/*
 * optenc.h
 *
 * Defines for the optimal encoder
 */


// lookahead
#define LOOK            1024

// don't-care threshold for tree structure
#define BREAK_LENGTH    50

#define NUM_DIRECT_LOOKUP_TABLE_ELEMENTS    65536

// see stdenc.h for comments on these values
#define OPT_ENCODER_LIT_DIST_BUFFER_SIZE    65536
#define OPT_ENCODER_MAX_ITEMS                65534



// For the optimal parser

typedef unsigned long numbits_t;

typedef struct
{
    ULONG        link;
    ULONG        path;
    numbits_t    numbits;
} t_decision_node;



// Optimal encoder context

typedef struct optimal_encoder
{
    BYTE                     window[2*WINDOW_SIZE + MAX_MATCH + 4];
    t_decision_node         decision_node[LOOK+MAX_MATCH+16];
    t_match_pos                matchpos_table[MAX_MATCH+1];
    t_search_node            search_left[2*WINDOW_SIZE];
    t_search_node            search_right[2*WINDOW_SIZE];
    t_search_node            search_tree_root[65536];

    // recording buffer for recording literals and distances
    BYTE                    lit_dist_buffer[OPT_ENCODER_LIT_DIST_BUFFER_SIZE];
    unsigned long            recording_bitbuf;
    unsigned long            recording_bitcount;
    BYTE *                  recording_bufptr;

    unsigned int            next_tree_update;

    short                    recording_dist_tree_table[REC_DISTANCES_DECODING_TABLE_SIZE];
    short                    recording_dist_tree_left[2*MAX_DIST_TREE_ELEMENTS];
    short                    recording_dist_tree_right[2*MAX_DIST_TREE_ELEMENTS];
    BYTE                    recording_dist_tree_len[MAX_DIST_TREE_ELEMENTS];
    USHORT                  recording_dist_tree_code[MAX_DIST_TREE_ELEMENTS];

    short                    recording_literal_tree_table[REC_LITERALS_DECODING_TABLE_SIZE];
    short                    recording_literal_tree_left[2*MAX_LITERAL_TREE_ELEMENTS];
    short                    recording_literal_tree_right[2*MAX_LITERAL_TREE_ELEMENTS];
    BYTE                    recording_literal_tree_len[MAX_LITERAL_TREE_ELEMENTS];
    USHORT                  recording_literal_tree_code[MAX_LITERAL_TREE_ELEMENTS];

    // literal trees
    unsigned short          literal_tree_freq[2*MAX_LITERAL_TREE_ELEMENTS];
    unsigned short            literal_tree_code[MAX_LITERAL_TREE_ELEMENTS];
    BYTE                    literal_tree_len[MAX_LITERAL_TREE_ELEMENTS];

    // dist trees
    unsigned short          dist_tree_freq[2*MAX_DIST_TREE_ELEMENTS];
    unsigned short            dist_tree_code[MAX_DIST_TREE_ELEMENTS];
    BYTE                    dist_tree_len[MAX_DIST_TREE_ELEMENTS];

} t_optimal_encoder;