class_name StateModifierMovement
extends StateModifier

## Movement Modifiers
var horizontal_speed: float = 0
var horizontal_acceleration: float = 0
## Movement Speed Offsets (Positive or Negative)
var horizontal_speed_offset: float = 0
## Applies only if offset applies
var horizontal_speed_offset_acceleration: float = 0
var jerk_factor: float = 0

var vertical_speed: float = 0
var vertical_acceleration: float = 0
## Movement Speed Offsets (Positive or Negative)
var vertical_speed_offset: float = 0
## Applies only if offset applies
var vertical_speed_offset_acceleration: float = 0

var gravity: int = 0

## Processing Directives (help determine how the merge function works)
var direction :float = 0.0 # -1, 0, 1

enum SUB_TYPE {
	NONE, 			# Basic physics modifier just adds numbers
	## Disallows ability to surpass zero when applied to state kinematic values
	NEGATIVE_CONSTRAINT		
}

func _to_string():
	return "StateModifierMovement"

func reset():
	.reset()
	modifier_type = SUB_TYPE.NONE
	direction = 0.0
	horizontal_speed = 0
	horizontal_acceleration = 0
	## Movement Speed Offsets (Positive or Negative)
	horizontal_speed_offset = 0
	## Applies only if offset applies
	horizontal_speed_offset_acceleration = 0
	jerk_factor = 0

func copy(_copy_state: StateModifier):
	.copy(_copy_state)
	modifier_type = _copy_state.modifier_type
	if _copy_state.to_string() == "StateModifierMovement":
		_copy_state.horizontal_speed = horizontal_speed
		_copy_state.horizontal_acceleration = horizontal_acceleration

func merge(_merge_from_modifier: StateModifier):
	.merge(_merge_from_modifier)
	is_active = _merge_from_modifier.is_active
	if modifier_type != SUB_TYPE.NONE and _merge_from_modifier.modifier_type != SUB_TYPE.NONE:
		push_warning( "Attempt to push modifier type over existing one. Wut du?" )
	if _merge_from_modifier.to_string() == "StateModifierMovement":
		if modifier_type == SUB_TYPE.NONE and _merge_from_modifier.modifier_type != SUB_TYPE.NONE:
			modifier_type = _merge_from_modifier.modifier_type

		##TODO: I don't really need merge functions here? 
		match _merge_from_modifier.modifier_type:
			_:
				horizontal_speed += _merge_from_modifier.horizontal_speed
				horizontal_acceleration += _merge_from_modifier.horizontal_acceleration
				horizontal_speed_offset += _merge_from_modifier.horizontal_speed_offset
				horizontal_speed_offset_acceleration += _merge_from_modifier.horizontal_speed_offset_acceleration