'use strict';

/**
 * @ngdoc directive
 * @name ng.directive:ngTransclude
 * @restrict AC
 *
 * @description
 * Directive that marks the insertion point for the transcluded DOM of the nearest parent directive that uses transclusion.
 *
 * Any existing content of the element that this directive is placed on will be removed before the transcluded content is inserted.
 *
 * @element ANY
 *
 * @example
   <doc:example module="transclude">
     <doc:source>
       <script>
         function Ctrl($scope) {
           $scope.title = 'Lorem Ipsum';
           $scope.text = 'Neque porro quisquam est qui dolorem ipsum quia dolor...';
         }

         angular.module('transclude', [])
          .directive('pane', function(){
             return {
               restrict: 'E',
               transclude: true,
               scope: { title:'@' },
               template: '<div style="border: 1px solid black;">' +
                           '<div style="background-color: gray">{{title}}</div>' +
                           '<div ng-transclude></div>' +
                         '</div>'
             };
         });
       </script>
       <div ng-controller="Ctrl">
         <input ng-model="title"><br>
         <textarea ng-model="text"></textarea> <br/>
         <pane title="{{title}}">{{text}}</pane>
       </div>
     </doc:source>
     <doc:scenario>
        it('should have transcluded', function() {
          input('title').enter('TITLE');
          input('text').enter('TEXT');
          expect(binding('title')).toEqual('TITLE');
          expect(binding('text')).toEqual('TEXT');
        });
     </doc:scenario>
   </doc:example>
 *
 */
var ngTranscludeDirective = ngDirective({
  controller: ['$element', '$transclude', function($element, $transclude) {
    if (!$transclude) {
      throw minErr('ngTransclude')('orphan',
          'Illegal use of ngTransclude directive in the template! ' +
          'No parent directive that requires a transclusion found. ' +
          'Element: {0}',
          startingTag($element));
    }

    // remember the transclusion fn but call it during linking so that we don't process transclusion before directives on
    // the parent element even when the transclusion replaces the current element. (we can't use priority here because
    // that applies only to compile fns and not controllers
    this.$transclude = $transclude;
  }],

  link: function($scope, $element, $attrs, controller) {
    controller.$transclude(function(clone) {
      $element.empty();
      $element.append(clone);
    });
  }
});
