/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 *   Mupen64plus-rsp-hle - jpeg.c                                          *
 *   Mupen64Plus homepage: https://mupen64plus.org/                        *
 *   Copyright (C) 2012 Bobby Smiles                                       *
 *   Copyright (C) 2009 Richard Goedeken                                   *
 *   Copyright (C) 2002 Hacktarux                                          *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.          *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

#include <assert.h>
#include <stdint.h>
#include <stdlib.h>

#include "arithmetics.h"
#include "hle_external.h"
#include "hle_internal.h"
#include "memory.h"

#define SUBBLOCK_SIZE 64

typedef void (*tile_line_emitter_t)(struct hle_t* hle, const int16_t *y, const int16_t *u, uint32_t address);
typedef void (*subblock_transform_t)(int16_t *dst, const int16_t *src);

/* standard jpeg ucode decoder */
static void jpeg_decode_std(struct hle_t* hle,
                            const char *const version,
                            const subblock_transform_t transform_luma,
                            const subblock_transform_t transform_chroma,
                            const tile_line_emitter_t emit_line);

/* helper functions */
static uint8_t clamp_u8(int16_t x);
static int16_t clamp_s12(int16_t x);
static uint16_t clamp_RGBA_component(int16_t x);

/* pixel conversion & formatting */
static uint32_t GetUYVY(int16_t y1, int16_t y2, int16_t u, int16_t v);
static uint16_t GetRGBA(int16_t y, int16_t u, int16_t v);

/* tile line emitters */
static void EmitYUVTileLine(struct hle_t* hle, const int16_t *y, const int16_t *u, uint32_t address);
static void EmitRGBATileLine(struct hle_t* hle, const int16_t *y, const int16_t *u, uint32_t address);

/* macroblocks operations */
static void decode_macroblock_ob(int16_t *macroblock, int32_t *y_dc, int32_t *u_dc, int32_t *v_dc, const int16_t *qtable);
static void decode_macroblock_std(const subblock_transform_t transform_luma,
                                  const subblock_transform_t transform_chroma,
                                  int16_t *macroblock,
                                  unsigned int subblock_count,
                                  const int16_t qtables[3][SUBBLOCK_SIZE]);
static void EmitTilesMode0(struct hle_t* hle, const tile_line_emitter_t emit_line, const int16_t *macroblock, uint32_t address);
static void EmitTilesMode2(struct hle_t* hle, const tile_line_emitter_t emit_line, const int16_t *macroblock, uint32_t address);

/* subblocks operations */
static void TransposeSubBlock(int16_t *dst, const int16_t *src);
static void ZigZagSubBlock(int16_t *dst, const int16_t *src);
static void ReorderSubBlock(int16_t *dst, const int16_t *src, const unsigned int *table);
static void MultSubBlocks(int16_t *dst, const int16_t *src1, const int16_t *src2, unsigned int shift);
static void ScaleSubBlock(int16_t *dst, const int16_t *src, int16_t scale);
static void RShiftSubBlock(int16_t *dst, const int16_t *src, unsigned int shift);
static void InverseDCT1D(const float *const x, float *dst, unsigned int stride);
static void InverseDCTSubBlock(int16_t *dst, const int16_t *src);
static void RescaleYSubBlock(int16_t *dst, const int16_t *src);
static void RescaleUVSubBlock(int16_t *dst, const int16_t *src);

/* transposed dequantization table */
static const int16_t DEFAULT_QTABLE[SUBBLOCK_SIZE] = {
    16, 12, 14, 14,  18,  24,  49,  72,
    11, 12, 13, 17,  22,  35,  64,  92,
    10, 14, 16, 22,  37,  55,  78,  95,
    16, 19, 24, 29,  56,  64,  87,  98,
    24, 26, 40, 51,  68,  81, 103, 112,
    40, 58, 57, 87, 109, 104, 121, 100,
    51, 60, 69, 80, 103, 113, 120, 103,
    61, 55, 56, 62,  77,  92, 101,  99
};

