/***************************************************************************
*                                                                          *
* Project64-video - A Nintendo 64 gfx plugin.                              *
* http://www.pj64-emu.com/                                                 *
* Copyright (C) 2017 Project64. All rights reserved.                       *
* Copyright (C) 2007 Hiroshi Morii                                         *
* Copyright (C) 2003 Rice1964                                              *
*                                                                          *
* License:                                                                 *
* GNU/GPLv2 http://www.gnu.org/licenses/gpl-2.0.html                       *
* version 2 of the License, or (at your option) any later version.         *
*                                                                          *
****************************************************************************/

#include "TxUtil.h"
#include "TxDbg.h"
#include <zlib/zlib.h>
#include <malloc.h>
#include <stdlib.h>
#ifdef _WIN32
#include <windows.h>
#endif

/*
 * External libraries
 ******************************************************************************/
TxLoadLib::TxLoadLib()
{
    _tx_compress_dxtn = tx_compress_dxtn;
    _tx_compress_fxt1 = fxt1_encode;
}

TxLoadLib::~TxLoadLib()
{
}

fxtCompressTexFuncExt TxLoadLib::getfxtCompressTexFuncExt()
{
    return _tx_compress_fxt1;
}

dxtCompressTexFuncExt TxLoadLib::getdxtCompressTexFuncExt()
{
    return _tx_compress_dxtn;
}

/*
 * Utilities
 ******************************************************************************/
uint32 TxUtil::checksumTx(uint8 *src, int width, int height, uint16 format)
{
    int dataSize = sizeofTx(width, height, format);

    /* for now we use adler32 if something else is better
     * we can simply swtich later
     */
     /* return (dataSize ? Adler32(src, dataSize, 1) : 0); */

     /* zlib crc32 */
    return (dataSize ? crc32(crc32(0L, Z_NULL, 0), src, dataSize) : 0);
}

int TxUtil::sizeofTx(int width, int height, uint16 format)
{
    int dataSize = 0;

    /* a lookup table for the shifts would be better */
    switch (format) {
    case GR_TEXFMT_ARGB_CMP_FXT1:
        dataSize = (((width + 0x7) & ~0x7) * ((height + 0x3) & ~0x3)) >> 1;
        break;
    case GR_TEXFMT_ARGB_CMP_DXT1:
        dataSize = (((width + 0x3) & ~0x3) * ((height + 0x3) & ~0x3)) >> 1;
        break;
    case GR_TEXFMT_ARGB_CMP_DXT3:
    case GR_TEXFMT_ARGB_CMP_DXT5:
        dataSize = ((width + 0x3) & ~0x3) * ((height + 0x3) & ~0x3);
        break;
    case GR_TEXFMT_ALPHA_INTENSITY_44:
    case GR_TEXFMT_ALPHA_8:
    case GR_TEXFMT_INTENSITY_8:
    case GR_TEXFMT_P_8:
        dataSize = width * height;
        break;
    case GR_TEXFMT_ARGB_4444:
    case GR_TEXFMT_ARGB_1555:
    case GR_TEXFMT_RGB_565:
    case GR_TEXFMT_ALPHA_INTENSITY_88:
        dataSize = (width * height) << 1;
        break;
    case GR_TEXFMT_ARGB_8888:
        dataSize = (width * height) << 2;
        break;
    default:
        /* unsupported format */
        DBG_INFO(80, "Error: cannot get size. unsupported gfmt:%x\n", format);
        ;
    }

    return dataSize;
}

uint32 TxUtil::checksum(uint8 *src, int width, int height, int size, int rowStride)
{
    /* Rice CRC32 for now. We can switch this to Jabo MD5 or
     * any other custom checksum.
     * TODO: use *_HIRESTEXTURE option. */

    if (!src) return 0;

    return RiceCRC32(src, width, height, size, rowStride);
}

uint64_t TxUtil::checksum64(uint8 *src, int width, int height, int size, int rowStride, uint8 *palette)
{
    /* Rice CRC32 for now. We can switch this to Jabo MD5 or
     * any other custom checksum.
     * TODO: use *_HIRESTEXTURE option. */
     /* Returned value is 64bits: hi=palette crc32 low=texture crc32 */

