Refactor rhythm action architecture

scenes/ui/energy_bar.gd

@@ -0,0 +1,58 @@
+class_name EnergyBar
+extends HBoxContainer
+
+@export var segment_count := 10
+
+var segments: Array[Panel] = []
+
+
+func _ready() -> void:
+	_build_segments()
+	_event_bus().connect("player_energy_changed", refresh)
+
+
+func refresh(current: float, maximum: float) -> void:
+	if segments.is_empty():
+		_build_segments()
+	var filled := clampi(int(round(current)), 0, min(segment_count, int(maximum)))
+	for index: int in range(segments.size()):
+		segments[index].modulate = Color(1.0, 1.0, 1.0, 1.0 if index < filled else 0.35)
+
+
+func _build_segments() -> void:
+	if not segments.is_empty():
+		return
+	for child: Node in get_children():
+		var panel := child as Panel
+		if panel != null:
+			segments.append(panel)
+	if segments.size() >= segment_count:
+		return
+	for index: int in range(segments.size(), segment_count):
+		var panel := Panel.new()
+		panel.custom_minimum_size = Vector2(23, 16)
+		panel.modulate = Color(1.0, 1.0, 1.0, 0.35)
+		panel.add_theme_stylebox_override("panel", _make_segment_style())
+		add_child(panel)
+		segments.append(panel)
+
+
+func _make_segment_style() -> StyleBoxFlat:
+	var style := StyleBoxFlat.new()
+	style.bg_color = Color(0.18, 0.66, 0.95, 1.0)
+	style.border_width_left = 1
+	style.border_width_top = 1
+	style.border_width_right = 1
+	style.border_width_bottom = 1
+	style.border_color = Color(0.66, 0.92, 1.0, 0.9)
+	return style
+
+
+func _event_bus() -> Node:
+	var root := get_tree().root
+	var bus := root.get_node_or_null("EventBus")
+	if bus == null:
+		bus = load("res://autoload/event_bus.gd").new()
+		bus.name = "EventBus"
+		root.add_child(bus)
+	return bus