[gnome-tetravex] No empty Scores dialog.

[Arnaud B. <arnaudb src gnome org>]

commit e1b67d953fdc5a6d0039c9e20ad4a1cfaf6595cd
Author: Arnaud Bonatti <arnaud bonatti gmail com>
Date:   Fri Oct 11 16:43:52 2019 +0200

    No empty Scores dialog.
    
    Popup a MessageDialog instead.

 src/gnome-tetravex.vala | 25 ++++++++++++++++++-------
 src/history.vala        |  6 ++++++
 2 files changed, 24 insertions(+), 7 deletions(-)
---
diff --git a/src/gnome-tetravex.vala b/src/gnome-tetravex.vala
index 1e268a3..2dbfe49 100644
--- a/src/gnome-tetravex.vala
+++ b/src/gnome-tetravex.vala
@@ -483,7 +483,7 @@ private class Tetravex : Gtk.Application
         if (puzzle.game_in_progress && !puzzle.is_solved)
         {
             MessageDialog dialog = new MessageDialog (window,
-                                                      DialogFlags.MODAL,
+                                                      DialogFlags.MODAL | DialogFlags.DESTROY_WITH_PARENT,
                                                       MessageType.QUESTION,
                                                       ButtonsType.NONE,
         /* Translators: popup dialog main text; appearing when user clicks "New Game" from the hamburger 
menu, while a game is started; possible answers are "Keep playing"/"Start New Game" */
@@ -511,11 +511,22 @@ private class Tetravex : Gtk.Application
     {
         if (scores_dialog_visible)
             return;
-
         scores_dialog_visible = true;
-        ScoreDialog dialog = new ScoreDialog (history, puzzle.size, puzzle.is_solved ? last_history_entry : 
null);
-        dialog.set_modal (true);
-        dialog.set_transient_for (window);
+
+        Dialog dialog;
+        if (history.is_empty ())
+            dialog = new MessageDialog (window,
+                                        DialogFlags.MODAL | DialogFlags.DESTROY_WITH_PARENT,
+                                        MessageType.INFO,
+                                        ButtonsType.CLOSE,
+            /* Translators: popup dialog main text; appearing when user clicks the "Scores" entry of the 
hamburger menu, while not having finished any game yet */
+                                        _("Looks like you haven’t finished a game yet.\n\nTry maybe a 2 × 2 
grid, they are easy. 🙂️"));
+        else
+        {
+            dialog = new ScoreDialog (history, puzzle.size, puzzle.is_solved ? last_history_entry : null);
+            dialog.set_modal (true);
+            dialog.set_transient_for (window);
+        }
 
         dialog.run ();
         dialog.destroy ();
@@ -538,7 +549,7 @@ private class Tetravex : Gtk.Application
     private void solve_cb ()
     {
         MessageDialog dialog = new MessageDialog (window,
-                                                  DialogFlags.MODAL,
+                                                  DialogFlags.MODAL | DialogFlags.DESTROY_WITH_PARENT,
                                                   MessageType.QUESTION,
                                                   ButtonsType.NONE,
         /* Translators: popup dialog main text; appearing when user clicks the "Give up" button in the 
bottom bar; possible answers are "Keep playing"/"Give up" */
@@ -580,7 +591,7 @@ private class Tetravex : Gtk.Application
         if (puzzle.game_in_progress && !puzzle.is_solved)
         {
             MessageDialog dialog = new MessageDialog (window,
-                                                      DialogFlags.MODAL,
+                                                      DialogFlags.MODAL | DialogFlags.DESTROY_WITH_PARENT,
                                                       MessageType.QUESTION,
                                                       ButtonsType.NONE,
         /* Translators: popup dialog main text; appearing when user changes size from the hamburger menu 
submenu, while a game is started; possible answers are "Keep playing"/"Start New Game" */
diff --git a/src/history.vala b/src/history.vala
index 13547c7..80c810d 100644
--- a/src/history.vala
+++ b/src/history.vala
@@ -105,6 +105,12 @@ private class History : Object
         return entries.position (best_time_item);
     }
 
+    internal bool is_empty ()
+    {
+        unowned List<HistoryEntry>? first_entry = entries.first ();
+        return first_entry == null;
+    }
+
     /*\
     * * loading
     \*/