Code stuff

addons/imjp94.yafsm/scenes/ContextMenu.tscn

@@ -0,0 +1,12 @@
+[gd_scene format=3 uid="uid://cflltb00e10be"]
+
+[node name="ContextMenu" type="PopupMenu"]
+size = Vector2i(104, 100)
+visible = true
+item_count = 3
+item_0/text = "Add State"
+item_0/id = 0
+item_1/text = "Add Entry"
+item_1/id = 1
+item_2/text = "Add Exit"
+item_2/id = 2

addons/imjp94.yafsm/scenes/ParametersPanel.gd

@@ -0,0 +1,63 @@
+@tool
+extends MarginContainer
+
+
+@onready var grid = $PanelContainer/MarginContainer/VBoxContainer/GridContainer
+@onready var button = $PanelContainer/MarginContainer/VBoxContainer/MarginContainer/Button
+
+
+func _ready():
+	button.pressed.connect(_on_button_pressed)
+
+func update_params(params, local_params):
+	# Remove erased parameters from param panel
+	for param in grid.get_children():
+		if not (param.name in params):
+			remove_param(param.name)
+	for param in params:
+		var value = params[param]
+		if value == null: # Ignore trigger
+			continue
+		set_param(param, str(value))
+
+	# Remove erased local parameters from param panel
+	for param in grid.get_children():
+		if not (param.name in local_params) and not (param.name in params):
+			remove_param(param.name)
+	for param in local_params:
+		var nested_params = local_params[param]
+		for nested_param in nested_params:
+			var value = nested_params[nested_param]
+			if value == null: # Ignore trigger
+				continue
+			set_param(str(param, "/", nested_param), str(value))
+
+func set_param(param, value):
+	var label = grid.get_node_or_null(NodePath(param))
+	if not label:
+		label = Label.new()
+		label.name = param
+		grid.add_child(label)
+
+	label.text = "%s = %s" % [param, value]
+
+func remove_param(param):
+	var label = grid.get_node_or_null(NodePath(param))
+	if label:
+		grid.remove_child(label)
+		label.queue_free()
+		set_anchors_preset(PRESET_BOTTOM_RIGHT)
+
+func clear_params():
+	for child in grid.get_children():
+		grid.remove_child(child)
+		child.queue_free()
+
+func _on_button_pressed():
+	grid.visible = !grid.visible
+	if grid.visible:
+		button.text = "Hide params"
+	else:
+		button.text = "Show params"
+	
+	set_anchors_preset(PRESET_BOTTOM_RIGHT)

addons/imjp94.yafsm/scenes/PathViewer.gd

@@ -0,0 +1,64 @@
+@tool
+extends HBoxContainer
+
+signal dir_pressed(dir, index)
+
+
+func _init():
+	add_dir("root")
+
+# Select parent dir & return its path
+func back():
+	return select_dir(get_child(max(get_child_count()-1 - 1, 0)).name)
+
+# Select dir & return its path
+func select_dir(dir):
+	for i in get_child_count():
+		var child = get_child(i)
+		if child.name == dir:
+			remove_dir_until(i)
+			return get_dir_until(i)
+
+# Add directory button
+func add_dir(dir):
+	var button = Button.new()
+	button.name = dir
+	button.flat = true
+	button.text = dir
+	add_child(button)
+	button.pressed.connect(_on_button_pressed.bind(button))
+	return button
+
+# Remove directory until index(exclusive)
+func remove_dir_until(index):
+	var to_remove = []
+	for i in get_child_count():
+		if index == get_child_count()-1 - i:
+			break
+		var child = get_child(get_child_count()-1 - i)
+		to_remove.append(child)
+	for n in to_remove:
+		remove_child(n)
+		n.queue_free()
+
+# Return current working directory
+func get_cwd():
+	return get_dir_until(get_child_count()-1)
+
+# Return path until index(inclusive) of directory
+func get_dir_until(index):
+	var path = ""
+	for i in get_child_count():
+		if i > index:
+			break
+		var child = get_child(i)
+		if i == 0:
+			path = "root"
+		else:
+			path = str(path, "/", child.text)
+	return path
+
+func _on_button_pressed(button):
+	var index = button.get_index()
+	var dir = button.name
+	emit_signal("dir_pressed", dir, index)

