/*

 * Copyright (c) 2003, 2005, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package sun.font;

import java.awt.Font;

import java.awt.font.FontRenderContext;

import java.awt.geom.AffineTransform;

import static sun.awt.SunHints.*;

/*

 * This class encapsulates every thing needed that distinguishes a strike.

 * It can be used as a key to locate a FontStrike in a Hashmap/cache.

 * It is not mutatable, but contains mutatable AffineTransform objects,

 * which for performance reasons it does not keep private copies of.

 * Therefore code constructing these must pass in transforms it guarantees

 * not to mutate.

 */

public class FontStrikeDesc {

    /* Values to use as a mask that is used for faster comparison of

     * two strikes using just an int equality test.

     * The ones we don't use are listed here but commented out.

     * ie style is already built and hint "OFF" values are zero.

     * Note that this is used as a strike key and the same strike is used

     * for HRGB and HBGR, so only the orientation needed (H or V) is needed

     * to construct and distinguish a FontStrikeDesc. The rgb ordering

     * needed for rendering is stored in the graphics state.

     */

//     static final int STYLE_PLAIN       = Font.PLAIN;            // 0x0000

//     static final int STYLE_BOLD        = Font.BOLD;             // 0x0001

//     static final int STYLE_ITALIC      = Font.ITALIC;           // 0x0002

//     static final int STYLE_BOLDITALIC  = Font.BOLD|Font.ITALIC; // 0x0003

//     static final int AA_OFF            = 0x0000;

    static final int AA_ON             = 0x0010;

    static final int AA_LCD_H          = 0x0020;

    static final int AA_LCD_V          = 0x0040;

//     static final int FRAC_METRICS_OFF  = 0x0000;

    static final int FRAC_METRICS_ON   = 0x0100;

    static final int FRAC_METRICS_SP   = 0x0200;

    /* devTx is to get an inverse transform to get user space values

     * for metrics. Its not used otherwise, as the glyphTx is the important

     * one. But it does mean that a strike representing a 6pt font and identity

     * graphics transform is not equal to one for a 12 pt font and 2x scaled

     * graphics transform. Its likely to be very rare that this causes

     * duplication.

     */

    AffineTransform devTx;

    AffineTransform glyphTx; // all of ptSize, Font tx and Graphics tx.

    int style;

    int aaHint;

    int fmHint;

    private int hashCode;

    private int valuemask;

    public int hashCode() {

        /* Can cache hashcode since a strike(desc) is immutable.*/

        if (hashCode == 0) {

            hashCode = glyphTx.hashCode() + devTx.hashCode() + valuemask;

        }

        return hashCode;

    }

    public boolean equals(Object obj) {

        try {

            FontStrikeDesc desc = (FontStrikeDesc)obj;

            return (desc.valuemask == this.valuemask &&

                    desc.glyphTx.equals(this.glyphTx) &&

                    desc.devTx.equals(this.devTx));

        } catch (Exception e) {

            /* class cast or NP exceptions should not happen often, if ever,

             * and I am hoping that this is faster than an instanceof check.

             */

            return false;

        }

    }

    FontStrikeDesc() {

        // used with init

    }

    /* This maps a public text AA hint value into one of the subset of values

     * used to index strikes. For the purpose of the strike cache there are

     * only 4 values : OFF, ON, LCD_HRGB, LCD_VRGB.

     * Font and ptSize are needed to resolve the 'gasp' table. The ptSize

     * must therefore include device and font transforms.

     */

    public static int getAAHintIntVal(Object aa, Font2D font2D, int ptSize) {

        if (aa == VALUE_TEXT_ANTIALIAS_OFF ||

            aa == VALUE_TEXT_ANTIALIAS_DEFAULT) {

            return INTVAL_TEXT_ANTIALIAS_OFF;

        } else if (aa == VALUE_TEXT_ANTIALIAS_ON) {

            return INTVAL_TEXT_ANTIALIAS_ON;

        } else if (aa == VALUE_TEXT_ANTIALIAS_GASP) {

            if (font2D.useAAForPtSize(ptSize)) {

                return INTVAL_TEXT_ANTIALIAS_ON;

            } else {

                return INTVAL_TEXT_ANTIALIAS_OFF;

            }

        } else if (aa == VALUE_TEXT_ANTIALIAS_LCD_HRGB ||

                   aa == VALUE_TEXT_ANTIALIAS_LCD_HBGR) {

            return INTVAL_TEXT_ANTIALIAS_LCD_HRGB;

        } else if (aa == VALUE_TEXT_ANTIALIAS_LCD_VRGB ||

                   aa == VALUE_TEXT_ANTIALIAS_LCD_VBGR) {

            return INTVAL_TEXT_ANTIALIAS_LCD_VRGB;

        } else {

            return INTVAL_TEXT_ANTIALIAS_OFF;

        }

    }

    /* This maps a public text AA hint value into one of the subset of values

     * used to index strikes. For the purpose of the strike cache there are

     * only 4 values : OFF, ON, LCD_HRGB, LCD_VRGB.

