# call.ludic - a player's boat or horse brought to a place: made there the first time, fetched there
# after; gone when its player leaves
function ve_add(vehicles_st: VehiclesState, kind: int, owner: int, x: float, z: float, yaw: float) -> Vehicle {
  if kind != VEHICLE_HORSE and kind != VEHICLE_BOAT { return null }
  let v = new Vehicle
  v.nid = VehicleWorld.next_id()
  v.kind = kind
  v.owner = owner
  v.yaw = yaw
  if kind == VEHICLE_HORSE {
    v.seat_h = 1.35
    v.fuel = 100.0
    v.food = 40.0
  } else {
    v.seat_h = 0.30
  }
  ve_put(v, x, z)
  ve_file(vehicles_st.ve, v)
  ve_settle(v)
  VehicleWorld.made(v)
  return v
}

# a boat's hull or a horse's legs put where the vehicle now is, at rest
function ve_settle(v: Vehicle) -> void {
  if v.kind == VEHICLE_BOAT { VehicleHull.put(v.nid, v.x, v.y, v.z, v.yaw) } else { VehicleLegs.stand(v.nid, v.x, v.y, v.z) }
}

# gone from the world: its model and its hull or legs
function ve_gone(v: Vehicle) -> void {
  if v.kind == VEHICLE_BOAT { VehicleHull.gone(v.nid) } else { VehicleLegs.gone(v.nid) }
  VehicleWorld.gone(v)
}

# at rest at (x, z): a boat on the water, a horse on the ground and tied there
function ve_put(v: Vehicle, x: float, z: float) -> void {
  v.x = x
  v.z = z
  v.speed = 0.0
  if v.kind == VEHICLE_BOAT { v.y = VehicleWorld.water(x, z) + 0.02 } else { v.y = VehicleWorld.ground(x, z) }
  v.home_x = x
  v.home_z = z
}

# Bring player pid's boat or horse to place k. False when the place is somebody else's, or it is
# being ridden. A horse faces the trough: the bay lies on its near side.
export function vehicle_call_for(vehicles_st: VehiclesState, pid: int, kind: int, k: int) -> bool {
  if not vehicles_st.ve_have_dock or k < 0 or k >= VEHICLE_PLACES { return false }
  let here = vehicle_in_place(vehicles_st, kind, k)
  let v = vehicle_of(vehicles_st, pid, kind)
  if here != null { return v != null and here.nid == v.nid }
  var yaw = vehicles_st.ve_dock_yaw
  if kind == VEHICLE_HORSE { yaw = vehicles_st.ve_rail_yaw }
  if v == null {
    let made = ve_add(vehicles_st, kind, pid, vehicle_place_x(vehicles_st, kind, k), vehicle_place_z(vehicles_st, kind, k), yaw)
    if made == null { return false }
    if pid == 0 { ve_apply_kept(vehicles_st, made) }
    return true
  }
  if v.rider >= 0 { return false }
  ve_put(v, vehicle_place_x(vehicles_st, kind, k), vehicle_place_z(vehicles_st, kind, k))
  v.yaw = yaw
  ve_settle(v)
  VehicleWorld.placed(v)
  return true
}

# a player left: their boat and horse go with them, and their places are free
export function vehicles_release(vehicles_st: mut VehiclesState, pid: int) -> void {
  if pid == 0 { return }
  let rows = ix_rows(vehicles_st.ve.owners, pid)
  while len(rows) > 0 {
    let v = ve_all(vehicles_st)[rows[len(rows) - 1]]
    ve_gone(v)
    ve_unfile(vehicles_st.ve, v)
  }
}