finish undo/redo rework

* "Undo(Redo) last brushstroke" -> "Undo(Redo)".
* Sync `_updateActionSensitivity` menu method with the new undo/redo behavior.
* Smooth button action is no longer destructive.
* Clean undone smooth transformations when doing a new smooth transformation.

elements.js

@@ -413,6 +413,9 @@ const _DrawingElement = new Lang.Class({
         this.transformations.push({ type: Transformations.SMOOTH, undoable: true,
                                     undo: () => this.points = oldPoints,
                                     redo: () => this.points = newPoints });
+        
+        if (this._undoneTransformations)
+            this._undoneTransformations = this._undoneTransformations.filter(transformation => transformation.type != Transformations.SMOOTH);
     },
     
     addPoint: function() {
@@ -636,6 +639,10 @@ const _DrawingElement = new Lang.Class({
         delete this._undoneTransformations;
     },
     
+    get canUndo() {
+        return this._undoneTransformations && this._undoneTransformations.length ? true : false;
+    },
+    
     // The figure rotation center before transformations (original).
     // this.textWidth is computed during Cairo building.
     _getOriginalCenter: function() {

locale/draw-on-your-screen.pot

@@ -10,7 +10,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: Draw On Your Screen\n"
 "Report-Msgid-Bugs-To: https://framagit.org/abakkk/DrawOnYourScreen/issues\n"
-"POT-Creation-Date: 2020-09-19 15:32+0200\n"
+"POT-Creation-Date: 2020-10-04 22:45+0200\n"
 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
 "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
 "Language-Team: LANGUAGE <LL@li.org>\n"
@@ -265,12 +265,6 @@ msgctxt "drawing-tool"
 msgid "Mirror"
 msgstr ""
 
-msgid "Undo"
-msgstr ""
-
-msgid "Redo"
-msgstr ""
-
 msgid "Erase"
 msgstr ""
 
@@ -586,7 +580,7 @@ msgstr ""
 msgid "Add images from the clipboard"
 msgstr ""
 
-msgid "Redo last brushstroke"
+msgid "Redo"
 msgstr ""
 
 msgid "Save drawing"
@@ -710,5 +704,5 @@ msgstr ""
 msgid "Square drawing area"
 msgstr ""
 
-msgid "Undo last brushstroke"
+msgid "Undo"
 msgstr ""

menu.js

@@ -230,12 +230,11 @@ var DrawingMenu = new Lang.Class({
         this.menu.removeAll();
         
         let groupItem = new PopupMenu.PopupBaseMenuItem({ reactive: false, can_focus: false, style_class: 'draw-on-your-screen-menu-group-item' });
-        this.undoButton = new ActionButton(_("Undo"), 'edit-undo-symbolic', this.area.undo.bind(this.area), this._updateActionSensitivity.bind(this));
+        this.undoButton = new ActionButton(getSummary('undo'), 'edit-undo-symbolic', this.area.undo.bind(this.area), this._updateActionSensitivity.bind(this));
-        this.redoButton = new ActionButton(_("Redo"), 'edit-redo-symbolic', this.area.redo.bind(this.area), this._updateActionSensitivity.bind(this));
+        this.redoButton = new ActionButton(getSummary('redo'), 'edit-redo-symbolic', this.area.redo.bind(this.area), this._updateActionSensitivity.bind(this));
         this.eraseButton = new ActionButton(_("Erase"), 'edit-clear-all-symbolic', this.area.deleteLastElement.bind(this.area), this._updateActionSensitivity.bind(this));
         this.smoothButton = new ActionButton(_("Smooth"), Files.Icons.SMOOTH, this.area.smoothLastElement.bind(this.area), this._updateActionSensitivity.bind(this));
         this.eraseButton.child.add_style_class_name('draw-on-your-screen-menu-destructive-button');
-        this.smoothButton.child.add_style_class_name('draw-on-your-screen-menu-destructive-button');
         getActor(groupItem).add_child(this.undoButton);
         getActor(groupItem).add_child(this.redoButton);
         getActor(groupItem).add_child(this.eraseButton);
@@ -309,7 +308,7 @@ var DrawingMenu = new Lang.Class({
     
     _updateActionSensitivity: function() {
         this.undoButton.child.reactive = this.area.elements.length > 0;
-        this.redoButton.child.reactive = this.area.undoneElements.length > 0;
+        this.redoButton.child.reactive = this.area.undoneElements.length > 0 || (this.area.elements.length && this.area.elements[this.area.elements.length - 1].canUndo);
         this.eraseButton.child.reactive = this.area.elements.length > 0;
         this.smoothButton.child.reactive = this.area.elements.length > 0 && this.area.elements[this.area.elements.length - 1].shape == this.drawingTools.NONE;
         this.saveButton.child.reactive = this.area.elements.length > 0;

schemas/org.gnome.shell.extensions.draw-on-your-screen.gschema.xml

@@ -170,7 +170,7 @@
     </key>
     <key type="as" name="redo">
       <default>["&lt;Primary&gt;&lt;Shift&gt;z"]</default>
-      <summary>Redo last brushstroke</summary>
+      <summary>Redo</summary>
     </key>
     <key type="as" name="save-as-json">
       <default>["&lt;Primary&gt;s"]</default>
@@ -340,7 +340,7 @@
     </key>
     <key type="as" name="undo">
       <default>["&lt;Primary&gt;z"]</default>
-      <summary>Undo last brushstroke</summary>
+      <summary>Undo</summary>
     </key>
   </schema>
 </schemalist>