ParameterInput: Detect click & drag gestures

addons/block_code/ui/blocks/block/block.gd

@@ -78,12 +78,18 @@ func _update_template_editor():
 	template_editor.parameter_defaults = _get_parameter_defaults()
 	if not template_editor.modified.is_connected(_on_template_editor_modified):
 		template_editor.modified.connect(_on_template_editor_modified)
+	if not template_editor.drag_started.is_connected(_on_template_editor_drag_started):
+		template_editor.drag_started.connect(_on_template_editor_drag_started)
 
 
 func _on_template_editor_modified():
 	modified.emit()
 
 
+func _on_template_editor_drag_started():
+	_drag_started()
+
+
 func _get_format_string() -> String:
 	if not definition:
 		return ""

addons/block_code/ui/blocks/utilities/parameter_input/parameter_input.gd

@@ -1,6 +1,9 @@
 @tool
 extends MarginContainer
 
+signal drag_started
+
+const Constants = preload("res://addons/block_code/ui/constants.gd")
 const OptionData = preload("res://addons/block_code/code_generation/option_data.gd")
 const Types = preload("res://addons/block_code/types/types.gd")
 
@@ -16,6 +19,9 @@ signal modified
 
 var default_value: Variant
 
+var _drag_start: Vector2 = Vector2.INF
+var _is_dragging: bool = false
+
 @onready var _panel := %Panel
 @onready var snap_point := %SnapPoint
 @onready var _input_switcher := %InputSwitcher
@@ -283,3 +289,32 @@ func _on_option_input_item_selected(index):
 
 func _on_snap_point_snapped_block_changed(block):
 	_update_visible_input()
+
+
+func _input(event: InputEvent) -> void:
+	if snap_point.has_snapped_block():
+		return
+
+	if event is InputEventMouseButton:
+		var button_event: InputEventMouseButton = event as InputEventMouseButton
+
+		if button_event.button_index != MOUSE_BUTTON_LEFT:
+			return
+
+		if button_event.double_click:
+			# Double click event (with the mouse released) has both pressed=true
+			# and double_click=true, so ignore it as a special case.
+			pass
+		elif button_event.pressed and get_global_rect().has_point(button_event.global_position):
+			# Keep track of where the mouse click originated, but allow this
+			# event to propagate to other nodes.
+			_drag_start = event.global_position
+		else:
+			_drag_start = Vector2.INF
+	elif _drag_start != Vector2.INF and event is InputEventMouseMotion:
+		var motion_event: InputEventMouseMotion = event as InputEventMouseMotion
+
+		if not get_global_rect().has_point(event.global_position) and _drag_start.distance_to(event.global_position) > Constants.MINIMUM_DRAG_THRESHOLD:
+			get_viewport().set_input_as_handled()
+			drag_started.emit()
+			_drag_start = Vector2.INF

addons/block_code/ui/blocks/utilities/parameter_input/parameter_input.tscn

@@ -87,6 +87,7 @@ custom_minimum_size = Vector2(40, 0)
 layout_mode = 2
 tooltip_text = "Parameter"
 theme_override_styles/normal = SubResource("StyleBoxEmpty_fjquj")
+action_mode = 1
 fit_to_longest_item = false
 
 [node name="Vector2Input" type="MarginContainer" parent="InputSwitcher"]
@@ -171,6 +172,7 @@ theme_override_colors/font_focus_color = Color(0, 0, 0, 1)
 theme_override_colors/font_color = Color(0, 0, 0, 1)
 theme_override_styles/focus = SubResource("StyleBoxEmpty_e7f0k")
 theme_override_styles/normal = SubResource("StyleBoxEmpty_fjquj")
+action_mode = 1
 selected = 0
 item_count = 2
 popup/item_0/text = "False"

addons/block_code/ui/blocks/utilities/template_editor/template_editor.gd

@@ -2,6 +2,7 @@
 class_name TemplateEditor
 extends Container
 
+signal drag_started
 signal modified
 
 const BlockDefinition = preload("res://addons/block_code/code_generation/block_definition.gd")
@@ -113,6 +114,7 @@ func _append_input_parameter(parameter: Dictionary, id: int):
 	parameter_input.name = "ParameterInput%d" % id
 	parameter_input.placeholder = parameter["name"]
 	parameter_input.variant_type = parameter["type"]
+	parameter_input.drag_started.connect(_on_parameter_input_drag_started)
 
 	if default_value is OptionData:
 		var option_data := default_value as OptionData
@@ -136,3 +138,7 @@ func _append_output_parameter(parameter: Dictionary, id: int):
 	parameter_output.block = parent_block
 	parameter_output.parameter_name = parameter["name"]
 	_container.add_child(parameter_output)
+
+
+func _on_parameter_input_drag_started():
+	drag_started.emit()

addons/block_code/ui/constants.gd

@@ -9,6 +9,7 @@ const KNOB_Z = 5.0
 const CONTROL_MARGIN = 20.0
 const OUTLINE_WIDTH = 3.0
 const MINIMUM_SNAP_DISTANCE = 80.0
+const MINIMUM_DRAG_THRESHOLD = 25
 
 const FOCUS_BORDER_COLOR = Color(225, 242, 0)