[Editor] Replication plugin to configure MultiplayerSynchronizers.

Allows configuring the MultiplayerSynchornizer in a way similar to
AnimationPlayer.
Properties are added manually, edither as plain properties, or via the
NodePath format for child nodes' properties "path/to/node:property"
relative to the MultiplayerSynchronizer root path.

Nice things to add would be:
- Moving properties up/down in the list.
- Some form of keying, autmatic filling of the replication properity
  line edit.

3 files changed, 500 insertions, 0 deletions

diff --git a/editor/editor_node.cpp b/editor/editor_node.cpp
index 716d4a50c3..c9417ee57c 100644
--- a/editor/editor_node.cpp
+++ b/editor/editor_node.cpp
@@ -162,6 +162,7 @@
 #include "editor/plugins/path_3d_editor_plugin.h"
 #include "editor/plugins/physical_bone_3d_editor_plugin.h"
 #include "editor/plugins/polygon_2d_editor_plugin.h"
+#include "editor/plugins/replication_editor_plugin.h"
 #include "editor/plugins/resource_preloader_editor_plugin.h"
 #include "editor/plugins/root_motion_editor_plugin.h"
 #include "editor/plugins/script_editor_plugin.h"
@@ -7021,6 +7022,7 @@ EditorNode::EditorNode() {
 	add_editor_plugin(memnew(InputEventEditorPlugin(this)));
 	add_editor_plugin(memnew(SubViewportPreviewEditorPlugin(this)));
 	add_editor_plugin(memnew(TextControlEditorPlugin(this)));
+	add_editor_plugin(memnew(ReplicationEditorPlugin(this)));
 
 	for (int i = 0; i < EditorPlugins::get_plugin_count(); i++) {
 		add_editor_plugin(EditorPlugins::create(i, this));
diff --git a/editor/plugins/replication_editor_plugin.cpp b/editor/plugins/replication_editor_plugin.cpp
new file mode 100644
index 0000000000..93f4a853f3
--- /dev/null
+++ b/editor/plugins/replication_editor_plugin.cpp
@@ -0,0 +1,390 @@
+/*************************************************************************/
+/*  replication_editor_plugin.cpp                                        */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2022 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#include "replication_editor_plugin.h"
+
+#include "editor/editor_scale.h"
+#include "editor/inspector_dock.h"
+#include "scene/gui/dialogs.h"
+#include "scene/gui/tree.h"
+#include "scene/multiplayer/multiplayer_synchronizer.h"
+
+/// ReplicationEditor
+ReplicationEditor::ReplicationEditor(EditorNode *p_editor) {
+	editor = p_editor;
+	set_v_size_flags(SIZE_EXPAND_FILL);
+	set_custom_minimum_size(Size2(0, 200) * EDSCALE);
+
+	delete_dialog = memnew(ConfirmationDialog);
+	delete_dialog->connect("cancelled", callable_mp(this, &ReplicationEditor::_dialog_closed), varray(false));
+	delete_dialog->connect("confirmed", callable_mp(this, &ReplicationEditor::_dialog_closed), varray(true));
+	add_child(delete_dialog);
+
+	error_dialog = memnew(AcceptDialog);
+	error_dialog->get_ok_button()->set_text(TTR("Close"));
+	error_dialog->set_title(TTR("Error!"));
+	add_child(error_dialog);
+
+	VBoxContainer *vb = memnew(VBoxContainer);
+	vb->set_v_size_flags(SIZE_EXPAND_FILL);
+	add_child(vb);
+
+	HBoxContainer *hb = memnew(HBoxContainer);
+	vb->add_child(hb);
+	np_line_edit = memnew(LineEdit);
+	np_line_edit->set_placeholder(":property");
+	np_line_edit->set_h_size_flags(SIZE_EXPAND_FILL);
+	hb->add_child(np_line_edit);
+	add_button = memnew(Button);
+	add_button->connect("pressed", callable_mp(this, &ReplicationEditor::_add_pressed));
+	add_button->set_text(TTR("Add"));
+	hb->add_child(add_button);
+
+	tree = memnew(Tree);
+	tree->set_hide_root(true);
+	tree->set_columns(4);
