#include "triangle.h"

#include "display.h"

// TODO: Create implementation for triangle.h functions
int compare_vec2_t(const void* a, const void* b) {
    const vec2_t* arg1 = (const vec2_t*)a;
    const vec2_t* arg2 = (const vec2_t*)b;
    if (arg1->y < arg2->y) return -1;
    if (arg1->y > arg2->y) return 1;
    return 0;
}

void fill_flat_bottom_triangle(triangle_t triangle) {

}

void fill_flat_top_triangle(triangle_t triangle) {

}

vec2_t triangle_midpoint(triangle_t triangle) {
    // sort by y
    int temp = 0, min_idx = 0, mid_idx = 1, max_idx = 2;

    if (triangle.points[min_idx].y > triangle.points[mid_idx].y) {
        temp = min_idx; min_idx = mid_idx; mid_idx = temp;
    }
    if (triangle.points[min_idx].y > triangle.points[max_idx].y) {
        temp = min_idx; min_idx = max_idx; max_idx = temp;
    }
    if (triangle.points[mid_idx].y > triangle.points[max_idx].y) {
        temp = mid_idx; mid_idx = max_idx; max_idx = temp;
    }

    // check for division by zero
    if (triangle.points[max_idx].y == triangle.points[min_idx].y) {
        // Degenerate case, return something reasonable
        return triangle.points[mid_idx];  // or some fallback
    }

    vec2_t midpoint;
    midpoint.y = triangle.points[mid_idx].y;
    midpoint.x = (((triangle.points[max_idx].x - triangle.points[min_idx].x) * (triangle.points[mid_idx].y - triangle.points[min_idx].y)) / (triangle.points[max_idx].y - triangle.points[min_idx].y)) + triangle.points[min_idx].x;

    triangle_t flat_top, flat_bottom;

    flat_bottom.points[0] = triangle.points[min_idx];
    flat_bottom.points[1] = triangle.points[mid_idx];
    flat_bottom.points[2] = midpoint;

    flat_top.points[0] = triangle.points[mid_idx];
    flat_top.points[1] = triangle.points[max_idx];
    flat_top.points[2] = midpoint;

    draw_triangle(flat_bottom, 0xFF00FF00);
    draw_triangle(flat_top, 0xF0000FF);

    return midpoint;

}