/*
 * Copyright (c) 2011, the Dart project authors.
 * 
 * Licensed under the Eclipse Public License v1.0 (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.eclipse.org/legal/epl-v10.html
 * 
 * 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 com.google.dart.tools.ui.internal.viewsupport;

import com.google.dart.tools.ui.DartX;

import org.eclipse.core.resources.IStorage;
import org.eclipse.core.runtime.IPath;
import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.jface.viewers.LabelProvider;
import org.eclipse.swt.graphics.Image;
import org.eclipse.ui.IEditorRegistry;
import org.eclipse.ui.IFileEditorMapping;
import org.eclipse.ui.ISharedImages;
import org.eclipse.ui.PlatformUI;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

/**
 * Standard label provider for IStorage objects. Use this class when you want to present IStorage
 * objects in a viewer.
 */
public class StorageLabelProvider extends LabelProvider {

  private IEditorRegistry fEditorRegistry = null;
  private Map<String, Image> fJarImageMap = new HashMap<String, Image>(10);
  private Image fDefaultImage;

  /*
   * (non-Javadoc)
   * 
   * @see IBaseLabelProvider#dispose
   */
  @Override
  public void dispose() {
    if (fJarImageMap != null) {
      Iterator<Image> each = fJarImageMap.values().iterator();
      while (each.hasNext()) {
        Image image = each.next();
        image.dispose();
      }
      fJarImageMap = null;
    }
    fDefaultImage = null;
  }

  /*
   * (non-Javadoc)
   * 
   * @see ILabelProvider#getImage
   */
  @Override
  public Image getImage(Object element) {
    if (element instanceof IStorage) {
      return getImageForJarEntry((IStorage) element);
    }

    return super.getImage(element);
  }

  /*
   * (non-Javadoc)
   * 
   * @see ILabelProvider#getText
   */
  @Override
  public String getText(Object element) {
    if (element instanceof IStorage) {
      return ((IStorage) element).getName();
    }
    return super.getText(element);
  }

  private Image getDefaultImage() {
    if (fDefaultImage == null) {
      fDefaultImage = PlatformUI.getWorkbench().getSharedImages().getImage(
          ISharedImages.IMG_OBJ_FILE);
    }
    return fDefaultImage;
  }

  private IEditorRegistry getEditorRegistry() {
    if (fEditorRegistry == null) {
      fEditorRegistry = PlatformUI.getWorkbench().getEditorRegistry();
    }
    return fEditorRegistry;
  }

  /*
   * Gets and caches an image for a JarEntryFile. The image for a JarEntryFile is retrieved from the
   * EditorRegistry.
   */
  private Image getImageForJarEntry(IStorage element) {
    DartX.todo();
//    if (element instanceof IJarEntryResource
//        && !((IJarEntryResource) element).isFile()) {
//      return PlatformUI.getWorkbench().getSharedImages().getImage(
//          ISharedImages.IMG_OBJ_FOLDER);
//    }

    if (fJarImageMap == null) {
      return getDefaultImage();
    }

    if (element == null || element.getName() == null) {
      return getDefaultImage();
    }

    // Try to find icon for full name
    String name = element.getName();
    Image image = fJarImageMap.get(name);
    if (image != null) {
      return image;
    }
    IFileEditorMapping[] mappings = getEditorRegistry().getFileEditorMappings();
    int i = 0;
    while (i < mappings.length) {
      if (mappings[i].getLabel().equals(name)) {
        break;
      }
      i++;
    }
    String key = name;
    if (i == mappings.length) {
      // Try to find icon for extension
      IPath path = element.getFullPath();
      if (path == null) {
        return getDefaultImage();
      }
      key = path.getFileExtension();
      if (key == null) {
        return getDefaultImage();
      }
      image = fJarImageMap.get(key);
      if (image != null) {
        return image;
      }
    }

    // Get the image from the editor registry
    ImageDescriptor desc = getEditorRegistry().getImageDescriptor(name);
    image = desc.createImage();

    fJarImageMap.put(key, image);

    return image;
  }
}