+	tree->set_column_titles_visible(true);
+	tree->set_column_title(0, TTR("Properties"));
+	tree->set_column_expand(0, true);
+	tree->set_column_title(1, TTR("Spawn"));
+	tree->set_column_expand(1, false);
+	tree->set_column_custom_minimum_width(1, 100);
+	tree->set_column_title(2, TTR("Sync"));
+	tree->set_column_custom_minimum_width(2, 100);
+	tree->set_column_expand(2, false);
+	tree->set_column_expand(3, false);
+	tree->create_item();
+	tree->connect("button_pressed", callable_mp(this, &ReplicationEditor::_tree_button_pressed));
+	tree->connect("item_edited", callable_mp(this, &ReplicationEditor::_tree_item_edited));
+	tree->set_v_size_flags(SIZE_EXPAND_FILL);
+	vb->add_child(tree);
+}
+
+void ReplicationEditor::_bind_methods() {
+	ClassDB::bind_method(D_METHOD("_update_config"), &ReplicationEditor::_update_config);
+	ClassDB::bind_method(D_METHOD("_update_checked", "property", "column", "checked"), &ReplicationEditor::_update_checked);
+	ADD_SIGNAL(MethodInfo("keying_changed"));
+}
+
+void ReplicationEditor::_notification(int p_what) {
+	if (p_what == NOTIFICATION_ENTER_TREE || p_what == EditorSettings::NOTIFICATION_EDITOR_SETTINGS_CHANGED) {
+		add_theme_style_override("panel", editor->get_gui_base()->get_theme_stylebox(SNAME("panel"), SNAME("Panel")));
+	} else if (p_what == NOTIFICATION_VISIBILITY_CHANGED) {
+		update_keying();
+	}
+}
+
+void ReplicationEditor::_add_pressed() {
+	if (!current) {
+		error_dialog->set_text(TTR("Please select a MultiplayerSynchronizer first."));
+		error_dialog->popup_centered();
+		return;
+	}
+	if (current->get_root_path().is_empty()) {
+		error_dialog->set_text(TTR("The MultiplayerSynchronizer needs a root path."));
+		error_dialog->popup_centered();
+		return;
+	}
+	String np_text = np_line_edit->get_text();
+	if (np_text.find(":") == -1) {
+		np_text = ":" + np_text;
+	}
+	NodePath prop = NodePath(np_text);
+	if (prop.is_empty()) {
+		return;
+	}
+	UndoRedo *undo_redo = editor->get_undo_redo();
+	undo_redo->create_action(TTR("Add property"));
+	config = current->get_replication_config();
+	if (config.is_null()) {
+		config.instantiate();
+		current->set_replication_config(config);
+		undo_redo->add_do_method(current, "set_replication_config", config);
+		undo_redo->add_undo_method(current, "set_replication_config", Ref<SceneReplicationConfig>());
+		_update_config();
+	}
+	undo_redo->add_do_method(config.ptr(), "add_property", prop);
+	undo_redo->add_undo_method(config.ptr(), "remove_property", prop);
+	undo_redo->add_do_method(this, "_update_config");
+	undo_redo->add_undo_method(this, "_update_config");
+	undo_redo->commit_action();
+}
+
+void ReplicationEditor::_tree_item_edited() {
+	TreeItem *ti = tree->get_edited();
+	if (!ti || config.is_null()) {
+		return;
+	}
+	int column = tree->get_edited_column();
+	ERR_FAIL_COND(column < 1 || column > 2);
+	const NodePath prop = ti->get_metadata(0);
+	UndoRedo *undo_redo = editor->get_undo_redo();
+	bool value = ti->is_checked(column);
+	String method;
+	if (column == 1) {
+		undo_redo->create_action(TTR("Set spawn property"));
+		method = "property_set_spawn";
+	} else {
+		undo_redo->create_action(TTR("Set sync property"));
+		method = "property_set_sync";
+	}
+	undo_redo->add_do_method(config.ptr(), method, prop, value);
+	undo_redo->add_undo_method(config.ptr(), method, prop, !value);
+	undo_redo->add_do_method(this, "_update_checked", prop, column, value);
+	undo_redo->add_undo_method(this, "_update_checked", prop, column, !value);
+	undo_redo->commit_action();
+}
+
