class_name PlanetSetupHost
extends Node2D

# Instantiates the contents of a PlanetSetup onto a landed surface: one
# CapturePoint per authored point - registering/restoring conquest progress
# through GameState so re-landing on a partly-taken planet keeps its
# progress - and one enemy per authored spawn.

const CAPTURE_POINT_SCENE: PackedScene = preload("res://surface/CapturePoint.tscn")
const ENEMY_SCENE: PackedScene = preload("res://enemies/Enemy.tscn")

var setup: Resource


func apply_setup(new_setup: Resource) -> void:
	setup = new_setup
	for child in get_children():
		child.queue_free()
	if setup == null:
		return

	GameState.register_capture_points(GameState.planet_id, setup.capture_points.size(),
		GameState.planet_definition_id, int(setup.research_point_reward))
	for i in range(setup.capture_points.size()):
		_add_capture_point(i, setup.capture_points[i])
	if _garrison_is_defeated():
		return
	for spawn in setup.enemy_spawns:
		_add_enemy(spawn)


# A conquered planet stays conquered. Its garrison was destroyed to take it,
# so re-landing must not quietly restore it - the capture points already come
# back marked captured, and enemies standing on a planet the player owns read
# as the conquest having been undone.
#
# Guarded on there being capture points to take, not on the conquered flag
# alone: register_capture_points() treats a setup with none as vacuously
# conquered (see PlanetSurfaceController's note on unregistered planets), and
# a setup that authored enemies but no capture points is a garrison nobody
# can ever have beaten. Suppressing those would delete them on first sight.
func _garrison_is_defeated() -> bool:
	return not setup.capture_points.is_empty() \
		and GameState.is_planet_conquered(GameState.planet_id)


func _add_capture_point(index: int, at: Vector2) -> void:
	var point: Node = CAPTURE_POINT_SCENE.instantiate()
	point.point_index = index
	point.position = at
	add_child(point)
	if GameState.is_point_captured(GameState.planet_id, index):
		point.mark_captured()


func _add_enemy(spawn: Resource) -> void:
	var enemy: Node = ENEMY_SCENE.instantiate()
	enemy.enemy_id = spawn.enemy_id
	enemy.position = spawn.position
	add_child(enemy)