/*
    zstd_internal - common functions to include
    Header File for include
    Copyright (C) 2014-2016, Yann Collet.

    BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are
    met:
    * Redistributions of source code must retain the above copyright
    notice, this list of conditions and the following disclaimer.
    * Redistributions in binary form must reproduce the above
    copyright notice, this list of conditions and the following disclaimer
    in the documentation and/or other materials provided with the
    distribution.
    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

    You can contact the author at :
    - zstd homepage : https://www.zstd.net
*/
#ifndef ZSTD_CCOMMON_H_MODULE
#define ZSTD_CCOMMON_H_MODULE

/*-*************************************
*  Dependencies
***************************************/
#include "mem.h"
#include "error_private.h"
#include "zstd_static.h"


/*-*************************************
*  Common macros
***************************************/
#define MIN(a,b) ((a)<(b) ? (a) : (b))
#define MAX(a,b) ((a)>(b) ? (a) : (b))


/*-*************************************
*  Common constants
***************************************/
#define ZSTD_OPT_DEBUG 0     // 3 = compression stats;  5 = check encoded sequences;  9 = full logs
#include <stdio.h>
#if defined(ZSTD_OPT_DEBUG) && ZSTD_OPT_DEBUG>=9
    #define ZSTD_LOG_PARSER(...) printf(__VA_ARGS__)
    #define ZSTD_LOG_ENCODE(...) printf(__VA_ARGS__)
    #define ZSTD_LOG_BLOCK(...) printf(__VA_ARGS__)
#else
    #define ZSTD_LOG_PARSER(...)
    #define ZSTD_LOG_ENCODE(...)
    #define ZSTD_LOG_BLOCK(...)
#endif

#define ZSTD_OPT_NUM    (1<<12)
#define ZSTD_DICT_MAGIC  0xEC30A436

#define ZSTD_REP_NUM    3
#define ZSTD_REP_INIT   ZSTD_REP_NUM
#define ZSTD_REP_MOVE   (ZSTD_REP_NUM-1)

#define KB *(1 <<10)
#define MB *(1 <<20)
#define GB *(1U<<30)

#define BIT7 128
#define BIT6  64
#define BIT5  32
#define BIT4  16
#define BIT1   2
#define BIT0   1

#define ZSTD_WINDOWLOG_ABSOLUTEMIN 12
static const size_t ZSTD_fcs_fieldSize[4] = { 0, 1, 2, 8 };

#define ZSTD_BLOCKHEADERSIZE 3   /* because C standard does not allow a static const value to be defined using another static const value .... :( */
static const size_t ZSTD_blockHeaderSize = ZSTD_BLOCKHEADERSIZE;
typedef enum { bt_compressed, bt_raw, bt_rle, bt_end } blockType_t;

#define MIN_SEQUENCES_SIZE 1 /* nbSeq==0 */
#define MIN_CBLOCK_SIZE (1 /*litCSize*/ + 1 /* RLE or RAW */ + MIN_SEQUENCES_SIZE /* nbSeq==0 */)   /* for a non-null block */

#define HufLog 12

#define IS_HUF 0
#define IS_PCH 1
#define IS_RAW 2
#define IS_RLE 3

#define LONGNBSEQ 0x7F00

#define MINMATCH 3
#define EQUAL_READ32 4
#define REPCODE_STARTVALUE 1

#define Litbits  8
#define MaxLit ((1<<Litbits) - 1)
#define MaxML  52
#define MaxLL  35
#define MaxOff 28
#define MaxSeq MAX(MaxLL, MaxML)   /* Assumption : MaxOff < MaxLL,MaxML */
#define MLFSELog    9
#define LLFSELog    9
#define OffFSELog   8

#define FSE_ENCODING_RAW     0
#define FSE_ENCODING_RLE     1
#define FSE_ENCODING_STATIC  2
#define FSE_ENCODING_DYNAMIC 3

static const U32 LL_bits[MaxLL+1] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                                      1, 1, 1, 1, 2, 2, 3, 3, 4, 6, 7, 8, 9,10,11,12,
                                     13,14,15,16 };
static const S16 LL_defaultNorm[MaxLL+1] = { 4, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1,
                                             2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 1, 1, 1, 1, 1,
                                            -1,-1,-1,-1 };
static const U32 LL_defaultNormLog = 6;

static const U32 ML_bits[MaxML+1] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                                      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                                      1, 1, 1, 1, 2, 2, 3, 3, 4, 4, 5, 7, 8, 9,10,11,
                                     12,13,14,15,16 };
static const S16 ML_defaultNorm[MaxML+1] = { 1, 4, 3, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1,
                                             1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
                                             1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,-1,-1,
                                            -1,-1,-1,-1,-1 };
static const U32 ML_defaultNormLog = 6;

static const S16 OF_defaultNorm[MaxOff+1] = { 1, 1, 1, 1, 1, 1, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1,
                                              1, 1, 1, 1, 1, 1, 1, 1,-1,-1,-1,-1,-1 };
static const U32 OF_defaultNormLog = 5;