+void ReplicationEditor::_tree_button_pressed(Object *p_item, int p_column, int p_id) {
+	TreeItem *ti = Object::cast_to<TreeItem>(p_item);
+	if (!ti) {
+		return;
+	}
+	deleting = ti->get_metadata(0);
+	delete_dialog->set_text(TTR("Delete Property?") + "\n\"" + ti->get_text(0) + "\"");
+	delete_dialog->popup_centered();
+}
+
+void ReplicationEditor::_dialog_closed(bool p_confirmed) {
+	if (deleting.is_empty() || config.is_null()) {
+		return;
+	}
+	if (p_confirmed) {
+		const NodePath prop = deleting;
+		int idx = config->property_get_index(prop);
+		bool spawn = config->property_get_spawn(prop);
+		bool sync = config->property_get_sync(prop);
+		UndoRedo *undo_redo = editor->get_undo_redo();
+		undo_redo->create_action(TTR("Remove Property"));
+		undo_redo->add_do_method(config.ptr(), "remove_property", prop);
+		undo_redo->add_undo_method(config.ptr(), "add_property", prop, idx);
+		undo_redo->add_undo_method(config.ptr(), "property_set_spawn", prop, spawn);
+		undo_redo->add_undo_method(config.ptr(), "property_set_sync", prop, sync);
+		undo_redo->add_do_method(this, "_update_config");
+		undo_redo->add_undo_method(this, "_update_config");
+		undo_redo->commit_action();
+	}
+	deleting = NodePath();
+}
+
+void ReplicationEditor::_update_checked(const NodePath &p_prop, int p_column, bool p_checked) {
+	if (!tree->get_root()) {
+		return;
+	}
+	TreeItem *ti = tree->get_root()->get_first_child();
+	while (ti) {
+		if (ti->get_metadata(0).operator NodePath() == p_prop) {
+			ti->set_checked(p_column, p_checked);
+			return;
+		}
+		ti = ti->get_next();
+	}
+}
+
+void ReplicationEditor::update_keying() {
+	/// TODO make keying usable.
+#if 0
+	bool keying_enabled = false;
+	EditorHistory *editor_history = EditorNode::get_singleton()->get_editor_history();
+	if (is_visible_in_tree() && config.is_valid() && editor_history->get_path_size() > 0) {
+		Object *obj = ObjectDB::get_instance(editor_history->get_path_object(0));
+		keying_enabled = Object::cast_to<Node>(obj) != nullptr;
+	}
+
+	if (keying_enabled == keying) {
+		return;
+	}
+
+	keying = keying_enabled;
+	emit_signal(SNAME("keying_changed"));
+#endif
+}
+
+void ReplicationEditor::_update_config() {
+	deleting = NodePath();
+	tree->clear();
+	tree->create_item();
+	if (!config.is_valid()) {
+		update_keying();
+		return;
+	}
+	TypedArray<NodePath> props = config->get_properties();
+	for (int i = 0; i < props.size(); i++) {
+		const NodePath path = props[i];
+		_add_property(path, config->property_get_spawn(path), config->property_get_sync(path));
+	}
+	update_keying();
+}
+
+void ReplicationEditor::edit(MultiplayerSynchronizer *p_sync) {
+	if (current == p_sync) {
+		return;
+	}
+	current = p_sync;
+	if (current) {
+		config = current->get_replication_config();
+	} else {
+		config.unref();
+	}
+	_update_config();
+}
+
+Ref<Texture2D> ReplicationEditor::_get_class_icon(const Node *p_node) {
+	if (!p_node || !has_theme_icon(p_node->get_class(), "EditorIcons")) {
+		return get_theme_icon("ImportFail", "EditorIcons");
+	}
+	return get_theme_icon(p_node->get_class(), "EditorIcons");
+}
+
+void ReplicationEditor::_add_property(const NodePath &p_property, bool p_spawn, bool p_sync) {
+	String prop = String(p_property);
+	TreeItem *item = tree->create_item();
+	item->set_selectable(0, false);
+	item->set_selectable(1, false);
+	item->set_selectable(2, false);
+	item->set_selectable(3, false);
+	item->set_text(0, prop);
+	item->set_metadata(0, prop);
+	Node *root_node = current && !current->get_root_path().is_empty() ? current->get_node(current->get_root_path()) : nullptr;
