extends Player

class_name DownhillAutoscrollerPlayer

export var min_speed : float = 3
export var max_speed : float = 16
export var player_initiated_acceleration : float = 8

var last_contacted_map_elem_type : int = Constants.MapElemType.SQUARE

func process_unit(delta, time_elapsed : float):
	# always be movin'
	facing = Constants.Direction.RIGHT
	actions[Constants.ActionType.MOVE] = true
	
	# Fine tune the player's speed
	
	if get_current_action() == Constants.UnitCurrentAction.RECOILING:
		target_move_speed = min_speed
	else:
		# override player input so that leftward movement is deceleration,
		# right movement is acceleration
		if scene.input_table[Constants.PlayerInput.LEFT][scene.I_T_PRESSED]:
			target_move_speed = move_toward(target_move_speed, min_speed, player_initiated_acceleration * delta)
		else:
			if not get_condition(Constants.UnitCondition.IS_ON_GROUND, true):
				if (target_move_speed < Constants.UNIT_TYPE_MOVE_SPEEDS[unit_type]
				and scene.input_table[Constants.PlayerInput.RIGHT][scene.I_T_PRESSED]):
					target_move_speed = move_toward(target_move_speed, Constants.UNIT_TYPE_MOVE_SPEEDS[unit_type], player_initiated_acceleration * delta)
			else:
				# shallow slope: arctan(.5) = 27 degrees, sin(27) = 0.45
				# steep slope: sin(45) = 0.71
				var ground_influenced_acceleration = 0
				var is_decel : bool = false
				if (last_contacted_map_elem_type == Constants.MapElemType.SMALL_SLOPE_RIGHT_1
				or last_contacted_map_elem_type == Constants.MapElemType.SMALL_SLOPE_RIGHT_2
				or last_contacted_map_elem_type == Constants.MapElemType.SMALL_SLOPE_LEFT_1
				or last_contacted_map_elem_type == Constants.MapElemType.SMALL_SLOPE_LEFT_2):
					ground_influenced_acceleration = Constants.GRAVITY * 0.45
					if (last_contacted_map_elem_type == Constants.MapElemType.SMALL_SLOPE_LEFT_1
					or last_contacted_map_elem_type == Constants.MapElemType.SMALL_SLOPE_LEFT_2):
						is_decel = true
				elif (last_contacted_map_elem_type == Constants.MapElemType.SLOPE_RIGHT
				or last_contacted_map_elem_type == Constants.MapElemType.SLOPE_LEFT):
					ground_influenced_acceleration = Constants.GRAVITY * 0.71
					if last_contacted_map_elem_type == Constants.MapElemType.SLOPE_LEFT:
						is_decel = true
				if is_decel or ground_influenced_acceleration == 0:
					var end_speed
					if ground_influenced_acceleration == 0:
						# flat ground
						if scene.input_table[Constants.PlayerInput.RIGHT][scene.I_T_PRESSED]:
							end_speed = max(target_move_speed, Constants.UNIT_TYPE_MOVE_SPEEDS[unit_type])
						else:
							end_speed = target_move_speed
					else:
						# incline
						if scene.input_table[Constants.PlayerInput.RIGHT][scene.I_T_PRESSED]:
							end_speed = Constants.UNIT_TYPE_MOVE_SPEEDS[unit_type]
						else:
							end_speed = min_speed
					if target_move_speed < end_speed:
						target_move_speed = move_toward(target_move_speed, end_speed, player_initiated_acceleration * delta)
					else:
						target_move_speed = move_toward(target_move_speed, end_speed, ground_influenced_acceleration * delta)
				else:
					var acceleration = ground_influenced_acceleration
					if scene.input_table[Constants.PlayerInput.RIGHT][scene.I_T_PRESSED]:
						acceleration = max(acceleration, player_initiated_acceleration)
					if target_move_speed < max_speed:
						target_move_speed = move_toward(target_move_speed, max_speed, acceleration * delta)

	.process_unit(delta, time_elapsed)

# treat all collisions as right-side collisions
func hit(dir : int):
	# Unit.gd implementation override
	hit_queued = true
	hit_dir = Constants.Direction.RIGHT
	
	# Player.gd implementation
	set_unit_condition_with_timer(Constants.UnitCondition.IS_INVINCIBLE)
	start_flash()
	set_action(Constants.ActionType.RECOIL)
	set_current_action(Constants.UnitCurrentAction.RECOILING)
	set_unit_condition(Constants.UnitCondition.MOVING_STATUS, Constants.UnitMovingStatus.IDLE)

# override super class's RECOIL_PUSHBACK
func handle_recoil():
	if not hit_queued:
		return
	hit_queued = false
	# skip recoil pushback logic, since target_move_speed is already
	# set to min_speed