package game

type effect interface {
	apply(*LocalState)
	end(*LocalState)
}

type dynamicEffect struct {
	_apply func(*LocalState)
	_end   func(*LocalState)
}

func (e *dynamicEffect) apply(s *LocalState) {
	e._apply(s)
}

func (e *dynamicEffect) end(s *LocalState) {
	e._end(s)
}

func newAdjustmentEffect(adjust func(Permanent, int), u *Unit, delta int) effect {
	apply := func(*LocalState) { adjust(u, delta) }
	end := func(*LocalState) { adjust(u, -delta) }
	return &dynamicEffect{apply, end}
}

func newMeleeModificationEffect(u *Unit, delta int) effect {
	return newAdjustmentEffect(adjustMelee, u, delta)
}

func newAttackModificationEffect(u *Unit, delta int) effect {
	return newAdjustmentEffect(adjustAttack, u, delta)
}

func newMovementModificationEffect(u *Unit, delta int) effect {
	return newAdjustmentEffect(adjustMovement, u, delta)
}

func newHealthModificationEffect(u *Unit, delta int) effect {
	return newAdjustmentEffect(adjustHealth, u, delta)
}

func newTmpEffect(p Permanent, effect string) effect {
	apply := func(*LocalState) { p.addTmpEffect(effect) }
	end := func(*LocalState) { p.removeTmpEffect(effect) }
	return &dynamicEffect{apply, end}
}