addons/imjp94.yafsm/scenes/StateMachineEditor.gd

@@ -0,0 +1,761 @@
+@tool
+extends "res://addons/imjp94.yafsm/scenes/flowchart/FlowChart.gd"
+
+const StateMachine = preload("../src/states/StateMachine.gd")
+const Transition = preload("../src/transitions/Transition.gd")
+const State = preload("../src/states/State.gd")
+const StateDirectory = preload("../src/StateDirectory.gd")
+const StateNode = preload("state_nodes/StateNode.tscn")
+const TransitionLine = preload("transition_editors/TransitionLine.tscn")
+const StateNodeScript = preload("state_nodes/StateNode.gd")
+const StateMachineEditorLayer = preload("StateMachineEditorLayer.gd")
+const PathViewer = preload("PathViewer.gd")
+
+signal inspector_changed(property) # Inform plugin to refresh inspector
+signal debug_mode_changed(new_debug_mode)
+
+const ENTRY_STATE_MISSING_MSG = {
+	"key": "entry_state_missing",
+	"text": "Entry State missing, it will never get started. Right-click -> \"Add Entry\"."
+}
+const EXIT_STATE_MISSING_MSG = {
+	"key": "exit_state_missing",
+	"text": "Exit State missing, it will never exit from nested state. Right-click -> \"Add Exit\"."
+}
+const DEBUG_MODE_MSG = {
+	"key": "debug_mode",
+	"text": "Debug Mode"
+}
+
+@onready var context_menu = $ContextMenu
+@onready var state_node_context_menu = $StateNodeContextMenu
+@onready var convert_to_state_confirmation = $ConvertToStateConfirmation
+@onready var save_dialog = $SaveDialog
+@onready var create_new_state_machine_container = $MarginContainer
+@onready var create_new_state_machine = $MarginContainer/CreateNewStateMachine
+@onready var param_panel = $ParametersPanel
+var path_viewer = HBoxContainer.new()
+var condition_visibility = TextureButton.new()
+var unsaved_indicator = Label.new()
+var message_box = VBoxContainer.new()
+
+var editor_accent_color = Color.WHITE
+var transition_arrow_icon
+
+var undo_redo: EditorUndoRedoManager
+
+var debug_mode: = false:
+	set = set_debug_mode
+var state_machine_player:
+	set = set_state_machine_player
+var state_machine:
+	set = set_state_machine
+var can_gui_name_edit = true
+var can_gui_context_menu = true
+
+var _reconnecting_connection
+var _last_index = 0
+var _last_path = ""
+var _message_box_dict = {}
+var _context_node
+var _current_state = ""
+var _last_stack = []
+
+
+func _init():
+	super._init()
+	
+	path_viewer.mouse_filter = MOUSE_FILTER_IGNORE
+	path_viewer.set_script(PathViewer)
+	path_viewer.dir_pressed.connect(_on_path_viewer_dir_pressed)
+	top_bar.add_child(path_viewer)
+
+	condition_visibility.tooltip_text = "Hide/Show Conditions on Transition Line"
+	condition_visibility.stretch_mode = TextureButton.STRETCH_KEEP_ASPECT_CENTERED
+	condition_visibility.toggle_mode = true
+	condition_visibility.size_flags_vertical = SIZE_SHRINK_CENTER
+	condition_visibility.focus_mode = FOCUS_NONE
+	condition_visibility.pressed.connect(_on_condition_visibility_pressed)
+	condition_visibility.button_pressed = true
+	gadget.add_child(condition_visibility)
+
+	unsaved_indicator.size_flags_vertical = SIZE_SHRINK_CENTER
+	unsaved_indicator.focus_mode = FOCUS_NONE
+	gadget.add_child(unsaved_indicator)
+
+	message_box.set_anchors_and_offsets_preset(PRESET_BOTTOM_WIDE)
+	message_box.grow_vertical = GROW_DIRECTION_BEGIN
+	add_child(message_box)
+
+	content.get_child(0).name = "root"
+
+	set_process(false)
+
+func _ready():
+	create_new_state_machine_container.visible = false
+	create_new_state_machine.pressed.connect(_on_create_new_state_machine_pressed)
+	context_menu.index_pressed.connect(_on_context_menu_index_pressed)
+	state_node_context_menu.index_pressed.connect(_on_state_node_context_menu_index_pressed)
+	convert_to_state_confirmation.confirmed.connect(_on_convert_to_state_confirmation_confirmed)
+	save_dialog.confirmed.connect(_on_save_dialog_confirmed)
+
+func _process(delta):
+	if not debug_mode:
+		set_process(false)
+		return
+	if not is_instance_valid(state_machine_player):
+		set_process(false)
+		set_debug_mode(false)
+		return
+	var stack = state_machine_player.get("Members/StackPlayer.gd/stack")
+	if ((stack == []) or (stack==null)):
+		set_process(false)
+		set_debug_mode(false)
+		return
+
+	if stack.size() == 1:
+		set_current_state(state_machine_player.get("Members/StackPlayer.gd/current"))
+	else:
+		var stack_max_index = stack.size() - 1
+		var prev_index = stack.find(_current_state)
+		if prev_index == -1:
+			if _last_stack.size() < stack.size():
+				# Reproduce transition, for example:
+				# [Entry, Idle, Walk]
+				# [Entry, Idle, Jump, Fall]
+				# Walk -> Idle
+				# Idle -> Jump
+				# Jump -> Fall
+				var common_index = -1
+				for i in _last_stack.size():
+					if _last_stack[i] == stack[i]:
+						common_index = i
+						break
+				if common_index > -1:
+					var count_from_last_stack = _last_stack.size()-1 - common_index -1
+					_last_stack.reverse()
+					# Transit back to common state
+					for i in count_from_last_stack:
+						set_current_state(_last_stack[i + 1])
+					# Transit to all missing state in current stack
+					for i in range(common_index + 1, stack.size()):
+						set_current_state(stack[i])
+				else:
+					set_current_state(stack.back())
+			else:
+				set_current_state(stack.back())
+		else:
+			# Set every skipped state
+			var missing_count = stack_max_index - prev_index
+			for i in range(1, missing_count + 1):
+				set_current_state(stack[prev_index + i])
+	_last_stack = stack
+	var params = state_machine_player.get("Members/_parameters")
+	var local_params = state_machine_player.get("Members/_local_parameters")
+	if params == null:
+		params = state_machine_player.get("Members/StateMachinePlayer.gd/_parameters")
+		local_params = state_machine_player.get("Members/StateMachinePlayer.gd/_local_parameters")
+	param_panel.update_params(params, local_params)
+	get_focused_layer(_current_state).debug_update(_current_state, params, local_params)
+
+func _on_path_viewer_dir_pressed(dir, index):
+	var path = path_viewer.select_dir(dir)
+	select_layer(get_layer(path))
+
+	if _last_index > index:
+		# Going backward
+		var end_state_parent_path = StateMachinePlayer.path_backward(_last_path)
+		var end_state_name = StateMachinePlayer.path_end_dir(_last_path)
+		var layer = content.get_node_or_null(NodePath(end_state_parent_path))
+		if layer:
+			var node = layer.content_nodes.get_node_or_null(NodePath(end_state_name))
+			if node:
+				var cond_1 = (not ("states" in node.state)) or (node.state.states=={})  # states property not defined or empty
+				# Now check if, for some reason, there are an Entry and/or an Exit node inside this node
+				# not registered in the states variable above.
+				var nested_layer = content.get_node_or_null(NodePath(_last_path))
+				var cond_2 = (nested_layer.content_nodes.get_node_or_null(NodePath(State.ENTRY_STATE)) == null)  # there is no entry state in the node
+				var cond_3 = (nested_layer.content_nodes.get_node_or_null(NodePath(State.EXIT_STATE)) == null)  # there is no exit state in the node
+				if (cond_1 and cond_2 and cond_3):
+					# Convert state machine node back to state node
+					convert_to_state(layer, node)
+
+	_last_index = index
+	_last_path = path
+
+func _on_context_menu_index_pressed(index):
+	var new_node = StateNode.instantiate()
+	new_node.theme.get_stylebox("focus", "FlowChartNode").border_color = editor_accent_color
+	match index:
+		0: # Add State
+			## Handle state name duplication (4.x changed how duplicates are
+			## automatically handled and gave a random index instead of
+			## a progressive one)
+			var default_new_state_name = "State"
+			var state_dup_index = 0
+			var new_name = default_new_state_name
+			for state_name in current_layer.state_machine.states:
+				if (state_name == new_name):
+					state_dup_index += 1
+					new_name = "%s%s" % [default_new_state_name, state_dup_index]
+			new_node.name = new_name
+		1: # Add Entry
+			if State.ENTRY_STATE in current_layer.state_machine.states:
+				push_warning("Entry node already exist")
+				return
+			new_node.name = State.ENTRY_STATE
+		2: # Add Exit
+			if State.EXIT_STATE in current_layer.state_machine.states:
+				push_warning("Exit node already exist")
+				return
+			new_node.name = State.EXIT_STATE
+	new_node.position = content_position(get_local_mouse_position())
+	add_node(current_layer, new_node)
+
+func _on_state_node_context_menu_index_pressed(index):
+	if not _context_node:
+		return
+
+	match index:
+		0: # Copy
+			_copying_nodes = [_context_node]
+			_context_node = null
+		1: # Duplicate
+			duplicate_nodes(current_layer, [_context_node])
+			_context_node = null
+		2: # Delete
+			remove_node(current_layer, _context_node.name)
+			for connection_pair in current_layer.get_connection_list():
+				if connection_pair.from == _context_node.name or connection_pair.to == _context_node.name:
+					disconnect_node(current_layer, connection_pair.from, connection_pair.to).queue_free()
+			_context_node = null
+		3: # Separator
+			_context_node = null
+		4: # Convert
+			convert_to_state_confirmation.popup_centered()
+
+func _on_convert_to_state_confirmation_confirmed():
+	convert_to_state(current_layer, _context_node)
+	_context_node.queue_redraw() # Update outlook of node
+	# Remove layer
+	var path = str(path_viewer.get_cwd(), "/", _context_node.name)
+	var layer = get_layer(path)
+	if layer:
+		layer.queue_free()
+	_context_node = null
+
+func _on_save_dialog_confirmed():
+	save()
+
+func _on_create_new_state_machine_pressed():
+	var new_state_machine = StateMachine.new()
+	
+	undo_redo.create_action("Create New StateMachine")
+	
+	undo_redo.add_do_reference(new_state_machine)
+	undo_redo.add_do_property(state_machine_player, "state_machine", new_state_machine)
+	undo_redo.add_do_method(self, "set_state_machine", new_state_machine)
+	undo_redo.add_do_property(create_new_state_machine_container, "visible", false)
+	undo_redo.add_do_method(self, "check_has_entry")
+	undo_redo.add_do_method(self, "emit_signal", "inspector_changed", "state_machine")
+	
+	undo_redo.add_undo_property(state_machine_player, "state_machine", null)
+	undo_redo.add_undo_method(self, "set_state_machine", null)
+	undo_redo.add_undo_property(create_new_state_machine_container, "visible", true)
+	undo_redo.add_undo_method(self, "check_has_entry")
+	undo_redo.add_undo_method(self, "emit_signal", "inspector_changed", "state_machine")
+	
+	undo_redo.commit_action()
+
+func _on_condition_visibility_pressed():
+	for line in current_layer.content_lines.get_children():
+		line.vbox.visible = condition_visibility.button_pressed
+
+func _on_debug_mode_changed(new_debug_mode):
+	if new_debug_mode:
+		param_panel.show()
+		add_message(DEBUG_MODE_MSG.key, DEBUG_MODE_MSG.text)
+		set_process(true)
+		# mouse_filter = MOUSE_FILTER_IGNORE
+		can_gui_select_node = false
+		can_gui_delete_node = false
+		can_gui_connect_node = false
+		can_gui_name_edit = false
+		can_gui_context_menu = false
+	else:
+		param_panel.clear_params()
+		param_panel.hide()
+		remove_message(DEBUG_MODE_MSG.key)
+		set_process(false)
+		can_gui_select_node = true
+		can_gui_delete_node = true
+		can_gui_connect_node = true
+		can_gui_name_edit = true
+		can_gui_context_menu = true
+
+func _on_state_machine_player_changed(new_state_machine_player):
+	if not state_machine_player:
+		return
+	if new_state_machine_player.get_class() == "EditorDebuggerRemoteObject":
+		return
+
+	if new_state_machine_player:
+		create_new_state_machine_container.visible = !new_state_machine_player.state_machine
+	else:
+		create_new_state_machine_container.visible = false
+
+func _on_state_machine_changed(new_state_machine):
+	var root_layer = get_layer("root")
+	path_viewer.select_dir("root") # Before select_layer, so path_viewer will be updated in _on_layer_selected
+	select_layer(root_layer)
+	clear_graph(root_layer)
+	# Reset layers & path viewer
+	for child in root_layer.get_children():
+		if child is FlowChartLayer:
+			root_layer.remove_child(child)
+			child.queue_free()
+	if new_state_machine:
+		root_layer.state_machine = state_machine
+		var validated = StateMachine.validate(new_state_machine)
+		if validated:
+			print_debug("gd-YAFSM: Corrupted StateMachine Resource fixed, save to apply the fix.")
+		draw_graph(root_layer)
+		check_has_entry()
+
+func _gui_input(event):
+	super._gui_input(event)
+	
+	if event is InputEventMouseButton:
+		match event.button_index:
+			MOUSE_BUTTON_RIGHT:
+				if event.pressed and can_gui_context_menu:
+					context_menu.set_item_disabled(1, current_layer.state_machine.has_entry())
+					context_menu.set_item_disabled(2, current_layer.state_machine.has_exit())
+					context_menu.position = get_window().position + Vector2i(get_viewport().get_mouse_position())
+					context_menu.popup()
+
+func _input(event):
+	# Intercept save action
+	if visible:
+		if event is InputEventKey:
+			match event.keycode:
+				KEY_S:
+					if event.ctrl_pressed and event.pressed:
+						save_request()
+
+func create_layer(node):
+	# Create/Move to new layer
+	var new_state_machine = convert_to_state_machine(current_layer, node)
+	# Determine current layer path
+	var parent_path = path_viewer.get_cwd()
+	var path = str(parent_path, "/", node.name)
+	var layer = get_layer(path)
+	path_viewer.add_dir(node.state.name) # Before select_layer, so path_viewer will be updated in _on_layer_selected
+	if not layer:
+		# New layer to spawn
+		layer = add_layer_to(get_layer(parent_path))
+		layer.name = node.state.name
+		layer.state_machine = new_state_machine
+		draw_graph(layer)
+	_last_index = path_viewer.get_child_count()-1
+	_last_path = path
+	return layer
+
+func open_layer(path):
+	var dir = StateDirectory.new(path)
+	dir.goto(dir.get_end_index())
+	dir.back()
+	var next_layer = get_next_layer(dir, get_layer("root"))
+	select_layer(next_layer)
+	return next_layer
+
+# Recursively get next layer
+func get_next_layer(dir, base_layer):
+	var next_layer = base_layer
+	var np = dir.next()
+	if np:
+		next_layer = base_layer.get_node_or_null(NodePath(np))
+		if next_layer:
+			next_layer = get_next_layer(dir, next_layer)
+		else:
+			var to_dir = StateDirectory.new(dir.get_current())
+			to_dir.goto(to_dir.get_end_index())
+			to_dir.back()
+			var node = base_layer.content_nodes.get_node_or_null(NodePath(to_dir.get_current_end()))
+			next_layer = get_next_layer(dir, create_layer(node))
+	return next_layer
+
+func get_focused_layer(state):
+	var current_dir = StateDirectory.new(state)
+	current_dir.goto(current_dir.get_end_index())
+	current_dir.back()
+	return get_layer(str("root/", current_dir.get_current()))
+
+func _on_state_node_gui_input(event, node):
+	if node.state.is_entry() or node.state.is_exit():
+		return
+
+	if event is InputEventMouseButton:
+		match event.button_index:
+			MOUSE_BUTTON_LEFT:
+				if event.pressed:
+					if event.double_click:
+						if node.name_edit.get_rect().has_point(event.position) and can_gui_name_edit:
+							# Edit State name if within LineEdit
+							node.enable_name_edit(true)
+							accept_event()
+						else:
+							var layer = create_layer(node)
+							select_layer(layer)
+							accept_event()
+			MOUSE_BUTTON_RIGHT:
+				if event.pressed:
+					# State node context menu
+					_context_node = node
+					state_node_context_menu.position = get_window().position + Vector2i(get_viewport().get_mouse_position())
+					state_node_context_menu.popup()
+					state_node_context_menu.set_item_disabled(4, not (node.state is StateMachine))
+					accept_event()
+
+func convert_to_state_machine(layer, node):
+	# Convert State to StateMachine
+	var new_state_machine
+	if node.state is StateMachine:
+		new_state_machine = node.state
+	else:
+		new_state_machine = StateMachine.new()
+		new_state_machine.name = node.state.name
+		new_state_machine.graph_offset = node.state.graph_offset
+		layer.state_machine.remove_state(node.state.name)
+		layer.state_machine.add_state(new_state_machine)
+		node.state = new_state_machine
+	return new_state_machine
+
+func convert_to_state(layer, node):
+	# Convert StateMachine to State
+	var new_state
+	if node.state is StateMachine:
+		new_state = State.new()
+		new_state.name = node.state.name
+		new_state.graph_offset = node.state.graph_offset
+		layer.state_machine.remove_state(node.state.name)
+		layer.state_machine.add_state(new_state)
+		node.state = new_state
+	else:
+		new_state = node.state
+	return new_state
+
+func create_layer_instance():
+	var layer = Control.new()
+	layer.set_script(StateMachineEditorLayer)
+	layer.editor_accent_color = editor_accent_color
+	return layer
+
+func create_line_instance():
+	var line = TransitionLine.instantiate()
+	line.theme.get_stylebox("focus", "FlowChartLine").shadow_color = editor_accent_color
+	line.theme.set_icon("arrow", "FlowChartLine", transition_arrow_icon)
+	return line
+
+# Request to save current editing StateMachine
+func save_request():
+	if not can_save():
+		return
+
+	save_dialog.dialog_text = "Saving StateMachine to %s" % state_machine.resource_path
+	save_dialog.popup_centered()
+
+# Save current editing StateMachine
+func save():
+	if not can_save():
+		return
+	
+	unsaved_indicator.text = ""
+	ResourceSaver.save(state_machine, state_machine.resource_path)
+
+# Clear editor
+func clear_graph(layer):
+	clear_connections()
+	
+	for child in layer.content_nodes.get_children():
+		if child is StateNodeScript:
+			layer.content_nodes.remove_child(child)
+			child.queue_free()
+	
+	queue_redraw()
+	unsaved_indicator.text = "" # Clear graph is not action by user
+
+# Intialize editor with current editing StateMachine
+func draw_graph(layer):
+	for state_key in layer.state_machine.states.keys():
+		var state = layer.state_machine.states[state_key]
+		var new_node = StateNode.instantiate()
+		new_node.theme.get_stylebox("focus", "FlowChartNode").border_color = editor_accent_color
+		new_node.name = state_key # Set before add_node to let engine handle duplicate name
+		add_node(layer, new_node)
+		# Set after add_node to make sure UIs are initialized
+		new_node.state = state
+		new_node.state.name = state_key
+		new_node.position = state.graph_offset
+	for state_key in layer.state_machine.states.keys():
+		var from_transitions = layer.state_machine.transitions.get(state_key)
+		if from_transitions:
+			for transition in from_transitions.values():
+				connect_node(layer, transition.from, transition.to)
+				layer._connections[transition.from][transition.to].line.transition = transition
+	queue_redraw()
+	unsaved_indicator.text = "" # Draw graph is not action by user
+
+# Add message to message_box(overlay text at bottom of editor)
+func add_message(key, text):
+	var label = Label.new()
+	label.text = text
+	_message_box_dict[key] = label
+	message_box.add_child(label)
+	return label
+
+# Remove message from message_box
+func remove_message(key):
+	var control = _message_box_dict.get(key)
+	if control:
+		_message_box_dict.erase(key)
+		message_box.remove_child(control)
+		# Weird behavior of VBoxContainer, only sort children properly after changing grow_direction
+		message_box.grow_vertical = GROW_DIRECTION_END
+		message_box.grow_vertical = GROW_DIRECTION_BEGIN
+		return true
+	return false
+
+# Check if current editing StateMachine has entry, warns user if entry state missing
+func check_has_entry():
+	if not current_layer.state_machine:
+		return
+	if not current_layer.state_machine.has_entry():
+		if not (ENTRY_STATE_MISSING_MSG.key in _message_box_dict):
+			add_message(ENTRY_STATE_MISSING_MSG.key, ENTRY_STATE_MISSING_MSG.text)
+	else:
+		if ENTRY_STATE_MISSING_MSG.key in  _message_box_dict:
+			remove_message(ENTRY_STATE_MISSING_MSG.key)
+
+# Check if current editing StateMachine is nested and has exit, warns user if exit state missing
+func check_has_exit():
+	if not current_layer.state_machine:
+		return
+	if not path_viewer.get_cwd() == "root": # Nested state
+		if not current_layer.state_machine.has_exit():
+			if not (EXIT_STATE_MISSING_MSG.key in _message_box_dict):
+				add_message(EXIT_STATE_MISSING_MSG.key, EXIT_STATE_MISSING_MSG.text)
+			return
+	if EXIT_STATE_MISSING_MSG.key in _message_box_dict:
+		remove_message(EXIT_STATE_MISSING_MSG.key)
+
+func _on_layer_selected(layer):
+	if layer:
+		layer.show_content()
+		check_has_entry()
+		check_has_exit()
+
+func _on_layer_deselected(layer):
+	if layer:
+		layer.hide_content()
+
+func _on_node_dragged(layer, node, dragged):
+	node.state.graph_offset = node.position
+	_on_edited()
+
+func _on_node_added(layer, new_node):
+	# Godot 4 duplicates node with an internal @ name, which breaks everything
+	while String(new_node.name).begins_with("@"):
+		new_node.name = String(new_node.name).lstrip("@")
+	
+	new_node.undo_redo = undo_redo
+	new_node.state.name = new_node.name
+	new_node.state.graph_offset = new_node.position
+	new_node.name_edit_entered.connect(_on_node_name_edit_entered.bind(new_node))
+	new_node.gui_input.connect(_on_state_node_gui_input.bind(new_node))
+	layer.state_machine.add_state(new_node.state)
+	check_has_entry()
+	check_has_exit()
+	_on_edited()
+
+func _on_node_removed(layer, node_name):
+	var path = str(path_viewer.get_cwd(), "/", node_name)
+	var layer_to_remove = get_layer(path)
+	if layer_to_remove:
+		layer_to_remove.get_parent().remove_child(layer_to_remove)
+		layer_to_remove.queue_free()
+	var result = layer.state_machine.remove_state(node_name)
+	check_has_entry()
+	check_has_exit()
+	_on_edited()
+	return result
+
+func _on_node_connected(layer, from, to):
+	if _reconnecting_connection:
+		# Reconnection will trigger _on_node_connected after _on_node_reconnect_end/_on_node_reconnect_failed
+		if is_instance_valid(_reconnecting_connection.from_node) and \
+		_reconnecting_connection.from_node.name == from and \
+		is_instance_valid(_reconnecting_connection.to_node) and \
+		_reconnecting_connection.to_node.name == to:
+			_reconnecting_connection = null
+			return
+	if layer.state_machine.transitions.has(from):
+		if layer.state_machine.transitions[from].has(to):
+			return # Already existed as it is loaded from file
+
+	var line = layer._connections[from][to].line
+	var new_transition = Transition.new(from, to)
+	line.transition = new_transition
+	layer.state_machine.add_transition(new_transition)
+	clear_selection()
+	select(line)
+	_on_edited()
+
+func _on_node_disconnected(layer, from, to):
+	layer.state_machine.remove_transition(from, to)
+	_on_edited()
+
+func _on_node_reconnect_begin(layer, from, to):
+	_reconnecting_connection = layer._connections[from][to]
+	layer.state_machine.remove_transition(from, to)
+
+func _on_node_reconnect_end(layer, from, to):
+	var transition = _reconnecting_connection.line.transition
+	transition.to = to
+	layer.state_machine.add_transition(transition)
+	clear_selection()
+	select(_reconnecting_connection.line)
+
+func _on_node_reconnect_failed(layer, from, to):
+	var transition = _reconnecting_connection.line.transition
+	layer.state_machine.add_transition(transition)
+	clear_selection()
+	select(_reconnecting_connection.line)
+
+func _request_connect_from(layer, from):
+	if from == State.EXIT_STATE:
+		return false
+	return true
+
+func _request_connect_to(layer, to):
+	if to == State.ENTRY_STATE:
+		return false
+	return true
+
+func _on_duplicated(layer, old_nodes, new_nodes):
+	# Duplicate condition as well
+	for i in old_nodes.size():
+		var from_node = old_nodes[i]
+		for connection_pair in get_connection_list():
+			if from_node.name == connection_pair.from:
+				for j in old_nodes.size():
+					var to_node = old_nodes[j]
+					if to_node.name == connection_pair.to:
+						var old_connection = layer._connections[connection_pair.from][connection_pair.to]
+						var new_connection = layer._connections[new_nodes[i].name][new_nodes[j].name]
+						for condition in old_connection.line.transition.conditions.values():
+							new_connection.line.transition.add_condition(condition.duplicate())
+	_on_edited()
+
+func _on_node_name_edit_entered(new_name, node):
+	var old = node.state.name
+	var new = new_name
+	if old == new:
+		return
+	if "/" in new or "\\" in new: # No back/forward-slash
+		push_warning("Illegal State Name: / and \\ are not allowed in State name(%s)" % new)
+		node.name_edit.text = old
+		return
+
+	if current_layer.state_machine.change_state_name(old, new):
+		rename_node(current_layer, node.name, new)
+		node.name = new
+		# Rename layer as well
+		var path = str(path_viewer.get_cwd(), "/", node.name)
+		var layer = get_layer(path)
+		if layer:
+			layer.name = new
+		for child in path_viewer.get_children():
+			if child.text == old:
+				child.text = new
+				break
+		_on_edited()
+	else:
+		node.name_edit.text = old
+
+func _on_edited():
+	unsaved_indicator.text = "*"
+
+func _on_remote_transited(from, to):
+	var from_dir = StateDirectory.new(from)
+	var to_dir = StateDirectory.new(to)
+	var focused_layer = get_focused_layer(from)
+	if from:
+		if focused_layer:
+			focused_layer.debug_transit_out(from, to)
+	if to:
+		if from_dir.is_nested() and from_dir.is_exit():
+			if focused_layer:
+				var path = path_viewer.back()
+				select_layer(get_layer(path))
+		elif to_dir.is_nested():
+			if to_dir.is_entry() and focused_layer:
+			# Open into next layer
+				to_dir.goto(to_dir.get_end_index())
+				to_dir.back()
+				var node = focused_layer.content_nodes.get_node_or_null(NodePath(to_dir.get_current_end()))
+				if node:
+					var layer = create_layer(node)
+					select_layer(layer)
+		# In case where, "from" state is nested yet not an exit state,
+		# while "to" state is on different level, then jump to destination layer directly.
+		# This happens when StateMachinePlayer transit to state that existing in the stack,
+		# which trigger StackPlayer.reset() and cause multiple states removed from stack within one frame
+		elif from_dir.is_nested() and not from_dir.is_exit():
+			if to_dir._dirs.size() != from_dir._dirs.size():
+				to_dir.goto(to_dir.get_end_index())
+				var n = to_dir.back()
+				if not n:
+					n = "root"
+				var layer = get_layer(n)
+				path_viewer.select_dir(layer.name)
+				select_layer(layer)
+
+		focused_layer = get_focused_layer(to)
+		if not focused_layer:
+			focused_layer = open_layer(to)
+		focused_layer.debug_transit_in(from, to)
+
+# Return if current editing StateMachine can be saved, ignore built-in resource
+func can_save():
+	if not state_machine:
+		return false
+	var resource_path = state_machine.resource_path
+	if resource_path.is_empty():
+		return false
+	if ".scn" in resource_path or ".tscn" in resource_path: # Built-in resource will be saved by scene
+		return false
+	return true
+
+func set_debug_mode(v):
+	if debug_mode != v:
+		debug_mode = v
+		_on_debug_mode_changed(v)
+		emit_signal("debug_mode_changed", debug_mode)
+
+func set_state_machine_player(smp):
+	if state_machine_player != smp:
+		state_machine_player = smp
+		_on_state_machine_player_changed(smp)
+
+func set_state_machine(sm):
+	if state_machine != sm:
+		state_machine = sm
+		_on_state_machine_changed(sm)
+
+func set_current_state(v):
+	if _current_state != v:
+		var from = _current_state
+		var to = v
+		_current_state = v
+		_on_remote_transited(from, to)

