/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you 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.
   */
  
  package org.apache.myfaces.custom.tree2;
  
  
  import org.apache.myfaces.component.html.ext.HtmlGraphicImage;
  import org.apache.myfaces.renderkit.html.util.AddResource;
  import org.apache.myfaces.renderkit.html.util.AddResourceFactory;
  import org.apache.myfaces.shared_tomahawk.renderkit.html.HTML;
  import org.apache.myfaces.shared_tomahawk.renderkit.html.HtmlRendererUtils;
  import org.apache.myfaces.shared_tomahawk.renderkit.RendererUtils;
  
  import javax.faces.component.NamingContainer;
  import javax.faces.component.UIComponent;
  import javax.faces.component.UICommand;
  import javax.faces.component.UIGraphic;
  import javax.faces.component.UIViewRoot;
  import javax.faces.component.UIParameter;
  import javax.faces.context.FacesContext;
  import javax.faces.context.ResponseWriter;
  import javax.faces.render.Renderer;
  
  import java.io.IOException;
  import java.io.UnsupportedEncodingException;
  import java.util.Map;
  import java.util.Iterator;
  import java.net.URLDecoder;
  import javax.servlet.http.Cookie;
  import java.util.HashMap;
  
  /**
   * @JSFRenderer
   *   renderKitId = "HTML_BASIC" 
   *   family = "org.apache.myfaces.HtmlTree2"
   *   type = "org.apache.myfaces.HtmlTree2"
   *   
   * @author Sean Schofield
   * @author Chris Barlow
   * @author Hans Bergsten (Some code taken from an example in his O'Reilly JavaServer Faces book. Copied with permission)
   * @version $Revision: 987802 $ $Date: 2010-08-21 12:41:17 -0500 (Sat, 21 Aug 2010) $
   */
  public class HtmlTreeRenderer extends Renderer
  {
      protected static final String TOGGLE_SPAN = "org.apache.myfaces.tree.TOGGLE_SPAN";
      protected static final String ROOT_NODE_ID = "0";
  
      private static final String NAV_COMMAND = "org.apache.myfaces.tree.NAV_COMMAND";
      private static final String ENCODING = "UTF-8";
      private static final String ATTRIB_DELIM = ";";
      private static final String ATTRIB_KEYVAL = "=";
      private static final String NODE_STATE_EXPANDED = "x";
      private static final String NODE_STATE_CLOSED = "c";
      private static final String SEPARATOR = String.valueOf(NamingContainer.SEPARATOR_CHAR);
      private static final String IMAGE_PREFIX = "t2";
      private static final String TOGGLE_ID = "t2g";
  
      private static final int NOTHING = 0;
      private static final int CHILDREN = 1;
      private static final int EXPANDED = 2;
      private static final int LINES = 4;
      private static final int LAST = 8;
      private int counter = 0;
  
      // see superclass for documentation
      public boolean getRendersChildren()
      {
          return true;
      }
  
      private void restoreStateFromCookies(FacesContext context, UIComponent component) {
          String nodeId = null;
          HtmlTree tree = (HtmlTree)component;
          TreeState state = tree.getDataModel().getTreeState();
  
          Map cookieMap = context.getExternalContext().getRequestCookieMap();
          Cookie treeCookie = (Cookie)cookieMap.get(component.getId());
          if (treeCookie == null || treeCookie.getValue() == null)
          {
              return;
          }
  
          String nodeState = null;
         Map attrMap = getCookieAttr(treeCookie);
         Iterator i = attrMap.keySet().iterator();
         while (i.hasNext())
         {
             nodeId = (String)i.next();
             nodeState = (String)attrMap.get(nodeId);
 
             if (NODE_STATE_EXPANDED.equals(nodeState))
             {
                 if (!state.isNodeExpanded(nodeId))
                 {
                     state.toggleExpanded(nodeId);
                 }
             }
             else if (NODE_STATE_CLOSED.equals(nodeState))
             {
                 if (state.isNodeExpanded(nodeId))
                 {
                     state.toggleExpanded(nodeId);
                 }
             }
         }
     }
 
 
     public void decode(FacesContext context, UIComponent component)
     {
         super.decode(context, component);
 
