Updated DBSyncWatcher and Syncer

Added Locking system, so that we don't try to access the same file with
both read and write functions at the same time causing an locked
exception on the file when watching it.

FreeTubeSyncer/Library/DBSyncWatcher.cs

@@ -2,6 +2,7 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Text.Json;
+using System.Threading;
 
 namespace FreeTubeSyncer.Library;
 
@@ -13,6 +14,8 @@ public class DBSyncWatcher
     public delegate void DatabaseChange(string db, string value);
     public event DatabaseChange OnDatabaseChange;
 
+    public bool Locked = false;
+
     public DBSyncWatcher(string path)
     {
         _watcher = new FileSystemWatcher(path);
@@ -32,6 +35,11 @@ public class DBSyncWatcher
     {
         if (e.ChangeType != WatcherChangeTypes.Changed) return;
 
+        while (Locked)
+        {
+            Thread.Sleep(100);
+        }
+
         var dbName = Path.GetFileName(e.FullPath);
 
         if (!WatchFiles.Keys.Contains(dbName)) return;

FreeTubeSyncer/REST/Syncer.cs

@@ -28,14 +28,16 @@ public class Syncer<T> : ISyncer where T : class, IDataModel, new()
     private string _dbPath;
     private string _dbName;
     private string _restEndpoint;
+    private DBSyncWatcher _watcher;
 
     private bool _isDirty = false;
     private bool _syncing = false;
 
     public Syncer(DBSyncWatcher watcher, string dbPath, string dbName, string restEndpoint)
     {
-        watcher.WatchFiles[dbName] = typeof(T);
+        _watcher = watcher;
-        watcher.OnDatabaseChange += HandleDatabaseChange;
+        _watcher.WatchFiles[dbName] = typeof(T);
+        _watcher.OnDatabaseChange += HandleDatabaseChange;
         _client = new RestClient(new RestClientOptions("http://192.168.1.30:5050"));
         _dbPath = dbPath;
         _dbName = dbName;
@@ -138,6 +140,7 @@ public class Syncer<T> : ISyncer where T : class, IDataModel, new()
         var json = new List<string>();
         foreach (var entry in _entries)
             json.Add(entry.JsonData());
+        _watcher.Locked = true;
         using (var fh = File.OpenWrite(_dbPath))
         {
             foreach (var line in json)
@@ -145,6 +148,7 @@ public class Syncer<T> : ISyncer where T : class, IDataModel, new()
             fh.Flush();
             fh.Close();
         }
+        _watcher.Locked = false;
         Console.WriteLine($"Updated {_dbPath}.");
         _isDirty = false;
         _syncing = false;