addons/imjp94.yafsm/scenes/StateMachineEditor.tscn

@@ -0,0 +1,101 @@
+[gd_scene load_steps=5 format=3 uid="uid://bp2f3rs2sgn8g"]
+
+[ext_resource type="PackedScene" uid="uid://ccv81pntbud75" path="res://addons/imjp94.yafsm/scenes/StateNodeContextMenu.tscn" id="1"]
+[ext_resource type="Script" path="res://addons/imjp94.yafsm/scenes/StateMachineEditor.gd" id="2"]
+[ext_resource type="PackedScene" uid="uid://cflltb00e10be" path="res://addons/imjp94.yafsm/scenes/ContextMenu.tscn" id="3"]
+[ext_resource type="Script" path="res://addons/imjp94.yafsm/scenes/ParametersPanel.gd" id="4"]
+
+[node name="StateMachineEditor" type="Control"]
+visible = false
+clip_contents = true
+custom_minimum_size = Vector2i(0, 200)
+layout_mode = 3
+anchors_preset = 15
+anchor_right = 1.0
+anchor_bottom = 1.0
+grow_horizontal = 2
+grow_vertical = 2
+size_flags_horizontal = 3
+size_flags_vertical = 3
+focus_mode = 2
+mouse_filter = 1
+script = ExtResource("2")
+
+[node name="MarginContainer" type="MarginContainer" parent="."]
+visible = false
+layout_mode = 1
+anchors_preset = 15
+anchor_right = 1.0
+anchor_bottom = 1.0
+grow_horizontal = 2
+grow_vertical = 2
+size_flags_horizontal = 3
+size_flags_vertical = 3
+
+[node name="Panel" type="Panel" parent="MarginContainer"]
+layout_mode = 2
+offset_right = 1152.0
+offset_bottom = 648.0
+
+[node name="CreateNewStateMachine" type="Button" parent="MarginContainer"]
+layout_mode = 2
+offset_left = 473.0
+offset_top = 308.0
+offset_right = 679.0
+offset_bottom = 339.0
+size_flags_horizontal = 4
+size_flags_vertical = 4
+theme_override_colors/font_color = Color(0.87451, 0.87451, 0.87451, 1)
+text = "Create new StateMachine"
+
+[node name="ContextMenu" parent="." instance=ExtResource("3")]
+visible = false
+
+[node name="StateNodeContextMenu" parent="." instance=ExtResource("1")]
+visible = false
+
+[node name="SaveDialog" type="ConfirmationDialog" parent="."]
+
+[node name="ConvertToStateConfirmation" type="ConfirmationDialog" parent="."]
+dialog_text = "All nested states beneath it will be lost, are you sure about that?"
+dialog_autowrap = true
+
+[node name="ParametersPanel" type="MarginContainer" parent="."]
+visible = false
+layout_mode = 1
+anchors_preset = 3
+anchor_left = 1.0
+anchor_top = 1.0
+anchor_right = 1.0
+anchor_bottom = 1.0
+grow_horizontal = 0
+grow_vertical = 0
+script = ExtResource("4")
+
+[node name="PanelContainer" type="PanelContainer" parent="ParametersPanel"]
+layout_mode = 2
+offset_right = 113.0
+offset_bottom = 31.0
+
+[node name="MarginContainer" type="MarginContainer" parent="ParametersPanel/PanelContainer"]
+layout_mode = 2
+
+[node name="VBoxContainer" type="VBoxContainer" parent="ParametersPanel/PanelContainer/MarginContainer"]
+layout_mode = 2
+offset_right = 113.0
+offset_bottom = 31.0
+
+[node name="MarginContainer" type="MarginContainer" parent="ParametersPanel/PanelContainer/MarginContainer/VBoxContainer"]
+layout_mode = 2
+
+[node name="Button" type="Button" parent="ParametersPanel/PanelContainer/MarginContainer/VBoxContainer/MarginContainer"]
+layout_mode = 2
+offset_right = 113.0
+offset_bottom = 31.0
+size_flags_horizontal = 10
+text = "Show Params"
+
+[node name="GridContainer" type="GridContainer" parent="ParametersPanel/PanelContainer/MarginContainer/VBoxContainer"]
+visible = false
+layout_mode = 2
+columns = 4

addons/imjp94.yafsm/scenes/StateMachineEditorLayer.gd

@@ -0,0 +1,149 @@
+@tool
+extends "res://addons/imjp94.yafsm/scenes/flowchart/FlowChartLayer.gd"
+
+const Utils = preload("res://addons/imjp94.yafsm/scripts/Utils.gd")
+const StateNode = preload("res://addons/imjp94.yafsm/scenes/state_nodes/StateNode.tscn")
+const StateNodeScript = preload("res://addons/imjp94.yafsm/scenes/state_nodes/StateNode.gd")
+const StateDirectory = preload("../src/StateDirectory.gd")
+
+var editor_accent_color: = Color.WHITE:
+	set = set_editor_accent_color
+var editor_complementary_color = Color.WHITE
+
+var state_machine
+var tween_lines
+var tween_labels
+var tween_nodes
+
+
+func debug_update(current_state, parameters, local_parameters):
+	_init_tweens()
+	if not state_machine:
+		return
+	var current_dir = StateDirectory.new(current_state)
+	var transitions = state_machine.transitions.get(current_state, {})
+	if current_dir.is_nested():
+		transitions = state_machine.transitions.get(current_dir.get_end(), {})
+	for transition in transitions.values():
+		# Check all possible transitions from current state, update labels, color them accordingly
+		var line = content_lines.get_node_or_null(NodePath("%s>%s" % [transition.from, transition.to]))
+		if line:
+			# Blinking alpha of TransitionLine
+			var color1 = Color.WHITE
+			color1.a = 0.1
+			var color2 = Color.WHITE
+			color2.a = 0.5
+			if line.self_modulate == color1:
+				tween_lines.tween_property(line, "self_modulate", color2, 0.5)
+			elif line.self_modulate == color2:
+				tween_lines.tween_property(line, "self_modulate", color1, 0.5)
+			elif line.self_modulate == Color.WHITE:
+				tween_lines.tween_property(line, "self_modulate", color2, 0.5)
+			# Update TransitionLine condition labels
+			for condition in transition.conditions.values():
+				if not ("value" in condition): # Ignore trigger
+					continue
+				var value = parameters.get(str(condition.name))
+				value = str(value) if value != null else "?"
+				var label = line.vbox.get_node_or_null(NodePath(str(condition.name)))
+				var override_template_var = line._template_var.get(str(condition.name))
+				if override_template_var == null:
+					override_template_var = {}
+					line._template_var[str(condition.name)] = override_template_var
+				override_template_var["value"] = str(value)
+				line.update_label()
+				# Condition label color based on comparation
+				var cond_1: bool = condition.compare(parameters.get(str(condition.name)))
+				var cond_2: bool = condition.compare(local_parameters.get(str(condition.name)))
+				if cond_1 or cond_2:
+					tween_labels.tween_property(label, "self_modulate", Color.GREEN.lightened(0.5), 0.01)
+				else:
+					tween_labels.tween_property(label, "self_modulate", Color.RED.lightened(0.5), 0.01)
+	_start_tweens()
+
+func debug_transit_out(from, to):
+	_init_tweens()
+	var from_dir = StateDirectory.new(from)
+	var to_dir = StateDirectory.new(to)
+	var from_node = content_nodes.get_node_or_null(NodePath(from_dir.get_end()))
+	if from_node != null:
+		tween_nodes.tween_property(from_node, "self_modulate", editor_complementary_color, 0.01)
+		tween_nodes.tween_property(from_node, "self_modulate", Color.WHITE, 1)
+	var transitions = state_machine.transitions.get(from, {})
+	if from_dir.is_nested():
+		transitions = state_machine.transitions.get(from_dir.get_end(), {})
+	# Fade out color of StateNode
+	for transition in transitions.values():
+		var line = content_lines.get_node_or_null(NodePath("%s>%s" % [transition.from, transition.to]))
+		if line:
+			line.template = "{condition_name} {condition_comparation} {condition_value}"
+			line.update_label()
+			if transition.to == to_dir.get_end():
+				tween_lines.tween_property(line, "self_modulate", editor_complementary_color, 0.01)
+				tween_lines.tween_property(line, "self_modulate", Color.WHITE, 1).set_trans(Tween.TRANS_EXPO).set_ease(Tween.EASE_IN)
+				# Highlight all the conditions of the transition that just happened
+				for condition in transition.conditions.values():
+					if not ("value" in condition): # Ignore trigger
+						continue
+					var label = line.vbox.get_node_or_null(NodePath(condition.name))
+					tween_labels.tween_property(label, "self_modulate", editor_complementary_color, 0.01)
+					tween_labels.tween_property(label, "self_modulate", Color.WHITE, 1)
+			else:
+				tween_lines.tween_property(line, "self_modulate", Color.WHITE, 0.1)
+				# Revert color of TransitionLine condition labels
+				for condition in transition.conditions.values():
+					if not ("value" in condition): # Ignore trigger
+						continue
+					var label = line.vbox.get_node_or_null(NodePath(condition.name))
+					if label.self_modulate != Color.WHITE:
+						tween_labels.tween_property(label, "self_modulate", Color.WHITE, 0.5)
+	if from_dir.is_nested() and from_dir.is_exit():
+		# Transition from nested state
+		transitions = state_machine.transitions.get(from_dir.get_base(), {})
+		tween_lines.set_parallel(true)
+		for transition in transitions.values():
+			var line = content_lines.get_node_or_null(NodePath("%s>%s" % [transition.from, transition.to]))
+			if line:
+				tween_lines.tween_property(line, "self_modulate", editor_complementary_color.lightened(0.5), 0.1)
+		for transition in transitions.values():
+			var line = content_lines.get_node_or_null(NodePath("%s>%s" % [transition.from, transition.to]))
+			if line:
+				tween_lines.tween_property(line, "self_modulate", Color.WHITE, 0.1)
+	_start_tweens()
+
+func debug_transit_in(from, to):
+	_init_tweens()
+	var to_dir = StateDirectory.new(to)
+	var to_node = content_nodes.get_node_or_null(NodePath(to_dir.get_end()))
+	if to_node:
+		tween_nodes.tween_property(to_node, "self_modulate", editor_complementary_color, 0.5)
+	var transitions = state_machine.transitions.get(to, {})
+	if to_dir.is_nested():
+		transitions = state_machine.transitions.get(to_dir.get_end(), {})
+	# Change string template for current TransitionLines
+	for transition in transitions.values():
+		var line = content_lines.get_node_or_null(NodePath("%s>%s" % [transition.from, transition.to]))
+		line.template = "{condition_name} {condition_comparation} {condition_value}({value})"
+	_start_tweens()
+
+func set_editor_accent_color(color):
+	editor_accent_color = color
+	editor_complementary_color = Utils.get_complementary_color(color)
+
+
+func _init_tweens():
+	tween_lines = get_tree().create_tween()
+	tween_lines.stop()
+	tween_labels = get_tree().create_tween()
+	tween_labels.stop()
+	tween_nodes = get_tree().create_tween()
+	tween_nodes.stop()
+
+
+func _start_tweens():
+	tween_lines.tween_interval(0.001)
+	tween_lines.play()
+	tween_labels.tween_interval(0.001)
+	tween_labels.play()
+	tween_nodes.tween_interval(0.001)
+	tween_nodes.play()

addons/imjp94.yafsm/scenes/StateNodeContextMenu.tscn

@@ -0,0 +1,17 @@
+[gd_scene format=3 uid="uid://ccv81pntbud75"]
+
+[node name="StateNodeContextMenu" type="PopupMenu"]
+size = Vector2i(154, 120)
+visible = true
+item_count = 5
+item_0/text = "Copy"
+item_0/id = 0
+item_1/text = "Duplicate"
+item_1/id = 1
+item_2/text = "Delete"
+item_2/id = 4
+item_3/text = ""
+item_3/id = 2
+item_3/separator = true
+item_4/text = "Convert to State"
+item_4/id = 3

addons/imjp94.yafsm/scenes/condition_editors/BoolConditionEditor.gd

@@ -0,0 +1,22 @@
+@tool
+extends "ValueConditionEditor.gd"
+
+@onready var boolean_value = $MarginContainer/BooleanValue
+
+func _ready():
+	super._ready()
+	
+	boolean_value.pressed.connect(_on_boolean_value_pressed)
+
+
+func _on_value_changed(new_value):
+	if boolean_value.button_pressed != new_value:
+		boolean_value.button_pressed = new_value
+
+func _on_boolean_value_pressed():
+	change_value_action(condition.value, boolean_value.button_pressed)
+
+func _on_condition_changed(new_condition):
+	super._on_condition_changed(new_condition)
+	if new_condition:
+		boolean_value.button_pressed = new_condition.value

addons/imjp94.yafsm/scenes/condition_editors/BoolConditionEditor.tscn

@@ -0,0 +1,35 @@
+[gd_scene load_steps=3 format=3 uid="uid://bmpwx6h3ckekr"]
+
+[ext_resource type="PackedScene" uid="uid://blnscdhcxvpmk" path="res://addons/imjp94.yafsm/scenes/condition_editors/ValueConditionEditor.tscn" id="1"]
+[ext_resource type="Script" path="res://addons/imjp94.yafsm/scenes/condition_editors/BoolConditionEditor.gd" id="2"]
+
+[node name="BoolConditionEditor" instance=ExtResource("1")]
+script = ExtResource("2")
+
+[node name="Name" parent="." index="0"]
+layout_mode = 2
+
+[node name="Comparation" parent="." index="1"]
+layout_mode = 2
+
+[node name="PopupMenu" parent="Comparation" index="0"]
+item_count = 2
+
+[node name="MarginContainer" parent="." index="2"]
+layout_mode = 2
+offset_top = 3.0
+offset_right = 146.0
+offset_bottom = 27.0
+size_flags_horizontal = 3
+size_flags_vertical = 4
+
+[node name="BooleanValue" type="CheckButton" parent="MarginContainer" index="0"]
+layout_mode = 2
+offset_right = 44.0
+offset_bottom = 24.0
+size_flags_horizontal = 6
+
+[node name="Remove" parent="." index="3"]
+layout_mode = 2
+offset_left = 150.0
+offset_right = 176.0

addons/imjp94.yafsm/scenes/condition_editors/ConditionEditor.gd

@@ -0,0 +1,72 @@
+@tool
+extends HBoxContainer
+
+@onready var name_edit = $Name
+@onready var remove = $Remove
+
+var undo_redo
+
+var condition:
+	set = set_condition
+
+
+func _ready():
+	name_edit.text_submitted.connect(_on_name_edit_text_submitted)
+	name_edit.focus_entered.connect(_on_name_edit_focus_entered)
+	name_edit.focus_exited.connect(_on_name_edit_focus_exited)
+	name_edit.text_changed.connect(_on_name_edit_text_changed)
+	set_process_input(false)
+
+func _input(event):
+	if event is InputEventMouseButton:
+		if event.pressed:
+			if get_viewport().gui_get_focus_owner() == name_edit:
+				var local_event = name_edit.make_input_local(event)
+				if not name_edit.get_rect().has_point(local_event.position):
+					name_edit.release_focus()
+
+func _on_name_edit_text_changed(new_text):
+	# name_edit.release_focus()
+	if condition.name == new_text: # Avoid infinite loop
+		return
+
+	rename_edit_action(new_text)
+
+func _on_name_edit_focus_entered():
+	set_process_input(true)
+
+func _on_name_edit_focus_exited():
+	set_process_input(false)
+	if condition.name == name_edit.text:
+		return
+
+	rename_edit_action(name_edit.text)
+
+func _on_name_edit_text_submitted(new_text):
+	name_edit.tooltip_text = new_text
+
+func change_name_edit(from, to):
+	var transition = get_parent().get_parent().get_parent().transition # TODO: Better way to get Transition object
+	if transition.change_condition_name(from, to):
+		if name_edit.text != to: # Manually update name_edit.text, in case called from undo_redo
+			name_edit.text = to
+	else:
+		name_edit.text = from
+		push_warning("Change Condition name_edit from (%s) to (%s) failed, name_edit existed" % [from, to])
+
+func rename_edit_action(new_name_edit):
+	var old_name_edit = condition.name
+	undo_redo.create_action("Rename_edit Condition")
+	undo_redo.add_do_method(self, "change_name_edit", old_name_edit, new_name_edit)
+	undo_redo.add_undo_method(self, "change_name_edit", new_name_edit, old_name_edit)
+	undo_redo.commit_action()
+
+func _on_condition_changed(new_condition):
+	if new_condition:
+		name_edit.text = new_condition.name
+		name_edit.tooltip_text = name_edit.text
+
+func set_condition(c):
+	if condition != c:
+		condition = c
+		_on_condition_changed(c)

