/**
  racing module: implements the racing physics and logic.
*/

#ifndef _LCR_RACING_H
#define _LCR_RACING_H

typedef int32_t LCR_GameUnit; ///< game spatial units

#define LCR_GAME_UNIT 1024    ///< length of map square in game units

#define LCR_PHYSICS_UNIT 512  ///< length of map square for physics engine

#include "map.h"
#include "tinyphysicsengine.h"

struct
{
  TPE_World physicsWorld;
  TPE_Body carBody;
} LCR_racing;

TPE_Vec3 LCR_racingEnvironmentFunction(TPE_Vec3 point, TPE_Unit maxDist)
{
/*
  return
TPE_envHalfPlane(point,
  TPE_vec3(0,0,0),
  TPE_vec3(0,TPE_FRACTIONS_PER_UNIT,0));
*/

  return TPE_envAABoxInside(point,TPE_vec3(0,0,0),TPE_vec3(
      LCR_PHYSICS_UNIT * LCR_MAP_SIZE_BLOCKS,
      (LCR_PHYSICS_UNIT * LCR_MAP_SIZE_BLOCKS) / 2,
      LCR_PHYSICS_UNIT * LCR_MAP_SIZE_BLOCKS));

}

void LCR_racingInit(void)
{
  LCR_log("initializing racing engine");

  TPE_worldInit(&(LCR_racing.physicsWorld),
  &(LCR_racing.carBody),1,LCR_racingEnvironmentFunction);
}

void _LCR_drawPhysicsDebugPixel(uint16_t x, uint16_t y, uint8_t color)
{
  if (x > 1 && x < LCR_EFFECTIVE_RESOLUTION_X - 1 &&
      y > 1 && y < LCR_EFFECTIVE_RESOLUTION_Y - 1)
  {
    uint16_t color = color;
    color = (color << 3) | 0xf800;

    for (int j = -1; j < 2; ++j)
      for (int i = -1; i < 2; ++i)
        LCR_drawPixelXYUnsafe(x + i,y + j,color);
  }
}

void LCR_physicsDebugDraw(LCR_GameUnit camPos[3], LCR_GameUnit camRot[2],
  LCR_GameUnit camFov)
{
  TPE_Vec3 cPos, cRot, cView;

  cPos.x = (camPos[0] * LCR_PHYSICS_UNIT) / LCR_GAME_UNIT;
  cPos.y = (camPos[1] * LCR_PHYSICS_UNIT) / LCR_GAME_UNIT;
  cPos.z = (camPos[2] * LCR_PHYSICS_UNIT) / LCR_GAME_UNIT;

  cRot.x = (camRot[0] * TPE_FRACTIONS_PER_UNIT) / LCR_GAME_UNIT;
  cRot.y = (camRot[1] * TPE_FRACTIONS_PER_UNIT) / LCR_GAME_UNIT;
  cRot.z = 0; 

  cView.x = LCR_EFFECTIVE_RESOLUTION_X;
  cView.y = LCR_EFFECTIVE_RESOLUTION_Y;
  cView.z = (camFov * TPE_FRACTIONS_PER_UNIT) / LCR_GAME_UNIT;

  TPE_worldDebugDraw(&(LCR_racing.physicsWorld),_LCR_drawPhysicsDebugPixel,
    cPos,cRot,cView,16,2 * LCR_PHYSICS_UNIT);
}

#endif // guard