+	Ref<Texture2D> icon = _get_class_icon(root_node);
+	if (root_node) {
+		String path = prop.substr(0, prop.find(":"));
+		String subpath = prop.substr(path.size());
+		Node *node = root_node->get_node_or_null(path);
+		if (!node) {
+			node = root_node;
+		}
+		item->set_text(0, String(node->get_name()) + ":" + subpath);
+		icon = _get_class_icon(node);
+	}
+	item->set_icon(0, icon);
+	item->add_button(3, get_theme_icon("Remove", "EditorIcons"));
+	item->set_text_alignment(1, HORIZONTAL_ALIGNMENT_CENTER);
+	item->set_cell_mode(1, TreeItem::CELL_MODE_CHECK);
+	item->set_checked(1, p_spawn);
+	item->set_editable(1, true);
+	item->set_text_alignment(2, HORIZONTAL_ALIGNMENT_CENTER);
+	item->set_cell_mode(2, TreeItem::CELL_MODE_CHECK);
+	item->set_checked(2, p_sync);
+	item->set_editable(2, true);
+}
+
+void ReplicationEditor::property_keyed(const String &p_property) {
+	ERR_FAIL_COND(!current || config.is_null());
+	Node *root = current->get_node(current->get_root_path());
+	ERR_FAIL_COND(!root);
+	EditorHistory *history = editor->get_editor_history();
+	ERR_FAIL_COND(history->get_path_size() == 0);
+	Node *node = Object::cast_to<Node>(ObjectDB::get_instance(history->get_path_object(0)));
+	ERR_FAIL_COND(!node);
+	if (node->is_class("MultiplayerSynchronizer")) {
+		error_dialog->set_text(TTR("Properties of 'MultiplayerSynchronizer' cannot be configured for replication."));
+		error_dialog->popup_centered();
+		return;
+	}
+	if (history->get_path_size() > 1 || p_property.get_slice_count(":") > 1) {
+		error_dialog->set_text(TTR("Subresources cannot yet be configured for replication."));
+		error_dialog->popup_centered();
+		return;
+	}
+
+	String path = root->get_path_to(node);
+	for (int i = 1; i < history->get_path_size(); i++) {
+		String prop = history->get_path_property(i);
+		ERR_FAIL_COND(prop == "");
+		path += ":" + prop;
+	}
+	path += ":" + p_property;
+
+	NodePath prop = path;
+	UndoRedo *undo_redo = editor->get_undo_redo();
+	undo_redo->create_action(TTR("Add property"));
+	undo_redo->add_do_method(config.ptr(), "add_property", prop);
+	undo_redo->add_undo_method(config.ptr(), "remove_property", prop);
+	undo_redo->add_do_method(this, "_update_config");
+	undo_redo->add_undo_method(this, "_update_config");
+	undo_redo->commit_action();
+}
+
+/// ReplicationEditorPlugin
+ReplicationEditorPlugin::ReplicationEditorPlugin(EditorNode *p_node) {
+	editor = p_node;
+	repl_editor = memnew(ReplicationEditor(editor));
+	editor->add_bottom_panel_item(TTR("Replication"), repl_editor);
+}
+
+ReplicationEditorPlugin::~ReplicationEditorPlugin() {
+}
+
+void ReplicationEditorPlugin::_keying_changed() {
+	// TODO make lock usable.
+	//InspectorDock::get_inspector_singleton()->set_keying(repl_editor->has_keying(), this);
+}
+
+void ReplicationEditorPlugin::_property_keyed(const String &p_keyed, const Variant &p_value, bool p_advance) {
+	if (!repl_editor->has_keying()) {
+		return;
+	}
+	repl_editor->property_keyed(p_keyed);
+}
+
+void ReplicationEditorPlugin::_notification(int p_what) {
+	if (p_what == NOTIFICATION_ENTER_TREE) {
+		//Node3DEditor::get_singleton()->connect("transform_key_request", callable_mp(this, &AnimationPlayerEditorPlugin::_transform_key_request));
+		InspectorDock::get_inspector_singleton()->connect("property_keyed", callable_mp(this, &ReplicationEditorPlugin::_property_keyed));
+		repl_editor->connect("keying_changed", callable_mp(this, &ReplicationEditorPlugin::_keying_changed));
+		// TODO make lock usable.