addons/imjp94.yafsm/scenes/condition_editors/ConditionEditor.tscn

@@ -0,0 +1,24 @@
+[gd_scene load_steps=3 format=3 uid="uid://cie8lb6ww58ck"]
+
+[ext_resource type="Script" path="res://addons/imjp94.yafsm/scenes/condition_editors/ConditionEditor.gd" id="1"]
+[ext_resource type="Texture2D" uid="uid://l78bjwo7shm" path="res://addons/imjp94.yafsm/assets/icons/close-white-18dp.svg" id="2"]
+
+[node name="ConditionEditor" type="HBoxContainer"]
+script = ExtResource("1")
+
+[node name="Name" type="LineEdit" parent="."]
+layout_mode = 2
+offset_right = 67.0
+offset_bottom = 31.0
+size_flags_horizontal = 3
+size_flags_vertical = 4
+text = "Param"
+
+[node name="Remove" type="Button" parent="."]
+layout_mode = 2
+offset_left = 71.0
+offset_right = 97.0
+offset_bottom = 31.0
+size_flags_horizontal = 9
+icon = ExtResource("2")
+flat = true

addons/imjp94.yafsm/scenes/condition_editors/FloatConditionEditor.gd

@@ -0,0 +1,44 @@
+@tool
+extends "ValueConditionEditor.gd"
+
+@onready var float_value = $MarginContainer/FloatValue
+
+var _old_value = 0.0
+
+func _ready():
+	super._ready()
+	
+	float_value.text_submitted.connect(_on_float_value_text_submitted)
+	float_value.focus_entered.connect(_on_float_value_focus_entered)
+	float_value.focus_exited.connect(_on_float_value_focus_exited)
+	set_process_input(false)
+
+func _input(event):
+	super._input(event)
+	
+	if event is InputEventMouseButton:
+		if event.pressed:
+			if get_viewport().gui_get_focus_owner() == float_value:
+				var local_event = float_value.make_input_local(event)
+				if not float_value.get_rect().has_point(local_event.position):
+					float_value.release_focus()
+
+func _on_value_changed(new_value):
+	float_value.text = str(snapped(new_value, 0.01)).pad_decimals(2)
+
+func _on_float_value_text_submitted(new_text):
+	change_value_action(_old_value, float(new_text))
+	float_value.release_focus()
+
+func _on_float_value_focus_entered():
+	set_process_input(true)
+	_old_value = float(float_value.text)
+
+func _on_float_value_focus_exited():
+	set_process_input(false)
+	change_value_action(_old_value, float(float_value.text))
+
+func _on_condition_changed(new_condition):
+	super._on_condition_changed(new_condition)
+	if new_condition:
+		float_value.text = str(snapped(new_condition.value, 0.01)).pad_decimals(2)

addons/imjp94.yafsm/scenes/condition_editors/FloatConditionEditor.tscn

@@ -0,0 +1,26 @@
+[gd_scene load_steps=3 format=3 uid="uid://doq6lkdh20j15"]
+
+[ext_resource type="PackedScene" uid="uid://blnscdhcxvpmk" path="res://addons/imjp94.yafsm/scenes/condition_editors/ValueConditionEditor.tscn" id="1"]
+[ext_resource type="Script" path="res://addons/imjp94.yafsm/scenes/condition_editors/FloatConditionEditor.gd" id="2"]
+
+[node name="ValueConditionEditor" instance=ExtResource("1")]
+script = ExtResource("2")
+
+[node name="Comparation" parent="." index="1"]
+layout_mode = 2
+
+[node name="MarginContainer" parent="." index="2"]
+layout_mode = 2
+offset_right = 169.0
+size_flags_horizontal = 3
+size_flags_vertical = 4
+
+[node name="FloatValue" type="LineEdit" parent="MarginContainer" index="0"]
+layout_mode = 2
+offset_right = 67.0
+offset_bottom = 31.0
+size_flags_horizontal = 3
+
+[node name="Remove" parent="." index="3"]
+offset_left = 173.0
+offset_right = 199.0

addons/imjp94.yafsm/scenes/condition_editors/IntegerConditionEditor.gd

@@ -0,0 +1,45 @@
+@tool
+extends "ValueConditionEditor.gd"
+
+@onready var integer_value = $MarginContainer/IntegerValue
+
+var _old_value = 0
+
+
+func _ready():
+	super._ready()
+	
+	integer_value.text_submitted.connect(_on_integer_value_text_submitted)
+	integer_value.focus_entered.connect(_on_integer_value_focus_entered)
+	integer_value.focus_exited.connect(_on_integer_value_focus_exited)
+	set_process_input(false)
+
+func _input(event):
+	super._input(event)
+	
+	if event is InputEventMouseButton:
+		if event.pressed:
+			if get_viewport().gui_get_focus_owner() == integer_value:
+				var local_event = integer_value.make_input_local(event)
+				if not integer_value.get_rect().has_point(local_event.position):
+					integer_value.release_focus()
+
+func _on_value_changed(new_value):
+	integer_value.text = str(new_value)
+
+func _on_integer_value_text_submitted(new_text):
+	change_value_action(_old_value, int(new_text))
+	integer_value.release_focus()
+
+func _on_integer_value_focus_entered():
+	set_process_input(true)
+	_old_value = int(integer_value.text)
+
+func _on_integer_value_focus_exited():
+	set_process_input(false)
+	change_value_action(_old_value, int(integer_value.text))
+
+func _on_condition_changed(new_condition):
+	super._on_condition_changed(new_condition)
+	if new_condition:
+		integer_value.text = str(new_condition.value)

addons/imjp94.yafsm/scenes/condition_editors/IntegerConditionEditor.tscn

@@ -0,0 +1,26 @@
+[gd_scene load_steps=3 format=3 uid="uid://d1ib30424prpf"]
+
+[ext_resource type="PackedScene" uid="uid://blnscdhcxvpmk" path="res://addons/imjp94.yafsm/scenes/condition_editors/ValueConditionEditor.tscn" id="1"]
+[ext_resource type="Script" path="res://addons/imjp94.yafsm/scenes/condition_editors/IntegerConditionEditor.gd" id="2"]
+
+[node name="IntegerConditionEditor" instance=ExtResource("1")]
+script = ExtResource("2")
+
+[node name="Comparation" parent="." index="1"]
+layout_mode = 2
+
+[node name="MarginContainer" parent="." index="2"]
+layout_mode = 2
+offset_right = 169.0
+size_flags_horizontal = 3
+size_flags_vertical = 4
+
+[node name="IntegerValue" type="LineEdit" parent="MarginContainer" index="0"]
+layout_mode = 2
+offset_right = 67.0
+offset_bottom = 31.0
+size_flags_horizontal = 3
+
+[node name="Remove" parent="." index="3"]
+offset_left = 173.0
+offset_right = 199.0

addons/imjp94.yafsm/scenes/condition_editors/StringConditionEditor.gd

@@ -0,0 +1,46 @@
+@tool
+extends "res://addons/imjp94.yafsm/scenes/condition_editors/ValueConditionEditor.gd"
+
+
+@onready var string_value = $MarginContainer/StringValue
+
+var _old_value = 0
+
+
+func _ready():
+	super._ready()
+	
+	string_value.text_submitted.connect(_on_string_value_text_submitted)
+	string_value.focus_entered.connect(_on_string_value_focus_entered)
+	string_value.focus_exited.connect(_on_string_value_focus_exited)
+	set_process_input(false)
+
+func _input(event):
+	super._input(event)
+	
+	if event is InputEventMouseButton:
+		if event.pressed:
+			if get_viewport().gui_get_focus_owner() == string_value:
+				var local_event = string_value.make_input_local(event)
+				if not string_value.get_rect().has_point(local_event.position):
+					string_value.release_focus()
+
+func _on_value_changed(new_value):
+	string_value.text = new_value
+
+func _on_string_value_text_submitted(new_text):
+	change_value_action(_old_value, new_text)
+	string_value.release_focus()
+
+func _on_string_value_focus_entered():
+	set_process_input(true)
+	_old_value = string_value.text
+
+func _on_string_value_focus_exited():
+	set_process_input(false)
+	change_value_action(_old_value, string_value.text)
+
+func _on_condition_changed(new_condition):
+	super._on_condition_changed(new_condition)
+	if new_condition:
+		string_value.text = new_condition.value

addons/imjp94.yafsm/scenes/condition_editors/StringConditionEditor.tscn

@@ -0,0 +1,29 @@
+[gd_scene load_steps=3 format=3 uid="uid://qfw0snt5kss6"]
+
+[ext_resource type="PackedScene" uid="uid://blnscdhcxvpmk" path="res://addons/imjp94.yafsm/scenes/condition_editors/ValueConditionEditor.tscn" id="1"]
+[ext_resource type="Script" path="res://addons/imjp94.yafsm/scenes/condition_editors/StringConditionEditor.gd" id="2"]
+
+[node name="StringConditionEditor" instance=ExtResource("1")]
+script = ExtResource("2")
+
+[node name="Comparation" parent="." index="1"]
+layout_mode = 2
+
+[node name="PopupMenu" parent="Comparation" index="0"]
+item_count = 2
+
+[node name="MarginContainer" parent="." index="2"]
+layout_mode = 2
+offset_right = 169.0
+size_flags_horizontal = 3
+size_flags_vertical = 4
+
+[node name="StringValue" type="LineEdit" parent="MarginContainer" index="0"]
+layout_mode = 2
+offset_right = 67.0
+offset_bottom = 31.0
+size_flags_horizontal = 3
+
+[node name="Remove" parent="." index="3"]
+offset_left = 173.0
+offset_right = 199.0

addons/imjp94.yafsm/scenes/condition_editors/ValueConditionEditor.gd

@@ -0,0 +1,57 @@
+@tool
+extends "ConditionEditor.gd"
+const Utils = preload("../../scripts/Utils.gd")
+const Comparation = preload("../../src/conditions/ValueCondition.gd").Comparation
+
+@onready var comparation_button = $Comparation
+@onready var comparation_popup_menu = $Comparation/PopupMenu
+
+
+func _ready():
+	super._ready()
+	
+	comparation_button.pressed.connect(_on_comparation_button_pressed)
+	comparation_popup_menu.id_pressed.connect(_on_comparation_popup_menu_id_pressed)
+
+func _on_comparation_button_pressed():
+	Utils.popup_on_target(comparation_popup_menu, comparation_button)
+
+func _on_comparation_popup_menu_id_pressed(id):
+	change_comparation_action(id)
+
+func _on_condition_changed(new_condition):
+	super._on_condition_changed(new_condition)
+	if new_condition:
+		comparation_button.text = comparation_popup_menu.get_item_text(new_condition.comparation)
+
+func _on_value_changed(new_value):
+	pass
+
+func change_comparation(id):
+	if id > Comparation.size() - 1:
+		push_error("Unexpected id(%d) from PopupMenu" % id)
+		return
+	condition.comparation = id
+	comparation_button.text = comparation_popup_menu.get_item_text(id)
+
+func change_comparation_action(id):
+	var from = condition.comparation
+	var to = id
+	
+	undo_redo.create_action("Change Condition Comparation")
+	undo_redo.add_do_method(self, "change_comparation", to)
+	undo_redo.add_undo_method(self, "change_comparation", from)
+	undo_redo.commit_action()
+
+func set_value(v):
+	if condition.value != v:
+		condition.value = v
+		_on_value_changed(v)
+
+func change_value_action(from, to):
+	if from == to:
+		return
+	undo_redo.create_action("Change Condition Value")
+	undo_redo.add_do_method(self, "set_value", to)
+	undo_redo.add_undo_method(self, "set_value", from)
+	undo_redo.commit_action()

addons/imjp94.yafsm/scenes/condition_editors/ValueConditionEditor.tscn

@@ -0,0 +1,42 @@
+[gd_scene load_steps=3 format=3 uid="uid://blnscdhcxvpmk"]
+
+[ext_resource type="PackedScene" uid="uid://cie8lb6ww58ck" path="res://addons/imjp94.yafsm/scenes/condition_editors/ConditionEditor.tscn" id="1"]
+[ext_resource type="Script" path="res://addons/imjp94.yafsm/scenes/condition_editors/ValueConditionEditor.gd" id="2"]
+
+[node name="ValueConditionEditor" instance=ExtResource("1")]
+script = ExtResource("2")
+
+[node name="Comparation" type="Button" parent="." index="1"]
+layout_mode = 2
+offset_left = 71.0
+offset_right = 98.0
+offset_bottom = 31.0
+size_flags_horizontal = 5
+size_flags_vertical = 4
+text = "=="
+
+[node name="PopupMenu" type="PopupMenu" parent="Comparation" index="0"]
+item_count = 6
+item_0/text = "=="
+item_0/id = 0
+item_1/text = "!="
+item_1/id = 1
+item_2/text = ">"
+item_2/id = 2
+item_3/text = "<"
+item_3/id = 3
+item_4/text = "≥"
+item_4/id = 4
+item_5/text = "≤"
+item_5/id = 5
+
+[node name="MarginContainer" type="MarginContainer" parent="." index="2"]
+layout_mode = 2
+offset_left = 102.0
+offset_right = 102.0
+offset_bottom = 31.0
+
+[node name="Remove" parent="." index="3"]
+offset_left = 106.0
+offset_right = 132.0
+tooltip_text = "Remove Condition"

