#include "draw.h"
#include "stdafx.h"

#define RGB32(r, g, b) static_cast<uint32_t>((((static_cast<uint32_t>(b) << 8) | g) << 8) | r)


void put_pixel32(SDL_Surface* surface, int x, int y, Uint32 pixel)
{
    assert(NULL != surface);
    assert(x < SCREEN_WIDTH);
    assert(y < SCREEN_HEIGHT);

    Uint32* pixels = (Uint32*)surface->pixels;
    pixels[(y * surface->w) + x] = pixel;
}

Uint32 get_pixel32(SDL_Surface* surface, int x, int y)
{
    assert(NULL != surface);
    assert(x < SCREEN_WIDTH);
    assert(y < SCREEN_HEIGHT);

    Uint32* pixels = (Uint32*)surface->pixels;
    return pixels[(y * surface->w) + x];
}


void draw_horizontal_line(SDL_Surface* s, int start_x, int final_x, int y, int color)
{
    int hatch_frequncy = (SCREEN_WIDTH / (AMOUNT_HATCHS + 1));
    for (int x = start_x; x < final_x; x++)
    {
        put_pixel32(s, x, y, color);
    }
}

void draw_vertical_line(SDL_Surface* s, int start_y, int final_y, int x, int color)
{
    int max = (start_y > final_y) ? start_y : final_y;
    int min = (start_y < final_y) ? start_y : final_y;
    for (int y = min; y < max; y++)
    {
        put_pixel32(s, x, y, color);
    }
}

void draw_horizontal_hatches(SDL_Surface* s, int start_y, int final_y, int x)
{
    int hatch_frequncy = (SCREEN_HEIGHT / (AMOUNT_HATCHS + 1));
    for (int y = start_y; y < final_y; y++)
    {
        if (y % hatch_frequncy == 0)
            draw_horizontal_line(s, x - HATCH_LEN, x + HATCH_LEN, y, RGB(255, 255, 255));
    }
}

void draw_vertical_hatches(SDL_Surface* s, int start_x, int final_x, int y)
{
    int hatch_frequncy = (SCREEN_HEIGHT / (AMOUNT_HATCHS + 1));
    for (int x = start_x; x < final_x; x++)
    {
        if (x % hatch_frequncy == 0)
            draw_vertical_line(s, y - HATCH_LEN, y + HATCH_LEN, x, RGB(255, 255, 255));
    }
}

void draw_angular_line(SDL_Surface* s, int start_x, int final_x, int start_y, int final_y, int color)
{
    int amount_iterations = 8;
    int delta_y = (final_y - start_y) / amount_iterations;
    int delta_x = (final_x - start_x) / amount_iterations;

    for (int i = 0; i < amount_iterations; i++)
    {
        put_pixel32(s, start_x, start_y, color);
        start_x += delta_x;
        start_y += delta_y;
    }
}

void draw_first_graphic(SDL_Surface* s)
{
    int cur_x;
    int cur_y;
    int prev_x = SCREEN_WIDTH / 2;
    int prev_y = SCREEN_HEIGHT / 2;
    for (int x = 0; x < 15; x++)
    {
        cur_x = (SCREEN_WIDTH / 2) - x * 6;
        cur_y = (SCREEN_HEIGHT / 2) - (3 * x * x);
        put_pixel32(s, cur_x, cur_y, RGB(240, 0, 178));

        draw_angular_line(s, prev_x, cur_x, prev_y, cur_y, RGB(240, 0, 178));
        prev_x = cur_x;
        prev_y = cur_y;
    }


    prev_x = SCREEN_WIDTH / 2;
    prev_y = SCREEN_HEIGHT / 2;
    for (int x = 0; x < 15; x++)
    {
        cur_x = (SCREEN_WIDTH / 2) + x * 6;
        cur_y = (SCREEN_HEIGHT / 2) - (3 * x * x);
        put_pixel32(s, cur_x, cur_y, RGB(240, 0, 178));

        draw_angular_line(s, prev_x, cur_x, prev_y, cur_y, RGB(240, 0, 178));
        prev_x = cur_x;
        prev_y = cur_y;
    }
}

void draw_second_graphic(SDL_Surface* s)
{
    draw_horizontal_line(s, 0, 450, 500, RGB(0, 0, 178));
    draw_horizontal_line(s, 490, 1000, 500, RGB(0, 0, 178));

    draw_vertical_line(s, 470, 0, 470, RGB(0, 0, 178));
    draw_vertical_line(s, 470, 0, 480, RGB(0, 0, 178));

    int y = 470;
    for (int x = 470; x > 450;) {
        put_pixel32(s, x, y, RGB(0, 0, 178));
        if (x < 460) {
            x -= 2;
            y += 1;
        }
        else {
            y += 2;
            x -= 1;
        }
    }

    y = 470;
    for (int x = 480; x < 490;) {
        put_pixel32(s, x, y, RGB(0, 0, 178));
        if (x < 485) {
            x += 1;
            y += 3;
        }
        else {
            y += 2;
            x += 2;
        }
    }
}


void draw(SDL_Surface* s, SDL_Renderer* gRenderer)
{
    int y;
    int x;

    draw_horizontal_line(s, 0, SCREEN_WIDTH, SCREEN_HEIGHT / 2, RGB(255, 255, 255));
    draw_vertical_line(s, 0, SCREEN_HEIGHT, SCREEN_WIDTH / 2, RGB(255, 255, 255));
    draw_horizontal_hatches(s, 0, SCREEN_HEIGHT, SCREEN_WIDTH / 2);
    draw_vertical_hatches(s, 0, SCREEN_HEIGHT, SCREEN_WIDTH / 2);

    draw_first_graphic(s);
    draw_second_graphic(s);
}