PdfDifferenceEncoding.h

 
#ifndef PDF_DIFFERENCE_ENCODING_H
#define PDF_DIFFERENCE_ENCODING_H
 
#include "PdfEncodingMap.h"
#include "PdfArray.h"
 
namespace PoDoFo {
 
class PdfFontMetrics;
 
class PODOFO_API PdfDifferenceList final
{
    struct Difference
    {
        unsigned char Code = 0;
        PdfName Name;
        char32_t MappedCodePoint = U'\0';
    };
 
    using List = std::vector<Difference>;
    using iterator = std::vector<Difference>::iterator;
    using const_iterator = std::vector<Difference>::const_iterator;
 
public:
    PdfDifferenceList();
 
    PdfDifferenceList(const PdfDifferenceList& rhs) = default;
    PdfDifferenceList& operator=(const PdfDifferenceList& rhs) = default;
 
    void AddDifference(unsigned char code, char32_t codePoint);
 
    void AddDifference(unsigned char code, const PdfName& name, bool explicitNames = false);
 
    bool TryGetMappedName(unsigned char code, const PdfName*& name) const;
    bool TryGetMappedName(unsigned char code, const PdfName*& name, char32_t& codePoint) const;
 
    void ToArray(PdfArray& arr) const;
 
    size_t GetCount() const;
 
    const_iterator begin() const { return m_differences.begin(); }
 
    const_iterator end() const { return m_differences.end(); }
 
private:
    void addDifference(unsigned char code, char32_t codePoint, const PdfName& name);
    bool contains(unsigned char code, const PdfName*& name, char32_t& codePoint);
 
    struct DifferenceComparatorPredicate
    {
    public:
        inline bool operator()(const Difference& diff1, const Difference& diff2) const
        {
            return diff1.Code < diff2.Code;
        }
    };
 
    List m_differences;
};
 
class PODOFO_API PdfDifferenceEncoding final : public PdfEncodingMapOneByte
{
public:
    PdfDifferenceEncoding(const PdfEncodingMapConstPtr& baseEncoding,
        const PdfDifferenceList& differences);
 
public:
    static bool TryCreateFromObject(const PdfObject& obj, const PdfFontMetrics& metrics,
        std::unique_ptr<PdfDifferenceEncoding>& encoding);
 
    static std::unique_ptr<PdfDifferenceEncoding> CreateFromObject(const PdfObject& obj, const PdfFontMetrics& metrics);
 
    static char32_t NameToCodePoint(const std::string_view& name);
 
    static PdfName CodePointToName(char32_t codePoint);
 
    inline const PdfDifferenceList& GetDifferences() const { return m_differences; }
 
protected:
    void getExportObject(PdfIndirectObjectList& objects, PdfName& name, PdfObject*& obj) const override;
    bool tryGetCharCode(char32_t codePoint, PdfCharCode& codeUnit) const override;
    bool tryGetCodePoints(const PdfCharCode& codeUnit, const unsigned* cidId, CodePointSpan& codePoints) const override;
 
private:
    void buildReverseMap();
 
private:
    PdfEncodingMapConstPtr m_baseEncoding;
    PdfDifferenceList m_differences;
    bool m_reverseMapBuilt;
    std::unordered_map<char32_t, unsigned char> m_reverseMap;
};
 
};
 
#endif // PDF_DIFFERENCE_ENCODING_H