/*-*******************************************
*  Shared functions to include for inlining
*********************************************/
static void ZSTD_copy8(void* dst, const void* src) { memcpy(dst, src, 8); }
#define COPY8(d,s) { ZSTD_copy8(d,s); d+=8; s+=8; }

/*! ZSTD_wildcopy() :
*   custom version of memcpy(), can copy up to 7 bytes too many (8 bytes if length==0) */
#define WILDCOPY_OVERLENGTH 8
MEM_STATIC void ZSTD_wildcopy(void* dst, const void* src, size_t length)
{
    const BYTE* ip = (const BYTE*)src;
    BYTE* op = (BYTE*)dst;
    BYTE* const oend = op + length;
    do
        COPY8(op, ip)
    while (op < oend);
}

MEM_STATIC unsigned ZSTD_highbit(U32 val)
{
#   if defined(_MSC_VER)   /* Visual */
    unsigned long r=0;
    _BitScanReverse(&r, val);
    return (unsigned)r;
#   elif defined(__GNUC__) && (__GNUC__ >= 3)   /* GCC Intrinsic */
    return 31 - __builtin_clz(val);
#   else   /* Software version */
    static const int DeBruijnClz[32] = { 0, 9, 1, 10, 13, 21, 2, 29, 11, 14, 16, 18, 22, 25, 3, 30, 8, 12, 20, 28, 15, 17, 24, 7, 19, 27, 23, 6, 26, 5, 4, 31 };
    U32 v = val;
    int r;
    v |= v >> 1;
    v |= v >> 2;
    v |= v >> 4;
    v |= v >> 8;
    v |= v >> 16;
    r = DeBruijnClz[(U32)(v * 0x07C4ACDDU) >> 27];
    return r;
#   endif
}


/*-*******************************************
*  Private interfaces
*********************************************/
typedef struct {
    U32 off;
    U32 len;
} ZSTD_match_t;

typedef struct {
    U32 price;
    U32 off;
    U32 mlen;
    U32 litlen;
    U32 rep[ZSTD_REP_INIT];
} ZSTD_optimal_t;

#if ZSTD_OPT_DEBUG == 3
    #include ".debug/zstd_stats.h"
#else
    typedef struct { U32  unused; } ZSTD_stats_t;
    MEM_STATIC void ZSTD_statsPrint(ZSTD_stats_t* stats, U32 searchLength) { (void)stats; (void)searchLength; };
    MEM_STATIC void ZSTD_statsInit(ZSTD_stats_t* stats) { (void)stats; };
    MEM_STATIC void ZSTD_statsResetFreqs(ZSTD_stats_t* stats) { (void)stats; };
    MEM_STATIC void ZSTD_statsUpdatePrices(ZSTD_stats_t* stats, size_t litLength, const BYTE* literals, size_t offset, size_t matchLength) { (void)stats; (void)litLength; (void)literals; (void)offset; (void)matchLength; };
#endif

typedef struct {
    void* buffer;
    U32*  offsetStart;
    U32*  offset;
    BYTE* offCodeStart;
    BYTE* litStart;
    BYTE* lit;
    U16*  litLengthStart;
    U16*  litLength;
    BYTE* llCodeStart;
    U16*  matchLengthStart;
    U16*  matchLength;
    BYTE* mlCodeStart;
    U32   longLengthID;   /* 0 == no longLength; 1 == Lit.longLength; 2 == Match.longLength; */
    U32   longLengthPos;
    /* opt */
    ZSTD_optimal_t* priceTable;
    ZSTD_match_t* matchTable;
    U32* matchLengthFreq;
    U32* litLengthFreq;
    U32* litFreq;
    U32* offCodeFreq;
    U32  matchLengthSum;
    U32  matchSum;
    U32  litLengthSum;
    U32  litSum;
    U32  offCodeSum;
    U32  log2matchLengthSum;
    U32  log2matchSum;
    U32  log2litLengthSum;
    U32  log2litSum;
    U32  log2offCodeSum;
    U32  factor;
    U32  cachedPrice;
    U32  cachedLitLength;
    const BYTE* cachedLiterals;
    ZSTD_stats_t stats;
} seqStore_t;

const seqStore_t* ZSTD_getSeqStore(const ZSTD_CCtx* ctx);
void ZSTD_seqToCodes(const seqStore_t* seqStorePtr, size_t const nbSeq);


#endif   /* ZSTD_CCOMMON_H_MODULE */