/* zig-zag indices */
static const unsigned int ZIGZAG_TABLE[SUBBLOCK_SIZE] = {
     0,  1,  5,  6, 14, 15, 27, 28,
     2,  4,  7, 13, 16, 26, 29, 42,
     3,  8, 12, 17, 25, 30, 41, 43,
     9, 11, 18, 24, 31, 40, 44, 53,
    10, 19, 23, 32, 39, 45, 52, 54,
    20, 22, 33, 38, 46, 51, 55, 60,
    21, 34, 37, 47, 50, 56, 59, 61,
    35, 36, 48, 49, 57, 58, 62, 63
};

/* transposition indices */
static const unsigned int TRANSPOSE_TABLE[SUBBLOCK_SIZE] = {
    0,  8, 16, 24, 32, 40, 48, 56,
    1,  9, 17, 25, 33, 41, 49, 57,
    2, 10, 18, 26, 34, 42, 50, 58,
    3, 11, 19, 27, 35, 43, 51, 59,
    4, 12, 20, 28, 36, 44, 52, 60,
    5, 13, 21, 29, 37, 45, 53, 61,
    6, 14, 22, 30, 38, 46, 54, 62,
    7, 15, 23, 31, 39, 47, 55, 63
};



/* IDCT related constants
 * Cn = alpha * cos(n * PI / 16) (alpha is chosen such as C4 = 1) */
static const float IDCT_C3 = 1.175875602f;
static const float IDCT_C6 = 0.541196100f;
static const float IDCT_K[10] = {
     0.765366865f,   /*  C2-C6         */
    -1.847759065f,   /* -C2-C6         */
    -0.390180644f,   /*  C5-C3         */
    -1.961570561f,   /* -C5-C3         */
     1.501321110f,   /*  C1+C3-C5-C7   */
     2.053119869f,   /*  C1+C3-C5+C7   */
     3.072711027f,   /*  C1+C3+C5-C7   */
     0.298631336f,   /* -C1+C3+C5-C7   */
    -0.899976223f,   /*  C7-C3         */
    -2.562915448f    /* -C1-C3         */
};


/* global functions */

/***************************************************************************
 * JPEG decoding ucode found in Japanese exclusive version of Pokemon Stadium.
 **************************************************************************/
void jpeg_decode_PS0(struct hle_t* hle)
{
    jpeg_decode_std(hle, "PS0", RescaleYSubBlock, RescaleUVSubBlock, EmitYUVTileLine);
    rsp_break(hle, SP_STATUS_TASKDONE);
}

/***************************************************************************
 * JPEG decoding ucode found in Ocarina of Time, Pokemon Stadium 1 and
 * Pokemon Stadium 2.
 **************************************************************************/
void jpeg_decode_PS(struct hle_t* hle)
{
    jpeg_decode_std(hle, "PS", NULL, NULL, EmitRGBATileLine);
    rsp_break(hle, SP_STATUS_TASKDONE);
}

/***************************************************************************
 * JPEG decoding ucode found in Ogre Battle and Bottom of the 9th.
 **************************************************************************/
void jpeg_decode_OB(struct hle_t* hle)
{
    int16_t qtable[SUBBLOCK_SIZE];
    unsigned int mb;

    int32_t y_dc = 0;
    int32_t u_dc = 0;
    int32_t v_dc = 0;

    uint32_t           address          = *dmem_u32(hle, TASK_DATA_PTR);
    const unsigned int macroblock_count = *dmem_u32(hle, TASK_DATA_SIZE);
    const int          qscale           = *dmem_u32(hle, TASK_YIELD_DATA_SIZE);

