class_name copyMultiplayer
extends Mod_Base

@export var cache    := ""
@export var nickname := ""
@export var address  := ""
@export var port     := 52410

var main_controller: ModelController

## Hardcoded list of bone names that will get syncronized.
var tracked_bones: Array[String]

var version: int = -1
var bone_lookup: Array[String] = []
var blendshape_lookup: Array[NodePath] = []

# Temporary positioning system.
# TODO: Add a setting that allows syncing model positions, as an alternative
#       to letting the local player choose where each model is going to appear.
var player_order: Array[int] = []
var starting_offset     := Vector3(-1.25, 0.0, 0.0)
var accumulative_offset := Vector3( 0.35, 0.0, 0.0)

# FIXME: There is an edge case where you can load the settings while connected,
#        resulting in out-of-sync information with connected players, but so far
#        I don't believe this should be a source of issues.

func _ready() -> void:
	# FIXME: This is just thrown together. Dunno if this is an accurate list.
	# TODO: Allow specifying additional bones, with the help of a hierachical list of existing bones in the model.
	tracked_bones = [ "Hips", "Spine", "Chest", "UpperChest", "Neck", "Head" ]
	for side in [ "Left", "Right" ]:
		# Eyes
		tracked_bones.append("%sEye" % side)
		# Legs
		for bone in [ "UpperLeg", "LowerLeg", "Foot" ]:
			tracked_bones.append("%s%s" % [ side, bone ])
		# Arms
		for bone in [ "Shoulder", "UpperArm", "LowerArm", "Hand" ]:
			tracked_bones.append("%s%s" % [ side, bone ])
		# Fingers
		for phalange in [ "Metacarpal", "Proximal", "Distal" ]:
			tracked_bones.append("%sThumb%s" % [ side, phalange ])
		for finger in [ "Index", "Middle", "Ring", "Little" ]:
			for phalange in [ "Proximal", "Intermediate", "Distal" ]:
				tracked_bones.append("%s%s%s" % [ side, finger, phalange ])

	# FIXME: Hardcoded way to get the main model controller.
	main_controller = $"/root/SnekStudio_Main/ModelController"
	main_controller.child_entered_tree.connect(on_model_changed)
	on_model_changed(main_controller.get_node_or_null("Model"))

	setup_setting_widget("cache"   , "Cache/LineEdit", true )
	setup_setting_widget("nickname", "Name/LineEdit" , false)
	setup_setting_widget("address" , "Host/Address"  , true )
	setup_setting_widget("port"    , "Host/Port"     , true )
	setup_button_connections()

	# Filter whitespace characters from nickname before saving it to "nickname" field.
	var nickname_widget: LineEdit = get_settings_window().get_node("Name/LineEdit")
	nickname_widget.text_changed.connect(func(new_text): modify_setting("nickname", new_text.strip_edges()))
	nickname_widget.text_submitted.connect(func(_new_text): nickname_widget.text = nickname)
	nickname_widget.focus_exited.connect(func(): nickname_widget.text = nickname)

	multiplayer.peer_connected     .connect(on_peer_connected)
	multiplayer.peer_disconnected  .connect(on_peer_disconnected)
	multiplayer.connected_to_server.connect(on_connected_to_server)
	multiplayer.connection_failed  .connect(on_connection_failed)
	multiplayer.server_disconnected.connect(on_server_disconnected)

func _exit_tree() -> void:
	multiplayer.multiplayer_peer.close()

func _create_settings_window() -> Control:
	return load("res://Mods/copyMultiplayer/Resources/copy_multiplayer_settings.tscn").instantiate()

func setup_setting_widget(setting_name: String, path: NodePath, setup_events: bool) -> void:
	var settings = get_settings_window()
	var widget: Control = settings.get_node(path)

	_settings_properties.append({ name = setting_name, args = {  } })
	_settings_widgets_by_setting_name[setting_name] = widget

	if setup_events:
		if widget is LineEdit: widget.text_changed.connect(
			func(text): modify_setting(setting_name, text))
		if widget is SpinBox: widget.value_changed.connect(
			func(number): modify_setting(setting_name, roundi(number)))

func setup_button_connections() -> void:
	var window = get_settings_window()
	window.get_node("Buttons/Join").pressed.connect(on_join_pressed)
	window.get_node("Buttons/Host").pressed.connect(on_host_pressed)
	window.get_node("Buttons/Disconnect").pressed.connect(on_disconnect_pressed)


func on_join_pressed() -> void:
	var address_widget: LineEdit = get_settings_window().get_node("Host/Address")
	var default_address: String = address_widget.placeholder_text
	var actual_address := default_address if address.is_empty() else address

	var peer := ENetMultiplayerPeer.new()
	if peer.create_client(actual_address, port) == OK:
		multiplayer.multiplayer_peer = peer
		set_status("Connecting ...")
		print_log("Connecting to server")
		update_enabled_state(true)
	else:
		print_log("Unable to connect!")

func on_host_pressed() -> void:
	var peer := ENetMultiplayerPeer.new()
	if peer.create_server(port) == OK:
		multiplayer.multiplayer_peer = peer
		update_status()
		print_log("Opened server")
		update_enabled_state(true)
	else:
		print_log("Unable to open server!")

func on_disconnect_pressed() -> void:
	assert(multiplayer.multiplayer_peer)
	if multiplayer.is_server():
		set_status("")
		print_log("Closed server")
		update_enabled_state(false)
		clear_player_models()
	multiplayer.multiplayer_peer.close()


func on_peer_connected(id: int) -> void:
	var model_controller := ModelController.new()
	model_controller.name = str(id)
	var sync_controller := SyncController.new()
	sync_controller.name = "SyncController"
	model_controller.add_child(sync_controller)
	add_child(model_controller)

	player_order.append(id)
	update_model_transforms()

