blocks: Add groups option block extension

Several blocks work with node groups. Rather than having the user enter
the group, offer the current groups as options. This is trickier than
expected since Godot offers no API to get the current groups. Finding
them involves 2 parts:

* Get scene local groups by calling get_groups() on each node in the
  scene.

* Get project global groups (starting in 4.3) by getting the
  `global_group` values in the project settings.

Monitoring for changes to the global groups is possible by listening for
project settings changes. Monitoring for local group changes is not
possible since the only events that occur are internal to Godot and not
available in GDScript.

https://phabricator.endlessm.com/T35647

Author: dbnicholson

addons/block_code/blocks/communication/add_node_to_group.tres

@@ -1,6 +1,13 @@
-[gd_resource type="Resource" load_steps=2 format=3 uid="uid://bpvefei72nh3a"]
+[gd_resource type="Resource" load_steps=5 format=3 uid="uid://bpvefei72nh3a"]
 
 [ext_resource type="Script" path="res://addons/block_code/code_generation/block_definition.gd" id="1_5qal7"]
+[ext_resource type="Script" path="res://addons/block_code/code_generation/option_data.gd" id="1_auf06"]
+[ext_resource type="Script" path="res://addons/block_code/blocks/communication/groups.gd" id="1_p83c7"]
+
+[sub_resource type="Resource" id="Resource_sus0f"]
+script = ExtResource("1_auf06")
+selected = 0
+items = []
 
 [resource]
 script = ExtResource("1_5qal7")
@@ -10,8 +17,11 @@ description = "Add the node into the group"
 category = "Communication | Groups"
 type = 2
 variant_type = 0
-display_template = "add {node: OBJECT} to group {group: STRING}"
-code_template = "{node}.add_to_group({group})"
-defaults = {}
+display_template = "add {node: OBJECT} to group {group: NIL}"
+code_template = "{node}.add_to_group(\\\"{group}\\\")"
+defaults = {
+"group": SubResource("Resource_sus0f")
+}
 signal_name = ""
 scope = ""
+extension_script = ExtResource("1_p83c7")

addons/block_code/blocks/communication/add_to_group.tres

@@ -1,6 +1,13 @@
-[gd_resource type="Resource" load_steps=2 format=3 uid="uid://bvrmau8atjx1x"]
+[gd_resource type="Resource" load_steps=5 format=3 uid="uid://bvrmau8atjx1x"]
 
+[ext_resource type="Script" path="res://addons/block_code/code_generation/option_data.gd" id="1_aom4j"]
 [ext_resource type="Script" path="res://addons/block_code/code_generation/block_definition.gd" id="1_bcm71"]
+[ext_resource type="Script" path="res://addons/block_code/blocks/communication/groups.gd" id="2_42ixf"]
+
+[sub_resource type="Resource" id="Resource_fk0wa"]
+script = ExtResource("1_aom4j")
+selected = 0
+items = []
 
 [resource]
 script = ExtResource("1_bcm71")
@@ -10,8 +17,11 @@ description = "Add this node into the group"
 category = "Communication | Groups"
 type = 2
 variant_type = 0
-display_template = "add to group {group: STRING}"
-code_template = "add_to_group({group})"
-defaults = {}
+display_template = "add to group {group: NIL}"
+code_template = "add_to_group(\\\"{group}\\\")"
+defaults = {
+"group": SubResource("Resource_fk0wa")
+}
 signal_name = ""
 scope = ""
+extension_script = ExtResource("2_42ixf")

addons/block_code/blocks/communication/call_method_group.tres

@@ -1,6 +1,13 @@
-[gd_resource type="Resource" load_steps=2 format=3 uid="uid://c15vtdfihdxb8"]
+[gd_resource type="Resource" load_steps=5 format=3 uid="uid://c15vtdfihdxb8"]
 
+[ext_resource type="Script" path="res://addons/block_code/code_generation/option_data.gd" id="1_3nuts"]
 [ext_resource type="Script" path="res://addons/block_code/code_generation/block_definition.gd" id="1_mlm68"]
+[ext_resource type="Script" path="res://addons/block_code/blocks/communication/groups.gd" id="1_of577"]
+
+[sub_resource type="Resource" id="Resource_f4ctg"]
+script = ExtResource("1_3nuts")
+selected = 0
+items = []
 