addons/imjp94.yafsm/scenes/flowchart/FlowChart.gd

@@ -0,0 +1,681 @@
+@tool
+extends Control
+
+const Utils = preload("res://addons/imjp94.yafsm/scripts/Utils.gd")
+const CohenSutherland = Utils.CohenSutherland
+const FlowChartNode = preload("FlowChartNode.gd")
+const FlowChartNodeScene = preload("FlowChartNode.tscn")
+const FlowChartLine = preload("FlowChartLine.gd")
+const FlowChartLineScene = preload("FlowChartLine.tscn")
+const FlowChartLayer = preload("FlowChartLayer.gd")
+const FlowChartGrid = preload("FlowChartGrid.gd")
+const Connection = FlowChartLayer.Connection
+
+signal connection(from, to, line) # When a connection established
+signal disconnection(from, to, line) # When a connection broken
+signal node_selected(node) # When a node selected
+signal node_deselected(node) # When a node deselected
+signal dragged(node, distance) # When a node dragged
+
+# Margin of content from edge of FlowChart
+@export var scroll_margin: = 50
+# Offset between two line that interconnecting
+@export var interconnection_offset: = 10
+# Snap amount
+@export var snap: = 20
+# Zoom amount
+@export var zoom: = 1.0:
+	set = set_zoom
+@export var zoom_step: = 0.2
+@export var max_zoom: = 2.0
+@export var min_zoom: = 0.5
+
+var grid = FlowChartGrid.new() # Grid
+var content = Control.new() # Root node that hold anything drawn in the flowchart
+var current_layer
+var h_scroll = HScrollBar.new()
+var v_scroll = VScrollBar.new()
+var top_bar = VBoxContainer.new()
+var gadget = HBoxContainer.new() # Root node of top overlay controls
+var zoom_minus = Button.new()
+var zoom_reset = Button.new()
+var zoom_plus = Button.new()
+var snap_button = Button.new()
+var snap_amount = SpinBox.new()
+
+var is_snapping = true
+var can_gui_select_node = true
+var can_gui_delete_node = true
+var can_gui_connect_node = true
+
+var _is_connecting = false
+var _current_connection
+var _is_dragging = false
+var _is_dragging_node = false
+var _drag_start_pos = Vector2.ZERO
+var _drag_end_pos = Vector2.ZERO
+var _drag_origins = []
+var _selection = []
+var _copying_nodes = []
+
+var selection_stylebox = StyleBoxFlat.new()
+var grid_major_color = Color(1, 1, 1, 0.2)
+var grid_minor_color = Color(1, 1, 1, 0.05)
+	
+
+func _init():
+	
+	focus_mode = FOCUS_ALL
+	selection_stylebox.bg_color = Color(0, 0, 0, 0.3)
+	selection_stylebox.set_border_width_all(1)
+
+	self.z_index = 0
+
+	content.mouse_filter = MOUSE_FILTER_IGNORE
+	add_child(content)
+	content.z_index = 1
+
+	grid.mouse_filter = MOUSE_FILTER_IGNORE
+	content.add_child.call_deferred(grid)
+	grid.z_index = -1
+
+	add_child(h_scroll)
+	h_scroll.set_anchors_and_offsets_preset(PRESET_BOTTOM_WIDE)
+	h_scroll.value_changed.connect(_on_h_scroll_changed)
+	h_scroll.gui_input.connect(_on_h_scroll_gui_input)
+
+	add_child(v_scroll)
+	v_scroll.set_anchors_and_offsets_preset(PRESET_RIGHT_WIDE)
+	v_scroll.value_changed.connect(_on_v_scroll_changed)
+	v_scroll.gui_input.connect(_on_v_scroll_gui_input)
+
+	h_scroll.offset_right = -v_scroll.size.x
+	v_scroll.offset_bottom = -h_scroll.size.y
+
+	h_scroll.min_value = 0
+	v_scroll.max_value = 0
+
+	add_layer_to(content)
+	select_layer_at(0)
+
+	top_bar.set_anchors_and_offsets_preset(PRESET_TOP_WIDE)
+	top_bar.mouse_filter = MOUSE_FILTER_IGNORE
+	add_child(top_bar)
+
+	gadget.mouse_filter = MOUSE_FILTER_IGNORE
+	top_bar.add_child(gadget)
+
+	zoom_minus.flat = true
+	zoom_minus.tooltip_text = "Zoom Out"
+	zoom_minus.pressed.connect(_on_zoom_minus_pressed)
+	zoom_minus.focus_mode = FOCUS_NONE
+	gadget.add_child(zoom_minus)
+
+	zoom_reset.flat = true
+	zoom_reset.tooltip_text = "Zoom Reset"
+	zoom_reset.pressed.connect(_on_zoom_reset_pressed)
+	zoom_reset.focus_mode = FOCUS_NONE
+	gadget.add_child(zoom_reset)
+
+	zoom_plus.flat = true
+	zoom_plus.tooltip_text = "Zoom In"
+	zoom_plus.pressed.connect(_on_zoom_plus_pressed)
+	zoom_plus.focus_mode = FOCUS_NONE
+	gadget.add_child(zoom_plus)
+
+	snap_button.flat = true
+	snap_button.toggle_mode = true
+	snap_button.tooltip_text = "Enable snap and show grid"
+	snap_button.pressed.connect(_on_snap_button_pressed)
+	snap_button.button_pressed = true
+	snap_button.focus_mode = FOCUS_NONE
+	gadget.add_child(snap_button)
+
+	snap_amount.value = snap
+	snap_amount.value_changed.connect(_on_snap_amount_value_changed)
+	gadget.add_child(snap_amount)
+
+func _on_h_scroll_gui_input(event):
+	if event is InputEventMouseButton:
+		var v = (h_scroll.max_value - h_scroll.min_value) * 0.01 # Scroll at 0.1% step
+		match event.button_index:
+			MOUSE_BUTTON_WHEEL_UP:
+				h_scroll.value -= v
+			MOUSE_BUTTON_WHEEL_DOWN:
+				h_scroll.value += v
+
+func _on_v_scroll_gui_input(event):
+	if event is InputEventMouseButton:
+		var v = (v_scroll.max_value - v_scroll.min_value) * 0.01 # Scroll at 0.1% step
+		match event.button_index:
+			MOUSE_BUTTON_WHEEL_UP:
+				v_scroll.value -= v # scroll left
+			MOUSE_BUTTON_WHEEL_DOWN:
+				v_scroll.value += v # scroll right
+
+func _on_h_scroll_changed(value):
+	content.position.x = -value
+
+func _on_v_scroll_changed(value):
+	content.position.y = -value
+
+func set_zoom(v):
+	zoom = clampf(v, min_zoom, max_zoom)
+	content.scale = Vector2.ONE * zoom
+	queue_redraw()
+	grid.queue_redraw()
+
+func _on_zoom_minus_pressed():
+	set_zoom(zoom - zoom_step)
+	queue_redraw()
+
+func _on_zoom_reset_pressed():
+	set_zoom(1.0)
+	queue_redraw()
+
+func _on_zoom_plus_pressed():
+	set_zoom(zoom + zoom_step)
+	queue_redraw()
+
+func _on_snap_button_pressed():
+	is_snapping = snap_button.button_pressed
+	queue_redraw()
+
+func _on_snap_amount_value_changed(value):
+	snap = value
+	queue_redraw()
+
+func _draw():
+	# Update scrolls
+	var content_rect: Rect2 = get_scroll_rect(current_layer, 0)
+	content.pivot_offset = content_rect.size / 2.0 # Scale from center
+	var flowchart_rect: Rect2 = get_rect()
+	# ENCLOSE CONDITIONS
+	var is_content_enclosed = (flowchart_rect.size.x >= content_rect.size.x)
+	is_content_enclosed = is_content_enclosed and (flowchart_rect.size.y >= content_rect.size.y)
+	is_content_enclosed = is_content_enclosed and (flowchart_rect.position.x <= content_rect.position.x)
+	is_content_enclosed = is_content_enclosed and (flowchart_rect.position.y >= content_rect.position.y)
+	if not is_content_enclosed or (h_scroll.min_value==h_scroll.max_value) or (v_scroll.min_value==v_scroll.max_value):
+		var h_min = 0 # content_rect.position.x - scroll_margin/2 - content_rect.get_center().x/2
+		var h_max = content_rect.size.x - content_rect.position.x - size.x + scroll_margin + content_rect.get_center().x
+		var v_min = 0 # content_rect.position.y - scroll_margin/2 - content_rect.get_center().y/2
+		var v_max = content_rect.size.y - content_rect.position.y - size.y + scroll_margin + content_rect.get_center().y
+		if h_min == h_max: # Otherwise scroll bar will complain no ratio
+			h_min -= 0.1
+			h_max += 0.1
+		if v_min == v_max: # Otherwise scroll bar will complain no ratio
+			v_min -= 0.1
+			v_max += 0.1
+		h_scroll.min_value = h_min
+		h_scroll.max_value = h_max
+		h_scroll.page = content_rect.size.x / 100
+		v_scroll.min_value = v_min
+		v_scroll.max_value = v_max
+		v_scroll.page = content_rect.size.y / 100
+
+	# Draw selection box
+	if not _is_dragging_node and not _is_connecting:
+		var selection_box_rect = get_selection_box_rect()
+		draw_style_box(selection_stylebox, selection_box_rect)
+
+	if is_snapping:
+		grid.visible = true
+		grid.queue_redraw()
+	else:
+		grid.visible = false
+
+	# Debug draw
+	# for node in content_nodes.get_children():
+	# 	var rect = get_transform() * (content.get_transform() * (node.get_rect()))
+	# 	draw_style_box(selection_stylebox, rect)
+
+	# var connection_list = get_connection_list()
+	# for i in connection_list.size():
+	# 	var connection = _connections[connection_list[i].from][connection_list[i].to]
+	# 	# Line's offset along its down-vector
+	# 	var line_local_up_offset = connection.line.position - connection.line.get_transform() * (Vector2.UP * connection.offset)
+	# 	var from_pos = content.get_transform() * (connection.get_from_pos() + line_local_up_offset)
+	# 	var to_pos = content.get_transform() * (connection.get_to_pos() + line_local_up_offset)
+	# 	draw_line(from_pos, to_pos, Color.yellow)
+
+func _gui_input(event):
+
+	var OS_KEY_DELETE = KEY_BACKSPACE if ( ["macOS", "OSX"].has(OS.get_name()) ) else KEY_DELETE
+	if event is InputEventKey:
+		match event.keycode:
+			OS_KEY_DELETE:
+				if event.pressed and can_gui_delete_node:
+					# Delete nodes
+					for node in _selection.duplicate():
+						if node is FlowChartLine:
+							# TODO: More efficient way to get connection from Line node
+							for connections_from in current_layer._connections.duplicate().values():
+								for connection in connections_from.duplicate().values():
+									if connection.line == node:
+										disconnect_node(current_layer, connection.from_node.name, connection.to_node.name).queue_free()
+						elif node is FlowChartNode:
+							remove_node(current_layer, node.name)
+							for connection_pair in current_layer.get_connection_list():
+								if connection_pair.from == node.name or connection_pair.to == node.name:
+									disconnect_node(current_layer, connection_pair.from, connection_pair.to).queue_free()
+					accept_event()
+			KEY_C:
+				if event.pressed and event.ctrl_pressed:
+					# Copy node
+					_copying_nodes = _selection.duplicate()
+					accept_event()
+			KEY_D:
+				if event.pressed and event.ctrl_pressed:
+					# Duplicate node directly from selection
+					duplicate_nodes(current_layer, _selection.duplicate())
+					accept_event()
+			KEY_V:
+				if event.pressed and event.ctrl_pressed:
+					# Paste node from _copying_nodes
+					duplicate_nodes(current_layer, _copying_nodes)
+					accept_event()
+
+	if event is InputEventMouseMotion:
+		match event.button_mask:
+			MOUSE_BUTTON_MASK_MIDDLE:
+				# Panning
+				h_scroll.value -= event.relative.x
+				v_scroll.value -= event.relative.y
+				queue_redraw()
+			MOUSE_BUTTON_LEFT:
+				# Dragging
+				if _is_dragging:
+					if _is_connecting:
+						# Connecting
+						if _current_connection:
+							var pos = content_position(get_local_mouse_position())
+							var clip_rects = [_current_connection.from_node.get_rect()]
+							
+							# Snapping connecting line
+							for i in current_layer.content_nodes.get_child_count():
+								var child = current_layer.content_nodes.get_child(current_layer.content_nodes.get_child_count()-1 - i) # Inverse order to check from top to bottom of canvas
+								if child is FlowChartNode and child.name != _current_connection.from_node.name:
+									if _request_connect_to(current_layer, child.name):
+										if child.get_rect().has_point(pos):
+											pos = child.position + child.size / 2
+											clip_rects.append(child.get_rect())
+											break
+							_current_connection.line.join(_current_connection.get_from_pos(), pos, Vector2.ZERO, clip_rects)
+					elif _is_dragging_node:
+						# Dragging nodes
+						var dragged = content_position(_drag_end_pos) - content_position(_drag_start_pos)
+						for i in _selection.size():
+							var selected = _selection[i]
+							if not (selected is FlowChartNode):
+								continue
+							selected.position = (_drag_origins[i] + selected.size / 2.0 + dragged)
+							selected.modulate.a = 0.3
+							if is_snapping:
+								selected.position = selected.position.snapped(Vector2.ONE * snap)
+							selected.position -= selected.size / 2.0 
+							_on_node_dragged(current_layer, selected, dragged)
+							emit_signal("dragged", selected, dragged)
+							# Update connection pos
+							for from in current_layer._connections:
+								var connections_from = current_layer._connections[from]
+								for to in connections_from:
+									if from == selected.name or to == selected.name:
+										var connection = current_layer._connections[from][to]
+										connection.join()
+					_drag_end_pos = get_local_mouse_position()
+					queue_redraw()
+
+	if event is InputEventMouseButton:
+		match event.button_index:
+			MOUSE_BUTTON_MIDDLE:
+				# Reset zoom
+				if event.double_click:
+					set_zoom(1.0)
+					queue_redraw()
+			MOUSE_BUTTON_WHEEL_UP:
+				# Zoom in
+				set_zoom(zoom + zoom_step/10)
+				queue_redraw()
+			MOUSE_BUTTON_WHEEL_DOWN:
+				# Zoom out
+				set_zoom(zoom - zoom_step/10)
+				queue_redraw()
+			MOUSE_BUTTON_LEFT:
+				# Hit detection
+				var hit_node
+				for i in current_layer.content_nodes.get_child_count():
+					var child = current_layer.content_nodes.get_child(current_layer.content_nodes.get_child_count()-1 - i) # Inverse order to check from top to bottom of canvas
+					if child is FlowChartNode:
+						if child.get_rect().has_point(content_position(get_local_mouse_position())):
+							hit_node = child
+							break
+				if not hit_node:
+					# Test Line
+					# Refer https://github.com/godotengine/godot/blob/master/editor/plugins/animation_state_machine_editor.cpp#L187
+					var closest = -1
+					var closest_d = 1e20
+					var connection_list = get_connection_list()
+					for i in connection_list.size():
+						var connection = current_layer._connections[connection_list[i].from][connection_list[i].to]
+						# Line's offset along its down-vector
+						var line_local_up_offset = connection.line.position - connection.line.get_transform()*(Vector2.DOWN * connection.offset)
+						var from_pos = connection.get_from_pos() + line_local_up_offset
+						var to_pos = connection.get_to_pos() + line_local_up_offset
+						var cp = Geometry2D.get_closest_point_to_segment(content_position(event.position), from_pos, to_pos)
+						var d = cp.distance_to(content_position(event.position))
+						if d > connection.line.size.y * 2:
+							continue
+						if d < closest_d:
+							closest = i
+							closest_d = d
+					if closest >= 0:
+						hit_node = current_layer._connections[connection_list[closest].from][connection_list[closest].to].line
+						
+				if event.pressed:
+					if not (hit_node in _selection) and not event.shift_pressed:
+						# Click on empty space
+						clear_selection()
+					if hit_node:
+						# Click on node(can be a line)
+						_is_dragging_node = true
+						if hit_node is FlowChartLine:
+							current_layer.content_lines.move_child(hit_node, current_layer.content_lines.get_child_count()-1) # Raise selected line to top
+							if event.shift_pressed and can_gui_connect_node:
+								# Reconnection Start
+								for from in current_layer._connections.keys():
+									var from_connections = current_layer._connections[from]
+									for to in from_connections.keys():
+										var connection = from_connections[to]
+										if connection.line == hit_node:
+											_is_connecting = true
+											_is_dragging_node = false
+											_current_connection = connection
+											_on_node_reconnect_begin(current_layer, from, to)
+											break
+						if hit_node is FlowChartNode:
+							current_layer.content_nodes.move_child(hit_node, current_layer.content_nodes.get_child_count()-1) # Raise selected node to top
+							if event.shift_pressed and can_gui_connect_node:
+								# Connection start
+								if _request_connect_from(current_layer, hit_node.name):
+									_is_connecting = true
+									_is_dragging_node = false
+									var line = create_line_instance()
+									var connection = Connection.new(line, hit_node, null)
+									current_layer._connect_node(connection)
+									_current_connection = connection
+									_current_connection.line.join(_current_connection.get_from_pos(), content_position(event.position))
+							accept_event()
+						if _is_connecting:
+							clear_selection()
+						else:
+							if can_gui_select_node:
+								select(hit_node)
+					if not _is_dragging:
+						# Drag start
+						_is_dragging = true
+						for i in _selection.size():
+							var selected = _selection[i]
+							_drag_origins[i] = selected.position
+							selected.modulate.a = 1.0
+						_drag_start_pos = event.position
+						_drag_end_pos = event.position
+				else:
+					var was_connecting = _is_connecting
+					var was_dragging_node = _is_dragging_node
+					if _current_connection:
+						# Connection end
+						var from = _current_connection.from_node.name
+						var to = hit_node.name if hit_node else null
+						if hit_node is FlowChartNode and _request_connect_to(current_layer, to) and from != to:
+							# Connection success
+							var line
+							if _current_connection.to_node:
+								# Reconnection
+								line = disconnect_node(current_layer, from, _current_connection.to_node.name)
+								_current_connection.to_node = hit_node
+								_on_node_reconnect_end(current_layer, from, to)
+								connect_node(current_layer, from, to, line)
+							else:
+								# New Connection
+								current_layer.content_lines.remove_child(_current_connection.line)
+								line = _current_connection.line
+								_current_connection.to_node = hit_node
+								connect_node(current_layer, from, to, line)
+						else:
+							# Connection failed
+							if _current_connection.to_node:
+								# Reconnection
+								_current_connection.join()
+								_on_node_reconnect_failed(current_layer, from, name)
+							else:
+								# New Connection
+								_current_connection.line.queue_free()
+								_on_node_connect_failed(current_layer, from)
+						_is_connecting = false
+						_current_connection = null
+						accept_event()
+
+					if _is_dragging:
+						# Drag end
+						_is_dragging = false
+						_is_dragging_node = false
+						if not (was_connecting or was_dragging_node) and can_gui_select_node:
+							var selection_box_rect = get_selection_box_rect()
+							# Select node
+							for node in current_layer.content_nodes.get_children():
+								var rect = get_transform() * (content.get_transform() * (node.get_rect()))
+								if selection_box_rect.intersects(rect):
+									if node is FlowChartNode:
+										select(node)
+							# Select line
+							var connection_list = get_connection_list()
+							for i in connection_list.size():
+								var connection = current_layer._connections[connection_list[i].from][connection_list[i].to]
+								# Line's offset along its down-vector
+								var line_local_up_offset = connection.line.position - connection.line.get_transform() * (Vector2.UP * connection.offset)
+								var from_pos = content.get_transform() * (connection.get_from_pos() + line_local_up_offset)
+								var to_pos = content.get_transform() * (connection.get_to_pos() + line_local_up_offset)
+								if CohenSutherland.line_intersect_rectangle(from_pos, to_pos, selection_box_rect):
+									select(connection.line)
+						if was_dragging_node:
+							# Update _drag_origins with new position after dragged
+							for i in _selection.size():
+								var selected = _selection[i]
+								_drag_origins[i] = selected.position
+								selected.modulate.a = 1.0
+						_drag_start_pos = _drag_end_pos
+						queue_redraw()
+
+# Get selection box rect
+func get_selection_box_rect():
+	var pos = Vector2(min(_drag_start_pos.x, _drag_end_pos.x), min(_drag_start_pos.y, _drag_end_pos.y))
+	var size = (_drag_end_pos - _drag_start_pos).abs()
+	return Rect2(pos, size)
+
+# Get required scroll rect base on content
+func get_scroll_rect(layer=current_layer, force_scroll_margin=null):
+	var _scroll_margin = scroll_margin
+	if force_scroll_margin!=null:
+		_scroll_margin = force_scroll_margin
+	return layer.get_scroll_rect(_scroll_margin)
+
+func add_layer_to(target):
+	var layer = create_layer_instance()
+	target.add_child(layer)
+	return layer
+
+func get_layer(np):
+	return content.get_node_or_null(NodePath(np))
+
+func select_layer_at(i):
+	select_layer(content.get_child(i))
+
+func select_layer(layer):
+	var prev_layer = current_layer
+	_on_layer_deselected(prev_layer)
+	current_layer = layer
+	_on_layer_selected(layer)
+
+# Add node
+func add_node(layer, node):
+	layer.add_node(node)
+	_on_node_added(layer, node)
+
+# Remove node
+func remove_node(layer, node_name):
+	var node = layer.content_nodes.get_node_or_null(NodePath(node_name))
+	if node:
+		deselect(node) # Must deselct before remove to make sure _drag_origins synced with _selections
+		layer.remove_node(node)
+		_on_node_removed(layer, node_name)
+
+# Called after connection established
+func _connect_node(line, from_pos, to_pos):
+	pass
+
+# Called after connection broken
+func _disconnect_node(line):
+	if line in _selection:
+		deselect(line)
+
+func create_layer_instance():
+	var layer = Control.new()
+	layer.set_script(FlowChartLayer)
+	return layer
+
+# Return new line instance to use, called when connecting node
+func create_line_instance():
+	return FlowChartLineScene.instantiate()
+
+# Rename node
+func rename_node(layer, old, new):
+	layer.rename_node(old, new)
+
+# Connect two nodes with a line
+func connect_node(layer, from, to, line=null):
+	if not line:
+		line = create_line_instance()
+	line.name = "%s>%s" % [from, to] # "From>To"
+	layer.connect_node(line, from, to, interconnection_offset)
+	_on_node_connected(layer, from, to)
+	emit_signal("connection", from, to, line)
+
+# Break a connection between two node
+func disconnect_node(layer, from, to):
+	var line = layer.disconnect_node(from, to)
+	deselect(line) # Since line is selectable as well
+	_on_node_disconnected(layer, from, to)
+	emit_signal("disconnection", from, to)
+	return line
+
+# Clear all connections
+func clear_connections(layer=current_layer):
+	layer.clear_connections()
+
+# Select a node(can be a line)
+func select(node):
+	if node in _selection:
+		return
+
+	_selection.append(node)
+	node.selected = true
+	_drag_origins.append(node.position)
+	emit_signal("node_selected", node)
+
+# Deselect a node
+func deselect(node):
+	_selection.erase(node)
+	if is_instance_valid(node):
+		node.selected = false
+	_drag_origins.pop_back()
+	emit_signal("node_deselected", node)
+
+# Clear all selection
+func clear_selection():
+	for node in _selection.duplicate(): # duplicate _selection array as deselect() edit array
+		if not node:
+			continue
+		deselect(node)
+	_selection.clear()
+
+# Duplicate given nodes in editor
+func duplicate_nodes(layer, nodes):
+	clear_selection()
+	var new_nodes = []
+	for i in nodes.size():
+		var node = nodes[i]
+		if not (node is FlowChartNode):
+			continue
+		var new_node = node.duplicate(DUPLICATE_SIGNALS + DUPLICATE_SCRIPTS)
+		var offset = content_position(get_local_mouse_position()) - content_position(_drag_end_pos)
+		new_node.position = new_node.position + offset
+		new_nodes.append(new_node)
+		add_node(layer, new_node)
+		select(new_node)
+	# Duplicate connection within selection
+	for i in nodes.size():
+		var from_node = nodes[i]
+		for connection_pair in get_connection_list():
+			if from_node.name == connection_pair.from:
+				for j in nodes.size():
+					var to_node = nodes[j]
+					if to_node.name == connection_pair.to:
+						connect_node(layer, new_nodes[i].name, new_nodes[j].name)
+	_on_duplicated(layer, nodes, new_nodes)
+
+# Called after layer selected(current_layer changed)
+func _on_layer_selected(layer):
+	pass
+
+func _on_layer_deselected(layer):
+	pass
+
+# Called after a node added
+func _on_node_added(layer, node):
+	pass
+
+# Called after a node removed
+func _on_node_removed(layer, node):
+	pass
+
+# Called when a node dragged
+func _on_node_dragged(layer, node, dragged):
+	pass
+
+# Called when connection established between two nodes
+func _on_node_connected(layer, from, to):
+	pass
+
+# Called when connection broken
+func _on_node_disconnected(layer, from, to):
+	pass
+
+func _on_node_connect_failed(layer, from):
+	pass
+
+func _on_node_reconnect_begin(layer, from, to):
+	pass
+
+func _on_node_reconnect_end(layer, from, to):
+	pass
+
+func _on_node_reconnect_failed(layer, from, to):
+	pass
+
+func _request_connect_from(layer, from):
+	return true
+
+func _request_connect_to(layer, to):
+	return true
+
+# Called when nodes duplicated
+func _on_duplicated(layer, old_nodes, new_nodes):
+	pass
+
+# Convert position in FlowChart space to content(takes translation/scale of content into account)
+func content_position(pos):
+	return (pos - content.position - content.pivot_offset * (Vector2.ONE - content.scale)) * 1.0/content.scale
+
+# Return array of dictionary of connection as such [{"from1": "to1"}, {"from2": "to2"}]
+func get_connection_list(layer=current_layer):
+	return layer.get_connection_list()

