// Licensed under the Apache License, Version 2.0 (the "License"); you may not
// use this file except in compliance with the License.  You may obtain a copy
// of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
// License for the specific language governing permissions and limitations under
// the License.

(function($) {

  $.fn.makeEditable = function(options) {
    options = $.extend({
      allowEmpty: true,
      acceptLabel: "",
      cancelLabel: "",
      toolTip: "Double click to edit",

      // callbacks
      begin: function() { return true },
      accept: function(newValue, oldValue) {},
      cancel: function(oldValue) {},
      createInput: function(value) { return $("<input type='text'>") },
      prepareInput: function(input) {},
      end: function(keyCode) {},
      populate: function(value) { return value },
      validate: function() { return true }
    }, options || {});

    return this.each(function() {
      var elem = $(this);
      elem.attr("title", options.toolTip).dblclick(function() {
        var oldHtml = elem.html();
        var oldText = options.populate($.trim(elem.text()));

        if (!options.begin.apply(elem[0], [oldText])) {
          return;
        }

        var input = options.createInput.apply(elem[0], [oldText])
          .addClass("editinline").val(oldText)
          .dblclick(function() { return false; })
          .keydown(function(evt) {
            switch (evt.keyCode) {
              case 13: { // return
                if (!input.is("textarea")) applyChange(evt.keyCode);
                break;
              }
              case 27: { // escape
                cancelChange(evt.keyCode);
                break;
              }
              case 9: { // tab
                if (!input.is("textarea")) {
                  applyChange(evt.keyCode);
                  return false;
                }
              }
            }
          });

        function applyChange(keyCode) {
          var newText = input.val();
          if (newText == oldText) {
            cancelChange(keyCode);
            return true;
          }
          if ((!options.allowEmpty && !newText.length) ||
              !options.validate.apply(elem[0], [newText])) {
            input.addClass("invalid");
            return false;
          }
          input.remove();
          tools.remove();
          options.accept.apply(elem[0], [newText, oldText]);
          elem.removeClass("editinline-container")
          options.end.apply(elem[0], [keyCode]);
          return true;
        }

        function cancelChange(keyCode) {
          options.cancel.apply(elem[0], [oldText]);
          elem.html(oldHtml).removeClass("editinline-container");
          options.end.apply(elem[0], [keyCode]);
        }

        var tools = $("<span class='editinline-tools'></span>");
        $("<button type='button' class='apply'></button>")
          .text(options.acceptLabel).click(applyChange).appendTo(tools);
        $("<button type='button' class='cancel'></button>")
          .text(options.cancelLabel).click(cancelChange).appendTo(tools)

        elem.html("").append(tools).append(input)
          .addClass("editinline-container");
        options.prepareInput.apply(elem[0], [input[0]]);
        input.each(function() { this.focus(); this.select(); });
      });
    });
  }

})(jQuery);