 [resource]
 script = ExtResource("1_mlm68")
@@ -10,8 +17,11 @@ description = "Calls the method/function on each member of the given group"
 category = "Communication | Methods"
 type = 2
 variant_type = 0
-display_template = "call method {method_name: STRING} in group {group: STRING}"
-code_template = "get_tree().call_group({group}, {method_name})"
-defaults = {}
+display_template = "call method {method_name: STRING} in group {group: NIL}"
+code_template = "get_tree().call_group(\\\"{group\\\"}, {method_name})"
+defaults = {
+"group": SubResource("Resource_f4ctg")
+}
 signal_name = ""
 scope = ""
+extension_script = ExtResource("1_of577")

addons/block_code/blocks/communication/groups.gd

@@ -0,0 +1,71 @@
+@tool
+## Common BlockExtension for scene group options.
+extends BlockExtension
+
+const OptionData = preload("res://addons/block_code/code_generation/option_data.gd")
+const Util = preload("res://addons/block_code/ui/util.gd")
+
+
+# Global groups are just project settings in the global_group group.
+# ProjectSettings doesn't offer an API to get the project groups or to get all
+# settings. Fortunately, settings are simply implemented as properties on the
+# ProjectSettings object.
+static func _add_global_groups(groups: Dictionary):
+	for prop in ProjectSettings.get_property_list():
+		var name: String = prop["name"]
+		var parts := name.split("/", false, 1)
+		if parts[0] == "global_group":
+			groups[parts[1]] = null
+
+
+# Add all the groups in a node and its children, ignoring internal _ prefixed
+# groups.
+static func _add_node_groups(groups: Dictionary, node: Node):
+	for group in node.get_groups():
+		if not group.begins_with("_"):
+			groups[String(group)] = null
+
+	for child in node.get_children():
+		_add_node_groups(groups, child)
+
+
+func _get_edited_scene_groups() -> Array[String]:
+	var groups: Dictionary
+	_add_global_groups(groups)
+
+	var root := context_node.get_tree().edited_scene_root
+	_add_node_groups(groups, root)
+
+	var sorted_groups: Array[String]
+	sorted_groups.assign(groups.keys())
+	sorted_groups.sort()
+	return sorted_groups
+
+
+func _init():
+	# FIXME: Only global group changes are monitored. Scene local groups should
+	# also be monitored, but godot does not have any reasonable API to do that.
+	ProjectSettings.settings_changed.connect(_on_project_settings_changed)
+
+
+func _context_node_changed():
+	# If the context node changed, the scene local groups need to be updated.
+	changed.emit()
+
+
+func get_defaults() -> Dictionary:
+	if not context_node:
+		return {}
+
+	# The default groups are only needed in the editor.
+	if not Util.node_is_part_of_edited_scene(context_node):
+		return {}
+
+	var groups: Array[String] = _get_edited_scene_groups()
+	return {"group": OptionData.new(groups)}
+
+
+func _on_project_settings_changed():
+	# FIXME: The global groups should be cached and compared so that the
+	# defaults are only changed when the global groups actually change.
+	changed.emit()

addons/block_code/blocks/communication/is_in_group.tres

@@ -1,6 +1,13 @@
-[gd_resource type="Resource" load_steps=2 format=3 uid="uid://q4cnstftvsiu"]
+[gd_resource type="Resource" load_steps=5 format=3 uid="uid://q4cnstftvsiu"]
 
+[ext_resource type="Script" path="res://addons/block_code/code_generation/option_data.gd" id="1_cla3i"]
 [ext_resource type="Script" path="res://addons/block_code/code_generation/block_definition.gd" id="1_tjyq5"]
+[ext_resource type="Script" path="res://addons/block_code/blocks/communication/groups.gd" id="2_o165d"]
+
+[sub_resource type="Resource" id="Resource_d0v0d"]
+script = ExtResource("1_cla3i")
+selected = 0
+items = []
 
 [resource]
 script = ExtResource("1_tjyq5")
@@ -10,8 +17,11 @@ description = "Is this node in the group"
 category = "Communication | Groups"
 type = 3
 variant_type = 1
-display_template = "is in group {group: STRING}"
-code_template = "is_in_group({group})"
-defaults = {}
+display_template = "is in group {group: NIL}"
+code_template = "is_in_group(\\\"{group}\\\")"
+defaults = {
+"group": SubResource("Resource_d0v0d")
+}
 signal_name = ""
 scope = ""
+extension_script = ExtResource("2_o165d")

addons/block_code/blocks/communication/is_node_in_group.tres

@@ -1,6 +1,13 @@
-[gd_resource type="Resource" load_steps=2 format=3 uid="uid://bbtdxeey74x67"]
+[gd_resource type="Resource" load_steps=5 format=3 uid="uid://bbtdxeey74x67"]
 