    HleVerboseMessage(hle->user_defined,
                      "jpeg_decode_OB: *buffer=%x, #MB=%d, qscale=%d",
                      address,
                      macroblock_count,
                      qscale);

    if (qscale != 0) {
        if (qscale > 0)
            ScaleSubBlock(qtable, DEFAULT_QTABLE, qscale);
        else
            RShiftSubBlock(qtable, DEFAULT_QTABLE, -qscale);
    }

    for (mb = 0; mb < macroblock_count; ++mb) {
        int16_t macroblock[6 * SUBBLOCK_SIZE];

        dram_load_u16(hle, (uint16_t *)macroblock, address, 6 * SUBBLOCK_SIZE);
        decode_macroblock_ob(macroblock, &y_dc, &u_dc, &v_dc, (qscale != 0) ? qtable : NULL);
        EmitTilesMode2(hle, EmitYUVTileLine, macroblock, address);

        address += (2 * 6 * SUBBLOCK_SIZE);
    }
    rsp_break(hle, SP_STATUS_TASKDONE);
}


/* local functions */
static void jpeg_decode_std(struct hle_t* hle,
                            const char *const version,
                            const subblock_transform_t transform_luma,
                            const subblock_transform_t transform_chroma,
                            const tile_line_emitter_t emit_line)
{
    int16_t qtables[3][SUBBLOCK_SIZE];
    unsigned int mb;
    uint32_t address;
    uint32_t macroblock_count;
    uint32_t mode;
    uint32_t qtableY_ptr;
    uint32_t qtableU_ptr;
    uint32_t qtableV_ptr;
    unsigned int subblock_count;
    unsigned int macroblock_size;
    /* macroblock contains at most 6 subblocks */
    int16_t macroblock[6 * SUBBLOCK_SIZE];
    uint32_t data_ptr;

    if (*dmem_u32(hle, TASK_FLAGS) & 0x1) {
        HleWarnMessage(hle->user_defined,
                       "jpeg_decode_%s: task yielding not implemented", version);
        return;
    }

    data_ptr = *dmem_u32(hle, TASK_DATA_PTR);
    address          = *dram_u32(hle, data_ptr);
    macroblock_count = *dram_u32(hle, data_ptr + 4);
    mode             = *dram_u32(hle, data_ptr + 8);
    qtableY_ptr      = *dram_u32(hle, data_ptr + 12);
    qtableU_ptr      = *dram_u32(hle, data_ptr + 16);
    qtableV_ptr      = *dram_u32(hle, data_ptr + 20);

    HleVerboseMessage(hle->user_defined,
                      "jpeg_decode_%s: *buffer=%x, #MB=%d, mode=%d, *Qy=%x, *Qu=%x, *Qv=%x",
                      version,
                      address,
                      macroblock_count,
                      mode,
                      qtableY_ptr,
                      qtableU_ptr,
                      qtableV_ptr);

    if (mode != 0 && mode != 2) {
        HleWarnMessage(hle->user_defined,
                       "jpeg_decode_%s: invalid mode %d", version, mode);
        return;
    }

    subblock_count = mode + 4;
    macroblock_size = subblock_count * SUBBLOCK_SIZE;

    dram_load_u16(hle, (uint16_t *)qtables[0], qtableY_ptr, SUBBLOCK_SIZE);
    dram_load_u16(hle, (uint16_t *)qtables[1], qtableU_ptr, SUBBLOCK_SIZE);
    dram_load_u16(hle, (uint16_t *)qtables[2], qtableV_ptr, SUBBLOCK_SIZE);

    for (mb = 0; mb < macroblock_count; ++mb) {
        dram_load_u16(hle, (uint16_t *)macroblock, address, macroblock_size);
        decode_macroblock_std(transform_luma, transform_chroma,
                              macroblock, subblock_count, (const int16_t (*)[SUBBLOCK_SIZE])qtables);

        if (mode == 0)
            EmitTilesMode0(hle, emit_line, macroblock, address);
        else
            EmitTilesMode2(hle, emit_line, macroblock, address);

        address += 2 * macroblock_size;
    }
}

static uint8_t clamp_u8(int16_t x)
{
    return (x & (0xff00)) ? ((-x) >> 15) & 0xff : x;
}

static int16_t clamp_s12(int16_t x)
{
    if (x < -0x800)
        x = -0x800;
    else if (x > 0x7f0)
        x = 0x7f0;
    return x;
}

