FontTranscoder.cpp   [plain text]

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#include "config.h"
#include "FontTranscoder.h"

#include "FontDescription.h"
#include "TextEncoding.h"
#include <wtf/unicode/CharacterNames.h>

namespace WebCore {

FontTranscoder::FontTranscoder()
{
    m_converterTypes.add("MS PGothic", BackslashToYenSign);
    UChar unicodeNameMSPGothic[] = {0xFF2D, 0xFF33, 0x0020, 0xFF30, 0x30B4, 0x30B7, 0x30C3, 0x30AF};
    m_converterTypes.add(AtomicString(unicodeNameMSPGothic, WTF_ARRAY_LENGTH(unicodeNameMSPGothic)), BackslashToYenSign);

    m_converterTypes.add("MS PMincho", BackslashToYenSign);
    UChar unicodeNameMSPMincho[] = {0xFF2D, 0xFF33, 0x0020, 0xFF30, 0x660E, 0x671D};
    m_converterTypes.add(AtomicString(unicodeNameMSPMincho, WTF_ARRAY_LENGTH(unicodeNameMSPMincho)), BackslashToYenSign);

    m_converterTypes.add("MS Gothic", BackslashToYenSign);
    UChar unicodeNameMSGothic[] = {0xFF2D, 0xFF33, 0x0020, 0x30B4, 0x30B7, 0x30C3, 0x30AF};
    m_converterTypes.add(AtomicString(unicodeNameMSGothic, WTF_ARRAY_LENGTH(unicodeNameMSGothic)), BackslashToYenSign);

    m_converterTypes.add("MS Mincho", BackslashToYenSign);
    UChar unicodeNameMSMincho[] = {0xFF2D, 0xFF33, 0x0020, 0x660E, 0x671D};
    m_converterTypes.add(AtomicString(unicodeNameMSMincho, WTF_ARRAY_LENGTH(unicodeNameMSMincho)), BackslashToYenSign);

    m_converterTypes.add("Meiryo", BackslashToYenSign);
    UChar unicodeNameMeiryo[] = {0x30E1, 0x30A4, 0x30EA, 0x30AA};
    m_converterTypes.add(AtomicString(unicodeNameMeiryo, WTF_ARRAY_LENGTH(unicodeNameMeiryo)), BackslashToYenSign);
}

FontTranscoder::ConverterType FontTranscoder::converterType(const FontDescription& fontDescription, const TextEncoding* encoding) const
{
    const AtomicString& fontFamily = fontDescription.firstFamily();
    if (!fontFamily.isNull()) {
        HashMap<AtomicString, ConverterType>::const_iterator found = m_converterTypes.find(fontFamily);
        if (found != m_converterTypes.end())
            return found->value;
    }

    // IE's default fonts for Japanese encodings change backslashes into yen signs.
    // We emulate this behavior only when no font is explicitly specified.
    if (encoding && encoding->backslashAsCurrencySymbol() != '\\' && !fontDescription.isSpecifiedFont())
        return BackslashToYenSign;

    return NoConversion;
}

void FontTranscoder::convert(String& text, const FontDescription& fontDescription, const TextEncoding* encoding) const
{
    switch (converterType(fontDescription, encoding)) {
    case BackslashToYenSign: {
        // FIXME: TextEncoding.h has similar code. We need to factor them out.
        text.replace('\\', yenSign);
        break;
    }
    case NoConversion:
    default:
        ASSERT_NOT_REACHED();
    }
}

bool FontTranscoder::needsTranscoding(const FontDescription& fontDescription, const TextEncoding* encoding) const
{
    ConverterType type = converterType(fontDescription, encoding);
    return type != NoConversion;
}

FontTranscoder& fontTranscoder()
{
    static FontTranscoder* transcoder = new FontTranscoder;
    return *transcoder;
}

} // namespace WebCore