/*******************************************************************************
 * Copyright (c) 2001, 2007 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *     Jens Lukowski/Innoopract - initial renaming/restructuring
 *     
 *******************************************************************************/
package org.eclipse.wst.xml.ui.views.contentoutline;

import org.eclipse.jface.action.IContributionItem;
import org.eclipse.jface.action.IMenuListener;
import org.eclipse.jface.action.IMenuManager;
import org.eclipse.jface.preference.IPreferenceStore;
import org.eclipse.jface.util.LocalSelectionTransfer;
import org.eclipse.jface.util.SafeRunnable;
import org.eclipse.jface.util.TransferDragSourceListener;
import org.eclipse.jface.util.TransferDropTargetListener;
import org.eclipse.jface.viewers.IContentProvider;
import org.eclipse.jface.viewers.ILabelProvider;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.StructuredSelection;
import org.eclipse.jface.viewers.TreeViewer;
import org.eclipse.swt.dnd.DND;
import org.eclipse.swt.dnd.DragSourceEvent;
import org.eclipse.swt.dnd.DropTargetEvent;
import org.eclipse.swt.dnd.Transfer;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.TableItem;
import org.eclipse.swt.widgets.TreeItem;
import org.eclipse.wst.sse.core.internal.provisional.IStructuredModel;
import org.eclipse.wst.sse.core.utils.StringUtils;
import org.eclipse.wst.sse.ui.internal.IReleasable;
import org.eclipse.wst.sse.ui.internal.contentoutline.PropertyChangeUpdateAction;
import org.eclipse.wst.sse.ui.internal.contentoutline.PropertyChangeUpdateActionContributionItem;
import org.eclipse.wst.sse.ui.internal.editor.EditorPluginImageHelper;
import org.eclipse.wst.sse.ui.internal.editor.EditorPluginImages;
import org.eclipse.wst.sse.ui.views.contentoutline.ContentOutlineConfiguration;
import org.eclipse.wst.xml.core.internal.contentmodel.CMAttributeDeclaration;
import org.eclipse.wst.xml.core.internal.contentmodel.CMDataType;
import org.eclipse.wst.xml.core.internal.contentmodel.CMElementDeclaration;
import org.eclipse.wst.xml.core.internal.contentmodel.modelquery.ModelQuery;
import org.eclipse.wst.xml.core.internal.modelquery.ModelQueryUtil;
import org.eclipse.wst.xml.ui.internal.XMLUIMessages;
import org.eclipse.wst.xml.ui.internal.XMLUIPlugin;
import org.eclipse.wst.xml.ui.internal.contentoutline.JFaceNodeContentProvider;
import org.eclipse.wst.xml.ui.internal.contentoutline.JFaceNodeLabelProvider;
import org.eclipse.wst.xml.ui.internal.contentoutline.XMLNodeActionManager;
import org.eclipse.wst.xml.ui.internal.dnd.DragNodeCommand;
import org.w3c.dom.Attr;
import org.w3c.dom.Element;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;

/**
 * Outline Configuration for generic XML support, expects that the viewer's
 * input will be the DOM Model.
 * 
 * @see org.eclipse.wst.sse.ui.views.contentoutline.ContentOutlineConfiguration
 * @since 1.0
 */
public class XMLContentOutlineConfiguration extends ContentOutlineConfiguration {
	private class ActionManagerMenuListener implements IMenuListener, IReleasable {
		private XMLNodeActionManager fActionManager;
		private TreeViewer fTreeViewer;

		public ActionManagerMenuListener(TreeViewer viewer) {
			fTreeViewer = viewer;
		}

		/*
		 * (non-Javadoc)
		 * 
		 * @see org.eclipse.jface.action.IMenuListener#menuAboutToShow(org.eclipse.jface.action.IMenuManager)
		 */
		public void menuAboutToShow(IMenuManager manager) {
			if (fActionManager == null) {
				fActionManager = createNodeActionManager(fTreeViewer);
			}
			fActionManager.fillContextMenu(manager, fTreeViewer.getSelection());
		}

		/*
		 * (non-Javadoc)
		 * 
		 * @see org.eclipse.wst.sse.ui.internal.IReleasable#release()
		 */
		public void release() {
			fTreeViewer = null;
			if (fActionManager != null) {
				fActionManager.setModel(null);
			}
		}
	}

	private class AttributeShowingLabelProvider extends JFaceNodeLabelProvider {
		/*
		 * (non-Javadoc)
		 * 
		 * @see org.eclipse.jface.viewers.ILabelProvider#getText(java.lang.Object)
		 */
		public String getText(Object o) {
			StringBuffer text = new StringBuffer(super.getText(o));
			if (o instanceof Node) {
				Node node = (Node) o;
				if (node.getNodeType() == Node.ELEMENT_NODE && fShowAttributes) {
					// https://bugs.eclipse.org/bugs/show_bug.cgi?id=88444
					if (node.hasAttributes()) {
						Element element = (Element) node;
						NamedNodeMap attributes = element.getAttributes();
						Node idTypedAttribute = null;
						Node requiredAttribute = null;
						boolean hasId = false;
						boolean hasName = false;
						Node shownAttribute = null;

