[libgames-support] Allow importing scores from Vala games

[Michael Catanzaro <mcatanzaro src gnome org>]

commit 1c8a739eac99416c0e068de0a5b124ba50861732
Author: Michael Catanzaro <mcatanzaro igalia com>
Date:   Sun Feb 14 15:07:38 2016 -0600

    Allow importing scores from Vala games

 games/Makefile.am                       |   15 +++--
 games/scores/history-file-importer.vala |   92 +++++++++++++++++++++++++++++++
 2 files changed, 100 insertions(+), 7 deletions(-)
---
diff --git a/games/Makefile.am b/games/Makefile.am
index b41dfd7..6512a4f 100644
--- a/games/Makefile.am
+++ b/games/Makefile.am
@@ -1,13 +1,14 @@
 lib_LTLIBRARIES = libgames-support.la
 
 libgames_support_la_SOURCES = \
-       config.vapi                     \
-       gridframe.vala                  \
-       scores/category.vala            \
-       scores/context.vala             \
-       scores/dialog.vala              \
-       scores/directory-importer.vala  \
-       scores/importer.vala            \
+       config.vapi                             \
+       gridframe.vala                          \
+       scores/category.vala                    \
+       scores/context.vala                     \
+       scores/dialog.vala                      \
+       scores/directory-importer.vala          \
+       scores/history-file-importer.vala       \
+       scores/importer.vala                    \
        scores/score.vala
 
 libgames_support_la_CFLAGS = \
diff --git a/games/scores/history-file-importer.vala b/games/scores/history-file-importer.vala
new file mode 100644
index 0000000..b3f5ea7
--- /dev/null
+++ b/games/scores/history-file-importer.vala
@@ -0,0 +1,92 @@
+/* -*- Mode: vala; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ *
+ * Copyright © 2016 Michael Catanzaro <mcatanzaro gnome org>
+ *
+ * This file is part of libgames-support.
+ *
+ * libgames-support is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * libgames-support is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with libgames-support.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+namespace Games {
+namespace Scores {
+
+/* Imports scores from a Vala game's history file directory, where each category
+ * of scores is saved together in the same file. This is the format used by
+ * games that were converted to Vala before switching to libgames-support. This
+ * class should probably be used by Klotski, Mines, Swell Foop, Mahjongg,
+ * Tetravex, Quadrapassel, and nothing else.
+ */
+public class HistoryFileImporter : Importer
+{
+    /* A function provided by the game that converts a line in its history file
+     * to a Score and Category we can use.
+     */
+    public delegate void HistoryConvertFunc (string line, out Score score, out Category category);
+    private HistoryConvertFunc history_convert;
+
+    public HistoryFileImporter (HistoryConvertFunc history_convert)
+    {
+        this.history_convert = (line, out score, out category) => {
+            history_convert (line, out score, out category);
+        };
+    }
+
+    /* Copied from Robert's Vala games. This is useful for games to use when
+     * implementing their HistoryConvertFuncs.
+     */
+    public static DateTime? parse_date (string date)
+    {
+        if (date.length < 19 || date[4] != '-' || date[7] != '-' || date[10] != 'T' || date[13] != ':' || 
date[16] != ':')
+            return null;
+
+        var year = int.parse (date.substring (0, 4));
+        var month = int.parse (date.substring (5, 2));
+        var day = int.parse (date.substring (8, 2));
+        var hour = int.parse (date.substring (11, 2));
+        var minute = int.parse (date.substring (14, 2));
+        var seconds = int.parse (date.substring (17, 2));
+        var timezone = date.substring (19);
+
+        return new DateTime (new TimeZone (timezone), year, month, day, hour, minute, seconds);
+    }
+
+    /* Each game uses a somewhat different format for its scores; one game might
+     * use one column to store the category, while another might use two or
+     * more. Pass the game one line of the history file at a time, and let the
+     * game convert it to a Score and Category for us.
+     */
+    protected override void importOldScores (Context context, File new_scores_dir) throws GLib.Error
+    {
+        var history_filename = Path.build_filename (new_scores_dir.get_path (), "..", "history", null);
+        debug ("Importing scores from %s", history_filename);
+
+        var stream = FileStream.open (history_filename, "r");
+        string line;
+        while ((line = stream.read_line ()) != null)
+        {
+            Score score;
+            Category category;
+            history_convert (line, out score, out category);
+            if (score == null || category == null)
+                warning ("Failed to import from %s score line %s", history_filename, line);
+            context.add_score_sync (score, category);
+        }
+
+        var history_file = File.new_for_path (history_filename);
+        history_file  delete ();
+    }
+}
+
+} /* namespace Scores */
+} /* namespace Games */