Copyright (c) 2000, 2017 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
    IBM Corporation - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2000, 2017 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.team.core.synchronize;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.eclipse.core.resources.IContainer;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.IWorkspaceRoot;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Path;
import org.eclipse.team.internal.core.Messages;
import org.eclipse.team.internal.core.TeamPlugin;
import org.eclipse.team.internal.core.subscribers.SyncInfoTreeChangeEvent;

Provides addition API for accessing the SyncInfo in the set through
their resource's hierarchical relationships.

Events fired from a SyncInfoTree will be instances of ISyncInfoTreeChangeEvent.

See Also:
SyncInfoSet
Since:
3.0/**
 * Provides addition API for accessing the <code>SyncInfo</code> in the set through
 * their resource's hierarchical relationships.
 * <p>
 * Events fired from a <code>SyncInfoTree</code> will be instances of <code>ISyncInfoTreeChangeEvent</code>.
 * </p>
 * @see SyncInfoSet
 * @since 3.0
 */
public class SyncInfoTree extends SyncInfoSet {

	protected Map<IPath, Set<IResource>> parents = Collections.synchronizedMap(new HashMap<>());

	
Create an empty sync info tree.
/**
	 * Create an empty sync info tree.
	 */
	public SyncInfoTree() {
		super();
	}

	
Create a sync info tree containing the given sync info elements.
Params:
infos – the sync info elements/**
	 * Create a sync info tree containing the given sync info elements.
	 *
	 * @param infos the sync info elements
	 */
	public SyncInfoTree(SyncInfo[] infos) {
		super(infos);
		for (SyncInfo info : infos) {
			IResource local = info.getLocal();
			addToParents(local, local);
		}
	}

	
Return whether the given resource has any children in the sync set. The children
could be either out-of-sync resources that are contained by the set or containers
that are ancestors of out-of-sync resources contained by the set.
Params:
resource – the resource to check for children.
Returns:
true if the resource has children in the set./**
	 * Return whether the given resource has any children in the sync set. The children
	 * could be either out-of-sync resources that are contained by the set or containers
	 * that are ancestors of out-of-sync resources contained by the set.
	 *
	 * @param resource the resource to check for children.
	 * @return <code>true</code> if the resource has children in the set.
	 */
	public synchronized boolean hasMembers(IResource resource) {
		if (resource.getType() == IResource.FILE) return false;
		IContainer parent = (IContainer)resource;
		if (parent.getType() == IResource.ROOT) return !isEmpty();
		IPath path = parent.getFullPath();
		Set allDescendants = parents.get(path);
		return (allDescendants != null && !allDescendants.isEmpty());
	}

	
Return the SyncInfo for each out-of-sync resource in the subtree
rooted at the given resource to the depth specified. The depth is one of:

IResource.DEPTH_ZERO: the resource only,
IResource.DEPTH_ONE: the resource or its direct children,
IResource.DEPTH_INFINITE: the resource and all of it's
descendants.

If the given resource is out of sync, it will be included in the result.

The default implementation makes use of getSyncInfo(IResource),
members(IResource) and getSyncInfos() to provide
the varying depths. Subclasses may override to optimize.

Params:
resource – the root of the resource subtree
depth –    the depth of the subtree
Returns:
the SyncInfo for any out-of-sync resources/**
	 * Return the <code>SyncInfo</code> for each out-of-sync resource in the subtree
	 * rooted at the given resource to the depth specified. The depth is one of:
	 * <ul>
	 * <li><code>IResource.DEPTH_ZERO</code>: the resource only,
	 * <li><code>IResource.DEPTH_ONE</code>: the resource or its direct children,
	 * <li><code>IResource.DEPTH_INFINITE</code>: the resource and all of it's
	 * descendants.
	 * </ul>
	 * If the given resource is out of sync, it will be included in the result.
	 * <p>
	 * The default implementation makes use of <code>getSyncInfo(IResource)</code>,
	 * <code>members(IResource)</code> and <code>getSyncInfos()</code> to provide
	 * the varying depths. Subclasses may override to optimize.
	 * </p>
	 *
	 * @param resource the root of the resource subtree
	 * @param depth    the depth of the subtree
	 * @return the <code>SyncInfo</code> for any out-of-sync resources
	 */
	public synchronized SyncInfo[] getSyncInfos(IResource resource, int depth) {
		if (depth == IResource.DEPTH_ZERO || resource.getType() == IResource.FILE) {
			SyncInfo info = getSyncInfo(resource);
			if (info == null) {
				return new SyncInfo[0];
			} else {
				return new SyncInfo[] { info };
			}
		}
		if (depth == IResource.DEPTH_ONE) {
			List<SyncInfo> result = new ArrayList<>();
			SyncInfo info = getSyncInfo(resource);
			if (info != null) {
				result.add(info);
			}
			IResource[] members = members(resource);
			for (IResource member : members) {
				info = getSyncInfo(member);
				if (info != null) {
					result.add(info);
				}
			}
			return result.toArray(new SyncInfo[result.size()]);
		}
		// if it's the root then return all out of sync resources.
		if(resource.getType() == IResource.ROOT) {
			return getSyncInfos();
		}
		// for folders return all children deep.
		return internalGetDeepSyncInfo((IContainer)resource);
	}