						// try to get content model element
						// declaration
						CMElementDeclaration elementDecl = null;
						ModelQuery mq = ModelQueryUtil.getModelQuery(element.getOwnerDocument());
						if (mq != null) {
							elementDecl = mq.getCMElementDeclaration(element);
						}
						// find an attribute of type (or just named)
						// ID
						if (elementDecl != null) {
							int i = 0;
							while (i < attributes.getLength() && idTypedAttribute == null) {
								Node attr = attributes.item(i);
								String attrName = attr.getNodeName();
								CMAttributeDeclaration attrDecl = (CMAttributeDeclaration) elementDecl.getAttributes().getNamedItem(attrName);
								if (attrDecl != null) {
									if ((attrDecl.getAttrType() != null) && (CMDataType.ID.equals(attrDecl.getAttrType().getDataTypeName()))) {
										idTypedAttribute = attr;
									}
									else if (attrDecl.getUsage() == CMAttributeDeclaration.REQUIRED && requiredAttribute == null) {
										// as a backup, keep tabs on
										// any required
										// attributes
										requiredAttribute = attr;
									}
									else {
										hasId = hasId || attrName.equals("id"); //$NON-NLS-1$
										hasName = hasName || attrName.equals("name"); //$NON-NLS-1$
									}
								}
								++i;
							}
						}

						/*
						 * If no suitable attribute was found, try using a
						 * required attribute, if none, then prefer "id" or
						 * "name", otherwise just use first attribute
						 */
						if (idTypedAttribute != null) {
							shownAttribute = idTypedAttribute;
						}
						else if (requiredAttribute != null) {
							shownAttribute = requiredAttribute;
						}
						else if (hasId) {
							shownAttribute = attributes.getNamedItem("id"); //$NON-NLS-1$
						}
						else if (hasName) {
							shownAttribute = attributes.getNamedItem("name"); //$NON-NLS-1$
						}
						if (shownAttribute == null) {
							shownAttribute = attributes.item(0);
						}

						// display the attribute and value (without quotes)
						String attributeName = shownAttribute.getNodeName();
						if (attributeName != null && attributeName.length() > 0) {
							text.append(" " + attributeName); //$NON-NLS-1$
							String attributeValue = shownAttribute.getNodeValue();
							if (attributeValue != null && attributeValue.length() > 0) {
								text.append("=" + StringUtils.strip(attributeValue)); //$NON-NLS-1$
							}
						}
					}
				}
			}
			return text.toString();
		}
	}

	/**
	 * Toggle action for whether or not to display element's first attribute
	 */
	private class ToggleShowAttributeAction extends PropertyChangeUpdateAction {
		// https://bugs.eclipse.org/bugs/show_bug.cgi?id=88444
		private TreeViewer fTreeViewer;

		public ToggleShowAttributeAction(IPreferenceStore store, String preference, TreeViewer treeViewer) {
			super(XMLUIMessages.XMLContentOutlineConfiguration_0, store, preference, true);
			setToolTipText(getText());
			// images needed
			// setDisabledImageDescriptor(SYNCED_D);
			// (nsd) temporarily re-use Properties view image
			setImageDescriptor(EditorPluginImageHelper.getInstance().getImageDescriptor(EditorPluginImages.IMG_OBJ_PROP_PS));
			fTreeViewer = treeViewer;
			update();
		}

		/*
		 * (non-Javadoc)
		 * 
		 * @see org.eclipse.ui.texteditor.IUpdate#update()
		 */
		public void update() {
			super.update();
			fShowAttributes = isChecked();

			// notify the configuration of the change
			enableShowAttributes(fShowAttributes, fTreeViewer);

			// refresh the outline view
			fTreeViewer.refresh(true);
		}
	}

	private IContentProvider fContentProvider = null;

	private ActionManagerMenuListener fContextMenuFiller = null;

	private ILabelProvider fLabelProvider = null;

	boolean fShowAttributes = false;

	private TransferDragSourceListener[] fTransferDragSourceListeners;
	private TransferDropTargetListener[] fTransferDropTargetListeners;

	/*
	 * Preference key for Show Attributes
	 */
	private final String OUTLINE_SHOW_ATTRIBUTE_PREF = "outline-show-attribute-editor"; //$NON-NLS-1$

