Source/platform/fonts/FontFaceCreationParams.h

/*
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#ifndef FontFaceCreationParams_h
#define FontFaceCreationParams_h

#include "wtf/Assertions.h"
#include "wtf/StringHasher.h"
#include "wtf/text/AtomicString.h"
#include "wtf/text/StringHash.h"

namespace blink {

enum FontFaceCreationType {
    CreateFontByFamily,
    CreateFontByFciIdAndTtcIndex
};

class FontFaceCreationParams {
    FontFaceCreationType m_creationType;
    AtomicString m_family;
    CString m_filename;
    int m_fontconfigInterfaceId;
    int m_ttcIndex;

public:
    FontFaceCreationParams()
        : m_creationType(CreateFontByFamily), m_family(AtomicString()), m_filename(CString()), m_fontconfigInterfaceId(0), m_ttcIndex(0)
    {
    }

    explicit FontFaceCreationParams(AtomicString family)
        : m_creationType(CreateFontByFamily), m_family(family), m_filename(CString()), m_fontconfigInterfaceId(0), m_ttcIndex(0)
    {
#if OS(WIN) && ENABLE(OPENTYPE_VERTICAL)
    // Leading "@" in the font name enables Windows vertical flow flag for the font.
    // Because we do vertical flow by ourselves, we don't want to use the Windows feature.
    // IE disregards "@" regardless of the orientation, so we follow the behavior and
    // normalize the family name.
    m_family = (m_family.isEmpty() || m_family[0] != '@') ? m_family : AtomicString(m_family.impl()->substring(1));
#endif
    }

    FontFaceCreationParams(CString filename, int fontconfigInterfaceId, int ttcIndex = 0)
        : m_creationType(CreateFontByFciIdAndTtcIndex), m_filename(filename), m_fontconfigInterfaceId(fontconfigInterfaceId), m_ttcIndex(ttcIndex)
    {
    }

    FontFaceCreationType creationType() const { return m_creationType; }
    AtomicString family() const
    {
        ASSERT(m_creationType == CreateFontByFamily);
        return m_family;
    }
    CString filename() const
    {
        ASSERT(m_creationType == CreateFontByFciIdAndTtcIndex);
        return m_filename;
    }
    int fontconfigInterfaceId() const
    {
        ASSERT(m_creationType == CreateFontByFciIdAndTtcIndex);
        return m_fontconfigInterfaceId;
    }
    int ttcIndex() const
    {
        ASSERT(m_creationType == CreateFontByFciIdAndTtcIndex);
        return m_ttcIndex;
    }

    unsigned hash() const
    {
        if (m_creationType == CreateFontByFciIdAndTtcIndex) {
            StringHasher hasher;
            // Hashing the filename and ints in this way is sensitive to character encoding
            // and endianness. However, since the hash is not transferred over a network
            // or permanently stored and only used for the runtime of Chromium,
            // this is not a concern.
            hasher.addCharacters(reinterpret_cast<const LChar*>(m_filename.data()), m_filename.length());
            hasher.addCharacters(reinterpret_cast<const LChar*>(&m_ttcIndex), sizeof(m_ttcIndex));
            hasher.addCharacters(reinterpret_cast<const LChar*>(&m_fontconfigInterfaceId), sizeof(m_fontconfigInterfaceId));
            return hasher.hash();
        }
        return CaseFoldingHash::hash(m_family.isEmpty() ? "" : m_family);
    }

    bool operator==(const FontFaceCreationParams& other) const
    {
        return m_creationType == other.m_creationType
            && equalIgnoringCase(m_family, other.m_family)
            && m_filename == other.m_filename
            && m_fontconfigInterfaceId == other.m_fontconfigInterfaceId
            && m_ttcIndex == other.m_ttcIndex;
    }

};

} // namespace blink

#endif // FontFaceCreationParams_h