extends RefCounted
## Retains a living target, then applies the public formation target policy.

func choose(unit, combatants: Array):
	if is_instance_valid(unit.target) and unit.target.alive:
		if unit.distance_to_unit(unit.target) <= 10.0:
			return unit.target
	var candidates: Array = []
	var nearby: Array = []
	for other in combatants:
		if not other.alive or other.team_id != unit.team_id or other.is_attacker == unit.is_attacker:
			continue
		candidates.append(other)
		if unit.distance_to_unit(other) <= 8.0:
			nearby.append(other)
	if candidates.is_empty():
		return null
	var policy = 0 if unit.is_attacker or nearby.is_empty() else unit.target_policy
	if not nearby.is_empty():
		candidates = nearby
	candidates.sort_custom(func(a, b):
		var av = unit.distance_to_unit(a)
		var bv = unit.distance_to_unit(b)
		if policy == 1:
			av = a.hp
			bv = b.hp
		elif policy == 2:
			av = -a.max_hp
			bv = -b.max_hp
		return a.uid < b.uid if is_equal_approx(av, bv) else av < bv
	)
	return candidates[0]