	/**
	 * Create new instance of XMLContentOutlineConfiguration
	 */
	public XMLContentOutlineConfiguration() {
		// Must have empty constructor to createExecutableExtension
		super();
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.wst.sse.ui.views.contentoutline.ContentOutlineConfiguration#createMenuContributions(org.eclipse.jface.viewers.TreeViewer)
	 */
	protected IContributionItem[] createMenuContributions(TreeViewer viewer) {
		IContributionItem[] items;
		// https://bugs.eclipse.org/bugs/show_bug.cgi?id=88444
		IContributionItem showAttributeItem = new PropertyChangeUpdateActionContributionItem(new ToggleShowAttributeAction(getPreferenceStore(), OUTLINE_SHOW_ATTRIBUTE_PREF, viewer));
		items = super.createMenuContributions(viewer);
		if (items == null) {
			items = new IContributionItem[]{showAttributeItem};
		}
		else {
			IContributionItem[] combinedItems = new IContributionItem[items.length + 1];
			System.arraycopy(items, 0, combinedItems, 0, items.length);
			combinedItems[items.length] = showAttributeItem;
			items = combinedItems;
		}
		return items;
	}

	/**
	 * Returns the NodeActionManager to use for the given treeViewer.
	 * <p>
	 * Not API. May be removed in the future.
	 * </p>
	 * 
	 * @param treeViewer
	 *            the TreeViewer associated with this configuration
	 * @return a node action manager for use with this tree viewer
	 */
	protected XMLNodeActionManager createNodeActionManager(TreeViewer treeViewer) {
		return new XMLNodeActionManager((IStructuredModel) treeViewer.getInput(), treeViewer);
	}

	/**
	 * Notifies this configuration that the flag that indicates whether or not
	 * to show attribute values in the tree viewer has changed. The tree
	 * viewer is automatically refreshed afterwards to update the labels.
	 * 
	 * Clients should not call this method, but rather should react to it.
	 * 
	 * @param showAttributes
	 *            flag indicating whether or not to show attribute values in
	 *            the tree viewer
	 * @param treeViewer
	 *            the TreeViewer associated with this configuration
	 */
	protected void enableShowAttributes(boolean showAttributes, TreeViewer treeViewer) {
		// nothing by default
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.wst.sse.ui.views.contentoutline.ContentOutlineConfiguration#getContentProvider(org.eclipse.jface.viewers.TreeViewer)
	 */
	public IContentProvider getContentProvider(TreeViewer viewer) {
		if (fContentProvider == null) {
			fContentProvider = new JFaceNodeContentProvider();
		}
		return fContentProvider;
	}

	private Object getFilteredNode(Object object) {
		if (object instanceof Node) {
			Node node = (Node) object;

			// replace attribute node in selection with its parent
			if (node.getNodeType() == Node.ATTRIBUTE_NODE)
				node = ((Attr) node).getOwnerElement();
			// replace TextNode in selection with its parent
			else if (node.getNodeType() == Node.TEXT_NODE)
				node = node.getParentNode();
			return node;
		}
		return object;
	}

	private Object[] getFilteredNodes(Object[] filteredNodes) {
		for (int i = 0; i < filteredNodes.length; i++) {
			filteredNodes[i] = getFilteredNode(filteredNodes[i]);
		}
		return filteredNodes;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.wst.sse.ui.views.contentoutline.ContentOutlineConfiguration#getLabelProvider(org.eclipse.jface.viewers.TreeViewer)
	 */
	public ILabelProvider getLabelProvider(TreeViewer viewer) {
		if (fLabelProvider == null) {
			fLabelProvider = new AttributeShowingLabelProvider();
		}
		return fLabelProvider;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.wst.sse.ui.views.contentoutline.ContentOutlineConfiguration#getMenuListener(org.eclipse.jface.viewers.TreeViewer)
	 */
	public IMenuListener getMenuListener(TreeViewer viewer) {
		if (fContextMenuFiller == null) {
			fContextMenuFiller = new ActionManagerMenuListener(viewer);
		}
		return fContextMenuFiller;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.wst.sse.ui.views.contentoutline.ContentOutlineConfiguration#getPreferenceStore()
	 */
	protected IPreferenceStore getPreferenceStore() {
		return XMLUIPlugin.getDefault().getPreferenceStore();
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.wst.sse.ui.views.contentoutline.ContentOutlineConfiguration#getSelection(org.eclipse.jface.viewers.TreeViewer,
	 *      org.eclipse.jface.viewers.ISelection)
	 */
	public ISelection getSelection(TreeViewer viewer, ISelection selection) {
		ISelection filteredSelection = selection;
		if (selection instanceof IStructuredSelection) {
			Object[] filteredNodes = getFilteredNodes(((IStructuredSelection) selection).toArray());
			filteredSelection = new StructuredSelection(filteredNodes);
		}
		return filteredSelection;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.wst.sse.ui.views.contentoutline.ContentOutlineConfiguration#getTransferDragSourceListeners(org.eclipse.jface.viewers.TreeViewer)
	 */
	public TransferDragSourceListener[] getTransferDragSourceListeners(final TreeViewer treeViewer) {
		if (fTransferDragSourceListeners == null) {
			fTransferDragSourceListeners = new TransferDragSourceListener[]{new TransferDragSourceListener() {

