Store user selected filePath on the Piskel instance stored in pskl.app.piskelController. Getter and Setter in PublicPiskelController for filePath.

src/js/controller/piskel/PublicPiskelController.js

@@ -136,6 +136,14 @@
     return this.piskelController.piskel;
   };
 
+  ns.PublicPiskelController.prototype.setSavePath = function (savePath) {
+    this.piskelController.piskel.savePath = savePath;
+  }
+
+  ns.PublicPiskelController.prototype.getSavePath = function () {
+    return this.piskelController.piskel.savePath;
+  }
+
   ns.PublicPiskelController.prototype.raiseSaveStateEvent_ = function (fn, args) {
     $.publish(Events.PISKEL_SAVE_STATE, {
       type : pskl.service.HistoryService.REPLAY_NO_SNAPSHOT,

src/js/controller/settings/SaveController.js

@@ -165,15 +165,21 @@
   ns.SaveController.prototype.saveFileDesktop_ = function () {
     this.beforeSaving_();
     var serialized = pskl.app.piskelController.serialize();
-    // TODO: hold on to the full path to the file:
-    var fullSavePath = null;
-    // TODO: if we already have a filename (and we are sure this is the same document!!!)
-    // then save over the old file without opening a save dialog (using nodejs 'fs' api)
-    pskl.utils.FileUtils.desktopSaveAs(serialized, null, function (filename) {
-      this.onSaveSuccess_();
-      this.afterSaving_();
-      fullSavePath = filename;
-    }.bind(this));
+    var savePath = pskl.app.piskelController.getSavePath();
+    // if we already have a filename, just save the file (using nodejs 'fs' api)
+    if (savePath !== null) {
+      pskl.utils.FileUtils.desktopSaveToFile(serialized, savePath, function () {
+        this.onSaveSuccess_();
+        this.afterSaving_();
+      }.bind(this));
+    } else {
+      // "save as" = open a save dialog, and store the returned save path
+      pskl.utils.FileUtils.desktopSaveAs(serialized, null, function (selectedSavePath) {
+        this.onSaveSuccess_();
+        this.afterSaving_();
+        pskl.app.piskelController.setSavePath(selectedSavePath);
+      }.bind(this));
+    }
   }
 
   ns.SaveController.prototype.getName = function () {

src/js/model/Piskel.js

@@ -20,6 +20,10 @@
       this.height = height;
 
       this.descriptor = descriptor;
+
+      /** @type {String} */
+      this.savePath = null;
+
     } else {
       throw 'Missing arguments in Piskel constructor : ' + Array.prototype.join.call(arguments, ",");
     }