         // see if one of the nav nodes was clicked, if so, then toggle appropriate node
         String nodeId = null;
         HtmlTree tree = (HtmlTree)component;
 
         if (tree.isClientSideToggle() && tree.isPreserveToggle())
         {
             restoreStateFromCookies(context, component);
         }
         else
         {
             nodeId = (String)context.getExternalContext().getRequestParameterMap().get(tree.getId() + SEPARATOR + NAV_COMMAND);
 
             if (nodeId == null || nodeId.equals(""))
             {
                 return;
             }
 
             component.queueEvent(new ToggleExpandedEvent(component, nodeId));
         }
     }
 
     public void encodeBegin(FacesContext context, UIComponent component) throws IOException
     {
         // Fixes TOMAHAWK-437
         //HtmlTree tree = (HtmlTree)component;
         //if (!tree.getDataModel().getTreeState().isTransient()
         //        && tree.isClientSideToggle()
         //        && tree.isPreserveToggle())
         //{
         //    restoreStateFromCookies(context, component);
         //}
 
         // write javascript functions
         encodeJavascript(context, component);
     }
 
     /**
      * Renders the whole tree.  It generates a <code>&lt;span></code> element with an <code>id</code>
      * attribute if the component has been given an explicit ID.  The model nodes are rendered
      * recursively by the private <code>encodeNodes</code> method.
      *
      * @param context FacesContext
      * @param component The component whose children are to be rendered
      * @throws IOException
      */
     public void encodeChildren(FacesContext context, UIComponent component) throws IOException
     {
         HtmlTree tree = (HtmlTree)component;
 
         if (!component.isRendered()) return;
         if (tree.getValue() == null) return;
 
         ResponseWriter out = context.getResponseWriter();
         String clientId = null;
 
         if (component.getId() != null && !component.getId().startsWith(UIViewRoot.UNIQUE_ID_PREFIX))
         {
             clientId = component.getClientId(context);
         }
 
         boolean isOuterSpanUsed = false;
 
         if (clientId != null)
         {
             isOuterSpanUsed = true;
             out.startElement("span", component);
             out.writeAttribute("id", clientId, "id");
         }
 
         boolean clientSideToggle = tree.isClientSideToggle();
         boolean showRootNode = tree.isShowRootNode();
 
         TreeState state = tree.getDataModel().getTreeState();
         TreeWalker walker = tree.getDataModel().getTreeWalker();
         walker.reset();
         walker.setTree(tree);
 
         walker.setCheckState(!clientSideToggle); // walk all nodes in client mode
 
         if (showRootNode)
         {
             // encode the tree (starting with the root node)
             if (walker.next())
             {
                 encodeTree(context, out, tree, walker);
             }
         }
         else
         {
             // skip the root node
             walker.next();
             TreeNode rootNode = tree.getNode();
 
             // now mark the root as expanded (so we don't stop there)
             String rootNodeId = tree.getNodeId();
             if(!state.isNodeExpanded(rootNodeId))
             {
                 state.toggleExpanded(rootNodeId);
             }
 
             // now encode each of the nodes in the level immediately below the root
             for (int i=0; i < rootNode.getChildCount(); i++)
             {
                 if (walker.next())
                 {
                     encodeTree(context, out, tree, walker);
                 }
             }
         }
 
         // reset the current node id once we're done encoding everything
         tree.setNodeId(null);
 
         if (isOuterSpanUsed)
         {
             out.endElement("span");
         }
     }
 
     /**
      * Encodes the tree and its children.
      *
      * @param context FacesContext
      * @param out ResponseWriter
      * @param tree HtmlTree
      * @param walker TreeWalker
      * @throws IOException
      */
     protected void encodeTree(FacesContext context, ResponseWriter out, HtmlTree tree, TreeWalker walker)
         throws IOException
     {
         boolean clientSideToggle = tree.isClientSideToggle();
 
         // encode the current node
         HtmlRendererUtils.writePrettyLineSeparator(context);
         beforeNodeEncode(context, out, tree);
         encodeCurrentNode(context, out, tree);
         afterNodeEncode(context, out);
 
