/*******************************************************************************
 * Copyright (c) 2007 Red Hat, Inc.
 * Distributed under license by Red Hat, Inc. All rights reserved.
 * This program is 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:
 *     Red Hat, Inc. - initial API and implementation
 ******************************************************************************/
package org.jboss.ide.eclipse.archives.core.model.internal;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Properties;

import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.IPath;
import org.jboss.ide.eclipse.archives.core.ArchivesCore;
import org.jboss.ide.eclipse.archives.core.ArchivesCoreMessages;
import org.jboss.ide.eclipse.archives.core.model.ArchivesModelException;
import org.jboss.ide.eclipse.archives.core.model.IArchive;
import org.jboss.ide.eclipse.archives.core.model.IArchiveModelRootNode;
import org.jboss.ide.eclipse.archives.core.model.IArchiveNode;
import org.jboss.ide.eclipse.archives.core.model.IArchiveNodeDelta;
import org.jboss.ide.eclipse.archives.core.model.IArchiveNodeVisitor;
import org.jboss.ide.eclipse.archives.core.model.internal.ArchiveNodeDeltaImpl.NodeDelta;
import org.jboss.ide.eclipse.archives.core.model.internal.xb.XbPackageNode;
import org.jboss.ide.eclipse.archives.core.model.internal.xb.XbPackageNodeWithProperties;

/**
 * Abstract superclass implementation for archive node types
 * @author rob.stryker <rob.stryker@redhat.com>
 *
 */
public abstract class ArchiveNodeImpl implements IArchiveNode {

	protected XbPackageNodeWithProperties nodeDelegate;
	protected IArchiveNode parent;
	protected ArrayList<ArchiveNodeImpl> children;

	// cached data for deltas
	private HashMap<String, NodeDelta> attributeChanges;
	public synchronized HashMap<String, NodeDelta> getAttributeChanges() {
		return (HashMap<String, NodeDelta>)attributeChanges.clone();
	}

	public synchronized HashMap<String, NodeDelta> getPropertyChanges() {
		return (HashMap<String, NodeDelta>)propertyChanges.clone();
	}

	public synchronized HashMap<IArchiveNode, Integer> getChildChanges() {
		return (HashMap<IArchiveNode, Integer>)childChanges.clone();
	}


	private HashMap<String, NodeDelta> propertyChanges;
	private HashMap<IArchiveNode, Integer> childChanges;


	public ArchiveNodeImpl (XbPackageNodeWithProperties delegate) {
		nodeDelegate = delegate;
		children = new ArrayList<ArchiveNodeImpl>();

		// for deltas
		attributeChanges = new HashMap<String, NodeDelta>();
		propertyChanges = new HashMap<String, NodeDelta>();
		childChanges = new HashMap<IArchiveNode, Integer>();
	}

	public XbPackageNode getNodeDelegate() {
		return nodeDelegate;
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#getRoot()
	 */
	public IArchiveNode getRoot() {
		return parent == null ? this : parent.getRoot();
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#getModel()
	 */
	public IArchiveModelRootNode getModelRootNode() {
		Object root = getRoot();
		return root instanceof IArchiveModelRootNode ? (IArchiveModelRootNode)root : null;
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#getDescriptorVersion()
	 */
	public double getDescriptorVersion() {
		IArchiveModelRootNode root = getModelRootNode();
		return root != null ? root.getDescriptorVersion() :
			IArchiveModelRootNode.DESCRIPTOR_VERSION_1_2;
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#getRootArchive()
	 */
	public IArchive getRootArchive() {
		IArchiveNode parent = this.parent;
		IArchive topArchives = null;

		if( getNodeType() == IArchiveNode.TYPE_ARCHIVE ) topArchives = (IArchive)this;
		while( parent != null ) {
			if( parent.getNodeType() == IArchiveNode.TYPE_ARCHIVE )
				topArchives = (IArchive)parent;
			parent = parent.getParent();
		}
		return topArchives;
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#getAllChildren()
	 */
	public IArchiveNode[] getAllChildren () {
		return children.toArray(new IArchiveNode[children.size()]);
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#getChildren(int)
	 */
	public IArchiveNode[] getChildren(int type) {
		ArrayList<IArchiveNode> typedChildren = new ArrayList<IArchiveNode>();
		for (Iterator<ArchiveNodeImpl> iter = children.iterator(); iter.hasNext(); ) {
			IArchiveNode child = iter.next();
			if (child.getNodeType() == type) {
				typedChildren.add(child);
			}
		}

