extends SceneTree

## Visual and structural gate for first-person movement handling.
##
## Run:
##   godot --path . --resolution 1280x720 \
##     --script res://debug/fp_movement_capture.gd -- <out_dir>

const DT := 1.0 / 60.0
const SETTLE_FRAMES := 42

var _out_dir := "."
var _frames := 0
var _booted := false
var _player: CharacterBody3D = null
var _machine: Node = null
var _manager: Node = null
var _case_index := 0
var _case_frame := 0
var _failures: Array[String] = []

# tag, state, velocity, wall side, crouching
var _cases := [
	["idle", "idle", Vector3.ZERO, 0.0, false],
	["jump", "air", Vector3(0.0, 9.0, -6.0), 0.0, false],
	["fall", "air", Vector3(0.0, -11.0, -7.0), 0.0, false],
	["dash", "dash", Vector3(0.0, 0.0, -18.0), 0.0, false],
	["slide", "slide", Vector3(0.0, 0.0, -13.0), 0.0, true],
	["wallrun_left", "wall_run", Vector3(0.0, 1.0, -11.0), -1.0, false],
	["wallrun_right", "wall_run", Vector3(0.0, 1.0, -11.0), 1.0, false],
	["wall_cling", "wall_cling", Vector3(0.0, 0.0, -2.0), -1.0, false],
	["grapple", "grapple", Vector3(4.0, 5.0, -15.0), 0.0, false],
]


func _initialize() -> void:
	var args := OS.get_cmdline_user_args()
	if not args.is_empty():
		_out_dir = args[0]
	if not _out_dir.is_absolute_path():
		_out_dir = ProjectSettings.globalize_path(_out_dir)
	var mkdir_error := DirAccess.make_dir_recursive_absolute(_out_dir)
	if mkdir_error != OK:
		printerr("FP_MOVEMENT could not create '%s' (error %d)" % [
			_out_dir, mkdir_error])
		quit(mkdir_error)
		return
	change_scene_to_file("res://ui/main_menu/main_menu.tscn")


func _process(_delta: float) -> bool:
	_frames += 1
	if not _booted and _frames == 40:
		_booted = true
		var network = root.get_node_or_null("NetworkManager")
		if network and network.has_method("start_singleplayer_match"):
			network.start_singleplayer_match(GameMode.DEATHMATCH)
		change_scene_to_file("res://scenes/maps/test_level/test_level.tscn")
		return false
	if _frames < 160:
		return false
	if _player == null:
		if not _setup():
			_finish()
			return true

	var entry: Array = _cases[_case_index]
	_machine.current_state = entry[1]
	_machine.wall_side = entry[3]
	_machine.input_crouch = entry[4]
	_player.velocity = entry[2]
	_manager._process(DT)
	_case_frame += 1
	if _case_frame >= SETTLE_FRAMES:
		_snap("fp_move_" + String(entry[0]))
		var pose: Dictionary = _manager.movement_pose_debug()
		var position: Vector3 = pose.get("position", Vector3.ZERO)
		var rotation: Vector3 = pose.get("rotation", Vector3.ZERO)
		if entry[0] != "idle" and position.length() < 0.012 \
				and rotation.length() < 0.025:
			_failures.append("%s did not produce a readable movement pose" % entry[0])
		print("FP_MOVEMENT pose %s position=%s rotation_deg=%s" % [
			entry[0], position, rotation * (180.0 / PI)])
		_case_index += 1
		_case_frame = 0
		if _case_index >= _cases.size():
			_finish()
			return true
	return false


func _setup() -> bool:
	for candidate in root.find_children("*", "CharacterBody3D", true, false):
		if candidate.has_method("get_visual_model") \
				and candidate.is_multiplayer_authority():
			_player = candidate
			break
	if _player == null:
		_failures.append("local player was not created")
		return false
	_machine = _player.get_node_or_null("MovementStateMachine")
	_manager = _player.get_node_or_null("HeadPivot/Camera3D/WeaponManager")
	if _machine == null:
		_failures.append("MovementStateMachine is missing")
	if _manager == null:
		_failures.append("WeaponManager is missing")
	if not _failures.is_empty():
		return false
	_player.set_physics_process(false)
	_machine.set_physics_process(false)
	_manager.set_process(false)
	_player.global_position = Vector3(0.0, 1.2, 14.0)

	var obsolete := root.find_children(
		"FirstPersonBody", "Node", true, false)
	if not obsolete.is_empty():
		_failures.append("obsolete first-person body/legs still exist")
	if _manager.weapons.is_empty():
		_failures.append("viewmodel weapon loadout is empty")
	return _failures.is_empty()


func _snap(tag: String) -> void:
	var image := root.get_viewport().get_texture().get_image()
	var path := _out_dir.path_join(tag + ".png")
	var error := image.save_png(path)
	if error == OK:
		print("FP_MOVEMENT saved ", path)
	else:
		_failures.append("could not save %s (error %d)" % [path, error])


func _finish() -> void:
	if _failures.is_empty() and _case_index >= _cases.size():
		print("FP_MOVEMENT PASS: %d authored poses, no first-person legs" \
			% _cases.size())
		quit(0)
	else:
		for failure in _failures:
			push_error("FP_MOVEMENT FAIL: " + failure)
		quit(1)