         // if client side toggling is on, add a span to be used for displaying/hiding children
         if (clientSideToggle)
         {
             String spanId = TOGGLE_SPAN + ":" + tree.getClientId(context) + ":" + tree.getNodeId();
 
             out.startElement(HTML.SPAN_ELEM, tree);
             out.writeAttribute(HTML.ID_ATTR, spanId, null);
 
             if (tree.isNodeExpanded())
             {
                 out.writeAttribute(HTML.STYLE_ATTR, "display:block", null);
             }
             else
             {
                 out.writeAttribute(HTML.STYLE_ATTR, "display:none", null);
             }
         }
 
         TreeNode node = tree.getNode();
 
         for (int i=0; i < node.getChildCount(); i++)
         {
             if (walker.next())
             {
                 encodeTree(context, out, tree, walker);
             }
         }
 
         if (clientSideToggle)
         {
             out.endElement(HTML.SPAN_ELEM);
         }
     }
 
     /**
      * Encodes the current node.  It is protected so that custom {@link Renderer}s can extend it.  That might be useful
      * if you would like to render additional per node information besides the tree node.
      *
      * @param context FacesContext
      * @param out ResponseWriter
      * @param tree HtmlTree
      * @throws IOException
      */
     protected void encodeCurrentNode(FacesContext context, ResponseWriter out, HtmlTree tree)
         throws IOException
     {
         TreeNode node = tree.getNode();
 
         // set configurable values
         boolean showRootNode = tree.isShowRootNode();
         boolean showNav = tree.isShowNav();
         boolean showLines = tree.isShowLines();
         boolean clientSideToggle = tree.isClientSideToggle();
 
         if (clientSideToggle)
         {
             // we must show the nav icons if client side toggle is enabled (regardless of what user says)
             showNav = true;
         }
 
         UIComponent nodeTypeFacet = tree.getFacet(node.getType());
         UIComponent nodeImgFacet = null;
 
         if (nodeTypeFacet == null)
         {
             throw new IllegalArgumentException("Unable to locate facet with the name: " + node.getType());
         }
 
         // render node padding
         String[] pathInfo = tree.getPathInformation(tree.getNodeId());
         int paddingLevel = pathInfo.length - 1;
 
         for (int i = (showRootNode ? 0 : 1); i < paddingLevel; i++)
         {
             boolean lastChild = tree.isLastChild((String)pathInfo[i]);
             String lineSrc = (!lastChild && showLines)
                              ? getImageSrc(context, tree, "line-trunk.gif", true)
                              : getImageSrc(context, tree, "spacer.gif", true);
             String altString = (!lastChild && showLines)
                              ? "line trunk"
                              : "spacer";             
             
 
             out.startElement(HTML.TD_ELEM, tree);
             out.writeAttribute(HTML.WIDTH_ATTR, "19", null);
             out.writeAttribute(HTML.HEIGHT_ATTR, "100%", null);
             out.writeURIAttribute(HTML.STYLE_ATTR, "background-image:url('" + lineSrc + "');", null); //we use "style" because "background" is no valid xhtml attribute for td
             out.startElement(HTML.IMG_ELEM, tree);
             out.writeURIAttribute(HTML.SRC_ATTR, lineSrc, null);
             out.writeAttribute(HTML.WIDTH_ATTR, "19", null);
             out.writeAttribute(HTML.HEIGHT_ATTR, "18", null);
             out.writeAttribute(HTML.BORDER_ATTR, "0", null);
             out.writeAttribute(HTML.ALT_ATTR, altString, null); // placing a suitable description for the alt.
             out.endElement(HTML.IMG_ELEM);
             out.endElement(HTML.TD_ELEM);
         }
 
         if (showNav)
         {
             nodeImgFacet = encodeNavigation(context, out, tree);
         }
 