		return typedChildren.toArray(new IArchiveNode[typedChildren.size()]);
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#hasChildren()
	 */
	public boolean hasChildren () {
		return nodeDelegate.hasChildren();
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#hasChild(org.jboss.ide.eclipse.archives.core.model.IArchiveNode)
	 */
	public boolean hasChild (IArchiveNode child) {
		ArchiveNodeImpl childImpl = (ArchiveNodeImpl)child;
		return nodeDelegate.getAllChildren().contains(childImpl.nodeDelegate);
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#getParent()
	 */
	public IArchiveNode getParent() {
		return parent;
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#setParent(org.jboss.ide.eclipse.archives.core.model.IArchiveNode)
	 */
	public void setParent (IArchiveNode parent) {
		if( getParent() != null && parent != getParent()) {
			getParent().removeChild(this);
		}

		this.parent = parent;
		nodeDelegate.setParent(parent == null ? null :
			((ArchiveNodeImpl)parent).getNodeDelegate());
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#getProject()
	 */
	public IPath getProjectPath() {
		IArchiveModelRootNode root = getModelRootNode();
		return root == null ? null : root.getProjectPath();
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#getProjectName()
	 */
	public String getProjectName() {
		IPath path = getProjectPath();
		return ArchivesCore.getInstance().getVFS().getProjectName(path);
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#getProperty(java.lang.String)
	 */
	public String getProperty(String property) {
		return getProperties().getProperty(property);
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#setProperty(java.lang.String, java.lang.String)
	 */
	public void setProperty(String property, String value) {
		if( property == null ) return;
		propertyChanged(property, getProperty(property), value);
		if( value == null ) {
			getProperties().remove(property);
		} else {
			getProperties().setProperty(property, value);
		}
	}

	/**
	 * @return Get the properties for this object
	 */
	protected Properties getProperties() {
		return nodeDelegate.getProperties().getProperties();
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#accept(org.jboss.ide.eclipse.archives.core.model.IArchiveNodeVisitor)
	 */
	public boolean accept(IArchiveNodeVisitor visitor) {
		return accept(visitor, false);
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#accept(org.jboss.ide.eclipse.archives.core.model.IArchiveNodeVisitor, boolean)
	 */
	public boolean accept(IArchiveNodeVisitor visitor, boolean depthFirst) {
		IArchiveNode children[] = getAllChildren();
		boolean keepGoing = true;

		if (!depthFirst)
			keepGoing = visitor.visit(this);

		if (keepGoing) {
			for (int i = 0; i < children.length; i++) {
				if (keepGoing) {
					keepGoing = children[i].accept(visitor, depthFirst);
				}
			}
		}

		if (depthFirst && keepGoing)
			keepGoing = visitor.visit(this);

		return keepGoing;
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#addChild(org.jboss.ide.eclipse.archives.core.model.IArchiveNode)
	 */
	public final void addChild(IArchiveNode node) throws ArchivesModelException {
		addChild(node, true);
	}

	/**
	 * Add a child with the option to skip adding in the delegate
	 * @param child
	 * @param addInDelegate
	 */
	public synchronized final void addChild(IArchiveNode child, boolean addInDelegate) throws ArchivesModelException {
		Assert.isNotNull(child);
		ArchiveNodeImpl childImpl = (ArchiveNodeImpl) child;
		children.add(childImpl);
		childImpl.setParent(this);
		if( addInDelegate )
			nodeDelegate.addChild(childImpl.nodeDelegate);
		childChanges(child, IArchiveNodeDelta.CHILD_ADDED);
		if( !validateModel()) {
			removeChild(child);
			throw new ArchivesModelException(ArchivesCore.bind(ArchivesCoreMessages.ErrorAddChildNode, child.toString()));
		}
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#validateModel()
	 */
	public boolean validateModel() {
		IArchiveNode[] kids = getAllChildren();
		for( int i = 0; i < kids.length; i++ )
			if( !kids[i].validateModel() )
				return false;
		return true;
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#canBuild()
	 */
	public boolean canBuild() {
		IArchiveNode[] kids = getAllChildren();
		for( int i = 0; i < kids.length; i++ )
			if( !kids[i].canBuild() )
				return false;
		return true;
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#removeChild(org.jboss.ide.eclipse.archives.core.model.IArchiveNode)
	 */
	public synchronized void removeChild(IArchiveNode node) {
		Assert.isNotNull(node);
		ArchiveNodeImpl impl = (ArchiveNodeImpl) node;
		boolean removed = false;
		if (nodeDelegate.getAllChildren().contains(impl.nodeDelegate)) {
			nodeDelegate.removeChild(impl.nodeDelegate);
			removed = true;
		}

		if (children.contains(node)) {
			children.remove(node);
			removed = true;
		}
		if( removed )
			childChanges(node, IArchiveNodeDelta.CHILD_REMOVED);
	}

