package org.activityinfo.server.report.renderer.image;

/*
 * #%L
 * ActivityInfo Server
 * %%
 * Copyright (C) 2009 - 2013 UNICEF
 * %%
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU 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 General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public 
 * License along with this program.  If not, see
 * <http://www.gnu.org/licenses/gpl-3.0.html>.
 * #L%
 */

import com.google.code.appengine.awt.Graphics2D;
import org.activityinfo.legacy.shared.reports.content.PieChartLegend;
import org.activityinfo.legacy.shared.reports.content.PieMapMarker;
import org.activityinfo.legacy.shared.reports.model.layers.PiechartMapLayer;

public class PieChartLegendRenderer {

    private static final int PADDING = 2;

    private int width;
    private int height;

    private PiechartMapLayer layer;

    public PieChartLegendRenderer(PieChartLegend legend) {
        this.layer = legend.getDefinition();

        this.width = this.height = PADDING + (layer.getMaxRadius() * 2) + PADDING;
    }

    public ItextGraphic createImage(ImageCreator creator) {
        ItextGraphic result = creator.create(width, height);
        drawSymbol(result.getGraphics());

        return result;
    }

    private void drawSymbol(Graphics2D g2d) {
        PieMapMarker marker = new PieMapMarker();
        marker.setRadius(layer.getMaxRadius());
        marker.setX(PADDING + layer.getMaxRadius());
        marker.setY(PADDING + layer.getMaxRadius());

        double values[] = calculateNiceLookingValues(layer.getSlices().size());
        int nextValue = 0;

        for (PiechartMapLayer.Slice slice : layer.getSlices()) {
            PieMapMarker.SliceValue sliceValue = new PieMapMarker.SliceValue();
            sliceValue.setColor(slice.getColor());
            sliceValue.setValue(values[nextValue++]);

            marker.getSlices().add(sliceValue);
        }

        ImageMapRenderer.drawPieMarker(g2d, marker);
    }

    private double[] calculateNiceLookingValues(int count) {
        if (count == 1) {
            return new double[]{100};
        } else if (count == 2) {
            return new double[]{75, 25};
        } else {
            double values[] = new double[count];
            double value = 1;
            for (int i = 0; i != values.length; ++i) {
                values[i] = value;
                value *= 1.5;
            }
            return values;
        }
    }

}