/* -*- Mode: Java; tab-width: 4; c-basic-offset: 4 -*- */
/*
 * Copyright 2002 Paulo Soares
 *
 *
 * The Original Code is 'iText, a free JAVA-PDF library'.
 *
 * The Initial Developer of the Original Code is Bruno Lowagie. Portions created by
 * the Initial Developer are Copyright (C) 1999, 2000, 2001, 2002 by Bruno Lowagie.
 * All Rights Reserved.
 * Co-Developer of the code is Paulo Soares. Portions created by the Co-Developer
 * are Copyright (C) 2000, 2001, 2002 by Paulo Soares. All Rights Reserved.
 *
 * Contributor(s): all the names of the contributors are added in the source code
 * where applicable.
 *
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 * 
 * 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
 * Library General Public License for more details.
 * 
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
 * Boston, MA  02110-1301, USA.
 *
 *
 * If you didn't download this code from the following link, you should check if
 * you aren't using an obsolete version:
 * http://www.lowagie.com/iText/
 */
package com.lowagie.text.pdf;

import java.awt.Color;
import java.io.IOException;
/** Implements the shading dictionary (or stream).
 *
 * @author Paulo Soares (psoares@consiste.pt)
 */
public class PdfShading {

    protected PdfDictionary shading;
    
    protected PdfWriter writer;
    
    protected int shadingType;
    
    protected ColorDetails colorDetails;
    
    protected PdfName shadingName;
    
    protected PdfIndirectReference shadingReference;
    
    private Color cspace;
    
    /** Holds value of property bBox. */
    protected float[] bBox;
    
    /** Holds value of property antiAlias. */
    protected boolean antiAlias = false;
    
    /** Creates new PdfShading */
    protected PdfShading(PdfWriter writer) {
        this.writer = writer;
    }
    
    protected void setColorSpace(Color color) {
        cspace = color;
        int type = ExtendedColor.getType(color);
        PdfObject colorSpace = null;
        switch (type) {
            case ExtendedColor.TYPE_GRAY: {
                colorSpace = PdfName.DEVICEGRAY;
                break;
            }
            case ExtendedColor.TYPE_CMYK: {
                colorSpace = PdfName.DEVICECMYK;
                break;
            }
            case ExtendedColor.TYPE_SEPARATION: {
                SpotColor spot = (SpotColor)color;
                colorDetails = writer.addSimple(spot.getPdfSpotColor());
                colorSpace = colorDetails.getIndirectReference();
                break;
            }
            case ExtendedColor.TYPE_PATTERN:
            case ExtendedColor.TYPE_SHADING: {
                throwColorSpaceError();
            }
            default:
                colorSpace = PdfName.DEVICERGB;
                break;
        }
        shading.put(PdfName.COLORSPACE, colorSpace);
    }
    
    Color getColorSpace() {
        return cspace;
    }
    
    public static void throwColorSpaceError() {
        throw new IllegalArgumentException("A tiling or shading pattern cannot be used as a color space in a shading pattern");
    }
    
    public static void checkCompatibleColors(Color c1, Color c2) {
        int type1 = ExtendedColor.getType(c1);
        int type2 = ExtendedColor.getType(c2);
        if (type1 != type2)
            throw new IllegalArgumentException("Both colors must be of the same type.");
        if (type1 == ExtendedColor.TYPE_SEPARATION && ((SpotColor)c1).getPdfSpotColor() != ((SpotColor)c2).getPdfSpotColor())
            throw new IllegalArgumentException("The spot color must be the same, only the tint can vary.");
        if (type1 == ExtendedColor.TYPE_PATTERN || type1 == ExtendedColor.TYPE_SHADING)
            throwColorSpaceError();
    }
    
    public static float[] getColorArray(Color color) {
        int type = ExtendedColor.getType(color);
        switch (type) {
            case ExtendedColor.TYPE_GRAY: {
                return new float[]{((GrayColor)color).getGray()};
            }
            case ExtendedColor.TYPE_CMYK: {
                CMYKColor cmyk = (CMYKColor)color;
                return new float[]{cmyk.getCyan(), cmyk.getMagenta(), cmyk.getYellow(), cmyk.getBlack()};
            }
            case ExtendedColor.TYPE_SEPARATION: {
                return new float[]{((SpotColor)color).getTint()};
            }
            case ExtendedColor.TYPE_RGB: {
                return new float[]{color.getRed() / 255f, color.getGreen() / 255f, color.getBlue() / 255f};
            }
        }
        throwColorSpaceError();
        return null;
    }

