[gnome-games] retro-runner: Add trim_autosaves() and create_new_savestate_name()

[Alexander Mikhaylenko <alexm src gnome org>]

commit 466fd41e4243f69e02804bb099886e9a4bf6d1f2
Author: Yetizone <andreii lisita gmail com>
Date:   Sat Aug 10 11:32:12 2019 +0300

    retro-runner: Add trim_autosaves() and create_new_savestate_name()
    
    Change generation method for manual savestates names
    Previously the names would be generated as "New savestate (nr_savestates+1)"
    Now the names are generated based on the existing names that have the
    same pattern.
    
    E.g. If we have savestates named "New savestate 1", "A", "B" and create a new
    manual savestate then it would be called "New savestate 2"

 src/retro/retro-runner.vala | 67 +++++++++++++++++++++++++++++----------------
 1 file changed, 43 insertions(+), 24 deletions(-)
---
diff --git a/src/retro/retro-runner.vala b/src/retro/retro-runner.vala
index 9aa01b52..5e0e6063 100644
--- a/src/retro/retro-runner.vala
+++ b/src/retro/retro-runner.vala
@@ -1,6 +1,8 @@
 // This file is part of GNOME Games. License: GPL-3.0+.
 
 public class Games.RetroRunner : Object, Runner {
+       private const int MAX_AUTOSAVES = 5;
+
        public signal void game_init ();
        public signal void game_deinit ();
 
@@ -456,15 +458,9 @@ public class Games.RetroRunner : Object, Runner {
        }
 
        private Savestate create_savestate (bool is_automatic) throws Error {
-               // Decide if there are too many automatic savestates and delete the
-               // first one if so
-               var nr_automatic_savestates = count_automatic_savestates ();
-               if (is_automatic) {
-                       var max_nr_automatic_savestates = 5;
-
-                       if (nr_automatic_savestates >= max_nr_automatic_savestates)
-                               delete_last_automatic_savestate ();
-               }
+               // Make room for the new automatic savestate
+               if (is_automatic)
+                       trim_autosaves ();
 
                // Populate the savestate in tmp with data from the current state of the game
                store_save_ram_in_tmp ();
@@ -481,8 +477,7 @@ public class Games.RetroRunner : Object, Runner {
                if (is_automatic)
                        tmp_live_savestate.set_metadata_automatic (now_time, platform_prefix, get_core_id ());
                else {
-                       var nr_manual_savestates = game_savestates.length - nr_automatic_savestates;
-                       var savestate_name = _("New savestate %d").printf (nr_manual_savestates + 1);
+                       var savestate_name = create_new_savestate_name ();
 
                        tmp_live_savestate.set_metadata_manual (savestate_name, now_time, platform_prefix, 
get_core_id ());
                }
@@ -608,27 +603,51 @@ public class Games.RetroRunner : Object, Runner {
                return core;
        }
 
-       private int count_automatic_savestates () {
-               int counter = 0;
+       private string create_new_savestate_name () throws Error {
+               // A list containing the names of all savestates with name of the form "New Savestate %d"
+               var list = new List<string>();
+               var regex = new Regex (_("New savestate %s").printf ("[1-9]\\d*"));
 
                foreach (var savestate in game_savestates) {
                        if (savestate.is_automatic ())
-                               counter++;
+                               continue;
+
+                       var savestate_name = savestate.get_name ();
+
+                       if (regex.match (savestate_name))
+                               list.prepend (savestate_name);
                }
 
-               return counter;
-       }
+               list.sort (strcmp);
 
-       private void delete_last_automatic_savestate () {
-               // Delete the last automatic savestate (assume they are sorted
-               // by creation date for now)
-               Savestate last_automatic_savestate = null;
+               // Find the next available name for a new manual savestate
+               var new_savestate_name_suffix = 1;
+               foreach (var savestate_name in list) {
+                       var new_savestate_name = _("New savestate %s").printf 
(new_savestate_name_suffix.to_string ());
+                       if (savestate_name == new_savestate_name)
+                               new_savestate_name_suffix++;
+                       else
+                               break;
+               }
 
-               foreach (var savestate in game_savestates)
-                       if (savestate.is_automatic ())
-                               last_automatic_savestate = savestate;
+               return _("New savestate %s").printf (new_savestate_name_suffix.to_string ());
+       }
 
-               last_automatic_savestate.delete_from_disk ();
+       // Decide if there are too many automatic savestates and delete the
+       // last ones if so
+       private void trim_autosaves () {
+               // A new automatic savestate will be created right after this call,
+               // so counter starts from 1
+               int autosaves_counter = 1;
+
+               foreach (var savestate in game_savestates) {
+                       if (savestate.is_automatic ()) {
+                               if (autosaves_counter < MAX_AUTOSAVES)
+                                       autosaves_counter++;
+                               else
+                                       savestate.delete_from_disk ();
+                       }
+               }
        }
 }