namespace Oriels;

public class Board {
  // velocity button controls
  // "center off mass" thrust vector steering

  Mesh meshCube = Mesh.Cube;

  public bool goofy = false;

  public Vec3 front, back, pos, dir, vector;
  public float vel;

  float length = 1.5f;
  public Board() {
    front = new Vec3(0, 0, -1) * length / 2;
    back = new Vec3(0, 0, 1) * length / 2;
    dir = new Vec3(0, 0, -1);
    vel = 0;
  }

  public void Frame() {
    // tilt steer ("back wheel" turns *rudder)
    // button velocity controls
    Con con = goofy ? Mono.inst.rig.rCon : Mono.inst.rig.lCon;
    float accel = con.device.trigger;
    float deccel = con.device.grip;
    float lean = Mono.inst.rig.LocalPos(Mono.inst.rig.Head.position).x;

    // float length = 1.5f;
    float drag = 0.1f;
    float speed = 4f;
    float brake = 12f;
    float tight = 60f;


    // velocity
    vel *= 1f - (drag * Time.Stepf);
    vel += accel * speed * Time.Stepf;
    vel = MathF.Max(vel - deccel * brake * Time.Stepf, 0);

    // steering
    vector = Quat.LookDir(dir) * Quat.FromAngles(0, lean * tight, 0) * Vec3.Forward;
    back += vector * vel * Time.Stepf;
    dir = (front - back).Normalized;

    front = back + dir * length;
    pos = Vec3.Lerp(front, back, 0.5f);


    Mono.inst.rig.pos = pos;
    Mono.inst.rig.ori = Quat.LookDir(dir);

    // hover
    // if (rig.lCon.gripBtn.held) {
    //   rig.pos.y = pid.Update(rig.LocalPos(rig.Head.position).y);
    // }


    meshCube.Draw(Material.Default,
      Matrix.TRS(
        Mono.inst.rig.FloorCenter,
        Quat.LookDir(dir),
        new Vec3(0.05f, 0.2f, 0.2f)
      )
    );

    // mini board in hand for debugging
    // meshCube.Draw(Material.Default,
    //   Matrix.TRS(
    //     rig.rCon.pos,
    //     board.ori,
    //     new Vec3(0.4f, 0.1f, reach * 2) * 0.1f
    //   )
    // );
    // // front wheel
    // meshCube.Draw(Material.Default,
    //   Matrix.TRS(
    //     rig.rCon.pos + board.dir * reach * 0.1f,
    //     Quat.LookDir(frontDir),
    //     new Vec3(0.05f, 0.2f, 0.2f) * 0.1f
    //   )
    // );





    // // pillars to hover through
    // // spawn in front every 1m away from last
    // if (Vec3.Distance(pos, lastSpawnPos) > 1f) {
    //   // odd or even
    //   float chirality = pillarIndex % 2 == 0 ? 1f : -1f;
    //   pillars[pillarIndex] = pos + Quat.LookDir(dir) * new Vec3(chirality * 8 * Mono.inst.noise.uvalue, 0, -24);

    //   lastSpawnPos = pos;

    //   pillarIndex++;
    //   if (pillarIndex >= pillars.Length) { pillarIndex = 0; }
    // }

    // for (int i = 0; i < pillars.Length; i++) {
    //   meshCube.Draw(Material.Default,
    //     Matrix.TRS(
    //       pillars[i],
    //       Quat.Identity,
    //       new Vec3(0.1f, 20f, 0.1f)
    //     )
    //   );
    // }
  }
  // Vec3[] pillars = new Vec3[64];
  // int pillarIndex = 0;
  // Vec3 lastSpawnPos = Vec3.Zero;
}