 [ext_resource type="Script" path="res://addons/block_code/code_generation/block_definition.gd" id="1_5krrs"]
+[ext_resource type="Script" path="res://addons/block_code/blocks/communication/groups.gd" id="1_r4prw"]
+[ext_resource type="Script" path="res://addons/block_code/code_generation/option_data.gd" id="1_y4j0k"]
+
+[sub_resource type="Resource" id="Resource_o38ym"]
+script = ExtResource("1_y4j0k")
+selected = 0
+items = []
 
 [resource]
 script = ExtResource("1_5krrs")
@@ -10,8 +17,11 @@ description = "Is the node in the group"
 category = "Communication | Groups"
 type = 3
 variant_type = 1
-display_template = "{node: OBJECT} is in group {group: STRING}"
-code_template = "{node}.is_in_group({group})"
-defaults = {}
+display_template = "{node: OBJECT} is in group {group: NIL}"
+code_template = "{node}.is_in_group(\\\"{group}\\\")"
+defaults = {
+"group": SubResource("Resource_o38ym")
+}
 signal_name = ""
 scope = ""
+extension_script = ExtResource("1_r4prw")

addons/block_code/blocks/communication/remove_from_group.tres

@@ -1,6 +1,13 @@
-[gd_resource type="Resource" load_steps=2 format=3 uid="uid://dgenw5wyqorvq"]
+[gd_resource type="Resource" load_steps=5 format=3 uid="uid://dgenw5wyqorvq"]
 
 [ext_resource type="Script" path="res://addons/block_code/code_generation/block_definition.gd" id="1_cdwef"]
+[ext_resource type="Script" path="res://addons/block_code/blocks/communication/groups.gd" id="1_i50fw"]
+[ext_resource type="Script" path="res://addons/block_code/code_generation/option_data.gd" id="1_mnxp7"]
+
+[sub_resource type="Resource" id="Resource_45b71"]
+script = ExtResource("1_mnxp7")
+selected = 0
+items = []
 
 [resource]
 script = ExtResource("1_cdwef")
@@ -10,8 +17,11 @@ description = "Remove this node from the group"
 category = "Communication | Groups"
 type = 2
 variant_type = 0
-display_template = "remove from group {group: STRING}"
-code_template = "remove_from_group({group})"
-defaults = {}
+display_template = "remove from group {group: NIL}"
+code_template = "remove_from_group(\\\"{group}\\\")"
+defaults = {
+"group": SubResource("Resource_45b71")
+}
 signal_name = ""
 scope = ""
+extension_script = ExtResource("1_i50fw")

addons/block_code/blocks/communication/remove_node_from_group.tres

@@ -1,7 +1,14 @@
-[gd_resource type="Resource" load_steps=2 format=3 uid="uid://b2dwk77hnri8y"]
+[gd_resource type="Resource" load_steps=5 format=3 uid="uid://b2dwk77hnri8y"]
 
+[ext_resource type="Script" path="res://addons/block_code/code_generation/option_data.gd" id="1_clwhe"]
+[ext_resource type="Script" path="res://addons/block_code/blocks/communication/groups.gd" id="1_h3lhb"]
 [ext_resource type="Script" path="res://addons/block_code/code_generation/block_definition.gd" id="1_pec24"]
 
+[sub_resource type="Resource" id="Resource_03rge"]
+script = ExtResource("1_clwhe")
+selected = 0
+items = []
+
 [resource]
 script = ExtResource("1_pec24")
 name = &"remove_node_from_group"
@@ -10,8 +17,11 @@ description = "Remove the node from the group"
 category = "Communication | Groups"
 type = 2
 variant_type = 0
-display_template = "remove {node: OBJECT} from group {group: STRING}"
-code_template = "{node}.remove_from_group({group})"
-defaults = {}
+display_template = "remove {node: OBJECT} from group {group: NIL}"
+code_template = "{node}.remove_from_group(\\\"{group}\\\")"
+defaults = {
+"group": SubResource("Resource_03rge")
+}
 signal_name = ""
 scope = ""
+extension_script = ExtResource("1_h3lhb")