package de.lmu.ifi.dbs.elki.visualization.visualizers.parallel.index;

/*This file is part of ELKI:
 Environment for Developing KDD-Applications Supported by Index-Structures

 Copyright (C) 2012
 Ludwig-Maximilians-Universität München
 Lehr- und Forschungseinheit für Datenbanksysteme
 ELKI Development Team

 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/>.
 */

import java.util.ArrayList;
import java.util.Collection;

import org.apache.batik.util.SVGConstants;
import org.w3c.dom.Element;

import de.lmu.ifi.dbs.elki.data.NumberVector;
import de.lmu.ifi.dbs.elki.data.spatial.SpatialUtil;
import de.lmu.ifi.dbs.elki.database.datastore.DataStoreListener;
import de.lmu.ifi.dbs.elki.index.tree.spatial.SpatialEntry;
import de.lmu.ifi.dbs.elki.index.tree.spatial.rstarvariants.AbstractRStarTree;
import de.lmu.ifi.dbs.elki.index.tree.spatial.rstarvariants.AbstractRStarTreeNode;
import de.lmu.ifi.dbs.elki.index.tree.spatial.rstarvariants.rstar.RStarTreeNode;
import de.lmu.ifi.dbs.elki.result.HierarchicalResult;
import de.lmu.ifi.dbs.elki.result.Result;
import de.lmu.ifi.dbs.elki.result.ResultUtil;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizer;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameterization.Parameterization;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameters.Flag;
import de.lmu.ifi.dbs.elki.visualization.VisualizationTask;
import de.lmu.ifi.dbs.elki.visualization.colors.ColorLibrary;
import de.lmu.ifi.dbs.elki.visualization.css.CSSClass;
import de.lmu.ifi.dbs.elki.visualization.projections.ProjectionParallel;
import de.lmu.ifi.dbs.elki.visualization.projector.ParallelPlotProjector;
import de.lmu.ifi.dbs.elki.visualization.style.StyleLibrary;
import de.lmu.ifi.dbs.elki.visualization.svg.SVGPath;
import de.lmu.ifi.dbs.elki.visualization.svg.SVGPlot;
import de.lmu.ifi.dbs.elki.visualization.svg.SVGUtil;
import de.lmu.ifi.dbs.elki.visualization.visualizers.AbstractVisFactory;
import de.lmu.ifi.dbs.elki.visualization.visualizers.Visualization;
import de.lmu.ifi.dbs.elki.visualization.visualizers.parallel.AbstractParallelVisualization;
import de.lmu.ifi.dbs.elki.visualization.visualizers.scatterplot.index.TreeMBRVisualization;

/**
 * Visualize the of an R-Tree based index.
 * 
 * @author Robert Rödler
 * 
 * @apiviz.stereotype factory
 * @apiviz.uses Instance oneway - - «create»
 */
public class RTreeParallelVisualization extends AbstractVisFactory {
  /**
   * Generic tag to indicate the type of element. Used in IDs, CSS-Classes etc.
   */
  public static final String INDEX = "parallelrtree";

  /**
   * A short name characterizing this Visualizer.
   */
  public static final String NAME = "R-Tree Index MBRs";

  /**
   * Settings
   */
  protected Parameterizer settings;

  /**
   * Constructor.
   * 
   * @param settings Settings
   */
  public RTreeParallelVisualization(Parameterizer settings) {
    super();
    this.settings = settings;
  }

  @Override
  public Visualization makeVisualization(VisualizationTask task) {
    return new Instance<RStarTreeNode, SpatialEntry>(task);
  }

  @Override
  public void processNewResult(HierarchicalResult baseResult, Result result) {
    ArrayList<AbstractRStarTree<RStarTreeNode, SpatialEntry>> trees = ResultUtil.filterResults(result, AbstractRStarTree.class);
    for(AbstractRStarTree<RStarTreeNode, SpatialEntry> tree : trees) {
      if(tree instanceof Result) {
        Collection<ParallelPlotProjector<?>> ps = ResultUtil.filterResults(baseResult, ParallelPlotProjector.class);
        for(ParallelPlotProjector<?> p : ps) {
          final VisualizationTask task = new VisualizationTask(NAME, (Result) tree, p.getRelation(), this);
          task.level = VisualizationTask.LEVEL_BACKGROUND + 2;
          baseResult.getHierarchy().add((Result) tree, task);
          baseResult.getHierarchy().add(p, task);
        }
      }
    }
  }

  /**
   * Instance for a particular data set and tree
   * 
   * @author Robert Rödler
   * 
   * @apiviz.has AbstractRStarTree oneway - - visualizes
   * 
   * @param <N> Tree node type
   * @param <E> Tree entry type
   */
  // TODO: listen for tree changes instead of data changes?
  public class Instance<N extends AbstractRStarTreeNode<N, E>, E extends SpatialEntry> extends AbstractParallelVisualization<NumberVector<?>> implements DataStoreListener {
    /**
     * The tree we visualize
     */
    protected AbstractRStarTree<N, E> tree;