static uint16_t clamp_RGBA_component(int16_t x)
{
    if (x > 0xff0)
        x = 0xff0;
    else if (x < 0)
        x = 0;
    return (x & 0xf80);
}

static uint32_t GetUYVY(int16_t y1, int16_t y2, int16_t u, int16_t v)
{
    return (uint32_t)clamp_u8(u)  << 24 |
           (uint32_t)clamp_u8(y1) << 16 |
           (uint32_t)clamp_u8(v)  << 8 |
           (uint32_t)clamp_u8(y2);
}

static uint16_t GetRGBA(int16_t y, int16_t u, int16_t v)
{
    const float fY = (float)y + 2048.0f;
    const float fU = (float)u;
    const float fV = (float)v;

    const uint16_t r = clamp_RGBA_component((int16_t)(fY               + 1.4025 * fV));
    const uint16_t g = clamp_RGBA_component((int16_t)(fY - 0.3443 * fU - 0.7144 * fV));
    const uint16_t b = clamp_RGBA_component((int16_t)(fY + 1.7729 * fU));

    return (r << 4) | (g >> 1) | (b >> 6) | 1;
}

static void EmitYUVTileLine(struct hle_t* hle, const int16_t *y, const int16_t *u, uint32_t address)
{
    uint32_t uyvy[8];

    const int16_t *const v  = u + SUBBLOCK_SIZE;
    const int16_t *const y2 = y + SUBBLOCK_SIZE;

    uyvy[0] = GetUYVY(y[0],  y[1],  u[0], v[0]);
    uyvy[1] = GetUYVY(y[2],  y[3],  u[1], v[1]);
    uyvy[2] = GetUYVY(y[4],  y[5],  u[2], v[2]);
    uyvy[3] = GetUYVY(y[6],  y[7],  u[3], v[3]);
    uyvy[4] = GetUYVY(y2[0], y2[1], u[4], v[4]);
    uyvy[5] = GetUYVY(y2[2], y2[3], u[5], v[5]);
    uyvy[6] = GetUYVY(y2[4], y2[5], u[6], v[6]);
    uyvy[7] = GetUYVY(y2[6], y2[7], u[7], v[7]);

    dram_store_u32(hle, uyvy, address, 8);
}

static void EmitRGBATileLine(struct hle_t* hle, const int16_t *y, const int16_t *u, uint32_t address)
{
    uint16_t rgba[16];

    const int16_t *const v  = u + SUBBLOCK_SIZE;
    const int16_t *const y2 = y + SUBBLOCK_SIZE;

    rgba[0]  = GetRGBA(y[0],  u[0], v[0]);
    rgba[1]  = GetRGBA(y[1],  u[0], v[0]);
    rgba[2]  = GetRGBA(y[2],  u[1], v[1]);
    rgba[3]  = GetRGBA(y[3],  u[1], v[1]);
    rgba[4]  = GetRGBA(y[4],  u[2], v[2]);
    rgba[5]  = GetRGBA(y[5],  u[2], v[2]);
    rgba[6]  = GetRGBA(y[6],  u[3], v[3]);
    rgba[7]  = GetRGBA(y[7],  u[3], v[3]);
    rgba[8]  = GetRGBA(y2[0], u[4], v[4]);
    rgba[9]  = GetRGBA(y2[1], u[4], v[4]);
    rgba[10] = GetRGBA(y2[2], u[5], v[5]);
    rgba[11] = GetRGBA(y2[3], u[5], v[5]);
    rgba[12] = GetRGBA(y2[4], u[6], v[6]);
    rgba[13] = GetRGBA(y2[5], u[6], v[6]);
    rgba[14] = GetRGBA(y2[6], u[7], v[7]);
    rgba[15] = GetRGBA(y2[7], u[7], v[7]);

    dram_store_u16(hle, rgba, address, 16);
}

static void EmitTilesMode0(struct hle_t* hle, const tile_line_emitter_t emit_line, const int16_t *macroblock, uint32_t address)
{
    unsigned int i;

    unsigned int y_offset = 0;
    unsigned int u_offset = 2 * SUBBLOCK_SIZE;