         // render node
         out.startElement(HTML.TD_ELEM, tree);
         if (nodeImgFacet != null)
         {
             RendererUtils.renderChild(context, nodeImgFacet);
         }
         RendererUtils.renderChild(context, nodeTypeFacet);
         out.endElement(HTML.TD_ELEM);
     }
 
     protected void beforeNodeEncode(FacesContext context, ResponseWriter out, HtmlTree tree)
         throws IOException
     {
         out.startElement(HTML.TABLE_ELEM, tree);
         out.writeAttribute(HTML.CELLPADDING_ATTR, "0", null);
         out.writeAttribute(HTML.CELLSPACING_ATTR, "0", null);
         out.writeAttribute(HTML.BORDER_ATTR, "0", null);
         out.startElement(HTML.TR_ELEM, tree);
     }
 
     protected void afterNodeEncode(FacesContext context, ResponseWriter out)
         throws IOException
     {
         out.endElement(HTML.TR_ELEM);
         out.endElement(HTML.TABLE_ELEM);
     }
 
     /**
      * Handles the encoding related to the navigation functionality.
      *
      * @param context FacesContext
      * @param out ResponseWriter
      * @param tree HtmlTree
      * @return The additional navigation image to display inside the node (if any).  Only used with client-side toggle.
      * @throws IOException
      */
     private UIComponent encodeNavigation(FacesContext context, ResponseWriter out, HtmlTree tree)
         throws IOException
     {
         TreeNode node = tree.getNode();
         String nodeId = tree.getNodeId();
         String spanId = TOGGLE_SPAN + ":" + tree.getClientId(context) + ":" + nodeId;//TOGGLE_SPAN + nodeId;
         boolean showLines = tree.isShowLines();
         boolean clientSideToggle = tree.isClientSideToggle();
         UIComponent nodeTypeFacet = tree.getFacet(node.getType());
         String navSrc = null;
         String altSrc = null;
         UIComponent nodeImgFacet = null;
 
         int bitMask = NOTHING;
         bitMask += (node.isLeaf()) ? NOTHING : CHILDREN;
         if (bitMask == CHILDREN) // if there are no children, ignore expand state -> more flexible with dynamic tree-structures
             bitMask += (tree.isNodeExpanded()) ? EXPANDED : NOTHING;
         bitMask += (tree.isLastChild(tree.getNodeId())) ? LAST : NOTHING;
         bitMask += (showLines) ? LINES : NOTHING;
 
         switch (bitMask)
         {
             case (NOTHING):
 
             case (LAST):
                 navSrc = "spacer.gif";
                 break;
 
             case (LINES):
                 navSrc = "line-middle.gif";
                 break;
 
             case (LINES + LAST):
                 navSrc = "line-last.gif";
                 break;
 
             case (CHILDREN):
 
             case (CHILDREN + LAST):
                 navSrc = "nav-plus.gif";
                 altSrc = "nav-minus.gif";
                 break;
 
             case (CHILDREN + LINES):
 
                 navSrc = "nav-plus-line-middle.gif";
                 altSrc = "nav-minus-line-middle.gif";
                 break;
 
             case (CHILDREN + LINES + LAST):
 
                 navSrc = "nav-plus-line-last.gif";
                 altSrc = "nav-minus-line-last.gif";
                 break;
 
             case (CHILDREN + EXPANDED):
 
             case (CHILDREN + EXPANDED + LAST):
                 navSrc = "nav-minus.gif";
                 altSrc = "nav-plus.gif";
                 break;
 
             case (CHILDREN + EXPANDED + LINES):
                 navSrc = "nav-minus-line-middle.gif";
                 altSrc = "nav-plus-line-middle.gif";
                 break;
 
             case (CHILDREN + EXPANDED + LINES + LAST):
                 navSrc = "nav-minus-line-last.gif";
                 altSrc = "nav-plus-line-last.gif";
                 break;
 
             // unacceptable bitmask combinations
 
             case (EXPANDED + LINES):
             case (EXPANDED + LINES + LAST):
             case (EXPANDED):
             case (EXPANDED + LAST):
 
                 throw new IllegalStateException("Encountered a node ["+ nodeId + "] + with an illogical state.  " +
                                                 "Node is expanded but it is also considered a leaf (a leaf cannot be considered expanded.");
 
             default:
                 // catch all for any other combinations
                 throw new IllegalArgumentException("Invalid bit mask of " + bitMask);
         }
 