addons/imjp94.yafsm/scenes/flowchart/FlowChartGrid.gd

@@ -0,0 +1,64 @@
+extends Control
+
+var flowchart
+	
+func _ready():
+    flowchart = get_parent().get_parent()
+    queue_redraw()
+
+# Original Draw in FlowChart.gd inspired by:
+# https://github.com/godotengine/godot/blob/6019dab0b45e1291e556e6d9e01b625b5076cc3c/scene/gui/graph_edit.cpp#L442
+func _draw():
+
+    self.position = flowchart.position
+    # Extents of the grid.
+    self.size = flowchart.size*100  # good with min_zoom = 0.5 e max_zoom = 2.0
+
+    var zoom = flowchart.zoom
+    var snap = flowchart.snap
+
+    # Origin of the grid. 
+    var offset = -Vector2(1, 1)*10000  # good with min_zoom = 0.5 e max_zoom = 2.0
+    
+    var corrected_size = size/zoom
+
+    var from = (offset / snap).floor()
+    var l = (corrected_size / snap).floor() + Vector2(1, 1)
+
+    var grid_minor = flowchart.grid_minor_color
+    var grid_major = flowchart.grid_major_color
+
+    var multi_line_vector_array: PackedVector2Array = PackedVector2Array()
+    var multi_line_color_array: PackedColorArray  = PackedColorArray ()
+
+    # for (int i = from.x; i < from.x + len.x; i++) {
+    for i in range(from.x, from.x + l.x):
+        var color
+
+        if (int(abs(i)) % 10 == 0):
+            color = grid_major
+        else:
+            color = grid_minor
+
+        var base_ofs = i * snap
+
+        multi_line_vector_array.append(Vector2(base_ofs, offset.y))
+        multi_line_vector_array.append(Vector2(base_ofs, corrected_size.y))
+        multi_line_color_array.append(color)
+
+    # for (int i = from.y; i < from.y + len.y; i++) {
+    for i in range(from.y, from.y + l.y):
+        var color
+
+        if (int(abs(i)) % 10 == 0):
+            color = grid_major
+        else:
+            color = grid_minor
+
+        var base_ofs = i * snap
+
+        multi_line_vector_array.append(Vector2(offset.x, base_ofs))
+        multi_line_vector_array.append(Vector2(corrected_size.x, base_ofs))
+        multi_line_color_array.append(color)
+
+    draw_multiline_colors(multi_line_vector_array, multi_line_color_array, -1)

addons/imjp94.yafsm/scenes/flowchart/FlowChartLayer.gd

@@ -0,0 +1,157 @@
+@tool
+extends Control
+const FlowChartNode = preload("res://addons/imjp94.yafsm/scenes/flowchart/FlowChartNode.gd")
+
+var content_lines = Control.new() # Node that hold all flowchart lines
+var content_nodes = Control.new() # Node that hold all flowchart nodes
+
+var _connections = {}
+
+func _init():
+	
+	name = "FlowChartLayer"
+	mouse_filter = MOUSE_FILTER_IGNORE
+
+	content_lines.name = "content_lines"
+	content_lines.mouse_filter = MOUSE_FILTER_IGNORE
+	add_child(content_lines)
+	move_child(content_lines, 0) # Make sure content_lines always behind nodes
+
+	content_nodes.name = "content_nodes"
+	content_nodes.mouse_filter = MOUSE_FILTER_IGNORE
+	add_child(content_nodes)
+
+func hide_content():
+	content_nodes.hide()
+	content_lines.hide()
+
+func show_content():
+	content_nodes.show()
+	content_lines.show()
+
+# Get required scroll rect base on content
+func get_scroll_rect(scroll_margin=0):
+	var rect = Rect2()
+	for child in content_nodes.get_children():
+		# Every child is a state/statemachine node
+		var child_rect = child.get_rect()
+		rect = rect.merge(child_rect)
+	return rect.grow(scroll_margin)
+
+# Add node
+func add_node(node):
+	content_nodes.add_child(node)
+
+# Remove node
+func remove_node(node):
+	if node:
+		content_nodes.remove_child(node)
+
+# Called after connection established
+func _connect_node(connection):
+	content_lines.add_child(connection.line)
+	connection.join()
+
+# Called after connection broken
+func _disconnect_node(connection):
+	content_lines.remove_child(connection.line)
+	return connection.line
+
+# Rename node
+func rename_node(old, new):
+	for from in _connections.keys():
+		if from == old: # Connection from
+			var from_connections = _connections[from]
+			_connections.erase(old)
+			_connections[new] = from_connections
+		else: # Connection to
+			for to in _connections[from].keys():
+				if to == old:
+					var from_connection = _connections[from]
+					var value = from_connection[old]
+					from_connection.erase(old)
+					from_connection[new] = value
+
+# Connect two nodes with a line
+func connect_node(line, from, to, interconnection_offset=0):
+	if from == to:
+		return # Connect to self
+	var connections_from = _connections.get(from)
+	if connections_from:
+		if to in connections_from:
+			return # Connection existed
+	var connection = Connection.new(line, content_nodes.get_node(NodePath(from)), content_nodes.get_node(NodePath(to)))
+	if connections_from == null:
+		connections_from = {}
+		_connections[from] = connections_from
+	connections_from[to] = connection
+	_connect_node(connection)
+
+	# Check if connection in both ways
+	connections_from = _connections.get(to)
+	if connections_from:
+		var inv_connection = connections_from.get(from)
+		if inv_connection:
+			connection.offset = interconnection_offset
+			inv_connection.offset = interconnection_offset
+			connection.join()
+			inv_connection.join()
+
+# Break a connection between two node
+func disconnect_node(from, to):
+	var connections_from = _connections.get(from)
+	var connection = connections_from.get(to)
+	if connection == null:
+		return
+
+	_disconnect_node(connection)
+	if connections_from.size() == 1:
+		_connections.erase(from)
+	else:
+		connections_from.erase(to)
+
+	connections_from = _connections.get(to)
+	if connections_from:
+		var inv_connection = connections_from.get(from)
+		if inv_connection:
+			inv_connection.offset = 0
+			inv_connection.join()
+	return connection.line
+
+# Clear all selection
+func clear_connections():
+	for connections_from in _connections.values():
+		for connection in connections_from.values():
+			connection.line.queue_free()
+	_connections.clear()
+			
+# Return array of dictionary of connection as such [{"from1": "to1"}, {"from2": "to2"}]
+func get_connection_list():
+	var connection_list = []
+	for connections_from in _connections.values():
+		for connection in connections_from.values():
+			connection_list.append({"from": connection.from_node.name, "to": connection.to_node.name})
+	return connection_list
+
+class Connection:
+	var line # Control node that draw line
+	var from_node
+	var to_node
+	var offset = 0 # line's y offset to make space for two interconnecting lines
+
+	func _init(p_line, p_from_node, p_to_node):
+		line = p_line
+		from_node = p_from_node
+		to_node = p_to_node
+
+	# Update line position
+	func join():
+		line.join(get_from_pos(), get_to_pos(), offset, [from_node.get_rect() if from_node else Rect2(), to_node.get_rect() if to_node else Rect2()])
+
+	# Return start position of line
+	func get_from_pos():
+		return from_node.position + from_node.size / 2
+
+	# Return destination position of line
+	func get_to_pos():
+		return to_node.position + to_node.size / 2 if to_node else line.position