+		//InspectorDock::get_inspector_singleton()->connect("object_inspected", callable_mp(repl_editor, &ReplicationEditor::update_keying));
+		get_tree()->connect("node_removed", callable_mp(this, &ReplicationEditorPlugin::_node_removed));
+	}
+}
+
+void ReplicationEditorPlugin::_node_removed(Node *p_node) {
+	if (p_node && p_node == repl_editor->get_current()) {
+		repl_editor->edit(nullptr);
+		if (repl_editor->is_visible_in_tree()) {
+			editor->hide_bottom_panel();
+		}
+	}
+}
+
+void ReplicationEditorPlugin::edit(Object *p_object) {
+	repl_editor->edit(Object::cast_to<MultiplayerSynchronizer>(p_object));
+}
+
+bool ReplicationEditorPlugin::handles(Object *p_object) const {
+	return p_object->is_class("MultiplayerSynchronizer");
+}
+
+void ReplicationEditorPlugin::make_visible(bool p_visible) {
+	if (p_visible) {
+		editor->make_bottom_panel_item_visible(repl_editor);
+	}
+}
diff --git a/editor/plugins/replication_editor_plugin.h b/editor/plugins/replication_editor_plugin.h
new file mode 100644
index 0000000000..049eda99cc
--- /dev/null
+++ b/editor/plugins/replication_editor_plugin.h
@@ -0,0 +1,108 @@
+/*************************************************************************/
+/*  replication_editor_plugin.h                                          */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2022 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#ifndef REPLICATION_EDITOR_PLUGIN_H
+#define REPLICATION_EDITOR_PLUGIN_H
+
+#include "editor/editor_node.h"
+#include "editor/editor_plugin.h"
+#include "scene/resources/scene_replication_config.h"
+
+class ConfirmationDialog;
+class MultiplayerSynchronizer;
+class Tree;
+
+class ReplicationEditor : public VBoxContainer {
+	GDCLASS(ReplicationEditor, VBoxContainer);
+
+private:
+	EditorNode *editor;
+	MultiplayerSynchronizer *current = nullptr;
+
+	AcceptDialog *error_dialog = nullptr;
+	ConfirmationDialog *delete_dialog = nullptr;
+	Button *add_button = nullptr;
+	LineEdit *np_line_edit = nullptr;
+
+	Ref<SceneReplicationConfig> config;
+	NodePath deleting;
+	Tree *tree;
+	bool keying = false;
+
+	Ref<Texture2D> _get_class_icon(const Node *p_node);
+
+	void _add_pressed();
+	void _tree_item_edited();
+	void _tree_button_pressed(Object *p_item, int p_column, int p_id);
+	void _update_checked(const NodePath &p_prop, int p_column, bool p_checked);
+	void _update_config();
+	void _dialog_closed(bool p_confirmed);
+	void _add_property(const NodePath &p_property, bool p_spawn = true, bool p_sync = true);
+
+protected:
+	static void _bind_methods();
+
+	void _notification(int p_what);
+
+public:
+	void update_keying();
+	void edit(MultiplayerSynchronizer *p_object);
+	bool has_keying() const { return keying; }
+	MultiplayerSynchronizer *get_current() const { return current; }
+	void property_keyed(const String &p_property);
+
+	ReplicationEditor(EditorNode *p_node);
+	~ReplicationEditor() {}
+};
+
+class ReplicationEditorPlugin : public EditorPlugin {
+	GDCLASS(ReplicationEditorPlugin, EditorPlugin);
+
+private:
+	EditorNode *editor;
+	ReplicationEditor *repl_editor;
+
+	void _node_removed(Node *p_node);
+	void _keying_changed();
+	void _property_keyed(const String &p_keyed, const Variant &p_value, bool p_advance);
+
+protected:
+	void _notification(int p_what);
+
+public:
+	virtual void edit(Object *p_object) override;
+	virtual bool handles(Object *p_object) const override;
+	virtual void make_visible(bool p_visible) override;
+
+	ReplicationEditorPlugin(EditorNode *p_node);
+	~ReplicationEditorPlugin();
+};
+
+#endif // REPLICATION_EDITOR_PLUGIN_H