     * Font and FontRenderContext are needed to resolve the 'gasp' table.

     * This is similar to the method above, but used by callers which have not

     * already calculated the glyph device point size.

     */

    public static int getAAHintIntVal(Font2D font2D, Font font,

                                      FontRenderContext frc) {

        Object aa = frc.getAntiAliasingHint();

        if (aa == VALUE_TEXT_ANTIALIAS_OFF ||

            aa == VALUE_TEXT_ANTIALIAS_DEFAULT) {

            return INTVAL_TEXT_ANTIALIAS_OFF;

        } else if (aa == VALUE_TEXT_ANTIALIAS_ON) {

            return INTVAL_TEXT_ANTIALIAS_ON;

        } else if (aa == VALUE_TEXT_ANTIALIAS_GASP) {

            /* FRC.isIdentity() would have been useful */

            int ptSize;

            AffineTransform tx = frc.getTransform();

            if (tx.isIdentity() && !font.isTransformed()) {

                ptSize = font.getSize();

            } else {

                /* one or both transforms is not identity */

                float size = font.getSize2D();

                if (tx.isIdentity()) {

                    tx = font.getTransform();

                    tx.scale(size, size);

                } else {

                    tx.scale(size, size);

                    if (font.isTransformed()) {

                        tx.concatenate(font.getTransform());

                    }

                }

                double shearx = tx.getShearX();

                double scaley = tx.getScaleY();

                if (shearx != 0) {

                    scaley = Math.sqrt(shearx * shearx + scaley * scaley);

                }

                ptSize = (int)(Math.abs(scaley)+0.5);

            }

            if (font2D.useAAForPtSize(ptSize)) {

                return INTVAL_TEXT_ANTIALIAS_ON;

            } else {

                return INTVAL_TEXT_ANTIALIAS_OFF;

            }

        } else if (aa == VALUE_TEXT_ANTIALIAS_LCD_HRGB ||

                   aa == VALUE_TEXT_ANTIALIAS_LCD_HBGR) {

            return INTVAL_TEXT_ANTIALIAS_LCD_HRGB;

        } else if (aa == VALUE_TEXT_ANTIALIAS_LCD_VRGB ||

                   aa == VALUE_TEXT_ANTIALIAS_LCD_VBGR) {

            return INTVAL_TEXT_ANTIALIAS_LCD_VRGB;

        } else {

            return INTVAL_TEXT_ANTIALIAS_OFF;

        }

    }

    public static int getFMHintIntVal(Object fm) {

        if (fm == VALUE_FRACTIONALMETRICS_OFF ||

            fm == VALUE_FRACTIONALMETRICS_DEFAULT) {

            return INTVAL_FRACTIONALMETRICS_OFF;

        } else {

            return INTVAL_FRACTIONALMETRICS_ON;

        }

    }

    public FontStrikeDesc(AffineTransform devAt, AffineTransform at,

                          int fStyle, int aa, int fm) {

        devTx = devAt;

        glyphTx = at; // not cloning glyphTx. Callers trusted to not mutate it.

        style = fStyle;

        aaHint = aa;

        fmHint = fm;

        valuemask = fStyle;

        switch (aa) {

           case INTVAL_TEXT_ANTIALIAS_OFF :

                break;

           case INTVAL_TEXT_ANTIALIAS_ON  :

                valuemask |= AA_ON;

                break;

           case INTVAL_TEXT_ANTIALIAS_LCD_HRGB :

           case INTVAL_TEXT_ANTIALIAS_LCD_HBGR :

                valuemask |= AA_LCD_H;

                break;

           case INTVAL_TEXT_ANTIALIAS_LCD_VRGB :

           case INTVAL_TEXT_ANTIALIAS_LCD_VBGR :

                valuemask |= AA_LCD_V;

                break;

           default: break;

        }

        if (fm == INTVAL_FRACTIONALMETRICS_ON) {

           valuemask |= FRAC_METRICS_ON;

        }

    }

    FontStrikeDesc(FontStrikeDesc desc) {

        devTx = desc.devTx;

        // Clone the TX in this case as this is called when its known

        // that "desc" is being re-used by its creator.

        glyphTx = (AffineTransform)desc.glyphTx.clone();

        style = desc.style;

        aaHint = desc.aaHint;

        fmHint = desc.fmHint;

        hashCode = desc.hashCode;

        valuemask = desc.valuemask;

    }

    public String toString() {

        return "FontStrikeDesc: Style="+style+ " AA="+aaHint+ " FM="+fmHint+

            " devTx="+devTx+ " devTx.FontTx.ptSize="+glyphTx;

    }

}