/*
 *  RapidMiner
 *
 *  Copyright (C) 2001-2014 by RapidMiner and the contributors
 *
 *  Complete list of developers available at our web site:
 *
 *       http://rapidminer.com
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Affero General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program 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 Affero General Public License for more details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with this program.  If not, see http://www.gnu.org/licenses/.
 */
package com.rapidminer.gui.graphs;

import java.awt.Dimension;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

import javax.swing.JComponent;
import javax.swing.JLabel;
import javax.swing.JSlider;
import javax.swing.SwingConstants;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;

import org.apache.commons.collections15.Factory;

import com.rapidminer.example.Attribute;
import com.rapidminer.example.Example;
import com.rapidminer.example.ExampleSet;
import com.rapidminer.tools.Tools;
import com.rapidminer.tools.math.similarity.DistanceMeasure;

import edu.uci.ics.jung.graph.Graph;
import edu.uci.ics.jung.graph.UndirectedSparseGraph;
import edu.uci.ics.jung.graph.util.EdgeType;

/**
 * The graph model creator for similarity measurements.
 *
 * @author Ingo Mierswa
 */
public class SimilarityGraphCreator extends GraphCreatorAdaptor {

	private Factory<String> edgeFactory = new Factory<String>() {
		int i = 0;
		public String create() {
			return "E" + i++;
		}
	};

	private JSlider distanceSlider = new JSlider(SwingConstants.HORIZONTAL, 0, 1000, 100) {
		private static final long serialVersionUID = -6931545310805789589L;
		@Override
		public Dimension getMinimumSize() {
			return new Dimension(40, (int)super.getMinimumSize().getHeight());
		}
		@Override
		public Dimension getPreferredSize() {
			return new Dimension(40, (int)super.getPreferredSize().getHeight());
		}
		@Override
		public Dimension getMaximumSize() {
			return new Dimension(40, (int)super.getMaximumSize().getHeight());
		}
	};

	private Graph<String,String> graph;

	private DistanceMeasure measure;

	private ExampleSet exampleSet;

	private Map<String, String> edgeLabelMap = new HashMap<String, String>();

	private Map<String, Double> edgeStrengthMap = new HashMap<String, Double>();

	private DefaultObjectViewer objectViewer;


	public SimilarityGraphCreator(DistanceMeasure measure, ExampleSet exampleSet) {
		this.measure = measure;
		this.exampleSet = exampleSet;
		objectViewer = new DefaultObjectViewer(exampleSet);
	}

	public Graph<String,String> createGraph() {
		graph = new UndirectedSparseGraph<String, String>();

		Attribute id = exampleSet.getAttributes().getId();
		if (id!= null) {
			for (Example example : exampleSet) {
				graph.addVertex(example.getValueAsString(id));
			}
			addEdges();
		}
		return graph;
	}

	@Override
	public String getEdgeName(String id) {
		return edgeLabelMap.get(id);
	}

	@Override
	public String getVertexName(String id) {
		return id;
	}

	@Override
	public String getVertexToolTip(String id) {
		return id;
	}

	/** Returns the label offset. In most case, using -1 is just fine (default offset). 
	 *  Some tree like graphs might prefer to use 0 since they manage the offset themself. */
	@Override
	public int getLabelOffset() {
		return -1;
	}

	@Override
	public int getNumberOfOptionComponents() { 
		return 2;
	}

	@Override
	public JComponent getOptionComponent(final GraphViewer viewer, int index) {
		if (index == 0) {
			return new JLabel("Number of Edges:");
		} else if (index == 1) {
			this.distanceSlider.addChangeListener(new ChangeListener() {
				public void stateChanged(ChangeEvent e) {
					if (!distanceSlider.getValueIsAdjusting()) {
						addEdges();
						viewer.updateLayout();
					}
				}
			});
			return distanceSlider;            
		} else {
			return null;
		}
	}

	private void addEdges() {    	
		// remove old edges if available
		Iterator<String> e = edgeLabelMap.keySet().iterator();
		while (e.hasNext()) {
			graph.removeEdge(e.next());
		}
		edgeLabelMap.clear();

		boolean isDistance = measure.isDistance();
		Attribute id = exampleSet.getAttributes().getId();
		List<SortableEdge> sortableEdges = new LinkedList<SortableEdge>();
		for (int i = 0; i < exampleSet.size(); i++) {
			Example example = exampleSet.getExample(i);
			for (int j = i + 1; j < exampleSet.size(); j++) {
				Example comExample = exampleSet.getExample(j);
				if (isDistance) 
					sortableEdges.add(new SortableEdge(example.getValueAsString(id), comExample.getValueAsString(id), null, measure.calculateDistance(example, comExample), SortableEdge.DIRECTION_INCREASE));
				else
					sortableEdges.add(new SortableEdge(example.getValueAsString(id), comExample.getValueAsString(id), null, measure.calculateSimilarity(example, comExample), SortableEdge.DIRECTION_DECREASE));
			}
		}

		Collections.sort(sortableEdges);

		int numberOfEdges = distanceSlider.getValue();
		int counter = 0;
		double minStrength = Double.POSITIVE_INFINITY;
		double maxStrength = Double.NEGATIVE_INFINITY;
		Map<String,Double> strengthMap = new HashMap<String, Double>();
		for (SortableEdge sortableEdge : sortableEdges) {
			if (counter > numberOfEdges)
				break;

			String idString = edgeFactory.create();
			graph.addEdge(idString, sortableEdge.getFirstVertex(), sortableEdge.getSecondVertex(), EdgeType.UNDIRECTED);
			edgeLabelMap.put(idString, Tools.formatIntegerIfPossible(sortableEdge.getEdgeValue()));

			double strength = sortableEdge.getEdgeValue();

			minStrength = Math.min(minStrength, strength);
			maxStrength = Math.max(maxStrength, strength);

			strengthMap.put(idString, strength);

			counter++;
		}

		for (Entry<String, Double> entry : strengthMap.entrySet()) {
			edgeStrengthMap.put(entry.getKey(), (entry.getValue() - minStrength) / (maxStrength - minStrength));
		}
	}

	/** Returns false. */
	@Override
	public boolean showEdgeLabelsDefault() {
		return false;
	}

	/** Returns false. */
	@Override
	public boolean showVertexLabelsDefault() {
		return false;
	}

	@Override
	public double getEdgeStrength(String id) {
		Double value = edgeStrengthMap.get(id);
		if (value == null) {
			return 1.0d;
		} else {
			if (Double.isNaN(value))
				return 1.0d;
			else
				return value;
		}
	}

	/** Returns the shape of the edges. */
	@Override
	public int getEdgeShape() {
		return EDGE_SHAPE_QUAD_CURVE;
	}

	@Override
	public Object getObject(String id) {
		return id;
	}

	@Override
	public GraphObjectViewer getObjectViewer() {
		return objectViewer;
	}
}