#include "picture.h"

Picture *Picture_new(SDL_Renderer *rend,
    int x, int y, int w, int h, uint32_t color) {
    
    Picture *p = calloc(1, sizeof(Picture));

    p->x1 = x;
    p->x2 = x + w;
    p->y1 = y;
    p->y2 = y + h;
    p->w = w;
    p->h = h;
    p->color = color;
    p->s = (w + 7) / 8 * 8;

    p->pixels = malloc(p->s * h * sizeof(uint32_t));
    p->surface = SDL_CreateRGBSurfaceWithFormatFrom(
        p->pixels, w, h, 32, p->s * sizeof(uint32_t),
        SDL_PIXELFORMAT_RGBA32);

    Picture_render(p, rend);
    return p;
}

typedef uint32_t uint32_8 __attribute__ ((vector_size (8 * sizeof(uint32_t))));

void Picture_render(Picture *p, SDL_Renderer *rend) {
    int w = p->w, h = p->h;
    uint32_8 c = p->color - (uint32_8){};
    uint32_8 y = p->y1 - (uint32_8){};
    for (int j = 0, r = 0; j < h; j++, y += 1) {
        uint32_8 x = p->x1 + (uint32_8){0, 1, 2, 3, 4, 5, 6, 7};
        for (int i = 0; i < w; i += 8,r += 8, x += 8) {
            uint32_8 z = (x ^ y) % 9;
            uint32_8 f = (z==0) & c;
            memcpy(&p->pixels[r], (uint32_t*)&f, sizeof(f));
        }
    }
    if (p->texture) SDL_DestroyTexture(p->texture);
    p->texture = SDL_CreateTextureFromSurface(rend, p->surface);
    SDL_SetTextureBlendMode(p->texture, SDL_BLENDMODE_NONE);
}

void Picture_move(Picture *p, int x, int y) {
    p->x1 += x;
    p->x2 += x;
    p->y1 += y;
    p->y2 += y;
}