    for (i = 0; i < 8; ++i) {
        emit_line(hle, &macroblock[y_offset], &macroblock[u_offset], address);

        y_offset += 8;
        u_offset += 8;
        address += 32;
    }
}

static void EmitTilesMode2(struct hle_t* hle, const tile_line_emitter_t emit_line, const int16_t *macroblock, uint32_t address)
{
    unsigned int i;

    unsigned int y_offset = 0;
    unsigned int u_offset = 4 * SUBBLOCK_SIZE;

    for (i = 0; i < 8; ++i) {
        emit_line(hle, &macroblock[y_offset],     &macroblock[u_offset], address);
        emit_line(hle, &macroblock[y_offset + 8], &macroblock[u_offset], address + 32);

        y_offset += (i == 3) ? SUBBLOCK_SIZE + 16 : 16;
        u_offset += 8;
        address += 64;
    }
}

static void decode_macroblock_ob(int16_t *macroblock, int32_t *y_dc, int32_t *u_dc, int32_t *v_dc, const int16_t *qtable)
{
    int sb;

    for (sb = 0; sb < 6; ++sb) {
        int16_t tmp_sb[SUBBLOCK_SIZE];

        /* update DC */
        int32_t dc = (int32_t)macroblock[0];
        switch (sb) {
        case 0:
        case 1:
        case 2:
        case 3:
            *y_dc += dc;
            macroblock[0] = *y_dc & 0xffff;
            break;
        case 4:
            *u_dc += dc;
            macroblock[0] = *u_dc & 0xffff;
            break;
        case 5:
            *v_dc += dc;
            macroblock[0] = *v_dc & 0xffff;
            break;
        }

        ZigZagSubBlock(tmp_sb, macroblock);
        if (qtable != NULL)
            MultSubBlocks(tmp_sb, tmp_sb, qtable, 0);
        TransposeSubBlock(macroblock, tmp_sb);
        InverseDCTSubBlock(macroblock, macroblock);

        macroblock += SUBBLOCK_SIZE;
    }
}

static void decode_macroblock_std(const subblock_transform_t transform_luma,
                                  const subblock_transform_t transform_chroma,
                                  int16_t *macroblock,
                                  unsigned int subblock_count,
                                  const int16_t qtables[3][SUBBLOCK_SIZE])
{
    unsigned int sb;
    unsigned int q = 0;

    for (sb = 0; sb < subblock_count; ++sb) {
        int16_t tmp_sb[SUBBLOCK_SIZE];
        const int isChromaSubBlock = (subblock_count - sb <= 2);

        if (isChromaSubBlock)
            ++q;

        MultSubBlocks(macroblock, macroblock, qtables[q], 4);
        ZigZagSubBlock(tmp_sb, macroblock);
        InverseDCTSubBlock(macroblock, tmp_sb);

        if (isChromaSubBlock) {
            if (transform_chroma != NULL)
                transform_chroma(macroblock, macroblock);
        } else {
            if (transform_luma != NULL)
                transform_luma(macroblock, macroblock);
        }

        macroblock += SUBBLOCK_SIZE;
    }
}

static void TransposeSubBlock(int16_t *dst, const int16_t *src)
{
    ReorderSubBlock(dst, src, TRANSPOSE_TABLE);
}

static void ZigZagSubBlock(int16_t *dst, const int16_t *src)
{
    ReorderSubBlock(dst, src, ZIGZAG_TABLE);
}

static void ReorderSubBlock(int16_t *dst, const int16_t *src, const unsigned int *table)
{
    unsigned int i;

