From ba5a747ac9e1b83ff38b28884d86952895d34ab9 Mon Sep 17 00:00:00 2001
From: Shivam <s.r.v.ramkisoen@umail.leidenuniv.nl>
Date: Mon, 8 Jun 2020 03:03:57 +0200
Subject: [PATCH] Implement migration for TournamentStorage

---
 osu.Game.Tournament/TournamentStorage.cs | 75 ++++++++++++++++++++++--
 1 file changed, 70 insertions(+), 5 deletions(-)

diff --git a/osu.Game.Tournament/TournamentStorage.cs b/osu.Game.Tournament/TournamentStorage.cs
index e5d19831d0..48eef76a28 100644
--- a/osu.Game.Tournament/TournamentStorage.cs
+++ b/osu.Game.Tournament/TournamentStorage.cs
@@ -1,10 +1,14 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using System;
+using System.Linq;
+using System.Threading;
 using osu.Framework.IO.Stores;
 using osu.Framework.Logging;
 using osu.Framework.Platform;
 using osu.Game.IO;
+using System.IO;
 using osu.Game.Tournament.Configuration;
 
 namespace osu.Game.Tournament
@@ -32,16 +36,77 @@ public TournamentStorage(GameHost host)
             this.host = host;
 
             storageConfig = new TournamentStorageManager(host.Storage);
-            var customTournamentPath = storageConfig.Get<string>(StorageConfig.CurrentTournament);
+            var currentTournament = storageConfig.Get<string>(StorageConfig.CurrentTournament);
 
-            if (!string.IsNullOrEmpty(customTournamentPath))
+            if (!string.IsNullOrEmpty(currentTournament))
             {
-                ChangeTargetStorage(UnderlyingStorage.GetStorageForDirectory("tournaments/" + customTournamentPath));
-            } else {
-                ChangeTargetStorage(UnderlyingStorage.GetStorageForDirectory("tournaments/default"));
+                ChangeTargetStorage(UnderlyingStorage.GetStorageForDirectory("tournaments" + Path.DirectorySeparatorChar + currentTournament));
             }
+            else
+            {
+                // Migrating old storage format to the new one.
+                Migrate();
+                Logger.Log("Migrating files from old storage to new.");
+            }
+
             VideoStorage = new TournamentVideoStorage(this);
             Logger.Log("Using tournament storage: " + GetFullPath(string.Empty));
         }
+
+        private void Migrate()
+        {
+            var defaultPath = "tournaments/default";
+            var source = new DirectoryInfo(GetFullPath("tournament"));
+            var destination = new DirectoryInfo(GetFullPath(defaultPath));
+
+            Directory.CreateDirectory(destination.FullName);
+            
+            if (host.Storage.Exists("bracket.json"))
+            {   
+                Logger.Log("Migrating bracket to default tournament storage.");
+                var bracketFile = new System.IO.FileInfo(GetFullPath(string.Empty) + Path.DirectorySeparatorChar + GetFiles(string.Empty, "bracket.json").First());
+                attemptOperation(() => bracketFile.CopyTo(Path.Combine(destination.FullName, bracketFile.Name), true));
+            }
+
+            Logger.Log("Migrating other assets to default tournament storage.");
+            copyRecursive(source, destination);
+            ChangeTargetStorage(UnderlyingStorage.GetStorageForDirectory(defaultPath));
+            storageConfig.Set<string>(StorageConfig.CurrentTournament, defaultPath);
+            storageConfig.Save();
+        }
+
+        private void copyRecursive(DirectoryInfo source, DirectoryInfo destination, bool topLevelExcludes = true)
+        {
+            // based off example code https://docs.microsoft.com/en-us/dotnet/api/system.io.directoryinfo
+
+            foreach (System.IO.FileInfo fi in source.GetFiles())
+            {
+                attemptOperation(() => fi.CopyTo(Path.Combine(destination.FullName, fi.Name), true));
+            }
+
+            foreach (DirectoryInfo dir in source.GetDirectories())
+            {
+                copyRecursive(dir, destination.CreateSubdirectory(dir.Name), false);
+            }
+        }
+
+        private void attemptOperation(Action action, int attempts = 10)
+        {
+            while (true)
+            {
+                try
+                {
+                    action();
+                    return;
+                }
+                catch (Exception)
+                {
+                    if (attempts-- == 0)
+                        throw;
+                }
+
+                Thread.Sleep(250);
+            }
+        }
     }
 }