    /**
     * Constructor.
     * 
     * @param task Visualization task
     */
    @SuppressWarnings("unchecked")
    public Instance(VisualizationTask task) {
      super(task);
      this.tree = AbstractRStarTree.class.cast(task.getResult());
      context.addDataStoreListener(this);
      context.addResultListener(this);
      incrementalRedraw();
    }

    @Override
    public void destroy() {
      context.removeDataStoreListener(this);
      context.removeResultListener(this);
      super.destroy();
    }

    @Override
    protected void redraw() {
      if(tree != null) {
        addCSSClasses(svgp);
        E root = tree.getRootEntry();
        visualizeRTreeEntry(svgp, layer, proj, tree, root, 0, 0);
      }
    }

    /**
     * Adds the required CSS-Classes
     * 
     * @param svgp SVG-Plot
     */
    private void addCSSClasses(SVGPlot svgp) {
      final StyleLibrary style = context.getStyleResult().getStyleLibrary();
      final ColorLibrary colors = style.getColorSet(StyleLibrary.PLOT);

      for(int i = 0; i < tree.getHeight(); i++) {
        if(!svgp.getCSSClassManager().contains(INDEX + i)) {
          CSSClass cls = new CSSClass(this, INDEX + i);

          // Relative depth of this level. 1.0 = toplevel
          final double relDepth = 1. - (((double) i) / tree.getHeight());
          if(settings.fill) {
            cls.setStatement(SVGConstants.CSS_STROKE_PROPERTY, colors.getColor(i));
            cls.setStatement(SVGConstants.CSS_STROKE_WIDTH_PROPERTY, relDepth * style.getLineWidth(StyleLibrary.PLOT));
            cls.setStatement(SVGConstants.CSS_FILL_PROPERTY, colors.getColor(i));
            cls.setStatement(SVGConstants.CSS_FILL_OPACITY_PROPERTY, 0.2);
          }
          else {
            cls.setStatement(SVGConstants.CSS_STROKE_PROPERTY, colors.getColor(i));
            cls.setStatement(SVGConstants.CSS_STROKE_WIDTH_PROPERTY, relDepth * style.getLineWidth(StyleLibrary.PLOT));
            cls.setStatement(SVGConstants.CSS_FILL_PROPERTY, SVGConstants.CSS_NONE_VALUE);
          }
          cls.setStatement(SVGConstants.CSS_STROKE_LINECAP_PROPERTY, SVGConstants.CSS_ROUND_VALUE);
          cls.setStatement(SVGConstants.CSS_STROKE_LINEJOIN_PROPERTY, SVGConstants.CSS_ROUND_VALUE);
          svgp.addCSSClassOrLogError(cls);
        }
      }
      svgp.updateStyleElement();
    }

    /**
     * Recursively draw the MBR rectangles.
     * 
     * @param svgp SVG Plot
     * @param layer Layer
     * @param proj Projection
     * @param rtree Rtree to visualize
     * @param entry Current entry
     * @param depth Current depth
     */
    private void visualizeRTreeEntry(SVGPlot svgp, Element layer, ProjectionParallel proj, AbstractRStarTree<? extends N, E> rtree, E entry, int depth, int step) {
      final int dim = proj.getVisibleDimensions();
      double[] min = proj.fastProjectDataToRenderSpace(SpatialUtil.getMin(entry));
      double[] max = proj.fastProjectDataToRenderSpace(SpatialUtil.getMax(entry));
      assert (min.length == dim && max.length == dim);
      SVGPath path = new SVGPath();
      for(int i = 0; i < dim; i++) {
        path.drawTo(getVisibleAxisX(i), Math.max(min[i], max[i]));
      }
      for(int i = dim - 1; i >= 0; i--) {
        path.drawTo(getVisibleAxisX(i), Math.min(min[i], max[i]));
      }
      path.close();

      Element intervals = path.makeElement(svgp);

      SVGUtil.addCSSClass(intervals, INDEX + depth);
      layer.appendChild(intervals);

      if(!entry.isLeafEntry()) {
        N node = rtree.getNode(entry);
        for(int i = 0; i < node.getNumEntries(); i++) {
          E child = node.getEntry(i);
          if(!child.isLeafEntry()) {
            visualizeRTreeEntry(svgp, layer, proj, rtree, child, depth + 1, ++step);
          }
        }
      }
    }

  }

  /**
   * Parameterization class.
   * 
   * @author Erich Schubert
   * 
   * @apiviz.exclude
   */
  public static class Parameterizer extends AbstractParameterizer {
    protected boolean fill = true;

    @Override
    protected void makeOptions(Parameterization config) {
      super.makeOptions(config);
      Flag fillF = new Flag(TreeMBRVisualization.Parameterizer.FILL_ID);
      fillF.setDefaultValue(Boolean.TRUE);
      if(config.grab(fillF)) {
        fill = fillF.isTrue();
      }
    }

    @Override
    protected RTreeParallelVisualization makeInstance() {
      return new RTreeParallelVisualization(this);
    }
  }
}