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.Color;
import com.google.code.appengine.awt.Font;
import com.google.code.appengine.awt.Graphics2D;
import com.google.code.appengine.awt.font.LineMetrics;
import com.google.code.appengine.awt.geom.Rectangle2D;
import org.activityinfo.legacy.shared.reports.content.BubbleLayerLegend;
import org.activityinfo.legacy.shared.reports.model.layers.BubbleMapLayer;
import org.activityinfo.server.report.util.ColorUtil;

import java.text.DecimalFormat;

public class BubbleLegendRenderer {

    private static final int PADDING = 2;

    private static final int LABEL_HEIGHT = 12;

    private BubbleLayerLegend legend;
    private BubbleMapLayer layer;

    private DecimalFormat labelFormat;

    /**
     * True if we are drawing a labeld range of symbols (two) or just a simple
     * circle.
     */
    private boolean renderRange;

    private int width;
    private int height;

    private int bubbleCenterX;

    public BubbleLegendRenderer(BubbleLayerLegend legend) {
        this.legend = legend;
        this.layer = legend.getDefinition();

        this.renderRange = layer.getMinRadius() != layer.getMaxRadius() && legend.hasValues();

        calculateSize();

        labelFormat = new DecimalFormat();
        labelFormat.setMinimumFractionDigits(0);
        labelFormat.setMaximumFractionDigits(0);

    }

    private void calculateSize() {
        if (renderRange) {
            this.width = PADDING + (layer.getMaxRadius() * 2) + PADDING;
            this.height = PADDING +
                          (layer.getMinRadius() * 2) +
                          PADDING +
                          LABEL_HEIGHT +
                          PADDING +
                          (layer.getMaxRadius() * 2) +
                          PADDING +
                          LABEL_HEIGHT +
                          PADDING;

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

        this.bubbleCenterX = PADDING + layer.getMaxRadius();
    }

    public ItextGraphic createImage(ImageCreator creator) {

        ItextGraphic result = creator.create(width, height);
        Graphics2D g2d = result.getGraphics();

        if (renderRange) {
            drawSymbolRange(g2d);
        } else {
            ImageMapRenderer.drawBubble(g2d,
                    ColorUtil.colorFromString(layer.getBubbleColor()),
                    bubbleCenterX,
                    PADDING + layer.getMinRadius(),
                    layer.getMinRadius());
        }
        return result;
    }

    private void drawSymbolRange(Graphics2D g2d) {

        int y = 0;
        y += PADDING;
        y += layer.getMinRadius();

        ImageMapRenderer.drawBubble(g2d,
                ColorUtil.colorFromString(layer.getBubbleColor()),
                bubbleCenterX,
                y,
                layer.getMinRadius());

        y += layer.getMinRadius();
        y += PADDING;

        drawBubbleLegendLabel(g2d, bubbleCenterX, y, legend.getMinValue());

        y += PADDING;
        y += LABEL_HEIGHT;
        y += PADDING;
        y += layer.getMaxRadius();

        ImageMapRenderer.drawBubble(g2d,
                ColorUtil.colorFromString(layer.getBubbleColor()),
                bubbleCenterX,
                y,
                layer.getMaxRadius());

        y += layer.getMaxRadius();
        y += PADDING;

        drawBubbleLegendLabel(g2d, bubbleCenterX, y, legend.getMaxValue());

    }

    private void drawBubbleLegendLabel(Graphics2D g2d, int x, int y, double value) {
        Font font = new Font(Font.SANS_SERIF, Font.PLAIN, 10);
        String label = labelFormat.format(value);
        LineMetrics metrics = font.getLineMetrics(label, g2d.getFontRenderContext());
        Rectangle2D bounds = font.getStringBounds(label, g2d.getFontRenderContext());

        x -= bounds.getWidth() / 2d;
        y += metrics.getAscent();

        g2d.setColor(Color.BLACK);
        g2d.setFont(font);
        g2d.drawString(label, x, y);
    }

}