addons/imjp94.yafsm/scenes/flowchart/FlowChartLine.gd

@@ -0,0 +1,91 @@
+@tool
+extends Container
+# Custom style normal, focus, arrow
+
+var selected: = false:
+	set = set_selected
+
+
+func _init():
+	
+	focus_mode = FOCUS_CLICK
+	mouse_filter = MOUSE_FILTER_IGNORE
+
+func _draw():
+	pivot_at_line_start()
+	var from = Vector2.ZERO
+	from.y += size.y / 2.0
+	var to = size
+	to.y -= size.y / 2.0
+	var arrow = get_theme_icon("arrow", "FlowChartLine")
+	var tint = Color.WHITE
+	if selected:
+		tint = get_theme_stylebox("focus", "FlowChartLine").shadow_color
+		draw_style_box(get_theme_stylebox("focus", "FlowChartLine"), Rect2(Vector2.ZERO, size))
+	else:
+		draw_style_box(get_theme_stylebox("normal", "FlowChartLine"), Rect2(Vector2.ZERO, size))
+	
+	
+	draw_texture(arrow, Vector2.ZERO - arrow.get_size() / 2 + size / 2, tint)
+
+func _get_minimum_size():
+	return Vector2(0, 5)
+
+func pivot_at_line_start():
+	pivot_offset.x = 0
+	pivot_offset.y = size.y / 2.0
+
+func join(from, to, offset=Vector2.ZERO, clip_rects=[]):
+	# Offset along perpendicular direction
+	var perp_dir = from.direction_to(to).rotated(deg_to_rad(90.0)).normalized()
+	from -= perp_dir * offset
+	to -= perp_dir * offset
+
+	var dist = from.distance_to(to)
+	var dir = from.direction_to(to)
+	var center = from + dir * dist / 2
+
+	# Clip line with provided Rect2 array
+	var clipped = [[from, to]]
+	var line_from = from
+	var line_to = to
+	for clip_rect in clip_rects:
+		if clipped.size() == 0:
+			break
+		
+		line_from = clipped[0][0]
+		line_to = clipped[0][1]
+		clipped = Geometry2D.clip_polyline_with_polygon(
+			[line_from, line_to], 
+			[clip_rect.position, Vector2(clip_rect.position.x, clip_rect.end.y), 
+				clip_rect.end, Vector2(clip_rect.end.x, clip_rect.position.y)]
+		)
+
+	if clipped.size() > 0:
+		from = clipped[0][0]
+		to = clipped[0][1]
+	else: # Line is totally overlapped
+		from = center
+		to = center + dir * 0.1
+
+	# Extends line by 2px to minimise ugly seam	
+	from -= dir * 2.0
+	to += dir * 2.0
+
+	size.x = to.distance_to(from)
+	# size.y equals to the thickness of line
+	position = from
+	position.y -= size.y / 2.0
+	rotation = Vector2.RIGHT.angle_to(dir)
+	pivot_at_line_start()
+
+func set_selected(v):
+	if selected != v:
+		selected = v
+		queue_redraw()
+
+func get_from_pos():
+	return get_transform() * (position)
+
+func get_to_pos():
+	return get_transform() * (position + size)

addons/imjp94.yafsm/scenes/flowchart/FlowChartNode.gd

@@ -0,0 +1,33 @@
+@tool
+extends Container
+# Custom style normal, focus
+
+var selected: = false:
+	set = set_selected
+
+
+func _init():
+	
+	focus_mode = FOCUS_NONE # Let FlowChart has the focus to handle gui_input
+	mouse_filter = MOUSE_FILTER_PASS
+
+func _draw():
+	if selected:
+		draw_style_box(get_theme_stylebox("focus", "FlowChartNode"), Rect2(Vector2.ZERO, size))
+	else:
+		draw_style_box(get_theme_stylebox("normal", "FlowChartNode"), Rect2(Vector2.ZERO, size))
+
+func _notification(what):
+	match what:
+		NOTIFICATION_SORT_CHILDREN:
+			for child in get_children():
+				if child is Control:
+					fit_child_in_rect(child, Rect2(Vector2.ZERO, size))
+
+func _get_minimum_size():
+	return Vector2(50, 50)
+
+func set_selected(v):
+	if selected != v:
+		selected = v
+		queue_redraw()

addons/imjp94.yafsm/scenes/flowchart/FlowChartNode.tscn

@@ -0,0 +1,34 @@
+[gd_scene load_steps=5 format=3 uid="uid://bar1eob74t82f"]
+
+[ext_resource type="Script" path="res://addons/imjp94.yafsm/scenes/flowchart/FlowChartNode.gd" id="1"]
+
+[sub_resource type="StyleBoxFlat" id="1"]
+bg_color = Color(0.164706, 0.164706, 0.164706, 1)
+border_width_left = 1
+border_width_top = 1
+border_width_right = 1
+border_width_bottom = 1
+border_color = Color(0.901961, 0.756863, 0.243137, 1)
+corner_radius_top_left = 4
+corner_radius_top_right = 4
+corner_radius_bottom_right = 4
+corner_radius_bottom_left = 4
+
+[sub_resource type="StyleBoxFlat" id="2"]
+bg_color = Color(0.164706, 0.164706, 0.164706, 1)
+border_width_left = 1
+border_width_top = 1
+border_width_right = 1
+border_width_bottom = 1
+corner_radius_top_left = 4
+corner_radius_top_right = 4
+corner_radius_bottom_right = 4
+corner_radius_bottom_left = 4
+
+[sub_resource type="Theme" id="3"]
+FlowChartNode/styles/focus = SubResource("1")
+FlowChartNode/styles/normal = SubResource("2")
+
+[node name="FlowChartNode" type="Container"]
+theme = SubResource("3")
+script = ExtResource("1")

addons/imjp94.yafsm/scenes/state_nodes/StateInspector.gd

@@ -0,0 +1,11 @@
+extends EditorInspectorPlugin
+
+const State = preload("res://addons/imjp94.yafsm/src/states/State.gd")
+
+func _can_handle(object):
+	return object is State
+
+func _parse_property(object, type, path, hint, hint_text, usage, wide) -> bool:
+	return false
+	# Hide all property
+	return true

addons/imjp94.yafsm/scenes/state_nodes/StateNode.gd

@@ -0,0 +1,82 @@
+@tool
+extends "res://addons/imjp94.yafsm/scenes/flowchart/FlowChartNode.gd"
+const State = preload("../../src/states/State.gd")
+const StateMachine = preload("../../src/states/StateMachine.gd")
+
+signal name_edit_entered(new_name) # Emits when focused exit or Enter pressed
+
+@onready var name_edit = $MarginContainer/NameEdit
+
+var undo_redo
+
+var state:
+	set = set_state
+
+
+func _init():
+	super._init()
+	
+	set_state(State.new())
+
+func _ready():
+	name_edit.focus_exited.connect(_on_NameEdit_focus_exited)
+	name_edit.text_submitted.connect(_on_NameEdit_text_submitted)
+	set_process_input(false) # _input only required when name_edit enabled to check mouse click outside
+
+func _draw():
+	if state is StateMachine:
+		if selected:
+			draw_style_box(get_theme_stylebox("nested_focus", "StateNode"), Rect2(Vector2.ZERO, size))
+		else:
+			draw_style_box(get_theme_stylebox("nested_normal", "StateNode"), Rect2(Vector2.ZERO, size))
+	else:
+		super._draw()
+
+func _input(event):
+	if event is InputEventMouseButton:
+		if event.pressed:
+			# Detect click outside rect
+			if get_viewport().gui_get_focus_owner() == name_edit:
+				var local_event = make_input_local(event)
+				if not name_edit.get_rect().has_point(local_event.position):
+					name_edit.release_focus()
+
+func enable_name_edit(v):
+	if v:
+		set_process_input(true)
+		name_edit.editable = true
+		name_edit.selecting_enabled = true
+		name_edit.mouse_filter = MOUSE_FILTER_PASS
+		mouse_default_cursor_shape = CURSOR_IBEAM
+		name_edit.grab_focus()
+	else:
+		set_process_input(false)
+		name_edit.editable = false
+		name_edit.selecting_enabled = false
+		name_edit.mouse_filter = MOUSE_FILTER_IGNORE
+		mouse_default_cursor_shape = CURSOR_ARROW
+		name_edit.release_focus()
+
+func _on_state_name_changed(new_name):
+	name_edit.text = new_name
+	size.x = 0 # Force reset horizontal size
+
+func _on_state_changed(new_state):
+	if state:
+		state.name_changed.connect(_on_state_name_changed)
+		if name_edit:
+			name_edit.text = state.name
+
+func _on_NameEdit_focus_exited():
+	enable_name_edit(false)
+	name_edit.deselect()
+	emit_signal("name_edit_entered", name_edit.text)
+
+func _on_NameEdit_text_submitted(new_text):
+	enable_name_edit(false)
+	emit_signal("name_edit_entered", new_text)
+
+func set_state(s):
+	if state != s:
+		state = s
+		_on_state_changed(s)

addons/imjp94.yafsm/scenes/state_nodes/StateNode.tscn

@@ -0,0 +1,79 @@
+[gd_scene load_steps=8 format=3 uid="uid://l3mqbqjwjkc3"]
+
+[ext_resource type="Script" path="res://addons/imjp94.yafsm/scenes/state_nodes/StateNode.gd" id="2"]
+[ext_resource type="SystemFont" uid="uid://dmcxm8gxsonbq" path="res://addons/imjp94.yafsm/assets/fonts/sans_serif.tres" id="2_352m3"]
+
+[sub_resource type="StyleBoxFlat" id="1"]
+bg_color = Color(0.164706, 0.164706, 0.164706, 1)
+border_width_left = 1
+border_width_top = 1
+border_width_right = 1
+border_width_bottom = 1
+border_color = Color(0.44, 0.73, 0.98, 1)
+corner_radius_top_left = 4
+corner_radius_top_right = 4
+corner_radius_bottom_right = 4
+corner_radius_bottom_left = 4
+
+[sub_resource type="StyleBoxFlat" id="2"]
+bg_color = Color(0.164706, 0.164706, 0.164706, 1)
+border_width_left = 1
+border_width_top = 1
+border_width_right = 1
+border_width_bottom = 1
+corner_radius_top_left = 4
+corner_radius_top_right = 4
+corner_radius_bottom_right = 4
+corner_radius_bottom_left = 4
+corner_detail = 2
+
+[sub_resource type="StyleBoxFlat" id="3"]
+bg_color = Color(0.164706, 0.164706, 0.164706, 1)
+border_width_left = 3
+border_width_top = 3
+border_width_right = 3
+border_width_bottom = 3
+border_color = Color(0.960784, 0.772549, 0.333333, 1)
+shadow_size = 2
+
+[sub_resource type="StyleBoxFlat" id="4"]
+bg_color = Color(0.164706, 0.164706, 0.164706, 1)
+border_width_left = 3
+border_width_top = 3
+border_width_right = 3
+border_width_bottom = 3
+shadow_size = 2
+
+[sub_resource type="Theme" id="5"]
+FlowChartNode/styles/focus = SubResource("1")
+FlowChartNode/styles/normal = SubResource("2")
+StateNode/styles/nested_focus = SubResource("3")
+StateNode/styles/nested_normal = SubResource("4")
+
+[node name="StateNode" type="HBoxContainer"]
+grow_horizontal = 2
+grow_vertical = 2
+theme = SubResource("5")
+script = ExtResource("2")
+
+[node name="MarginContainer" type="MarginContainer" parent="."]
+layout_mode = 2
+mouse_filter = 2
+theme_override_constants/margin_left = 5
+theme_override_constants/margin_top = 5
+theme_override_constants/margin_right = 5
+theme_override_constants/margin_bottom = 5
+
+[node name="NameEdit" type="LineEdit" parent="MarginContainer"]
+layout_mode = 2
+size_flags_horizontal = 4
+size_flags_vertical = 4
+mouse_filter = 2
+mouse_default_cursor_shape = 0
+theme_override_fonts/font = ExtResource("2_352m3")
+text = "State"
+alignment = 1
+editable = false
+expand_to_text_length = true
+selecting_enabled = false
+caret_blink = true

addons/imjp94.yafsm/scenes/transition_editors/TransitionEditor.gd

@@ -0,0 +1,185 @@
+@tool
+extends VBoxContainer
+const Utils = preload("../../scripts/Utils.gd")
+const ConditionEditor = preload("../condition_editors/ConditionEditor.tscn")
+const BoolConditionEditor = preload("../condition_editors/BoolConditionEditor.tscn")
+const IntegerConditionEditor = preload("../condition_editors/IntegerConditionEditor.tscn")
+const FloatConditionEditor = preload("../condition_editors/FloatConditionEditor.tscn")
+const StringConditionEditor = preload("../condition_editors/StringConditionEditor.tscn")
+
+@onready var header = $HeaderContainer/Header
+@onready var title = $HeaderContainer/Header/Title
+@onready var title_icon = $HeaderContainer/Header/Title/Icon
+@onready var from = $HeaderContainer/Header/Title/From
+@onready var to = $HeaderContainer/Header/Title/To
+@onready var condition_count_icon = $HeaderContainer/Header/ConditionCount/Icon
+@onready var condition_count_label = $HeaderContainer/Header/ConditionCount/Label
+@onready var priority_icon = $HeaderContainer/Header/Priority/Icon
+@onready var priority_spinbox = $HeaderContainer/Header/Priority/SpinBox
+@onready var add = $HeaderContainer/Header/HBoxContainer/Add
+@onready var add_popup_menu = $HeaderContainer/Header/HBoxContainer/Add/PopupMenu
+@onready var content_container = $MarginContainer
+@onready var condition_list = $MarginContainer/Conditions
+
+var undo_redo
+
+var transition:
+	set = set_transition
+
+var _to_free
+
+
+func _init():
+	_to_free = []
+
+func _ready():
+	header.gui_input.connect(_on_header_gui_input)
+	priority_spinbox.value_changed.connect(_on_priority_spinbox_value_changed)
+	add.pressed.connect(_on_add_pressed)
+	add_popup_menu.index_pressed.connect(_on_add_popup_menu_index_pressed)
+
+	condition_count_icon.texture = get_theme_icon("MirrorX", "EditorIcons")
+	priority_icon.texture = get_theme_icon("AnimationTrackGroup", "EditorIcons")
+
+func _exit_tree():
+	free_node_from_undo_redo() # Managed by EditorInspector
+
+func _on_header_gui_input(event):
+	if event is InputEventMouseButton:
+		if event.button_index == MOUSE_BUTTON_LEFT and event.pressed:
+			toggle_conditions()
+
+func _on_priority_spinbox_value_changed(val: int) -> void:
+	set_priority(val)
+
+func _on_add_pressed():
+	Utils.popup_on_target(add_popup_menu, add)
+
+func _on_add_popup_menu_index_pressed(index):
+	## Handle condition name duplication (4.x changed how duplicates are
+	## automatically handled and gave a random index instead of a progressive one)
+	var default_new_condition_name = "Param"
+	var condition_dup_index = 0
+	var new_name = default_new_condition_name
+	for condition_editor in condition_list.get_children():
+		var condition_name = condition_editor.condition.name
+		if (condition_name == new_name):
+			condition_dup_index += 1
+			new_name = "%s%s" % [default_new_condition_name, condition_dup_index]
+	var condition
+	match index:
+		0: # Trigger
+			condition = Condition.new(new_name)
+		1: # Boolean
+			condition = BooleanCondition.new(new_name)
+		2: # Integer
+			condition = IntegerCondition.new(new_name)
+		3: # Float
+			condition = FloatCondition.new(new_name)
+		4: # String
+			condition = StringCondition.new(new_name)
+		_:
+			push_error("Unexpected index(%d) from PopupMenu" % index)
+	var editor = create_condition_editor(condition)
+	add_condition_editor_action(editor, condition)
+
+func _on_ConditionEditorRemove_pressed(editor):
+	remove_condition_editor_action(editor)
+
+func _on_transition_changed(new_transition):
+	if not new_transition:
+		return
+
+	for condition in transition.conditions.values():
+		var editor = create_condition_editor(condition)
+		add_condition_editor(editor, condition)
+	update_title()
+	update_condition_count()
+	update_priority_spinbox_value()
+
+func _on_condition_editor_added(editor):
+	editor.undo_redo = undo_redo
+	if not editor.remove.pressed.is_connected(_on_ConditionEditorRemove_pressed):
+		editor.remove.pressed.connect(_on_ConditionEditorRemove_pressed.bind(editor))
+	transition.add_condition(editor.condition)
+	update_condition_count()
+
+func add_condition_editor(editor, condition):
+	condition_list.add_child(editor)
+	editor.condition = condition # Must be assigned after enter tree, as assignment would trigger ui code
+	_on_condition_editor_added(editor)
+
+func remove_condition_editor(editor):
+	transition.remove_condition(editor.condition.name)
+	condition_list.remove_child(editor)
+	_to_free.append(editor) # Freeing immediately after removal will break undo/redo
+	update_condition_count()
+
+func update_title():
+	from.text = transition.from
+	to.text = transition.to
+
+func update_condition_count():
+	var count = transition.conditions.size()
+	condition_count_label.text = str(count)
+	if count == 0:
+		hide_conditions()
+	else:
+		show_conditions()
+
+func update_priority_spinbox_value():
+	priority_spinbox.value = transition.priority
+	priority_spinbox.apply()
+	
+func set_priority(value):
+	transition.priority = value
+
+func show_conditions():
+	content_container.visible = true
+
+func hide_conditions():
+	content_container.visible = false
+
+func toggle_conditions():
+	content_container.visible = !content_container.visible
+
+func create_condition_editor(condition):
+	var editor
+	if condition is BooleanCondition:
+		editor = BoolConditionEditor.instantiate()
+	elif condition is IntegerCondition:
+		editor = IntegerConditionEditor.instantiate()
+	elif condition is FloatCondition:
+		editor = FloatConditionEditor.instantiate()
+	elif condition is StringCondition:
+		editor = StringConditionEditor.instantiate()
+	else:
+		editor = ConditionEditor.instantiate()
+	return editor
+
+func add_condition_editor_action(editor, condition):
+	undo_redo.create_action("Add Transition Condition")
+	undo_redo.add_do_method(self, "add_condition_editor", editor, condition)
+	undo_redo.add_undo_method(self, "remove_condition_editor", editor)
+	undo_redo.commit_action()
+
+func remove_condition_editor_action(editor):
+	undo_redo.create_action("Remove Transition Condition")
+	undo_redo.add_do_method(self, "remove_condition_editor", editor)
+	undo_redo.add_undo_method(self, "add_condition_editor", editor, editor.condition)
+	undo_redo.commit_action()
+
+func set_transition(t):
+	if transition != t:
+		transition = t
+		_on_transition_changed(t)
+
+# Free nodes cached in UndoRedo stack
+func free_node_from_undo_redo():
+	for node in _to_free:
+		if is_instance_valid(node):
+			var history_id = undo_redo.get_object_history_id(node)
+			undo_redo.get_history_undo_redo(history_id).clear_history(false) # TODO: Should be handled by plugin.gd (Temporary solution as only TransitionEditor support undo/redo)
+			node.queue_free()
+
+	_to_free.clear()

