PdfEncodingCommon.h

// SPDX-FileCopyrightText: 2021 Francesco Pretto <ceztko@gmail.com>
// SPDX-License-Identifier: LGPL-2.0-or-later OR MPL-2.0
 
#ifndef PDF_ENCODING_COMMON_H
#define PDF_ENCODING_COMMON_H
 
#include "PdfString.h"
 
namespace PoDoFo
{
    struct PODOFO_API PdfCharCode final
    {
        unsigned Code;
 
        // RangeSize example <cd> -> 1, <00cd> -> 2
        unsigned char CodeSpaceSize;
 
        PdfCharCode();
 
        explicit PdfCharCode(unsigned code);
 
        PdfCharCode(unsigned code, unsigned char codeSpaceSize);
 
        bool operator<(const PdfCharCode& rhs) const;
 
        bool operator==(const PdfCharCode& rhs) const;
 
        bool operator!=(const PdfCharCode& rhs) const;
 
    public:
        unsigned GetByteCode(unsigned char byteIdx) const;
        void AppendTo(std::string& str) const;
        void WriteHexTo(std::string& str, bool wrap = true) const;
    };
 
    struct PODOFO_API PdfCID final
    {
        unsigned Id;
        PdfCharCode Unit;
 
        PdfCID();
 
        explicit PdfCID(unsigned id);
 
        PdfCID(unsigned id, const PdfCharCode& unit);
 
        PdfCID(const PdfCharCode& unit);
    };
 
    struct PODOFO_API PdfGID final
    {
        unsigned Id = 0;            
        unsigned MetricsId = 0;     
 
        PdfGID();
 
        PdfGID(unsigned id);
 
        PdfGID(unsigned id, unsigned metricsId);
    };
 
    struct PODOFO_API PdfCharGIDInfo
    {
        unsigned Cid = 0;           
        unsigned OrigCid = 0;       
        PdfGID Gid;                 
    };
 
    struct PODOFO_API PdfEncodingLimits final
    {
    public:
        PdfEncodingLimits(unsigned char minCodeSize, unsigned char maxCodeSize,
            const PdfCharCode& firstCharCode, const PdfCharCode& lastCharCode);
 
        PdfEncodingLimits();
 
        bool AreValid() const;
 
        bool HaveValidCodeSizeRange() const;
 
        PdfCharCode FirstChar;     // The first defined character code
        PdfCharCode LastChar;      // The last defined character code
        unsigned char MinCodeSize;
        unsigned char MaxCodeSize;
    };
 
    struct PODOFO_API PdfCIDSystemInfo final
    {
        PdfString Registry;
        PdfString Ordering;
        int Supplement = 0;
    };
 
    using codepoint = char32_t;
    using codepointview = cspan<codepoint>;
 
    class PODOFO_API CodePointSpan final
    {
    public:
        CodePointSpan();
        ~CodePointSpan();
        CodePointSpan(codepoint codepoint);
        CodePointSpan(std::initializer_list<codepoint> codepoints);
        CodePointSpan(const codepointview& view);
        CodePointSpan(const codepointview& view, codepoint codepoint);
        CodePointSpan(const CodePointSpan&);
        void CopyTo(std::vector<codepoint>& codePoints) const;
        codepointview view() const;
        unsigned GetSize() const;
        CodePointSpan& operator=(const CodePointSpan&);
        size_t size() const;
        const codepoint* data() const;
 
        operator codepointview() const;
 
        codepoint operator*() const;
 
    private:
        union
        {
            struct
            {
                uint32_t Size;
                std::array<codepoint, 3> Data;
            } m_Block;
 
            struct
            {
                uint32_t Size;
                std::unique_ptr<codepoint[]> Data;
            } m_Array;
        };
    };
 
    // Map code units -> code point(s)
    // pp. 474-475 of PdfReference 1.7 "The value of dstString can be a string of up to 512 bytes"
    using CodeUnitMap = std::unordered_map<PdfCharCode, CodePointSpan>;
}
 
namespace std
{
    template<>
    struct hash<PoDoFo::PdfCharCode>
    {
        size_t operator()(const PoDoFo::PdfCharCode& code) const noexcept
        {
            return code.CodeSpaceSize << 24 | code.Code;
        }
    };
}
 
#endif // PDF_ENCODING_COMMON_H