				public void dragFinished(DragSourceEvent event) {
					LocalSelectionTransfer.getTransfer().setSelection(null);
				}

				public void dragSetData(DragSourceEvent event) {
				}

				public void dragStart(DragSourceEvent event) {
					LocalSelectionTransfer.getTransfer().setSelection(treeViewer.getSelection());
				}

				public Transfer getTransfer() {
					return LocalSelectionTransfer.getTransfer();
				}
			}};
		}

		return fTransferDragSourceListeners;
	}
	 
	 /*
		 * (non-Javadoc)
		 * 
		 * @see org.eclipse.wst.sse.ui.views.contentoutline.ContentOutlineConfiguration#getTransferDropTargetListeners(org.eclipse.jface.viewers.TreeViewer)
		 */
	public TransferDropTargetListener[] getTransferDropTargetListeners(final TreeViewer treeViewer) {
		if (fTransferDropTargetListeners == null) {
			fTransferDropTargetListeners = new TransferDropTargetListener[]{new TransferDropTargetListener() {
				public void dragEnter(DropTargetEvent event) {
				}

				public void dragLeave(DropTargetEvent event) {
				}

				public void dragOperationChanged(DropTargetEvent event) {
				}

				public void dragOver(DropTargetEvent event) {
					event.feedback = DND.FEEDBACK_SELECT;
					float feedbackFloat = getHeightInItem(event);
					if (feedbackFloat > 0.75) {
						event.feedback = DND.FEEDBACK_INSERT_AFTER;
					}
					else if (feedbackFloat < 0.25) {
						event.feedback = DND.FEEDBACK_INSERT_BEFORE;
					}
					event.feedback |= DND.FEEDBACK_EXPAND | DND.FEEDBACK_SCROLL;
				}

				public void drop(DropTargetEvent event) {
					if (event.operations != DND.DROP_NONE && LocalSelectionTransfer.getTransfer().getSelection() != null && !LocalSelectionTransfer.getTransfer().getSelection().isEmpty()) {
						IStructuredSelection selection = (IStructuredSelection) LocalSelectionTransfer.getTransfer().getSelection();
						if (selection != null && !selection.isEmpty() && event.item != null && event.item.getData() != null) {
							/*
							 * the command uses these numbers instead of the
							 * feedback constants (even though it converts in
							 * the other direction as well)
							 */
							float feedbackFloat = getHeightInItem(event);

							final DragNodeCommand command = new DragNodeCommand(event.item.getData(), feedbackFloat, event.operations, event.detail, selection.toList(), treeViewer);
							if (command != null && command.canExecute()) {
								SafeRunnable.run(new SafeRunnable() {
									public void run() throws Exception {
										command.execute();
									}
								});
							}
						}
					}
				}

				public void dropAccept(DropTargetEvent event) {
				}

				private float getHeightInItem(DropTargetEvent event) {
					if (event.item == null)
						return .5f;
					if (event.item instanceof TreeItem) {
						TreeItem treeItem = (TreeItem) event.item;
						Control control = treeItem.getParent();
						Point point = control.toControl(new Point(event.x, event.y));
						Rectangle bounds = treeItem.getBounds();
						return (float) (point.y - bounds.y) / (float) bounds.height;
					}
					else if (event.item instanceof TableItem) {
						TableItem tableItem = (TableItem) event.item;
						Control control = tableItem.getParent();
						Point point = control.toControl(new Point(event.x, event.y));
						Rectangle bounds = tableItem.getBounds(0);
						return (float) (point.y - bounds.y) / (float) bounds.height;
					}
					else {
						return 0.0F;
					}
				}

				public Transfer getTransfer() {
					return LocalSelectionTransfer.getTransfer();
				}

				public boolean isEnabled(DropTargetEvent event) {
					return getTransfer().isSupportedType(event.currentDataType);
				}
			}};
		}
		return fTransferDropTargetListeners;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.wst.sse.ui.views.contentoutline.ContentOutlineConfiguration#unconfigure(org.eclipse.jface.viewers.TreeViewer)
	 */
	public void unconfigure(TreeViewer viewer) {
		super.unconfigure(viewer);
		fTransferDragSourceListeners = null;
		fTransferDropTargetListeners = null;
		if (fContextMenuFiller != null) {
			fContextMenuFiller.release();
			fContextMenuFiller = null;
		}
	}
}