    if (!src) return 0;

    uint64_t crc64Ret = 0;

    if (palette)
    {
        uint32 crc32 = 0, cimax = 0;
        switch (size & 0xff)
        {
        case 1:
            if (RiceCRC32_CI8(src, width, height, size, rowStride, &crc32, &cimax))
            {
                crc64Ret = (uint64_t)RiceCRC32(palette, cimax + 1, 1, 2, 512);
                crc64Ret <<= 32;
                crc64Ret |= (uint64_t)crc32;
            }
            break;
        case 0:
            if (RiceCRC32_CI4(src, width, height, size, rowStride, &crc32, &cimax))
            {
                crc64Ret = (uint64_t)RiceCRC32(palette, cimax + 1, 1, 2, 32);
                crc64Ret <<= 32;
                crc64Ret |= (uint64_t)crc32;
            }
        }
    }
    if (!crc64Ret)
    {
        crc64Ret = (uint64_t)RiceCRC32(src, width, height, size, rowStride);
    }

    return crc64Ret;
}

/*
** Computes Adler32 checksum for a stream of data.
**
** From the specification found in RFC 1950: (ZLIB Compressed Data Format
** Specification version 3.3)
**
** ADLER32 (Adler-32 checksum) This contains a checksum value of the
** uncompressed data (excluding any dictionary data) computed according to
** Adler-32 algorithm. This algorithm is a 32-bit extension and improvement
** of the Fletcher algorithm, used in the ITU-T X.224 / ISO 8073 standard.
**
** Adler-32 is composed of two sums accumulated per byte: s1 is the sum of
** all bytes, s2 is the sum of all s1 values. Both sums are done modulo
** 65521. s1 is initialized to 1, s2 to zero. The Adler-32 checksum is stored
** as s2*65536 + s1 in most-significant-byte first (network) order.
**
** 8.2. The Adler-32 algorithm
**
** The Adler-32 algorithm is much faster than the CRC32 algorithm yet still
** provides an extremely low probability of undetected errors.
**
** The modulo on unsigned long accumulators can be delayed for 5552 bytes,
** so the modulo operation time is negligible. If the bytes are a, b, c,
** the second sum is 3a + 2b + c + 3, and so is position and order sensitive,
** unlike the first sum, which is just a checksum. That 65521 is prime is
** important to avoid a possible large class of two-byte errors that leave
** the check unchanged. (The Fletcher checksum uses 255, which is not prime
** and which also makes the Fletcher check insensitive to single byte
** changes 0 <-> 255.)
**
** The sum s1 is initialized to 1 instead of zero to make the length of
** the sequence part of s2, so that the length does not have to be checked
** separately. (Any sequence of zeroes has a Fletcher checksum of zero.)
*/

uint32 TxUtil::Adler32(const uint8* data, int Len, uint32 dwAdler32)
{
    /* zlib adler32 */
    return adler32(dwAdler32, data, Len);
}

uint32 TxUtil::Adler32(const uint8* src, int width, int height, int size, int rowStride)
{
    int i;
    uint32 ret = 1;
    uint32 width_in_bytes = width * size;

    for (i = 0; i < height; i++)
    {
        ret = Adler32(src, width_in_bytes, ret);
        src += rowStride;
    }

    return ret;
}

// rotate left
template<class T> static T __ROL__(T value, unsigned int count)
{
    const unsigned int nbits = sizeof(T) * 8;
    count %= nbits;

    T high = value >> (nbits - count);
    value <<= count;
    value |= high;
    return value;
}

