#include "../include/drawstuff.h"
#include "../parameters.h"
#include <gint/display.h>
#include "../fixed.h"

void gint_dhline(int x1, int x2, int y, uint16_t color)
{
    if((uint)y >= 224) return;
    if(x1 > x2) swap(x1, x2);
    if(x1 >= 396 || x2 < 0) return;
    if(x1 < 0) x1 = 0;
    if(x2 >= 396) x2 = 395;

    int offset = 396 * y;

    gint_vram[offset + x1] = color;
    gint_vram[offset + x2] = color;

    x1 = x1 + (x1 & 1);
    x2 = (x2 + 1) & ~1;

    uint32_t *start = (void *)(gint_vram + offset + x1);
    uint32_t *end   = (void *)(gint_vram + offset + x2);
    uint32_t op = (color << 16) | color;

    while(end > start) *--end = op;
};


void drawGrass( int y1, int y2, uint8_t R, uint8_t G, uint8_t B, uint8_t A )
{
    uint16_t color = C_RGB(R,G,B);
    for (int y=y1; y<=y2; y++) gint_dhline( 0, SCREEN_WIDTH, y, color );
};


void drawPolygon( int x1min, int x1max, int y1, int x2min, int x2max, int y2, uint8_t R, uint8_t G, uint8_t B, uint8_t A )
{
/*
    uint16_t color = C_RGB(R,G,B);
    float Ddeltay = 1.0f / (float) (y2-y1);
    float deltay=0.0f;

    for (int y=y1; y<=y2; y++)
    {
        if (y>0 && y<SCREEN_HEIGHT)
        {
            float xmin = (float) x1min + (float) (x2min-x1min)*deltay;
            float xmax = (float) x1max + (float) (x2max-x1max)*deltay;
            gint_dhline( (int) xmin, (int) xmax, y, color );
        }
        deltay+=Ddeltay;
    }
*/
     uint16_t color = C_RGB(R,G,B);
     if (y1==y2)
     {
         gint_dhline( x1min, x1max, y1, color );
         return;
     }


    //fixed_t Ddeltay = fdiv(fix(1), fix(y2-y1));
    //fixed_t deltay = 0;
    fixed_t deltay = fdiv(fix(1), fix(y2-y1));

    fixed_t xmin = fix(x1min);
    fixed_t xmax = fix(x1max);
    fixed_t dxmin = fix(x2min-x1min);
    fixed_t dxmax = fix(x2max-x1max);

    for (int y=y1; y<=y2; y++)
    {
        if (y>0 && y<SCREEN_HEIGHT)
        {
            xmin += fmul(deltay, dxmin);
            xmax += fmul(deltay, dxmax);
            gint_dhline( fround(xmin), fround(xmax), y, color );
        }
        //deltay+=Ddeltay;
    }
};

void drawSky( void )
{
    dclear( C_RGB(0,45,255) );
};

void drawSky( int ymin, int ymax )
{
    uint16_t color = C_RGB(0,45,255);
    for(int y=ymin; y<=ymax; y++ )
        gint_dhline( 0, SCREEN_WIDTH, y, color );
};