    public static PdfShading type1(PdfWriter writer, Color colorSpace, float domain[], float tMatrix[], PdfFunction function) {
        PdfShading sp = new PdfShading(writer);
        sp.shading = new PdfDictionary();
        sp.shadingType = 1;
        sp.shading.put(PdfName.SHADINGTYPE, new PdfNumber(sp.shadingType));
        sp.setColorSpace(colorSpace);
        if (domain != null)
            sp.shading.put(PdfName.m_DOMAIN, new PdfArray(domain)); // ssteward
        if (tMatrix != null)
            sp.shading.put(PdfName.MATRIX, new PdfArray(tMatrix));
        sp.shading.put(PdfName.FUNCTION, function.getReference());
        return sp;
    }
    
    public static PdfShading type2(PdfWriter writer, Color colorSpace, float coords[], float domain[], PdfFunction function, boolean extend[]) {
        PdfShading sp = new PdfShading(writer);
        sp.shading = new PdfDictionary();
        sp.shadingType = 2;
        sp.shading.put(PdfName.SHADINGTYPE, new PdfNumber(sp.shadingType));
        sp.setColorSpace(colorSpace);
        sp.shading.put(PdfName.COORDS, new PdfArray(coords));
        if (domain != null)
            sp.shading.put(PdfName.m_DOMAIN, new PdfArray(domain)); // ssteward
        sp.shading.put(PdfName.FUNCTION, function.getReference());
        if (extend != null && (extend[0] || extend[1])) {
            PdfArray array = new PdfArray(extend[0] ? PdfBoolean.PDFTRUE : PdfBoolean.PDFFALSE);
            array.add(extend[1] ? PdfBoolean.PDFTRUE : PdfBoolean.PDFFALSE);
            sp.shading.put(PdfName.EXTEND, array);
        }
        return sp;
    }

    public static PdfShading type3(PdfWriter writer, Color colorSpace, float coords[], float domain[], PdfFunction function, boolean extend[]) {
        PdfShading sp = type2(writer, colorSpace, coords, domain, function, extend);
        sp.shadingType = 3;
        sp.shading.put(PdfName.SHADINGTYPE, new PdfNumber(sp.shadingType));
        return sp;
    }
    
    public static PdfShading simpleAxial(PdfWriter writer, float x0, float y0, float x1, float y1, Color startColor, Color endColor, boolean extendStart, boolean extendEnd) {
        checkCompatibleColors(startColor, endColor);
        PdfFunction function = PdfFunction.type2(writer, new float[]{0, 1}, null, getColorArray(startColor),
            getColorArray(endColor), 1);
        return type2(writer, startColor, new float[]{x0, y0, x1, y1}, null, function, new boolean[]{extendStart, extendEnd});
    }
    
    public static PdfShading simpleAxial(PdfWriter writer, float x0, float y0, float x1, float y1, Color startColor, Color endColor) {
        return simpleAxial(writer, x0, y0, x1, y1, startColor, endColor, true, true);
    }
    
    public static PdfShading simpleRadial(PdfWriter writer, float x0, float y0, float r0, float x1, float y1, float r1, Color startColor, Color endColor, boolean extendStart, boolean extendEnd) {
        checkCompatibleColors(startColor, endColor);
        PdfFunction function = PdfFunction.type2(writer, new float[]{0, 1}, null, getColorArray(startColor),
            getColorArray(endColor), 1);
        return type3(writer, startColor, new float[]{x0, y0, r0, x1, y1, r1}, null, function, new boolean[]{extendStart, extendEnd});
    }

    public static PdfShading simpleRadial(PdfWriter writer, float x0, float y0, float r0, float x1, float y1, float r1, Color startColor, Color endColor) {
        return simpleRadial(writer, x0, y0, r0, x1, y1, r1, startColor, endColor, true, true);
    }

    PdfName getShadingName() {
        return shadingName;
    }
    
    PdfIndirectReference getShadingReference() {
        if (shadingReference == null)
            shadingReference = writer.getPdfIndirectReference();
        return shadingReference;
    }
    
    void setName(int number) {
        shadingName = new PdfName("Sh" + number);
    }
    
    void addToBody() throws IOException {
        if (bBox != null)
            shading.put(PdfName.BBOX, new PdfArray(bBox));
        if (antiAlias)
            shading.put(PdfName.ANTIALIAS, PdfBoolean.PDFTRUE);
        writer.addToBody(shading, getShadingReference());
    }
    
    PdfWriter getWriter() {
        return writer;
    }
    
    ColorDetails getColorDetails() {
        return colorDetails;
    }
    
    public float[] getBBox() {
        return bBox;
    }
    
    public void setBBox(float[] bBox) {
        if (bBox.length != 4)
            throw new IllegalArgumentException("BBox must be a 4 element array.");
        this.bBox = bBox;
    }
    
    public boolean isAntiAlias() {
        return antiAlias;
    }
    
    public void setAntiAlias(boolean antiAlias) {
        this.antiAlias = antiAlias;
    }
    
}