    /* source and destination sublocks cannot overlap */
    assert(labs(dst - src) >= SUBBLOCK_SIZE);

    for (i = 0; i < SUBBLOCK_SIZE; ++i)
        dst[i] = src[table[i]];
}

static void MultSubBlocks(int16_t *dst, const int16_t *src1, const int16_t *src2, unsigned int shift)
{
    unsigned int i;

    for (i = 0; i < SUBBLOCK_SIZE; ++i) {
        int32_t v = src1[i] * src2[i];
        dst[i] = clamp_s16(v) << shift;
    }
}

static void ScaleSubBlock(int16_t *dst, const int16_t *src, int16_t scale)
{
    unsigned int i;

    for (i = 0; i < SUBBLOCK_SIZE; ++i) {
        int32_t v = src[i] * scale;
        dst[i] = clamp_s16(v);
    }
}

static void RShiftSubBlock(int16_t *dst, const int16_t *src, unsigned int shift)
{
    unsigned int i;

    for (i = 0; i < SUBBLOCK_SIZE; ++i)
        dst[i] = src[i] >> shift;
}

/***************************************************************************
 * Fast 2D IDCT using separable formulation and normalization
 * Computations use single precision floats
 * Implementation based on Wikipedia :
 * http://fr.wikipedia.org/wiki/Transform%C3%A9e_en_cosinus_discr%C3%A8te
 **************************************************************************/
static void InverseDCT1D(const float *const x, float *dst, unsigned int stride)
{
    float e[4];
    float f[4];
    float x26, x1357, x15, x37, x17, x35;

    x15   = IDCT_K[2] * (x[1] + x[5]);
    x37   = IDCT_K[3] * (x[3] + x[7]);
    x17   = IDCT_K[8] * (x[1] + x[7]);
    x35   = IDCT_K[9] * (x[3] + x[5]);
    x1357 = IDCT_C3   * (x[1] + x[3] + x[5] + x[7]);
    x26   = IDCT_C6   * (x[2] + x[6]);

    f[0] = x[0] + x[4];
    f[1] = x[0] - x[4];
    f[2] = x26  + IDCT_K[0] * x[2];
    f[3] = x26  + IDCT_K[1] * x[6];

    e[0] = x1357 + x15 + IDCT_K[4] * x[1] + x17;
    e[1] = x1357 + x37 + IDCT_K[6] * x[3] + x35;
    e[2] = x1357 + x15 + IDCT_K[5] * x[5] + x35;
    e[3] = x1357 + x37 + IDCT_K[7] * x[7] + x17;

    *dst = f[0] + f[2] + e[0];
    dst += stride;
    *dst = f[1] + f[3] + e[1];
    dst += stride;
    *dst = f[1] - f[3] + e[2];
    dst += stride;
    *dst = f[0] - f[2] + e[3];
    dst += stride;
    *dst = f[0] - f[2] - e[3];
    dst += stride;
    *dst = f[1] - f[3] - e[2];
    dst += stride;
    *dst = f[1] + f[3] - e[1];
    dst += stride;
    *dst = f[0] + f[2] - e[0];
}

static void InverseDCTSubBlock(int16_t *dst, const int16_t *src)
{
    float x[8];
    float block[SUBBLOCK_SIZE];
    unsigned int i, j;

    /* idct 1d on rows (+transposition) */
    for (i = 0; i < 8; ++i) {
        for (j = 0; j < 8; ++j)
            x[j] = (float)src[i * 8 + j];

        InverseDCT1D(x, &block[i], 8);
    }

    /* idct 1d on columns (thanks to previous transposition) */
    for (i = 0; i < 8; ++i) {
        InverseDCT1D(&block[i * 8], x, 1);

        /* C4 = 1 normalization implies a division by 8 */
        for (j = 0; j < 8; ++j)
            dst[i + j * 8] = (int16_t)x[j] >> 3;
    }
}

static void RescaleYSubBlock(int16_t *dst, const int16_t *src)
{
    unsigned int i;

    for (i = 0; i < SUBBLOCK_SIZE; ++i)
        dst[i] = (((uint32_t)(clamp_s12(src[i]) + 0x800) * 0xdb0) >> 16) + 0x10;
}

static void RescaleUVSubBlock(int16_t *dst, const int16_t *src)
{
    unsigned int i;

    for (i = 0; i < SUBBLOCK_SIZE; ++i)
        dst[i] = (((int)clamp_s12(src[i]) * 0xe00) >> 16) + 0x80;
}

