/*
 *    Geotoolkit - An Open Source Java GIS Toolkit
 *    http://www.geotoolkit.org
 *
 *    (C) 2008 - 2010, Geomatys
 *
 *    This library 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;
 *    version 2.1 of the License.
 *
 *    This library 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.
 */
package org.geotoolkit.display2d.style.renderer;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.Paint;
import java.awt.Shape;
import java.awt.font.FontRenderContext;
import java.awt.font.GlyphVector;
import java.awt.geom.Rectangle2D;
import org.geotoolkit.display2d.GO2Utilities;
import org.geotoolkit.display2d.canvas.RenderingContext2D;
import org.geotoolkit.display2d.style.CachedTextSymbolizer;
import org.geotoolkit.map.MapLayer;
import org.opengis.filter.expression.Expression;
import org.opengis.style.TextSymbolizer;

/**
 * @author Johann Sorel (Geomatys)
 * @module
 */
public class DefaultTextSymbolizerRendererService extends AbstractSymbolizerRendererService<TextSymbolizer, CachedTextSymbolizer>{

    private static final String GLYPH_CANDIDATE = "T";
    
    @Override
    public boolean isGroupSymbolizer() {
        return false;
    }
    
    /**
     * {@inheritDoc }
     */
    @Override
    public Class<TextSymbolizer> getSymbolizerClass() {
        return TextSymbolizer.class;
    }

    /**
     * {@inheritDoc }
     */
    @Override
    public Class<CachedTextSymbolizer> getCachedSymbolizerClass() {
        return CachedTextSymbolizer.class;
    }

    /**
     * {@inheritDoc }
     */
    @Override
    public CachedTextSymbolizer createCachedSymbolizer(final TextSymbolizer symbol) {
        return new CachedTextSymbolizer(symbol,this);
    }

    /**
     * {@inheritDoc }
     */
    @Override
    public SymbolizerRenderer createRenderer(final CachedTextSymbolizer symbol, final RenderingContext2D context) {
        return new DefaultTextSymbolizerRenderer(this, symbol, context);
    }

    /**
     * {@inheritDoc }
     */
    @Override
    public void glyph(final Graphics2D g, final Rectangle2D rectangle, final CachedTextSymbolizer symbol, final MapLayer layer) {
        g.setClip(rectangle);

        final String family;
        if(!symbol.getSource().getFont().getFamily().isEmpty() && 
            symbol.getSource().getFont().getFamily().get(0)!=null){
            family = symbol.getSource().getFont().getFamily().get(0).toString();
        }else{
            family = "Dialog";
        }

        /*
         * Build the glyph font. We get the font of input symbolizer and apply a filter to ensure
         * font size will not overlap more than a quarter of the asked rectangle.
         */
        final Font font;
        final int defaultSize = (int) (rectangle.getHeight()/2);
        final Font cachedFont = symbol.getJ2dFont(GLYPH_CANDIDATE, 1);
        if (cachedFont != null) {
            if (cachedFont.getSize() > defaultSize) {
                font = cachedFont.deriveFont((float)defaultSize);
            } else {
                font = cachedFont;
            }
        } else {
            font = new Font(family, Font.PLAIN, defaultSize);
        }
        
        final FontRenderContext frc = g.getFontRenderContext();
        final GlyphVector glyphVector = font.createGlyphVector(frc, GLYPH_CANDIDATE);
        final Shape shape = glyphVector.getOutline();

        g.translate(rectangle.getMinX()+3, rectangle.getMaxY()-3);

        if(symbol.getHalo() != null){

            Paint paint = null;
            float width = 1;

            if(GO2Utilities.isStatic(symbol.getSource().getHalo().getFill().getColor())){
                paint = symbol.getSource().getHalo().getFill().getColor().evaluate(null, Color.class);
            }

            if(paint == null){
                paint = Color.WHITE;
            }

            final Expression expWidth = symbol.getSource().getHalo().getRadius();
            if(GO2Utilities.isStatic(expWidth)){
                width = expWidth.evaluate(null, Number.class).floatValue();
            }else{
                width = 1;
            }

            if(width > 0){
                g.setStroke(new BasicStroke(width*2+1, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND));
                g.setPaint(paint);
                g.draw(shape);
            }
        }


        Paint paint = null;
        if(GO2Utilities.isStatic(symbol.getSource().getFill().getColor())){
            paint = symbol.getSource().getFill().getColor().evaluate(null, Color.class);
        }

        if(paint == null){
            paint = Color.BLACK;
        }

        g.setPaint(paint);
        g.setFont(font);
        g.drawString(GLYPH_CANDIDATE, 0, 0);
    }

}