feat: 添加同路径互斥锁

src/MaaWpfGui/App.xaml.cs

@@ -11,7 +11,10 @@
 // but WITHOUT ANY WARRANTY
 // </copyright>
 
+using System;
 using System.Diagnostics;
+using System.IO;
+using System.Threading;
 using System.Windows;
 using System.Windows.Documents;
 
@@ -31,9 +34,36 @@ namespace MaaWpfGui
             }
         }
 
+        private Mutex _mutex;
+
         protected override void OnStartup(StartupEventArgs e)
         {
+            // 设置互斥量的名称
+            string mutexName = "MAA_" + Directory.GetCurrentDirectory().Replace("\\", "_").Replace(":", string.Empty);
+            _mutex = new Mutex(true, mutexName);
+
+            if (!_mutex.WaitOne(TimeSpan.Zero, true))
+            {
+                // 这里还没加载语言包，就不 GetString 了
+                MessageBox.Show("同一路径下只能启动一个实例！\n\n" +
+                                "同一路徑下只能啟動一個實例！\n\n" +
+                                "Only one instance can be launched under the same path!\n\n" +
+                                "同じパスの下で1つのインスタンスしか起動できません！\n\n" +
+                                "동일한 경로에는 하나의 인스턴스만 실행할 수 있습니다!");
+                Current.Shutdown();
+                return;
+            }
+
             base.OnStartup(e);
         }
+
+        protected override void OnExit(ExitEventArgs e)
+        {
+            // 释放互斥量
+            _mutex.ReleaseMutex();
+            _mutex.Dispose();
+
+            base.OnExit(e);
+        }
     }
 }