#pragma once
#include "constants.hpp"
#include "vector2d.hpp"

// For visual simulation.
// Black pedestrians move from left to right;
// White pedestrians move from right to left.
enum Color { BLACK, WHITE };

struct Pedestrian {

  Color color;

  // $\vec{v}_{\alpha}(t)$
  Vector2d curr_vel; // v_alpha  (actual, ≤ v_max)

  // $\vec{w}_{\alpha}$
  Vector2d w; // w_alpha  (preferred, integrates force)

  // $\vec{r}_\alpha(t)$
  Vector2d curr_pos;

  // $\vec{e}_{\alpha}(t)$
  Vector2d e; // desired direction vector

  // $v_{\alpha}^{max} = 1.3 v^{0}_{\alpha}$
  double v_max;

  // $v_\alpha^0$
  double desired_v0;

  // $\vec{r}^0_\alpha$
  Vector2d destination;

  // social force
  Vector2d f_i;

  // $s_\beta^2 = (v_\beta \Delta t)^2$
  double s_b_sq;

  // $s_\beta \vec{e}_\beta = v_{\beta} \Delta t \vec{e}_{\beta}$
  Vector2d s_b_e_b;

  Pedestrian() : color(WHITE), curr_vel(0.0, 0.0), w(0.0, 0.0), curr_pos(0.0, 0.0), e(0.0, 0.0), v_max(0.0), desired_v0(0.0), destination(0.0, 0.0), f_i(0.0, 0.0), s_b_sq(0.0), s_b_e_b(0.0, 0.0) {}

  Pedestrian(Color clr, Vector2d c_v, Vector2d c_p, Vector2d e, double v_max, double desired_v0, Vector2d d, Vector2d f) : color(clr), curr_vel(c_v), w(c_v), curr_pos(c_p), e(e), v_max(v_max), desired_v0(desired_v0), destination(d), f_i(f), s_b_sq(c_v.dot(c_v) * DELTA_T_SQ), s_b_e_b(e * c_v.norm() * DELTA_T) {}
};