         // adjust navSrc and altSrc so that the images can be retrieved using the extensions filter
         String navSrcUrl = getImageSrc(context, tree, navSrc, false);
         navSrc = getImageSrc(context, tree, navSrc, true);
         altSrc = getImageSrc(context, tree, altSrc, true);
 
         // render nav cell
         out.startElement(HTML.TD_ELEM, tree);
         out.writeAttribute(HTML.WIDTH_ATTR, "19", null);
         out.writeAttribute(HTML.HEIGHT_ATTR, "100%", null);
         out.writeAttribute("valign", "top", null);
 
         if ((bitMask & LINES)!=0 && (bitMask & LAST)==0)
         {
             //out.writeURIAttribute("background", getImageSrc(context, tree, "line-trunk.gif", true), null);
             out.writeURIAttribute(HTML.STYLE_ATTR, "background-image:url('" + getImageSrc(context, tree, "line-trunk.gif", true) + "');", null); 
         }
 
 //      add the appropriate image for the nav control
         UIGraphic image = new HtmlGraphicImage();
         String imageId = IMAGE_PREFIX+(counter++);
         image.setId(imageId);
         image.setUrl(navSrcUrl);
         
         Map imageAttrs = image.getAttributes();
         imageAttrs.put(HTML.WIDTH_ATTR, "19");
         imageAttrs.put(HTML.HEIGHT_ATTR, "18");
         imageAttrs.put(HTML.BORDER_ATTR, "0");
         imageAttrs.put(HTML.ALT_ATTR, "Nav control image"); // placing a suitable description for the alt.
 
         if (clientSideToggle)
         {
             /**
              * With client side toggle, user has the option to specify open/closed images for the node (in addition to
              * the navigtion ones provided by the component.)
              */
             String expandImgSrc = "";
             String collapseImgSrc = "";
             String nodeImageId = "";
 
             UIComponent expandFacet = nodeTypeFacet.getFacet("expand");
             if (expandFacet != null)
             {
                 UIGraphic expandImg = (UIGraphic)expandFacet;
                 expandImgSrc = context.getApplication().getViewHandler().getResourceURL(context, expandImg.getUrl());
                 if (expandImg.isRendered())
                 {
                     expandImg.setId(imageId + NODE_STATE_EXPANDED);
                     expandImg.setParent(tree);
                     nodeImageId = expandImg.getClientId(context);
                     nodeImgFacet = expandFacet;
                 }
             }
 
             UIComponent collapseFacet = nodeTypeFacet.getFacet("collapse");
             if (collapseFacet != null)
             {
                 UIGraphic collapseImg = (UIGraphic)collapseFacet;
                 collapseImgSrc = context.getApplication().getViewHandler().getResourceURL(context, collapseImg.getUrl());
                 if (collapseImg.isRendered())
                 {
                     collapseImg.setId(imageId + NODE_STATE_CLOSED);
                     collapseImg.setParent(tree);
                     nodeImageId = collapseImg.getClientId(context);
                     nodeImgFacet = collapseFacet;
                 }
             }
 
             image.setParent(tree);
             if (node.getChildCount() > 0)
             {
                 String onClick = new StringBuffer()
                     .append("treeNavClick('")
                     .append(spanId)
                     .append("', '")
                     .append(image.getClientId(context))
                     .append("', '")
                     .append(navSrc)
                     .append("', '")
                     .append(altSrc)
                     .append("', '")
                     .append(nodeImageId)
                     .append("', '")
                     .append(expandImgSrc)
                     .append("', '")
                     .append(collapseImgSrc)
                     .append("', '")
                     .append(tree.getId())
                     .append("', '")
                     .append(nodeId)
                     .append("');")
                     .toString();
 
                 imageAttrs.put(HTML.ONCLICK_ATTR, onClick);
                 imageAttrs.put(HTML.STYLE_ATTR, "cursor:pointer;cursor:hand");
             }
             RendererUtils.renderChild(context, image);
 
         }
         else
         {
             if (node.getChildCount() > 0)
             {
                 // set up the expand control and remove whatever children (if any) this control had previously
                 UICommand expandControl = tree.getExpandControl();
                 expandControl.getChildren().clear();
                 expandControl.setId(TOGGLE_ID);
 
