/**
 * AccessibleBlockly
 *
 * Copyright 2016 Google Inc.
 * https://developers.google.com/blockly/
 *
 * 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.
 */

/**
 * @fileoverview Angular2 Component that details how a toolbox is rendered
 * in AccessibleBlockly. Also handles any interactions with the toolbox.
 * @author madeeha@google.com (Madeeha Ghori)
 */
blocklyApp.ToolboxView = ng.core
  .Component({
    selector: 'toolbox-view',
    template: `
      <h3 #toolboxTitle id="blockly-toolbox-title">Toolbox</h3>
      <ol #tree id="blockly-toolbox-tree" role="group" class="blocklyTree"
          *ngIf="makeArray(sightedToolbox) && makeArray(sightedToolbox).length > 0" 
          tabIndex="0" [attr.aria-labelledby]="toolboxTitle.id" 
          [attr.aria-activedescendant]="tree.getAttribute('aria-activedescendant') || tree.id + '-node0' " 
          (keydown)="treeService.onKeypress($event, tree)">
        <li #parent [id]="idMap['Parent' + i]" role="treeitem" 
            [ngClass]="{blocklyHasChildren: true,
                blocklyActiveDescendant: tree.getAttribute('aria-activedescendant') == idMap['Parent' + i]}" 
            *ngIf="toolboxHasCategories" *ngFor="#category of makeArray(sightedToolbox); #i=index" 
            aria-level="1" aria-selected=false>
          <!-- TODO(madeeha): There seems to be some bug in Angular that makes it 
          access index=undefined in the ngFor loop. This causes it to throw an error once it reaches line
          44. To combat this, we have added the div at line 43. Talk to fraser@.-->
          <div *ngIf="category && category.attributes">
            <label [id]="idMap['Label' + i]" #name>{{category.attributes.name.value}}</label>
            {{labelCategory(name, i, tree)}}
            <ol role="group" *ngIf="getToolboxWorkspace(category).topBlocks_.length > 0">
              <toolbox-tree-view *ngFor="#block of getToolboxWorkspace(category).topBlocks_" [level]=2 [block]="block" [displayBlockMenu]="true" [clipboardService]="clipboardService"></toolbox-tree-view>
            </ol>
          </div>
        </li>
        <div *ngIf="!toolboxHasCategories">
          <toolbox-tree-view *ngFor="#block of getToolboxWorkspace(toolboxCategories[0]).topBlocks_; #i=index" [level]=1 [block]="block" [displayBlockMenu]="true" [clipboardService]="clipboardService" [index]="i" [tree]="tree" [noCategories]="true"></toolbox-tree-view>
        </div>
      </ol>
    `,
    directives: [blocklyApp.ToolboxTreeView],
    providers: [blocklyApp.TreeService, blocklyApp.UtilsService],
  })
  .Class({
    constructor: [blocklyApp.TreeService, blocklyApp.UtilsService, function(_treeService, _utilsService) {
      this.sightedToolbox = document.getElementById('blockly-toolbox-xml');

      this.toolboxCategories = [];
      this.toolboxWorkspaces = Object.create(null);
      this.treeService = _treeService;
      this.utilsService = _utilsService;

      this.toolboxHasCategories = false;
    }],
    ngOnInit: function() {
      var elementsNeedingIds = [];
      var categories = this.makeArray(this.sightedToolbox);
      if (this.toolboxHasCategories) {
        for (var i = 0; i < categories.length; i++){
          elementsNeedingIds.push('Parent' + i);
          elementsNeedingIds.push('Label' + i);
        }
        this.idMap = this.utilsService.generateIds(elementsNeedingIds);
        this.idMap['Parent0'] = 'blockly-toolbox-tree-node0';
      }
    },
    labelCategory: function(label, i, tree) {
      var parent = label.parentNode;
      while (parent && parent.tagName != 'LI') {
        parent = parent.parentNode;
      }
      parent.setAttribute('aria-label', label.innerText);
      parent.id = 'blockly-toolbox-tree-node' + i;
      if (i == 0 && tree.getAttribute('aria-activedescendant') ==
        'blockly-toolbox-tree-node0') {
        this.treeService.setActiveDesc(parent, tree.id);
        parent.setAttribute('aria-selected', 'true');
      }
    },
    makeArray: function(val) {
      if (val) {
        if (this.toolboxCategories.length) {
          return this.toolboxCategories;
        } else {
          var categories = val.getElementsByTagName('category');
          if (categories.length) {
            this.toolboxHasCategories = true;
            this.toolboxCategories = Array.from(categories);
            return this.toolboxCategories;
          }
          this.toolboxHasCategories = false;
          this.toolboxCategories = [Array.from(val.children)];
          return this.toolboxCategories;
        }
      }
    },
    getToolboxWorkspace: function(categoryNode) {
      if (categoryNode.attributes && categoryNode.attributes.name) {
        var categoryName = categoryNode.attributes.name.value;
      } else {
        var categoryName = 'no-category';
      }
      if (this.toolboxWorkspaces[categoryName]) {
        return this.toolboxWorkspaces[categoryName];
      } else {
        var categoryWorkspace = new Blockly.Workspace();
        if (categoryName == 'no-category') {
          for (var i = 0; i < categoryNode.length; i++) {
            Blockly.Xml.domToBlock(categoryWorkspace, categoryNode[i]);
          }
        } else {
          Blockly.Xml.domToWorkspace(categoryNode, categoryWorkspace);
        }
        this.toolboxWorkspaces[categoryName] = categoryWorkspace;
        return this.toolboxWorkspaces[categoryName];
      }
    }
  });