extends SceneTree

# Headless gameplay test: run with
#   godot --headless -s res://tests/test_conquered_planet_clear.gd
# A planet's garrison was destroyed to take it, so it must not be standing
# there again the next time the player lands.
#
# #211 made the garrison the whole of conquest: killing the last defender
# takes the planet, and there are no capture points beside them any more.
#
# Covers:
#   A. an unconquered planet lays out its authored enemies, as before
#   B. killing the last of them conquers it, and re-landing places none
#   C. a setup with NO enemies counts as vacuously conquered - there is
#      nothing there to beat
#   D. a half-cleared planet the player left comes back whole, and its count
#      with it, rather than falling to a single kill on the next visit

const PLANET_KEY: String = "test_conquered_planet_clear"
const OPEN_PLANET_KEY: String = "test_conquered_planet_clear_open"
const LEFT_PLANET_KEY: String = "test_conquered_planet_clear_left"

var game_state: Node
var host_scene: PackedScene
var stage: int = 0
var elapsed: float = 0.0


func _initialize() -> void:
	game_state = root.get_node("GameState")
	game_state.planet_capture.clear()
	host_scene = load("res://surface/PlanetSetupHost.tscn")


func _process(delta: float) -> bool:
	elapsed += delta
	if stage == 0:
		# One frame of grace so the autoload is fully up, same as the other
		# scene-driven tests.
		if elapsed < 0.1:
			return false

		# --- A. unconquered: the garrison is there ---------------------------
		game_state.planet_id = PLANET_KEY
		game_state.planet_definition_id = "rocky"
		var setup: Resource = _make_setup(3)
		var enemies: int = _apply_and_count_enemies(setup)
		if enemies != 3:
			return _fail("an unconquered planet placed %d of its 3 authored enemies" % enemies)
		if game_state.is_planet_conquered(PLANET_KEY):
			return _fail("a planet with 3 defenders standing reported itself conquered")
		print("unconquered planet: 3 enemies placed")

		# --- B. the last kill takes it, and it stays taken -------------------
		game_state.mark_garrison_enemy_destroyed(PLANET_KEY)
		game_state.mark_garrison_enemy_destroyed(PLANET_KEY)
		if game_state.is_planet_conquered(PLANET_KEY):
			return _fail("the planet fell with a defender still standing")
		game_state.mark_garrison_enemy_destroyed(PLANET_KEY)
		if not game_state.is_planet_conquered(PLANET_KEY):
			return _fail("killing the whole garrison did not conquer the planet")

		var remaining: int = _apply_and_count_enemies(setup)
		if remaining != 0:
			return _fail("re-landing on a conquered planet placed %d enemies" % remaining)
		print("conquered planet: last kill took it, re-landing places nobody")

		# --- C. nothing to fight is nothing to take --------------------------
		game_state.planet_id = OPEN_PLANET_KEY
		var open_setup: Resource = _make_setup(0)
		var open_enemies: int = _apply_and_count_enemies(open_setup)
		if not game_state.is_planet_conquered(OPEN_PLANET_KEY):
			return _fail("a setup with no enemies was expected to be vacuously conquered")
		if open_enemies != 0:
			return _fail("a setup authoring no enemies placed %d" % open_enemies)
		print("setup with no garrison: vacuously conquered, nobody placed")

		# --- D. leaving mid-fight does not bank the kills --------------------
		# The garrison is re-placed in full on the next landing, so its count
		# has to start again with it - otherwise a planet left at one-from-
		# clear would fall to a single kill against three fresh defenders.
		game_state.planet_id = LEFT_PLANET_KEY
		var left_setup: Resource = _make_setup(3)
		_apply_and_count_enemies(left_setup)
		game_state.mark_garrison_enemy_destroyed(LEFT_PLANET_KEY)
		game_state.mark_garrison_enemy_destroyed(LEFT_PLANET_KEY)
		var returned: int = _apply_and_count_enemies(left_setup)
		if returned != 3:
			return _fail("returning to a half-cleared planet placed %d of 3 defenders" % returned)
		game_state.mark_garrison_enemy_destroyed(LEFT_PLANET_KEY)
		if game_state.is_planet_conquered(LEFT_PLANET_KEY):
			return _fail("one kill took a planet defended by three - the count did not reset with the garrison")
		print("returning mid-fight: the garrison and its count both start again")

		print("TEST_CONQUERED_PLANET_CLEAR: PASS")
		quit(0)
		return true
	return false


func _make_setup(enemy_count: int) -> Resource:
	var setup: Resource = load("res://surface/PlanetSetup.gd").new()
	setup.setup_id = "in_memory"
	setup.surface_profile_id = "rocky"
	var spawn_script: Script = load("res://surface/PlanetSetupSpawn.gd")
	for i in range(enemy_count):
		var spawn: Resource = spawn_script.new()
		spawn.enemy_id = "chaser"
		spawn.position = Vector2(0.0, 200.0 * float(i + 1))
		setup.enemy_spawns.append(spawn)
	return setup


func _apply_and_count_enemies(setup: Resource) -> int:
	var host: Node = host_scene.instantiate()
	root.add_child(host)
	host.apply_setup(setup)
	var count: int = _count_enemies(host)
	host.free()
	return count


# Counted by group rather than by script or node name: that is how everything
# else in the game finds enemies, so this cannot pass while the real hunters
# see something different.
func _count_enemies(host: Node) -> int:
	var count: int = 0
	for child in host.get_children():
		if child.is_in_group("enemies"):
			count += 1
	return count


func _fail(message: String) -> bool:
	print("TEST_CONQUERED_PLANET_CLEAR: FAIL (%s)" % message)
	quit(1)
	return true