	/*
	 * Return the <code>SyncInfo</code> for all out-of-sync resources in the
	 * set that are at or below the given resource in the resource hierarchy.
	 * @param resource the root resource
	 * @return the <code>SyncInfo</code> for all out-of-sync resources at or below the given resource
	 */
	private synchronized SyncInfo[] internalGetDeepSyncInfo(IContainer resource) {
		List<SyncInfo> infos = new ArrayList<>();
		IResource[] children = internalGetOutOfSyncDescendants(resource);
		for (IResource child : children) {
			SyncInfo info = getSyncInfo(child);
			if(info != null) {
				infos.add(info);
			} else {
				TeamPlugin.log(IStatus.INFO, Messages.SyncInfoTree_0 + child.getFullPath(), null);
			}
		}
		return infos.toArray(new SyncInfo[infos.size()]);
	}

	@Override
	protected SyncInfoSetChangeEvent createEmptyChangeEvent() {
		return new SyncInfoTreeChangeEvent(this);
	}

	@Override
	public void add(SyncInfo info) {
		try {
			beginInput();
			boolean alreadyExists = getSyncInfo(info.getLocal()) != null;
			super.add(info);
			if(! alreadyExists) {
				IResource local = info.getLocal();
				addToParents(local, local);
			}
		} finally {
			endInput(null);
		}
	}

	@Override
	public void remove(IResource resource) {
		try {
			beginInput();
			super.remove(resource);
			removeFromParents(resource, resource);
		} finally {
			endInput(null);
		}

	}

	@Override
	public void clear() {
		try {
			beginInput();
			super.clear();
			synchronized(this) {
				parents.clear();
			}
		} finally {
			endInput(null);
		}
	}

	private synchronized boolean addToParents(IResource resource, IResource parent) {
		if (parent.getType() == IResource.ROOT) {
			return false;
		}
		// this flag is used to indicate if the parent was previously in the set
		boolean addedParent = false;
		if (parent.getType() == IResource.FILE) {
			// the file is new
			addedParent = true;
		} else {
			Set<IResource> children = parents.get(parent.getFullPath());
			if (children == null) {
				children = new HashSet<>();
				parents.put(parent.getFullPath(), children);
				// this is a new folder in the sync set
				addedParent = true;
			}
			children.add(resource);
		}
		// if the parent already existed and the resource is new, record it
		if (!addToParents(resource, parent.getParent()) && addedParent) {
			internalAddedSubtreeRoot(parent);
		}
		return addedParent;
	}

	private synchronized boolean removeFromParents(IResource resource, IResource parent) {
		if (parent.getType() == IResource.ROOT) {
			return false;
		}
		// this flag is used to indicate if the parent was removed from the set
		boolean removedParent = false;
		if (parent.getType() == IResource.FILE) {
			// the file will be removed
			removedParent = true;
		} else {
			Set<IResource> children = parents.get(parent.getFullPath());
			if (children != null) {
				children.remove(resource);
				if (children.isEmpty()) {
					parents.remove(parent.getFullPath());
					removedParent = true;
				}
			}
		}
		//	if the parent wasn't removed and the resource was, record it
		if (!removeFromParents(resource, parent.getParent()) && removedParent) {
			internalRemovedSubtreeRoot(parent);
		}
		return removedParent;
	}

	private void internalAddedSubtreeRoot(IResource parent) {
		((SyncInfoTreeChangeEvent)getChangeEvent()).addedSubtreeRoot(parent);
	}

	private void internalRemovedSubtreeRoot(IResource parent) {
		((SyncInfoTreeChangeEvent)getChangeEvent()).removedSubtreeRoot(parent);
	}

	
Remove from this set the SyncInfo for the given resource and any
of its descendants within the specified depth. The depth is one of:

IResource.DEPTH_ZERO: the resource only,
IResource.DEPTH_ONE: the resource or its direct children,
IResource.DEPTH_INFINITE: the resource and all of it's
descendants.

