#include "Ball.hpp"
#include <cmath>

Ball::Ball(Point& _center, double _p, double _q) :
    Center(_center),
    surface(_center, _p, _q),
    init_h(_center.z),
    bounce_number(0),
    crt_time(0),
    A(_center.z),
    B(0),
    U(sqrt(2 * G_CTE * _center.z)),
    T(0)
{
}

void Ball::_compute_pos() {
    Center.x = A + B * crt_time - (G_CTE / 2) * crt_time * crt_time;
    surface.update_center_pos(Center);
}

void Ball::_compute_T_n() {
    double swap = T;
    T = swap + 2/G_CTE * pow(1/2, bounce_number - 2) * sqrt(2 * init_h / G_CTE);
}
void Ball::_compute_B_n() {
    B = G_CTE * T + U;
}

void Ball::_compute_A_n() {
    A = - G_CTE * T * T / 2 - (U * T);
}

void Ball::_compute_U_n() {
    U *= 1/2;
}

void Ball::update_pos(double dt) {
    crt_time += dt;
    if (crt_time >= T) {
        _compute_T_n();
        _compute_U_n();
        _compute_A_n();
        _compute_B_n();
    }
    _compute_pos();
}