using System;
using System.Threading;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using APS7100TestTool.Forms;

namespace APS7100TestTool
{
    static class Program
    {
        // 用于单实例检查的 Mutex 名称
        private const string MutexName = "GoodWill_APS7100TestTool_SingleInstance";
        
        // Windows API 用于激活已存在的窗口
        [DllImport("user32.dll")]
        private static extern bool SetForegroundWindow(IntPtr hWnd);
        
        [DllImport("user32.dll")]
        private static extern bool ShowWindow(IntPtr hWnd, int nCmdShow);
        
        [DllImport("user32.dll")]
        private static extern IntPtr FindWindow(string lpClassName, string lpWindowName);
        
        private const int SW_RESTORE = 9;
        private const int SW_SHOW = 5;

        /// <summary>
        /// 应用程序的主入口点。
        /// </summary>
        [STAThread]
        static void Main()
        {
            // 尝试创建 Mutex，如果已存在则说明程序已在运行
            bool createdNew;
            using (Mutex mutex = new Mutex(true, MutexName, out createdNew))
            {
                if (!createdNew)
                {
                    // 程序已在运行，尝试激活已存在的窗口
                    IntPtr hWnd = FindWindow(null, "固纬电源测试工具");
                    if (hWnd != IntPtr.Zero)
                    {
                        ShowWindow(hWnd, SW_RESTORE);
                        SetForegroundWindow(hWnd);
                    }
                    
                    MessageBox.Show("程序已在运行中！\n请查看系统托盘或任务栏。", 
                        "固纬电源测试工具", 
                        MessageBoxButtons.OK, 
                        MessageBoxIcon.Information);
                    return;
                }

                Application.EnableVisualStyles();
                Application.SetCompatibleTextRenderingDefault(false);
                Application.SetHighDpiMode(HighDpiMode.SystemAware);
                Application.Run(new MainForm());
            }
        }
    }
}