	# Send information to the newly connected player about ourselves.
	# (Technically this doesn't need to be relayed through the server, but oh well.)
	if nickname: change_nickname.rpc_id(id, nickname)
	var filename = main_controller._last_loaded_vrm.get_file()
	if filename.is_valid_filename(): change_model.rpc_id(id, version, bone_lookup, blendshape_lookup, filename)

	update_status()
	print_log("%s connected" % sync_controller.get_display_name())

func on_peer_disconnected(id: int) -> void:
	var controller = get_sync_controller(id)
	if not controller: return

	remove_child(controller.model_controller)
	controller.model_controller.queue_free()

	player_order.remove_at(player_order.find(id))
	update_model_transforms()

	update_status()
	print_log("Player %s disconnected" % id)

func on_connected_to_server() -> void:
	print_log("Connected to server")

func on_connection_failed() -> void:
	set_status("")
	print_log("Connection failed!")
	update_enabled_state(false)

func on_server_disconnected() -> void:
	set_status("")
	print_log("Disconnected from server")
	update_enabled_state(false)
	clear_player_models()


func update_enabled_state(is_online: bool) -> void:
	var window = get_settings_window()
	window.get_node("Name/LineEdit").editable = !is_online
	window.get_node("Host/Address" ).editable = !is_online
	window.get_node("Host/Port"    ).editable = !is_online
	window.get_node("Buttons/Join"      ).disabled =  is_online
	window.get_node("Buttons/Host"      ).disabled =  is_online
	window.get_node("Buttons/Disconnect").disabled = !is_online

func update_status() -> void:
	var num_players := 1 + multiplayer.get_peers().size()
	var side := "Hosting" if multiplayer.is_server() else "Connected"
	var s := "s" if num_players != 1 else ""
	set_status("%s: %d player%s" % [side, num_players, s])


# FIXME: Temporary hardcoded way to assign some offset to other players.
func update_model_transforms() -> void:
	var offset := starting_offset
	for id in player_order:
		var controller: ModelController = get_node(str(id))
		controller.position = offset
		offset += accumulative_offset
		update_model_rotation(controller)

## Rotates the model a little bit towards the camera
## so it doesn't appear to be staring into nowhere.
func update_model_rotation(controller: ModelController) -> void:
	var camera  := get_viewport().get_camera_3d()
	var from_2d := Vector2(controller.position.x, controller.position.z)
	var to_2d   := Vector2(camera.position.x, camera.position.z)
	controller.rotation.y = from_2d.angle_to_point(to_2d) / 4 # Magic value, probably depends on FOV.

## Removes all networked player models.
func clear_player_models() -> void:
	for controller in get_children():
		if controller is ModelController:
			remove_child(controller)
			controller.queue_free()
	player_order.clear()


func _process(_delta: float) -> void:
	SyncController.send_model_animation(self)

# Will be called once when the module is initialized, and also when a child is
# added to the main ModelController, which happens when the model is changed.
func on_model_changed(model: Node) -> void:
	if (model == null) or (model.name != "Model"): return

	var skeleton: Skeleton3D = main_controller._get_model_skeleton()
	if not skeleton: return # Do nothing, I guess? Unsure if potential bug.

	# This "version" is used to ensure that sync updates
	# are not applied to the incorrect lookup tables.
	version = (version + 1) % 256

	bone_lookup.clear()
	for bone_name in tracked_bones:
		var bone_idx := skeleton.find_bone(bone_name)
		if bone_idx == -1: continue
		bone_lookup.append(bone_name)

	blendshape_lookup.clear()
	var anim_player: AnimationPlayer = model.find_child("AnimationPlayer", false, false)
	for anim_name in anim_player.get_animation_list():
		if anim_name == "RESET": continue # Skip RESET animation?
		var anim := anim_player.get_animation(anim_name)
		for track_index in anim.get_track_count():
			if anim.track_get_type(track_index) == Animation.TYPE_BLEND_SHAPE:
				blendshape_lookup.append(anim.track_get_path(track_index))
				continue

	# Wait for one frame, then "_last_loaded_vrm" is updated.
	await get_tree().process_frame
	var filename = main_controller._last_loaded_vrm.get_file()

	change_model.rpc(version, bone_lookup, blendshape_lookup, filename)


## Gets the SyncController for the player with the specified peer id.
func get_sync_controller(peer_id: int) -> SyncController:
	var model_controller := get_node_or_null(str(peer_id)) as ModelController
	if not model_controller: return null
	return model_controller.get_node_or_null("SyncController") as SyncController

@rpc("any_peer", "reliable")
func change_nickname(new_nickname: String) -> void:
	var peer_id := multiplayer.get_remote_sender_id()
	var controller := get_sync_controller(peer_id)
	if controller: controller.change_nickname(new_nickname)

@rpc("any_peer", "reliable")
func change_model(
	new_version: int,
	new_bone_lookup: Array[String],
	new_blendshape_lookup: Array[NodePath],
	filename: String,
) -> void:
	var peer_id := multiplayer.get_remote_sender_id()
	var controller := get_sync_controller(peer_id)
	if controller: controller.change_model(new_version, new_bone_lookup, new_blendshape_lookup, filename)

@rpc("any_peer", "unreliable_ordered")
func sync_model_animation(
	current_version: int,
	uncompressed_length: int,
	buffer: PackedByteArray,
) -> void:
	var peer_id := multiplayer.get_remote_sender_id()
	var controller := get_sync_controller(peer_id)
	if controller: controller.sync_model_animation(current_version, uncompressed_length, buffer)