Merged from BRANCHES/DEV/KEVINR:

. NodeInfo panel and Ajax client library
 - Rewrite of Node Info panel
 - Alfresco common DOM methods refactored into namespaced object (YUI/Dojo style) Alfresco.Dom
 - Addition of useful DOM and 'smart' alignment method to common.js
 - OpenSearch now uses additional namespace for it's global method handlers: Alfresco.OpenSearchEngine
 - Temporary icons added for pop-up node info panel
. Additional FreeMarker model API method "cropContent(contentprop, length)" to return the first N bytes of a content stream - auto converted to plain/text from all supported transformation mimetypes
. DownloadContentServlet now handles ContentIOException more gracefully
. AbstractContentReader fixed to handle empty file data when requesting N characters from a content stream

. Yahoo scripts move to PageTag rendering as appropriate
. Refactoring of existing ajax components that output Yahoo scripts

git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@5253 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261

source/java/org/alfresco/repo/content/AbstractContentReader.java

@@ -400,10 +400,9 @@ public abstract class AbstractContentReader extends AbstractContentAccessor impl
             }
             // read it all, if possible
             int count = reader.read(buffer, 0, length);
-            // there may have been fewer characters - create a new string
+            
-            String result = new String(buffer, 0, count);
+            // there may have been fewer characters - create a new string as the result
-            // done
+            return (count != -1 ? new String(buffer, 0, count) : "");
-            return result;
         }
         catch (IOException e)
         {

source/java/org/alfresco/repo/content/MimetypeMap.java

@@ -65,6 +65,7 @@ public class MimetypeMap implements MimetypeService
     public static final String MIMETYPE_IMAGE_JPEG = "image/jpeg";
     public static final String MIMETYPE_IMAGE_RGB = "image/x-rgb";
     public static final String MIMETYPE_IMAGE_SVG = "image/svg";
+    public static final String MIMETYPE_IMAGE_PNG = "image/png";
     public static final String MIMETYPE_JAVASCRIPT = "application/x-javascript";
     public static final String MIMETYPE_ZIP = "application/zip";
     public static final String MIMETYPE_OPENSEARCH_DESCRIPTION = "application/opensearchdescription+xml";

source/java/org/alfresco/repo/template/CropContentMethod.java

@@ -0,0 +1,73 @@
+/*
+ * Copyright (C) 2005-2007 Alfresco Software Limited.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+
+ * As a special exception to the terms and conditions of version 2.0 of 
+ * the GPL, you may redistribute this Program in connection with Free/Libre 
+ * and Open Source Software ("FLOSS") applications as described in Alfresco's 
+ * FLOSS exception.  You should have recieved a copy of the text describing 
+ * the FLOSS exception, and it is also available here: 
+ * http://www.alfresco.com/legal/licensing
+ */
+package org.alfresco.repo.template;
+
+import java.util.List;
+
+import org.alfresco.model.ContentModel;
+import org.alfresco.service.cmr.repository.TemplateNode;
+import org.alfresco.service.cmr.repository.TemplateNode.TemplateContentData;
+
+import freemarker.ext.beans.BeanModel;
+import freemarker.template.TemplateMethodModelEx;
+import freemarker.template.TemplateModelException;
+import freemarker.template.TemplateNumberModel;
+
+/**
+ * @author Kevin Roast
+ * 
+ * FreeMarker custom method to return the first N characters of a content stream.
+ * <p>
+ * Usage: String cropContent(TemplateContentData content, int length)
+ */
+public final class CropContentMethod implements TemplateMethodModelEx
+{
+    /**
+     * @see freemarker.template.TemplateMethodModel#exec(java.util.List)
+     */
+    public Object exec(List args) throws TemplateModelException
+    {
+        String result = null;
+        
+        if (args.size() == 2)
+        {
+            Object arg0 = args.get(0);
+            Object arg1 = args.get(1);
+            
+            if (arg0 instanceof BeanModel && arg1 instanceof TemplateNumberModel)
+            {
+                Object wrapped = ((BeanModel)arg0).getWrappedObject();
+                if (wrapped instanceof TemplateContentData)
+                {
+                   int bytes = ((TemplateNumberModel)arg1).getAsNumber().intValue();
+                   
+                   result = ((TemplateContentData)wrapped).getContentAsText(bytes);
+                }
+            }
+        }
+        
+        return result != null ? result : "";
+    }
+}

source/java/org/alfresco/service/cmr/repository/TemplateNode.java

@@ -36,6 +36,8 @@ import java.util.Map;
 import java.util.Set;
 
 import org.alfresco.model.ContentModel;
+import org.alfresco.repo.action.executer.TransformActionExecuter;
+import org.alfresco.repo.content.MimetypeMap;
 import org.alfresco.repo.security.permissions.AccessDeniedException;
 import org.alfresco.repo.template.LuceneSearchResultsMap;
 import org.alfresco.repo.template.NamePathResultsMap;
@@ -793,6 +795,64 @@ public class TemplateNode implements Serializable
             return (reader != null && reader.exists()) ? reader.getContentString() : "";
         }
         
+        /**
+         * @return the content stream to the specified maximum length in characters
+         */
+        public String getContent(int length)
+        {
+            ContentService contentService = services.getContentService();
+            ContentReader reader = contentService.getReader(nodeRef, property);
+            
+            return (reader != null && reader.exists()) ? reader.getContentString(length) : "";
+        }
+        
+        /**
+         * @param length      Length of the character stream to return, or -1 for all
+         * 
+         * @return the binary content stream converted to text using any available transformer
+         *         if fails to convert then null will be returned
+         */
+        public String getContentAsText(int length)
+        {
+            String result = null;
+            
+            if (MimetypeMap.MIMETYPE_TEXT_PLAIN.equals(mimetype))
+            {
+                result = getContent(length);
+            }
+            else
+            {
+                // get the content reader
+                ContentService contentService = services.getContentService();
+                ContentReader reader = contentService.getReader(nodeRef, property);
+                
+                // get the writer and set it up for text convert
+                ContentWriter writer = contentService.getWriter(null, ContentModel.PROP_CONTENT, true);
+                writer.setMimetype("text/plain"); 
+                writer.setEncoding(reader.getEncoding());
+                
+                // try and transform the content
+                if (contentService.isTransformable(reader, writer))
+                {
+                    contentService.transform(reader, writer);
+                    
+                    ContentReader resultReader = writer.getReader();
+                    if (resultReader != null && reader.exists())
+                    {
+                       if (length != -1)
+                       {
+                           result = resultReader.getContentString(length);
+                       }
+                       else
+                       {
+                           result = resultReader.getContentString();
+                       }
+                    }
+                }
+            }
+            return result;
+        }
+        
         /**
          * @return 
          */