#include "zbuffer.h"

#include <stdint.h>
#include <stdbool.h>
#include <gint/display.h>
#include <gint/std/stdio.h>
#include <gint/std/stdlib.h>
#include <gint/keyboard.h>
#include <gint/dma.h>
#include <gint/hardware.h>
/** size_uint32
 * taille du zbuffer exprimée en uint32_t
 * utile pour l'effacement du zbuffer sur sh3
**/
static const uint32_t size_uint32 = FE_ZB_SIZE_X*FE_ZB_SIZE_Y;

/** size_char
 * taille du zbuffer exprimée en octets
 * sera utile pour le DMA Controller
**/
static const uint32_t size_char = size_uint32*sizeof(int32_t);

/** address
 * addresse du zbuffer
**/
static int32_t* address=0;

const int32_t clearval=3000;

#define ALIGN 4
static void* buffer_malloc(uint32_t size)
{
    void *mem = malloc(size+ALIGN+sizeof(void*));
    void **ptr = (void**)((uintptr_t)(mem+ALIGN+sizeof(void*)) & ~(ALIGN-1));
    ptr[-1] = mem;
    return ptr;
}
void buffer_free(void *ptr) 
{
    free(((void**)ptr)[-1]);
}

void FE_zbuffer_clear()
{
    if (address==0)
    {
        address = buffer_malloc(size_char);
        
        if (address==0) // cas de figure où il n'y a plus assez de RAM
        {
            dclear(C_WHITE);
            dtext(1, 1, "Not enough RAM...", C_BLACK, C_NONE);
            dupdate();
            while (1==1)
                getkey();
        }
    }
    // TODO déterminer le type d'effacement
    if (isSH3())
    { // effacement CPU
        uint_fast16_t indice;
        for (indice = 0; indice < size_uint32; indice ++)
            address[indice] = clearval;
    }
    else
    { // effacement DMA
        dma_transfer(0, DMA_32B, size_uint32, &clearval, DMA_FIXED, address, DMA_INC);
    }
}

void FE_start_rendering()
{
    if (!isSH3())
        dma_transfer_wait(0);

}

bool FE_zbuffer_set_dist(int32_t x, int32_t y, int32_t dist)
{
    x %= FE_ZB_SIZE_X;
    y %= FE_ZB_SIZE_Y;
    const uint32_t indice = x * 64 + y;
    if (address[indice]>dist && dist>0)
    {
        address[indice] = dist;
        return true;
    }
    else
        return false;
}