/*

 * Copyright (C) 2009 Google Inc. All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions are

 * met:

 *

 *     * Redistributions of source code must retain the above copyright

 * notice, this list of conditions and the following disclaimer.

 *     * Redistributions in binary form must reproduce the above

 * copyright notice, this list of conditions and the following disclaimer

 * in the documentation and/or other materials provided with the

 * distribution.

 *     * Neither the name of Google Inc. nor the names of its

 * contributors may be used to endorse or promote products derived from

 * this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

#include "config.h"

#include "WebFontInfo.h"

#include "WebFontRenderStyle.h"

#include <fontconfig/fontconfig.h>

#include <string.h>

#include <unicode/utf16.h>

namespace WebKit {

WebCString WebFontInfo::familyForChars(const WebUChar* characters, size_t numCharacters)

{

    FcCharSet* cset = FcCharSetCreate();

    for (size_t i = 0; i < numCharacters; ++i) {

        if (U16_IS_SURROGATE(characters[i])

         && U16_IS_SURROGATE_LEAD(characters[i])

         && i != numCharacters - 1

         && U16_IS_TRAIL(characters[i + 1])) {

              FcCharSetAddChar(cset, U16_GET_SUPPLEMENTARY(characters[i], characters[i+1]));

          i++;

        } else

              FcCharSetAddChar(cset, characters[i]);

    }

    FcPattern* pattern = FcPatternCreate();

    FcValue fcvalue;

    fcvalue.type = FcTypeCharSet;

    fcvalue.u.c = cset;

    FcPatternAdd(pattern, FC_CHARSET, fcvalue, FcFalse);

    fcvalue.type = FcTypeBool;

    fcvalue.u.b = FcTrue;

    FcPatternAdd(pattern, FC_SCALABLE, fcvalue, FcFalse);

    FcConfigSubstitute(0, pattern, FcMatchPattern);

    FcDefaultSubstitute(pattern);

    FcResult result;

    FcFontSet* fontSet = FcFontSort(0, pattern, 0, 0, &result);

    FcPatternDestroy(pattern);

    FcCharSetDestroy(cset);

    if (!fontSet)

        return WebCString();

    // Older versions of fontconfig have a bug where they cannot select

    // only scalable fonts so we have to manually filter the results.

    for (int i = 0; i < fontSet->nfont; ++i) {

        FcPattern* current = fontSet->fonts[i];

        FcBool isScalable;

        if (FcPatternGetBool(current, FC_SCALABLE, 0, &isScalable) != FcResultMatch

            || !isScalable)

            continue;

        // fontconfig can also return fonts which are unreadable

        FcChar8* cFilename;

        if (FcPatternGetString(current, FC_FILE, 0, &cFilename) != FcResultMatch)

            continue;

        if (access(reinterpret_cast<char*>(cFilename), R_OK))

            continue;

        FcChar8* family;

        WebCString result;

        if (FcPatternGetString(current, FC_FAMILY, 0, &family) == FcResultMatch) {

            const char* charFamily = reinterpret_cast<char*>(family);

            result = WebCString(charFamily, strlen(charFamily));

        }

        FcFontSetDestroy(fontSet);

        return result;

    }

    FcFontSetDestroy(fontSet);

    return WebCString();

}

void WebFontInfo::renderStyleForStrike(const char* family, int sizeAndStyle, WebFontRenderStyle* out)

{

    bool isBold = sizeAndStyle & 1;

    bool isItalic = sizeAndStyle & 2;

    int pixelSize = sizeAndStyle >> 2;

    FcPattern* pattern = FcPatternCreate();

    FcValue fcvalue;

    fcvalue.type = FcTypeString;

    fcvalue.u.s = reinterpret_cast<const FcChar8 *>(family);

    FcPatternAdd(pattern, FC_FAMILY, fcvalue, FcFalse);

    fcvalue.type = FcTypeInteger;

    fcvalue.u.i = isBold ? FC_WEIGHT_BOLD : FC_WEIGHT_NORMAL;

    FcPatternAdd(pattern, FC_WEIGHT, fcvalue, FcFalse);

    fcvalue.type = FcTypeInteger;

    fcvalue.u.i = isItalic ? FC_SLANT_ITALIC : FC_SLANT_ROMAN;

    FcPatternAdd(pattern, FC_SLANT, fcvalue, FcFalse);

    fcvalue.type = FcTypeBool;

    fcvalue.u.b = FcTrue;

    FcPatternAdd(pattern, FC_SCALABLE, fcvalue, FcFalse);

    fcvalue.type = FcTypeDouble;

    fcvalue.u.d = pixelSize;

    FcPatternAdd(pattern, FC_SIZE, fcvalue, FcFalse);

    FcConfigSubstitute(0, pattern, FcMatchPattern);

    FcDefaultSubstitute(pattern);

    FcResult result;

    // Some versions of fontconfig don't actually write a value into result.

    // However, it's not clear from the documentation if result should be a

    // non-0 pointer: future versions might expect to be able to write to

    // it. So we pass in a valid pointer and ignore it.

    FcPattern* match = FcFontMatch(0, pattern, &result);

    FcPatternDestroy(pattern);

    out->setDefaults();

    if (!match) {

        FcPatternDestroy(match);

        return;

    }

    FcBool b;

    int i;

    if (FcPatternGetBool(match, FC_ANTIALIAS, 0, &b) == FcResultMatch)

        out->useAntiAlias = b;

    if (FcPatternGetBool(match, FC_EMBEDDED_BITMAP, 0, &b) == FcResultMatch)

        out->useBitmaps = b;

    if (FcPatternGetBool(match, FC_AUTOHINT, 0, &b) == FcResultMatch)

        out->useAutoHint = b;

    if (FcPatternGetBool(match, FC_HINTING, 0, &b) == FcResultMatch)

        out->useHinting = b;

    if (FcPatternGetInteger(match, FC_HINT_STYLE, 0, &i) == FcResultMatch)

        out->hintStyle = i;

    if (FcPatternGetInteger(match, FC_RGBA, 0, &i) == FcResultMatch) {

        switch (i) {

        case FC_RGBA_NONE:

            out->useSubpixel = 0;

            break;

        case FC_RGBA_RGB:

        case FC_RGBA_BGR:

        case FC_RGBA_VRGB:

        case FC_RGBA_VBGR:

            out->useSubpixel = 1;

            break;

        default:

            // This includes FC_RGBA_UNKNOWN.

            out->useSubpixel = 2;

            break;

        }

    }

    FcPatternDestroy(match);

}

} // namespace WebKit