/*

 * This file is part of the html renderer for KDE.

 *

 * Copyright (C) 2000 Lars Knoll (knoll@kde.org)

 *           (C) 2000 Antti Koivisto (koivisto@kde.org)

 *           (C) 2000 Dirk Mueller (mueller@kde.org)

 * Copyright (C) 2003, 2006 Apple Computer, Inc.

 *

 * 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; see the file COPYING.LIB.  If not, write to

 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,

 * Boston, MA 02110-1301, USA.

 *

 */

#ifndef Font_h

#define Font_h

#include "FontDescription.h"

#include <wtf/HashMap.h>

#if PLATFORM(QT)

#include <QtGui/qfont.h>

#include <QtGui/qfontmetrics.h>

#endif

namespace WebCore {

class FloatPoint;

class FloatRect;

class FontData;

class FontFallbackList;

class FontPlatformData;

class GlyphBuffer;

class GlyphPageTreeNode;

class GraphicsContext;

class IntPoint;

class TextStyle;

struct GlyphData;

class TextRun {

public:

    TextRun(const UChar* c, int len)

    :m_characters(c), m_len(len)

    {}

    TextRun(const String& s)

    :m_characters(s.characters()), m_len(s.length())

    {}

    const UChar operator[](int i) const { return m_characters[i]; }

    const UChar* data(int i) const { return &m_characters[i]; }

    const UChar* characters() const { return m_characters; }

    int length() const { return m_len; }

private:

    const UChar* m_characters;

    int m_len;

};

class Font {

public:

    Font();

    Font(const FontDescription&, short letterSpacing, short wordSpacing);

#if !PLATFORM(QT)

    Font(const FontPlatformData&, bool isPrinting); // This constructor is only used if the platform wants to start with a native font.

#endif

    ~Font();

    Font(const Font&);

    Font& operator=(const Font&);

    bool operator==(const Font& other) const

    {

        // Our FontData doesn't have to be checked, since checking the font description will be fine.

        // FIXME: This does not work if the font was made with the FontPlatformData constructor.

        return m_fontDescription == other.m_fontDescription

            && m_letterSpacing == other.m_letterSpacing

            && m_wordSpacing == other.m_wordSpacing;

    }

    bool operator!=(const Font& other) const {

        return !(*this == other);

    }

    const FontDescription& fontDescription() const { return m_fontDescription; }

    int pixelSize() const { return fontDescription().computedPixelSize(); }

    float size() const { return fontDescription().computedSize(); }

    void update() const;

    void drawText(GraphicsContext*, const TextRun&, const TextStyle&, const FloatPoint&, int from = 0, int to = -1) const;

    int width(const TextRun&, const TextStyle&) const;

    int width(const TextRun&) const;

    float floatWidth(const TextRun&, const TextStyle&) const;

    float floatWidth(const TextRun&) const;

    int offsetForPosition(const TextRun&, const TextStyle&, int position, bool includePartialGlyphs) const;

    FloatRect selectionRectForText(const TextRun&, const TextStyle&, const IntPoint&, int h, int from = 0, int to = -1) const;

    bool isSmallCaps() const { return m_fontDescription.smallCaps(); }

    short wordSpacing() const { return m_wordSpacing; }

    short letterSpacing() const { return m_letterSpacing; }

    void setWordSpacing(short s) { m_wordSpacing = s; }

    void setLetterSpacing(short s) { m_letterSpacing = s; }

    bool isFixedPitch() const;

    bool isPrinterFont() const { return m_fontDescription.usePrinterFont(); }

    FontFamily& firstFamily() { return m_fontDescription.firstFamily(); }

    const FontFamily& family() const { return m_fontDescription.family(); }

    bool italic() const { return m_fontDescription.italic(); }

    unsigned weight() const { return m_fontDescription.weight(); }

    bool bold() const { return m_fontDescription.bold(); }

#if !PLATFORM(QT)

    bool isPlatformFont() const { return m_isPlatformFont; }

#endif

#if PLATFORM(QT)

    inline const QFont &font() const { return m_font; }

    inline const QFont &scFont() const { return m_scFont; }

#endif

    // Metrics that we query the FontFallbackList for.

    int ascent() const;

    int descent() const;

    int height() const { return ascent() + descent(); }

    int lineSpacing() const;

    float xHeight() const;

    int spaceWidth() const;

    int tabWidth() const { return 8 * spaceWidth(); }

#if !PLATFORM(QT)

    const FontData* primaryFont() const;

    const FontData* fontDataAt(unsigned) const;

    const GlyphData& glyphDataForCharacter(UChar32, const UChar* cluster, unsigned clusterLength, bool mirror, bool attemptFontSubstitution) const;

    // Used for complex text, and does not utilize the glyph map cache.

    const FontData* fontDataForCharacters(const UChar*, int length) const;

private:

    bool canUseGlyphCache(const TextRun&) const;

    void drawSimpleText(GraphicsContext*, const TextRun&, const TextStyle&, const FloatPoint&, int from, int to) const;

    void drawGlyphs(GraphicsContext*, const FontData*, const GlyphBuffer&, int from, int to, const FloatPoint&) const;

    void drawGlyphBuffer(GraphicsContext*, const GlyphBuffer&, const TextRun&, const TextStyle&, const FloatPoint&) const;

    void drawComplexText(GraphicsContext*, const TextRun&, const TextStyle&, const FloatPoint&, int from, int to) const;

    float floatWidthForSimpleText(const TextRun&, const TextStyle&, GlyphBuffer*) const;

    float floatWidthForComplexText(const TextRun&, const TextStyle&) const;

    int offsetForPositionForSimpleText(const TextRun&, const TextStyle&, int position, bool includePartialGlyphs) const;

    int offsetForPositionForComplexText(const TextRun&, const TextStyle&, int position, bool includePartialGlyphs) const;

    FloatRect selectionRectForSimpleText(const TextRun&, const TextStyle&, const IntPoint&, int h, int from, int to) const;

    FloatRect selectionRectForComplexText(const TextRun&, const TextStyle&, const IntPoint&, int h, int from, int to) const;

#endif

    friend struct WidthIterator;

    // Useful for debugging the different font rendering code paths.

public:

#if !PLATFORM(QT)

    enum CodePath { Auto, Simple, Complex };

    static void setCodePath(CodePath);

    static CodePath codePath;

    static const uint8_t gRoundingHackCharacterTable[256];

    static bool isRoundingHackCharacter(UChar32 c)

    {

        return (((c & ~0xFF) == 0 && gRoundingHackCharacterTable[c])); 

    }

#endif

    static bool treatAsSpace(UChar c) { return c == ' ' || c == '\t' || c == '\n' || c == 0x00A0; }

    static bool treatAsZeroWidthSpace(UChar c) { return c < 0x20 || (c >= 0x7F && c < 0xA0) || c == 0x200e || c == 0x200f || c == 0x200b; }

private:

    FontDescription m_fontDescription;

#if !PLATFORM(QT)

    mutable RefPtr<FontFallbackList> m_fontList;

    mutable HashMap<int, GlyphPageTreeNode*> m_pages;

    mutable GlyphPageTreeNode* m_pageZero;

#endif

    short m_letterSpacing;

    short m_wordSpacing;

#if !PLATFORM(QT)

    bool m_isPlatformFont;

#else

    QFont m_font;

    QFont m_scFont;

    int m_spaceWidth;

#endif

};

}

#endif