Params:
resource – the root of the resource subtree
depth –    the depth of the subtree/**
	 * Remove from this set the <code>SyncInfo</code> for the given resource and any
	 * of its descendants within the specified depth. The depth is one of:
	 * <ul>
	 * <li><code>IResource.DEPTH_ZERO</code>: the resource only,
	 * <li><code>IResource.DEPTH_ONE</code>: the resource or its direct children,
	 * <li><code>IResource.DEPTH_INFINITE</code>: the resource and all of it's
	 * descendants.
	 * </ul>
	 * 
	 * @param resource the root of the resource subtree
	 * @param depth    the depth of the subtree
	 */
	public void remove(IResource resource, int depth) {
		try {
			beginInput();
			if (getSyncInfo(resource) != null) {
				remove(resource);
			}
			if (depth == IResource.DEPTH_ZERO || resource.getType() == IResource.FILE) return;
			if (depth == IResource.DEPTH_ONE) {
				IResource[] members = members(resource);
				for (IResource member : members) {
					if (getSyncInfo(member) != null) {
						remove(member);
					}
				}
			} else if (depth == IResource.DEPTH_INFINITE) {
				IResource [] toRemove = internalGetOutOfSyncDescendants((IContainer)resource);
				for (IResource t : toRemove) {
					remove(t);
				}
			}
		} finally {
			endInput(null);
		}
	}

	
This is an internal method and is not intended to be invoked or
overridden by clients.
/**
	 * This is an internal method and is not intended to be invoked or
	 * overridden by clients.
	 */
	protected synchronized IResource[] internalGetOutOfSyncDescendants(IContainer resource) {
		// The parent map contains a set of all out-of-sync children
		Set<IResource> allChildren = parents.get(resource.getFullPath());
		if (allChildren == null) return new IResource[0];
		return allChildren.toArray(new IResource[allChildren.size()]);
	}

	private synchronized IResource[] internalMembers(IWorkspaceRoot root) {
		Set possibleChildren = parents.keySet();
		Set<IResource> children = new HashSet<>();
		for (Iterator it = possibleChildren.iterator(); it.hasNext();) {
			Object next = it.next();
			IResource element = root.findMember((IPath)next);
			if (element != null) {
				children.add(element.getProject());
			}
		}
		return children.toArray(new IResource[children.size()]);
	}

	
Return the immediate children of the given resource who are either out-of-sync
or contain out-of-sync resources.
Params:
resource – the parent resource
Returns:
the children of the resource that are either out-of-sync or are ancestors of
out-of-sync resources contained in the set/**
	 * Return the immediate children of the given resource who are either out-of-sync
	 * or contain out-of-sync resources.
	 *
	 * @param resource the parent resource
	 * @return the children of the resource that are either out-of-sync or are ancestors of
	 * out-of-sync resources contained in the set
	 */
	public synchronized IResource[] members(IResource resource) {
		if (resource.getType() == IResource.FILE) return new IResource[0];
		IContainer parent = (IContainer)resource;
		if (parent.getType() == IResource.ROOT) return internalMembers((IWorkspaceRoot)parent);
		// OPTIMIZE: could be optimized so that we don't traverse all the deep
		// children to find the immediate ones.
		Set<IResource> children = new HashSet<>();
		IPath path = parent.getFullPath();
		Set possibleChildren = parents.get(path);
		if(possibleChildren != null) {
			for (Iterator it = possibleChildren.iterator(); it.hasNext();) {
				Object next = it.next();
				IResource element = (IResource)next;
				IPath childPath = element.getFullPath();
				IResource modelObject = null;
				if(childPath.segmentCount() == (path.segmentCount() +  1)) {
					modelObject = element;

				} else if (childPath.segmentCount() > path.segmentCount()) {
					IContainer childFolder = parent.getFolder(new Path(null, childPath.segment(path.segmentCount())));
					modelObject = childFolder;
				}
				if (modelObject != null) {
					children.add(modelObject);
				}
			}
		}
		return children.toArray(new IResource[children.size()]);
	}

}