += obj.offsetLeft;
        t += obj.offsetTop;
      } while (obj == obj.offsetParent);
    }
    return { left: l, top: t };
  };

  Dom.hasClass = function (ele, cls) {
    if (!ele) {
      return false;
    }

    if (supportsClassList()) {
      return ele.classList.contains(cls);
    }
    return ele.className.match(new RegExp("(\\s|^)" + cls + "(\\s|$)"));
  };

  Dom.addClass = function (ele, cls) {
    if (!ele) {
      return;
    }

    if (supportsClassList()) {
      ele.classList.add(cls);
      return;
    }

    if (ele.className === "") {
      ele.className = cls;
    } else if (!this.hasClass(ele, cls)) {
      ele.className += " " + cls;
    }
  };

  Dom.removeClass = function (ele, cls) {
    if (!ele) {
      return;
    }

    if (supportsClassList()) {
      ele.classList.remove(cls);
      return;
    }
    var reg = new RegExp("(\\s|^)" + cls + "(\\s|$)", "g");
    ele.className = ele.className.replace(reg, "");
  };

  /**
   * Creates and returns an option element
   * @param  {String}  text  option text
   * @param  {String}  value option value
   * @param  {Boolean} isSel whether option is selected
   * @return {Object}        option element
   */
  Dom.createOpt = function (text, value, isSel) {
    var isSelected = isSel ? true : false, opt = isSelected ? this.create("option", ["value", value], ["selected", "true"]) : this.create("option", ["value", value]);
    opt.appendChild(this.text(text));
    return opt;
  };

  /**
   * Creates and returns a checklist item
   * @param  {Number} chkIndex  index of check item
   * @param  {String} chkValue  check item value
   * @param  {String} labelText check item label text
   * @return {Object}           li DOM element
   */
  Dom.createCheckItem = function (chkIndex, chkValue, labelText) {
    var li = this.create("li"), label = this.create("label", ["for", chkIndex]), check = this.create("input", ["id", chkIndex], ["name", chkIndex], ["type", "checkbox"], ["value", chkValue]);
    label.appendChild(check);
    label.appendChild(this.text(labelText));
    li.appendChild(label);
    li.label = label;
    li.check = check;
    return li;
  };

  Dom.id = function (id) {
    return document.getElementById(id);
  };

  Dom.tag = function (o, tagname) {
    return o.getElementsByTagName(tagname);
  };

  // HTML5 classList API
  function supportsClassList() {
    return document.documentElement.classList;
  }

  exports.Dom = Dom;
});