athena/include/LZ77/LZLookupTable.hpp

#ifndef LZLOOKUPTABLE_HPP
#define LZLOOKUPTABLE_HPP

#include <map>
#include <deque>
#include <vector>
#include <cstdint>
#include <athena/Types.hpp>

struct LZLengthOffset
{
    atUint32 length;//The number of bytes compressed
    atUint16 offset;//How far back in sliding window where bytes that match the lookAheadBuffer is located
    bool compare_equal(const LZLengthOffset& lo_pair)
    {
        return length == lo_pair.length && offset == lo_pair.offset;
    }
};

class LZLookupTable
{
public:
    LZLookupTable();
    LZLookupTable(atInt32 minimumMatch, atInt32 slidingWindow = 4096, atInt32 lookAheadWindow = 18);
    ~LZLookupTable();
    LZLengthOffset search(atUint8* curPos, const atUint8* dataBegin, const atUint8* dataEnd);
    void setLookAheadWindow(atInt32 lookAheadWindow);
private:
    typedef std::multimap<std::vector<uint8_t>, int32_t> LookupTable;
    LookupTable table;
    atInt32 m_minimumMatch;
    atInt32 m_slidingWindow;
    atInt32 m_lookAheadWindow;
    std::vector<uint8_t> m_buffer;


};

#endif // LZLOOKUPTABLE_HPP