/* Rice CRC32 for hires texture packs */
/* NOTE: The following is used in Glide64 to calculate the CRC32
 * for Rice hires texture packs.
 *
 * BYTE* addr = (BYTE*)(gfx.RDRAM +
 *                     rdp.addr[rdp.tiles(tile).t_mem] +
 *                     (rdp.tiles(tile).ul_t * bpl) +
 *                     (((rdp.tiles(tile).ul_s<<rdp.tiles(tile).size)+1)>>1));
 * RiceCRC32(addr,
 *          rdp.tiles(tile).width,
 *          rdp.tiles(tile).height,
 *          (unsigned short)(rdp.tiles(tile).format << 8 | rdp.tiles(tile).size),
 *          bpl);
 */
uint32 TxUtil::RiceCRC32(const uint8* src, int width, int height, int size, int rowStride)
{
    const uint8_t *row;
    uint32_t crc32Ret;
    int cur_height;
    uint32_t pos;
    uint32_t word;
    uint32_t word_hash = 0;
    uint32_t tmp;
    const uint32_t bytes_per_width = ((width << size) + 1) >> 1;

    row = src;
    crc32Ret = 0;

    for (cur_height = height - 1; cur_height >= 0; cur_height--)
    {
        for (pos = bytes_per_width - 4; pos < 0x80000000u; pos -= 4)
        {
            word = *(uint32_t *)&row[pos];
            word_hash = pos ^ word;
            tmp = __ROL__(crc32Ret, 4);
            crc32Ret = word_hash + tmp;
        }
        crc32Ret += cur_height ^ word_hash;
        row += rowStride;
    }
    return crc32Ret;
}

bool TxUtil::RiceCRC32_CI4(const uint8* src, int width, int height, int size, int rowStride, uint32* crc32, uint32* cimax)
{
    const uint8_t *row;
    uint32_t crc32Ret;
    uint32_t cimaxRet;
    int cur_height;
    uint32_t pos;
    uint32_t word;
    uint32_t word_hash = 0;
    uint32_t tmp;
    const uint32_t bytes_per_width = ((width << size) + 1) >> 1;

    row = src;
    crc32Ret = 0;
    cimaxRet = 0;

    for (cur_height = height - 1; cur_height >= 0; cur_height--)
    {
        for (pos = bytes_per_width - 4; pos < 0x80000000u; pos -= 4)
        {
            word = *(uint32_t *)&row[pos];
            if (cimaxRet != 15)
            {
                if ((word & 0xF) >= cimaxRet)
                    cimaxRet = word & 0xF;
                if ((uint32_t)((uint8_t)word >> 4) >= cimaxRet)
                    cimaxRet = (uint8_t)word >> 4;
                if (((word >> 8) & 0xF) >= cimaxRet)
                    cimaxRet = (word >> 8) & 0xF;
                if ((uint32_t)((uint16_t)word >> 12) >= cimaxRet)
                    cimaxRet = (uint16_t)word >> 12;
                if (((word >> 16) & 0xF) >= cimaxRet)
                    cimaxRet = (word >> 16) & 0xF;
                if (((word >> 20) & 0xF) >= cimaxRet)
                    cimaxRet = (word >> 20) & 0xF;
                if (((word >> 24) & 0xF) >= cimaxRet)
                    cimaxRet = (word >> 24) & 0xF;
                if (word >> 28 >= cimaxRet)
                    cimaxRet = word >> 28;
            }
            word_hash = pos ^ word;
            tmp = __ROL__(crc32Ret, 4);
            crc32Ret = word_hash + tmp;
        }
        crc32Ret += cur_height ^ word_hash;
        row += rowStride;
    }
    *crc32 = crc32Ret;
    *cimax = cimaxRet;
    return 1;
}

bool TxUtil::RiceCRC32_CI8(const uint8* src, int width, int height, int size, int rowStride, uint32* crc32, uint32* cimax)
{
    const uint8_t *row;
    uint32_t crc32Ret;
    uint32_t cimaxRet;
    int cur_height;
    uint32_t pos;
    uint32_t word;
    uint32_t word_hash = 0;
    uint32_t tmp;
    const uint32_t bytes_per_width = ((width << size) + 1) >> 1;

    row = src;
    crc32Ret = 0;
    cimaxRet = 0;