	/**
	 * An attribute has changed. Save the change so it can be represented in a delta
	 */
	protected synchronized void attributeChanged(String key, Object beforeValue, Object afterValue) {
		int kind = IArchiveNodeDelta.ATTRIBUTE_CHANGED;

		// short circuit if no change has REALLY occurred
		if( beforeValue != null && beforeValue.equals(afterValue)) return;

		if( attributeChanges.containsKey(key)) {
			Object original = attributeChanges.get(key).getBefore();
			if( original == null && afterValue == null )
				attributeChanges.remove(key);
			else if( original == null )
				attributeChanges.put(key, new NodeDelta(original, afterValue, kind));
			else if( original.equals(afterValue))
				// value was changed from x to y, then back to x. Therefore, no change
				attributeChanges.remove(key);
			else
				// value was changed from x to y to z.
				// Before should remain x, after should become z
				attributeChanges.put(key, new NodeDelta(original, afterValue, kind));
		} else {
			// added
			attributeChanges.put(key, new NodeDelta(beforeValue, afterValue, kind));
		}
	}

	/**
	 * A property has changed. Save the change so it can be represented in a delta
	 */
	protected synchronized void propertyChanged(String key, Object beforeValue, Object afterValue) {
		// short circuit if no change has REALLY occurred
		if( beforeValue != null && beforeValue.equals(afterValue)) return;


		if( propertyChanges.containsKey(key)) {
			// element has already been added, removed, or changed since last save
			Object original = propertyChanges.get(key).getBefore();
			if( original == null && afterValue == null )
				propertyChanges.remove(key);
			else if( original == null )
				propertyChanges.put(key, new NodeDelta(original, afterValue, IArchiveNodeDelta.PROPERTY_ADDED));
			else if( original.equals(afterValue))
				// value was changed from x to y, then back to x. Therefore, no change
				propertyChanges.remove(key);
			else if( afterValue == null ) {
				// changed from x to y to null, so removed
				propertyChanges.put(key, new NodeDelta(original, afterValue, IArchiveNodeDelta.PROPERTY_REMOVED));
			} else {
				// changed from x to y to z, so changed
				propertyChanges.put(key, new NodeDelta(original, afterValue, IArchiveNodeDelta.PROPERTY_CHANGED));
			}
		} else {
			int kind;
			if( beforeValue == null ) kind = IArchiveNodeDelta.PROPERTY_ADDED;
			else if( afterValue == null ) kind = IArchiveNodeDelta.PROPERTY_REMOVED;
			else kind = IArchiveNodeDelta.PROPERTY_CHANGED;
			propertyChanges.put(key, new NodeDelta(beforeValue, afterValue, kind));
		}
	}

	/**
	 * A child has changed. Save the change
	 * @param node
	 * @param changeType
	 */
	protected synchronized void childChanges(IArchiveNode node, int changeType) {
		if( childChanges.containsKey(node)) {
			int lastChange = childChanges.get(node).intValue();
			if( lastChange == IArchiveNodeDelta.CHILD_ADDED && changeType == IArchiveNodeDelta.CHILD_REMOVED) {
				childChanges.remove(node);
			} else if( lastChange == IArchiveNodeDelta.CHILD_REMOVED && changeType == IArchiveNodeDelta.CHILD_ADDED) {
				childChanges.remove(node);
			}
		} else {
			childChanges.put(node, new Integer(changeType));
		}
	}

	/*
	 * (non-Javadoc)
	 * @see org.jboss.ide.eclipse.archives.core.model.IArchiveNode#getDelta()
	 */
	public IArchiveNodeDelta getDelta() {
		return new ArchiveNodeDeltaImpl(null, this, getAttributeChanges(), 
				getPropertyChanges(), getChildChanges());
	}

	
	/**
	 *  Forget all past state
	 */
	public synchronized void clearDelta() {
		attributeChanges.clear();
		propertyChanges.clear();
		childChanges.clear();

		// clear children recursively
		IArchiveNode[] children = getAllChildren();
		for( int i = 0; i < children.length; i++ )
			((ArchiveNodeImpl)children[i]).clearDelta();
	}
}
