/*
 * Copyright (C) 2008-2015 by Holger Arndt
 *
 * This file is part of the Universal Java Matrix Package (UJMP).
 * See the NOTICE file distributed with this work for additional
 * information regarding copyright ownership and licensing.
 *
 * UJMP is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * UJMP 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with UJMP; if not, write to the
 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
 * Boston, MA  02110-1301  USA
 */

package org.ujmp.core.graphmatrix;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.ujmp.core.genericmatrix.stub.AbstractSparseGenericMatrix2D;
import org.ujmp.core.util.MathUtil;

public abstract class AbstractGraphMatrix extends AbstractSparseGenericMatrix2D implements
		GraphMatrix {

	public AbstractGraphMatrix() {
		super(0, 0);
	}

	private static final long serialVersionUID = -4939918585100574441L;

	public boolean containsCoordinates(long... coordinates) {
		return isConnected(coordinates[ROW], coordinates[COLUMN]);
	}

	public boolean isConnected(N node1, N node2) {
		long index1 = getIndexOfNode(node1);
		long index2 = getIndexOfNode(node2);
		return isConnected(index1, index2);
	}

	public List getParents(long index) {
		List indices = getParentIndices(index);
		List objects = new ArrayList(indices.size());
		for (int i = 0; i < indices.size(); i++) {
			objects.add(getNode(indices.get(i)));
		}
		return objects;
	}

	public List getEdgesToParents(N node) {
		long index = getIndexOfNode(node);
		List parentIndices = getParentIndices(index);
		List edgeList = new ArrayList(parentIndices.size());
		for (long parentIndex : parentIndices) {
			edgeList.add(getEdge(parentIndex, index));
		}
		return edgeList;
	}

	public List getEdgesToChildren(N node) {
		long index = getIndexOfNode(node);
		List childIndices = getChildIndices(index);
		List edgeList = new ArrayList(childIndices.size());
		for (long childIndex : childIndices) {
			edgeList.add(getEdge(index, childIndex));
		}
		return edgeList;
	}

	public List getParents(N node) {
		List indices = getParentIndices(node);
		List objects = new ArrayList(indices.size());
		for (int i = 0; i < indices.size(); i++) {
			objects.add(getNode(indices.get(i)));
		}
		return objects;
	}

	public List getChildren(long index) {
		List indices = getChildIndices(index);
		List objects = new ArrayList(indices.size());
		for (int i = 0; i < indices.size(); i++) {
			objects.add(getNode(indices.get(i)));
		}
		return objects;
	}

	public List getParentIndices(N node) {
		long index = getIndexOfNode(node);
		return getParentIndices(index);
	}

	public E getEdge(N node1, N node2) {
		long index1 = getIndexOfNode(node1);
		long index2 = getIndexOfNode(node2);
		return getEdge(index1, index2);
	}

	public int getDegree(N node) {
		return getParentCount(node) + getChildCount(node);
	}

	public int getDegree(long nodeIndex) {
		return getParentCount(nodeIndex) + getChildCount(nodeIndex);
	}

	public int getChildCount(N node) {
		return getChildCount(getIndexOfNode(node));
	}

	public int getParentCount(N node) {
		long index = getIndexOfNode(node);
		return getParentCount(index);
	}

	public List getChildIndices(N node) {
		long index = getIndexOfNode(node);
		return getChildIndices(index);
	}

	public List getChildren(N node) {
		List indices = getChildIndices(node);
		List objects = new ArrayList(indices.size());
		for (int i = 0; i < indices.size(); i++) {
			objects.add(getNode(indices.get(i)));
		}
		return objects;
	}

	public Iterable availableCoordinates() {
		Iterable iterable = new Iterable() {

			public Iterator iterator() {
				Iterator iterator = new Iterator() {

					Iterator parents = getNodeList().iterator();
					N parent = parents.next();
					long parentIndex = getIndexOfNode(parent);
					Iterator children = getChildren(parent).iterator();
					long[] current = null;

					public boolean hasNext() {
						if (current != null) {
							return true;
						}

						while (!children.hasNext() && parents.hasNext()) {
							parent = parents.next();
							parentIndex = getIndexOfNode(parent);
							children = getChildren(parent).iterator();
						}

						if (children.hasNext()) {
							current = new long[] { parentIndex, getIndexOfNode(children.next()) };
							return true;
						} else {
							return false;
						}
					}

					public long[] next() {
						long[] tmp = current;
						current = null;
						return tmp;
					}

					public void remove() {
						throw new UnsupportedOperationException("remove not allowed");
					}
				};
				return iterator;
			}
		};
		return iterable;
	}

	public final long[] getSize() {
		size[ROW] = getNodeCount();
		size[COLUMN] = getNodeCount();
		return size;
	}

	public final E getObject(long row, long column) {
		return getEdge(row, column);
	}

	public final E getObject(int row, int column) {
		return getEdge(row, column);
	}

	public final long getValueCount() {
		return getEdgeCount();
	}

	public final void setObject(E value, long row, long column) {
		setEdge(value, row, column);
	}

	public final void setObject(E value, int row, int column) {
		setEdge(value, row, column);
	}

	public final boolean isConnected(long node1, long node2) {
		return MathUtil.getBoolean(getObject(node1, node2));
	}

	public final long getIndexOfNode(N o) {
		return getNodeList().indexOf(o);
	}

}