addons/imjp94.yafsm/scenes/transition_editors/TransitionEditor.tscn

@@ -0,0 +1,133 @@
+[gd_scene load_steps=7 format=3 uid="uid://dw0ecw2wdeosi"]
+
+[ext_resource type="Texture2D" uid="uid://dg8cmn5ubq6r5" path="res://addons/imjp94.yafsm/assets/icons/add-white-18dp.svg" id="1"]
+[ext_resource type="Script" path="res://addons/imjp94.yafsm/scenes/transition_editors/TransitionEditor.gd" id="3"]
+
+[sub_resource type="Gradient" id="Gradient_hw7k8"]
+offsets = PackedFloat32Array(1)
+colors = PackedColorArray(1, 1, 1, 1)
+
+[sub_resource type="GradientTexture2D" id="GradientTexture2D_ipxab"]
+gradient = SubResource("Gradient_hw7k8")
+width = 18
+height = 18
+
+[sub_resource type="Image" id="Image_o35y7"]
+data = {
+"data": PackedByteArray(255, 255, 255, 0, 255, 255, 255, 0, 255, 128, 128, 4, 255, 128, 128, 4, 255, 128, 128, 4, 255, 128, 128, 4, 255, 128, 128, 4, 255, 128, 128, 4, 255, 128, 128, 4, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 255, 255, 0, 255, 93, 93, 131, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 255, 255, 0, 255, 93, 93, 255, 255, 93, 93, 131, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 255, 255, 0, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 131, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 255, 255, 0, 255, 93, 93, 252, 255, 93, 93, 252, 255, 93, 93, 252, 255, 94, 94, 127, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 128, 128, 4, 255, 128, 128, 4, 255, 128, 128, 4, 255, 128, 128, 4, 255, 128, 128, 4, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 93, 93, 231, 255, 93, 93, 55, 255, 97, 97, 58, 255, 93, 93, 233, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 231, 255, 94, 94, 54, 255, 94, 94, 57, 255, 93, 93, 233, 255, 93, 93, 255, 255, 93, 93, 255, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 97, 97, 42, 255, 255, 255, 0, 255, 255, 255, 0, 255, 97, 97, 42, 255, 93, 93, 233, 255, 93, 93, 232, 255, 93, 93, 41, 255, 255, 255, 0, 255, 255, 255, 0, 255, 97, 97, 42, 255, 93, 93, 233, 255, 93, 93, 232, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 96, 96, 45, 255, 97, 97, 42, 255, 255, 255, 0, 255, 97, 97, 42, 255, 97, 97, 42, 255, 255, 255, 0, 255, 98, 98, 47, 255, 97, 97, 42, 255, 255, 255, 0, 255, 97, 97, 42, 255, 97, 97, 42, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 96, 96, 45, 255, 93, 93, 235, 255, 93, 93, 233, 255, 97, 97, 42, 255, 255, 255, 0, 255, 255, 255, 0, 255, 94, 94, 46, 255, 93, 93, 236, 255, 93, 93, 233, 255, 97, 97, 42, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 93, 93, 235, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 233, 255, 95, 95, 59, 255, 96, 96, 61, 255, 93, 93, 235, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 233, 255, 95, 95, 59, 255, 96, 96, 61, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 93, 93, 255, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 93, 93, 252, 255, 93, 93, 252, 255, 93, 93, 252, 255, 93, 93, 252, 255, 93, 93, 252, 255, 93, 93, 252, 255, 93, 93, 252, 255, 93, 93, 252, 255, 93, 93, 252, 255, 93, 93, 252, 255, 93, 93, 252, 255, 93, 93, 252, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0, 255, 255, 255, 0),
+"format": "RGBA8",
+"height": 16,
+"mipmaps": false,
+"width": 16
+}
+
+[sub_resource type="ImageTexture" id="ImageTexture_v636r"]
+image = SubResource("Image_o35y7")
+
+[node name="TransitionEditor" type="VBoxContainer"]
+script = ExtResource("3")
+
+[node name="HeaderContainer" type="MarginContainer" parent="."]
+layout_mode = 2
+
+[node name="Panel" type="Panel" parent="HeaderContainer"]
+layout_mode = 2
+
+[node name="Header" type="HBoxContainer" parent="HeaderContainer"]
+layout_mode = 2
+
+[node name="Title" type="HBoxContainer" parent="HeaderContainer/Header"]
+layout_mode = 2
+tooltip_text = "Next State"
+
+[node name="From" type="Label" parent="HeaderContainer/Header/Title"]
+layout_mode = 2
+size_flags_horizontal = 3
+text = "From"
+
+[node name="Icon" type="TextureRect" parent="HeaderContainer/Header/Title"]
+texture_filter = 1
+layout_mode = 2
+texture = SubResource("GradientTexture2D_ipxab")
+expand_mode = 3
+stretch_mode = 3
+
+[node name="To" type="Label" parent="HeaderContainer/Header/Title"]
+layout_mode = 2
+size_flags_horizontal = 3
+text = "To"
+
+[node name="VSeparator" type="VSeparator" parent="HeaderContainer/Header"]
+layout_mode = 2
+
+[node name="ConditionCount" type="HBoxContainer" parent="HeaderContainer/Header"]
+layout_mode = 2
+tooltip_text = "Number of Conditions"
+
+[node name="Icon" type="TextureRect" parent="HeaderContainer/Header/ConditionCount"]
+texture_filter = 1
+layout_mode = 2
+texture = SubResource("ImageTexture_v636r")
+expand_mode = 3
+stretch_mode = 3
+
+[node name="Label" type="Label" parent="HeaderContainer/Header/ConditionCount"]
+layout_mode = 2
+text = "No."
+
+[node name="VSeparator2" type="VSeparator" parent="HeaderContainer/Header"]
+layout_mode = 2
+
+[node name="Priority" type="HBoxContainer" parent="HeaderContainer/Header"]
+layout_mode = 2
+tooltip_text = "Priority"
+
+[node name="Icon" type="TextureRect" parent="HeaderContainer/Header/Priority"]
+texture_filter = 1
+layout_mode = 2
+texture = SubResource("ImageTexture_v636r")
+expand_mode = 3
+stretch_mode = 3
+
+[node name="SpinBox" type="SpinBox" parent="HeaderContainer/Header/Priority"]
+layout_mode = 2
+max_value = 10.0
+rounded = true
+allow_greater = true
+
+[node name="VSeparator3" type="VSeparator" parent="HeaderContainer/Header"]
+layout_mode = 2
+
+[node name="HBoxContainer" type="HBoxContainer" parent="HeaderContainer/Header"]
+layout_mode = 2
+size_flags_horizontal = 10
+
+[node name="Add" type="Button" parent="HeaderContainer/Header/HBoxContainer"]
+layout_mode = 2
+tooltip_text = "Add Condition"
+icon = ExtResource("1")
+flat = true
+
+[node name="PopupMenu" type="PopupMenu" parent="HeaderContainer/Header/HBoxContainer/Add"]
+item_count = 5
+item_0/text = "Trigger"
+item_0/id = 0
+item_1/text = "Boolean"
+item_1/id = 1
+item_2/text = "Integer"
+item_2/id = 2
+item_3/text = "Float"
+item_3/id = 3
+item_4/text = "String"
+item_4/id = 4
+
+[node name="MarginContainer" type="MarginContainer" parent="."]
+layout_mode = 2
+
+[node name="Panel" type="Panel" parent="MarginContainer"]
+layout_mode = 2
+size_flags_horizontal = 3
+size_flags_vertical = 3
+
+[node name="Conditions" type="VBoxContainer" parent="MarginContainer"]
+layout_mode = 2

addons/imjp94.yafsm/scenes/transition_editors/TransitionInspector.gd

@@ -0,0 +1,33 @@
+@tool
+extends EditorInspectorPlugin
+const Transition = preload("res://addons/imjp94.yafsm/src/transitions/Transition.gd")
+
+const TransitionEditor = preload("res://addons/imjp94.yafsm/scenes/transition_editors/TransitionEditor.tscn")
+
+var undo_redo
+
+var transition_icon
+
+func _can_handle(object):
+	return object is Transition
+
+func _parse_property(object, type, path, hint, hint_text, usage, wide) -> bool:
+	match path:
+		"from":
+			return true
+		"to":
+			return true
+		"conditions":
+			var transition_editor = TransitionEditor.instantiate() # Will be freed by editor
+			transition_editor.undo_redo = undo_redo
+			add_custom_control(transition_editor)
+			transition_editor.ready.connect(_on_transition_editor_tree_entered.bind(transition_editor, object))
+			return true
+		"priority":
+			return true
+	return false
+
+func _on_transition_editor_tree_entered(editor, transition):
+	editor.transition = transition
+	if transition_icon:
+		editor.title_icon.texture = transition_icon

addons/imjp94.yafsm/scenes/transition_editors/TransitionLine.gd

@@ -0,0 +1,112 @@
+@tool
+extends "res://addons/imjp94.yafsm/scenes/flowchart/FlowChartLine.gd"
+const Transition = preload("../../src/transitions/Transition.gd")
+const ValueCondition = preload("../../src/conditions/ValueCondition.gd")
+
+const hi_res_font: Font = preload("res://addons/imjp94.yafsm/assets/fonts/sans_serif.tres")
+
+@export var upright_angle_range: = 5.0
+
+@onready var label_margin = $MarginContainer
+@onready var vbox = $MarginContainer/VBoxContainer
+
+var undo_redo
+
+var transition:
+	set = set_transition
+var template = "{condition_name} {condition_comparation} {condition_value}"
+
+var _template_var = {}
+
+func _init():
+	super._init()
+	
+	set_transition(Transition.new())
+
+func _draw():
+	super._draw()
+
+	var abs_rotation = abs(rotation)
+	var is_flip = abs_rotation > deg_to_rad(90.0)
+	var is_upright = (abs_rotation > (deg_to_rad(90.0) - deg_to_rad(upright_angle_range))) and (abs_rotation < (deg_to_rad(90.0) + deg_to_rad(upright_angle_range)))
+
+	if is_upright:
+		var x_offset = label_margin.size.x / 2
+		var y_offset = -label_margin.size.y
+		label_margin.position = Vector2((size.x - x_offset) / 2, 0)
+	else:
+		var x_offset = label_margin.size.x
+		var y_offset = -label_margin.size.y
+		if is_flip:
+			label_margin.rotation = deg_to_rad(180)
+			label_margin.position = Vector2((size.x + x_offset) / 2, 0)
+		else:
+			label_margin.rotation = deg_to_rad(0)
+			label_margin.position = Vector2((size.x - x_offset) / 2, y_offset)
+
+# Update overlay text
+func update_label():
+	if transition:
+		var template_var = {"condition_name": "", "condition_comparation": "", "condition_value": null}
+		for label in vbox.get_children():
+			if not (str(label.name) in transition.conditions.keys()):  # Names of nodes are now of type StringName, not simple strings!
+				vbox.remove_child(label)
+				label.queue_free()
+		for condition in transition.conditions.values():
+			var label = vbox.get_node_or_null(NodePath(condition.name))
+			if not label:
+				label = Label.new()
+				label.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
+				label.add_theme_font_override("font", hi_res_font)
+				label.name = condition.name
+				vbox.add_child(label)
+			if "value" in condition:
+				template_var["condition_name"] = condition.name
+				template_var["condition_comparation"] = ValueCondition.COMPARATION_SYMBOLS[condition.comparation]
+				template_var["condition_value"] = condition.get_value_string()
+				label.text = template.format(template_var)
+				var override_template_var = _template_var.get(condition.name)
+				if override_template_var:
+					label.text = label.text.format(override_template_var)
+			else:
+				label.text = condition.name
+	queue_redraw()
+
+func _on_transition_changed(new_transition):
+	if not is_inside_tree():
+		return
+
+	if new_transition:
+		new_transition.condition_added.connect(_on_transition_condition_added)
+		new_transition.condition_removed.connect(_on_transition_condition_removed)
+		for condition in new_transition.conditions.values():
+			condition.name_changed.connect(_on_condition_name_changed)
+			condition.display_string_changed.connect(_on_condition_display_string_changed)
+	update_label()
+
+func _on_transition_condition_added(condition):
+	condition.name_changed.connect(_on_condition_name_changed)
+	condition.display_string_changed.connect(_on_condition_display_string_changed)
+	update_label()
+
+func _on_transition_condition_removed(condition):
+	condition.name_changed.disconnect(_on_condition_name_changed)
+	condition.display_string_changed.disconnect(_on_condition_display_string_changed)
+	update_label()
+
+func _on_condition_name_changed(from, to):
+	var label = vbox.get_node_or_null(NodePath(from))
+	if label:
+		label.name = to
+	update_label()
+
+func _on_condition_display_string_changed(display_string):
+	update_label()
+
+func set_transition(t):
+	if transition != t:
+		if transition:
+			if transition.condition_added.is_connected(_on_transition_condition_added):
+				transition.condition_added.disconnect(_on_transition_condition_added)
+		transition = t
+		_on_transition_changed(transition)

addons/imjp94.yafsm/scenes/transition_editors/TransitionLine.tscn

@@ -0,0 +1,26 @@
+[gd_scene load_steps=4 format=3 uid="uid://cwb2nrjai7fao"]
+
+[ext_resource type="PackedScene" uid="uid://creoglbeckyhs" path="res://addons/imjp94.yafsm/scenes/flowchart/FlowChartLine.tscn" id="1"]
+[ext_resource type="Script" path="res://addons/imjp94.yafsm/scenes/transition_editors/TransitionLine.gd" id="2"]
+[ext_resource type="SystemFont" uid="uid://dmcxm8gxsonbq" path="res://addons/imjp94.yafsm/assets/fonts/sans_serif.tres" id="3_y6xyv"]
+
+[node name="TransitionLine" instance=ExtResource("1")]
+script = ExtResource("2")
+upright_angle_range = 0.0
+
+[node name="MarginContainer" type="MarginContainer" parent="." index="0"]
+layout_mode = 2
+mouse_filter = 2
+
+[node name="Label" type="Label" parent="MarginContainer" index="0"]
+visible = false
+layout_mode = 2
+size_flags_horizontal = 6
+size_flags_vertical = 6
+theme_override_fonts/font = ExtResource("3_y6xyv")
+text = "Transition"
+
+[node name="VBoxContainer" type="VBoxContainer" parent="MarginContainer" index="1"]
+layout_mode = 2
+size_flags_horizontal = 4
+size_flags_vertical = 4