                 UIParameter param = new UIParameter();
                 param.setName(tree.getId() + NamingContainer.SEPARATOR_CHAR + NAV_COMMAND);
                 param.setValue(tree.getNodeId());
                 expandControl.getChildren().add(param);
                 expandControl.getChildren().add(image);
 
                 RendererUtils.renderChild(context, expandControl);
             }
             else
             {
                 RendererUtils.renderChild(context, image);
             }
         }
         out.endElement(HTML.TD_ELEM);
 
         return nodeImgFacet;
     }
 
     /**
      * Encodes any stand-alone javascript functions that are needed.  Uses either the extension filter, or a
      * user-supplied location for the javascript files.
      *
      * @param context FacesContext
      * @param component UIComponent
      * @throws IOException
      */
     private void encodeJavascript(FacesContext context, UIComponent component) throws IOException
     {
         // render javascript function for client-side toggle (it won't be used if user has opted for server-side toggle)
         String javascriptLocation = ((HtmlTree)component).getJavascriptLocation();
         AddResource addResource = AddResourceFactory.getInstance(context);
         if (javascriptLocation == null)
         {
             addResource.addJavaScriptAtPosition(context, AddResource.HEADER_BEGIN, HtmlTreeRenderer.class, "javascript/tree.js");
             addResource.addJavaScriptAtPosition(context, AddResource.HEADER_BEGIN, HtmlTreeRenderer.class, "javascript/cookielib.js");
         }
         else
         {
             addResource.addJavaScriptAtPosition(context, AddResource.HEADER_BEGIN, javascriptLocation + "/tree.js");
             addResource.addJavaScriptAtPosition(context, AddResource.HEADER_BEGIN, javascriptLocation + "/cookielib.js");
         }
     }
 
     /**
      * Get the appropriate image src location.  Uses the extension filter mechanism for images if no image
      * location has been specified.
      *
      * @param context The {@link FacesContext}.  NOTE: If <code>null</code> then context path information
      *    will not be used with extensions filter (assuming no imageLocation specified.)
      * @param component UIComponent
      * @param imageName The name of the image file to use.
      * @return The image src information.
      */
     private String getImageSrc(FacesContext context, UIComponent component, String imageName, boolean withContextPath)
     {
         String imageLocation = ((HtmlTree)component).getImageLocation();
         AddResource addResource = AddResourceFactory.getInstance(context);
         if (imageLocation == null)
         {
             return addResource.getResourceUri(context, HtmlTreeRenderer.class,
                                               "images/" + imageName, withContextPath);
         }
         else
         {
             return addResource.getResourceUri(context, imageLocation + "/" + imageName, withContextPath);
         }
     }
 
     /**
      * Helper method for getting the boolean value of an attribute.  If the attribute is not specified,
      * then return the default value.
      *
      * @param component The component for which the attributes are to be checked.
      * @param attributeName The name of the boolean attribute.
      * @param defaultValue The default value of the attribute (to be returned if no value found).
      * @return boolean
      */
     protected boolean getBoolean(UIComponent component, String attributeName, boolean defaultValue)
     {
         Boolean booleanAttr = (Boolean)component.getAttributes().get(attributeName);
 
         if (booleanAttr == null)
         {
             return defaultValue;
         }
         else
         {
             return booleanAttr.booleanValue();
         }
     }
 
     private Map getCookieAttr(Cookie cookie)
     {
         Map attribMap = new HashMap();
         try
         {
             String cookieValue = URLDecoder.decode(cookie.getValue(),ENCODING);
             String[] attribArray = cookieValue.split(ATTRIB_DELIM);
             for (int j = 0; j < attribArray.length; j++)
             {
                 int index = attribArray[j].indexOf(ATTRIB_KEYVAL);
                 String name = attribArray[j].substring(0, index);
                 String value = attribArray[j].substring(index + 1);
                 attribMap.put(name, value);
             }
         }
         catch (UnsupportedEncodingException e)
         {
             throw new RuntimeException("Error parsing tree cookies", e);
         }
         return attribMap;
     }
 }