extends SceneTree

var failures: Array[String] = []


func _init() -> void:
	_run.call_deferred()


func _run() -> void:
	_check_phase0_files()
	_check_directories()
	_check_project_settings()
	_check_phase1_files()
	_finish()


func _check_phase0_files() -> void:
	_expect(_file_contains("res://.gitignore", ".godot/"), ".gitignore should ignore .godot/")
	_expect(_file_contains("res://.gitignore", ".DS_Store"), ".gitignore should ignore .DS_Store")
	_expect(_file_contains("res://.gitignore", "*.import.tmp"), ".gitignore should ignore *.import.tmp")
	_expect(FileAccess.file_exists("res://README.md"), "README.md should exist")
	_expect(_file_contains("res://docs/decisions.md", "body collision audit"), "docs/decisions.md should record the body collision audit")
	_expect(_file_contains("res://docs/decisions.md", "player_body"), "body collision audit should record player_body layer decision")
	_expect(_file_contains("res://docs/decisions.md", "enemy_body"), "body collision audit should record enemy_body layer decision")


func _check_directories() -> void:
	for dir_path: String in [
		"res://autoload",
		"res://scripts/resolvers",
		"res://resources/actions",
		"res://resources/actions/enemies",
		"res://resources/effects",
		"res://resources/charts",
		"res://scenes/characters",
		"res://scenes/chart",
		"res://scenes/combat",
		"res://scenes/components",
		"res://scenes/enemies",
		"res://scenes/ground",
		"res://scenes/main",
		"res://scenes/stage",
		"res://scenes/ui",
		"res://assets/art",
		"res://assets/audio",
		"res://assets/ui",
		"res://tools",
		"res://tests",
		"res://docs",
	]:
		_expect(DirAccess.open(dir_path) != null, "%s should exist" % dir_path)
	_expect(DirAccess.open("res://resources/effects/time_phase") != null, "resources/effects/time_phase should contain implemented time-phase effects")


func _check_project_settings() -> void:
	var expected_layers := {
		"layer_names/2d_physics/layer_1": "world",
		"layer_names/2d_physics/layer_2": "player_hurtbox",
		"layer_names/2d_physics/layer_3": "enemy_hurtbox",
		"layer_names/2d_physics/layer_4": "player_hitbox",
		"layer_names/2d_physics/layer_5": "enemy_hitbox",
		"layer_names/2d_physics/layer_6": "player_body",
		"layer_names/2d_physics/layer_7": "enemy_body",
	}
	for key: String in expected_layers:
		_expect(ProjectSettings.has_setting(key), "%s should be configured" % key)
		if ProjectSettings.has_setting(key):
			_expect_equal(str(ProjectSettings.get_setting(key)), expected_layers[key], "%s name" % key)

	for autoload_name: String in ["EventBus", "RhythmManager"]:
		var key := "autoload/%s" % autoload_name
		_expect(ProjectSettings.has_setting(key), "%s should be registered as an autoload" % autoload_name)
	if ProjectSettings.has_setting("autoload/EventBus"):
		_expect(str(ProjectSettings.get_setting("autoload/EventBus")).contains("res://autoload/event_bus.gd"), "EventBus autoload path")
	if ProjectSettings.has_setting("autoload/RhythmManager"):
		_expect(str(ProjectSettings.get_setting("autoload/RhythmManager")).contains("res://autoload/rhythm_manager.gd"), "RhythmManager autoload path")

	_expect_action_unbound("move_left")
	_expect_action_unbound("move_right")
	_expect_action_key("combo_a", KEY_A)
	_expect_action_key("combo_d", KEY_D)
	_expect_action_key("combo_w", KEY_W)
	_expect_action_key("combo_s", KEY_S)
	_expect_action_key("combo_space", KEY_SPACE)


func _check_phase1_files() -> void:
	_expect(FileAccess.file_exists("res://autoload/event_bus.gd"), "event_bus.gd should be migrated")
	_expect(FileAccess.file_exists("res://autoload/event_bus.gd.uid"), "event_bus.gd.uid should be migrated")
	_expect(FileAccess.file_exists("res://autoload/rhythm_manager.gd"), "rhythm_manager.gd should be migrated")
	_expect(FileAccess.file_exists("res://autoload/rhythm_manager.gd.uid"), "rhythm_manager.gd.uid should be migrated")
	_expect(FileAccess.file_exists("res://assets/audio/song.ogg"), "song.ogg should be migrated")
	_expect(FileAccess.file_exists("res://assets/audio/song.ogg.import"), "song.ogg.import should be migrated")


func _expect_action_unbound(action_name: StringName) -> void:
	_expect(InputMap.has_action(action_name), "%s action should exist" % action_name)
	if InputMap.has_action(action_name):
		_expect_int(InputMap.action_get_events(action_name).size(), 0, "%s should be registered but physically unbound" % action_name)


func _expect_action_key(action_name: StringName, keycode: Key) -> void:
	_expect(InputMap.has_action(action_name), "%s action should exist" % action_name)
	var found := false
	if InputMap.has_action(action_name):
		for event: InputEvent in InputMap.action_get_events(action_name):
			var key := event as InputEventKey
			if key != null and (key.physical_keycode == keycode or key.keycode == keycode):
				found = true
	_expect(found, "%s should bind %s" % [action_name, OS.get_keycode_string(keycode)])


func _file_contains(path: String, needle: String) -> bool:
	if not FileAccess.file_exists(path):
		return false
	var file := FileAccess.open(path, FileAccess.READ)
	if file == null:
		return false
	var text := file.get_as_text()
	file.close()
	return text.contains(needle)


func _expect(condition: bool, label: String) -> void:
	if not condition:
		failures.append(label)


func _expect_equal(actual, expected, label: String) -> void:
	if actual != expected:
		failures.append("%s: expected %s, got %s" % [label, str(expected), str(actual)])


func _expect_int(actual: int, expected: int, label: String) -> void:
	if actual != expected:
		failures.append("%s: expected %d, got %d" % [label, expected, actual])


func _finish() -> void:
	if failures.is_empty():
		print("PASS migration phase 0/1")
		quit(0)
	else:
		for failure: String in failures:
			push_error(failure)
		quit(1)