    for (cur_height = height - 1; cur_height >= 0; cur_height--)
    {
        for (pos = bytes_per_width - 4; pos < 0x80000000u; pos -= 4)
        {
            word = *(uint32_t *)&row[pos];
            if (cimaxRet != 255)
            {
                if ((uint8_t)word >= cimaxRet)
                    cimaxRet = (uint8_t)word;
                if ((uint32_t)((uint16_t)word >> 8) >= cimaxRet)
                    cimaxRet = (uint16_t)word >> 8;
                if (((word >> 16) & 0xFF) >= cimaxRet)
                    cimaxRet = (word >> 16) & 0xFF;
                if (word >> 24 >= cimaxRet)
                    cimaxRet = word >> 24;
            }
            word_hash = pos ^ word;
            tmp = __ROL__(crc32Ret, 4);
            crc32Ret = word_hash + tmp;
        }
        crc32Ret += cur_height ^ word_hash;
        row += rowStride;
    }
    *crc32 = crc32Ret;
    *cimax = cimaxRet;
    return 1;
}

int TxUtil::log2(int num)
{
#if defined(__GNUC__)
    return __builtin_ctz(num);
#elif defined(_MSC_VER) && _MSC_VER >= 1400
    uint32_t i;
    _BitScanForward((unsigned long *)&i, num);
    return i;
#elif defined(__MSC__)
    __asm {
        mov eax, dword ptr[num];
        bsr eax, eax;
        mov dword ptr[i], eax;
    }
#else
    switch (num) {
    case 1:    return 0;
    case 2:    return 1;
    case 4:    return 2;
    case 8:    return 3;
    case 16:   return 4;
    case 32:   return 5;
    case 64:   return 6;
    case 128:  return 7;
    case 256:  return 8;
    case 512:  return 9;
    case 1024:  return 10;
    case 2048:  return 11;
    }
#endif
}

int TxUtil::grLodLog2(int w, int h)
{
    return (w >= h ? log2(w) : log2(h));
}

int TxUtil::grAspectRatioLog2(int w, int h)
{
    return (w >= h ? log2(w / h) : -log2(h / w));
}

int TxUtil::getNumberofProcessors()
{
    int numcore = 1, ret;

#ifdef _WIN32
#ifndef _SC_NPROCESSORS_ONLN
    SYSTEM_INFO info;
    GetSystemInfo(&info);
#define sysconf(a) info.dwNumberOfProcessors
#define _SC_NPROCESSORS_ONLN
#endif
#endif
#ifdef _SC_NPROCESSORS_ONLN
    ret = sysconf(_SC_NPROCESSORS_CONF);
    if (ret >= 1) {
        numcore = ret;
    }
    ret = sysconf(_SC_NPROCESSORS_ONLN);
    if (ret < 1) {
        numcore = ret;
    }
#endif

    return numcore;
}

/*
 * Memory buffers for texture manipulations
 ******************************************************************************/
TxMemBuf::TxMemBuf()
{
    int i;
    for (i = 0; i < 2; i++) {
        _tex[i] = NULL;
        _size[i] = 0;
    }
}

TxMemBuf::~TxMemBuf()
{
    shutdown();
}

bool TxMemBuf::init(int maxwidth, int maxheight)
{
    int i;
    for (i = 0; i < 2; i++)
    {
        if (!_tex[i])
        {
            _tex[i] = (uint8 *)malloc(maxwidth * maxheight * 4);
            _size[i] = maxwidth * maxheight * 4;
        }

        if (!_tex[i])
        {
            shutdown();
            return 0;
        }
    }
    return 1;
}

void TxMemBuf::shutdown()
{
    int i;
    for (i = 0; i < 2; i++) {
        if (_tex[i]) free(_tex[i]);
        _tex[i] = NULL;
        _size[i] = 0;
    }
}

uint8* TxMemBuf::get(unsigned int num)
{
    return ((num < 2) ? _tex[num] : NULL);
}

uint32 TxMemBuf::size_of(unsigned int num)
{
    return ((num < 2) ? _size[num] : 0);
}