using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Runtime.InteropServices.ComTypes;
using System.Windows.Forms;

namespace WindowsFormsApp1
{
    class AutoStart
    {
        /// <summary>
        /// 快捷方式名称-任意自定义
        /// </summary>
        private const string QuickName = "VisionProSystem";

        /// <summary>
        /// 自动获取系统自动启动目录
        /// </summary>
        private string systemStartPath { get { return Environment.GetFolderPath(Environment.SpecialFolder.Startup); } }

        /// <summary>
        /// 自动获取程序完整路径
        /// </summary>
        private string appAllPath
        {
            get
            {
                string path = Process.GetCurrentProcess().MainModule.FileName;
                if (path.Contains(".vshost"))
                {
                    path = path.Replace(".vshost", "");
                }
                return path;
            }
        }

        /// <summary>
        /// 自动获取桌面目录
        /// </summary>
        private string desktopPath { get { return Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory); } }

        /// <summary>
        /// 设置开机自动启动和桌面快捷方式，默认创建
        /// --只需要调用改方法就可以了
        /// </summary>
        /// <param name="onOff">自启开关</param>
        public void SetMeAutoStart(bool autostart = true, bool desktop = true)
        {
            if (autostart)//开机启动
            {
                //获取启动路径应用程序快捷方式的路径集合
                List<string> shortcutPaths = GetQuickFromFolder(systemStartPath, appAllPath);
                //存在2个以快捷方式则保留一个快捷方式-避免重复多于
                if (shortcutPaths.Count >= 2)
                {
                    for (int i = 1; i < shortcutPaths.Count; i++)
                    {
                        DeleteFile(shortcutPaths[i]);
                    }
                }
                else if (shortcutPaths.Count < 1)//不存在则创建快捷方式
                {
                    CreatShortcut(systemStartPath, QuickName, appAllPath, "Alley@NOVO");
                }
            }
            else//开机不启动
            {
                //获取启动路径应用程序快捷方式的路径集合
                List<string> shortcutPaths = GetQuickFromFolder(systemStartPath, appAllPath);
                //存在快捷方式则遍历全部删除
                if (shortcutPaths.Count > 0)
                {
                    for (int i = 0; i < shortcutPaths.Count; i++)
                    {
                        DeleteFile(shortcutPaths[i]);
                    }
                }
            }
            if (desktop)
            {
                //创建桌面快捷方式
                CreateDesktopQuick(desktopPath, QuickName, appAllPath);
            }

        }

        /// <summary>
        /// 获取指定文件夹下指定应用程序的快捷方式路径集合
        /// </summary>
        /// <param name="directory">文件夹</param>
        /// <param name="targetPath">目标应用程序路径</param>
        /// <returns>目标应用程序的快捷方式</returns>
        private List<string> GetQuickFromFolder(string directory, string targetPath)
        {
            List<string> tempStrs = new List<string>();
            tempStrs.Clear();
            string tempStr = null;
            string[] files = Directory.GetFiles(directory, "*.lnk");
            if (files == null || files.Length < 1)
            {
                return tempStrs;
            }
            for (int i = 0; i < files.Length; i++)
            {
                tempStr = GetAppPathFromQuick(files[i]);
                if (tempStr == targetPath)
                {
                    tempStrs.Add(files[i]);
                }
            }
            return tempStrs;
        }

        /// <summary>
        /// 获取快捷方式的目标文件路径-用于判断是否已经开启了自动启动
        /// </summary>
        /// <param name="shortcutPath"></param>
        /// <returns></returns>
        private string GetAppPathFromQuick(string shortcutPath)
        {
            string sfile = Path.Combine(desktopPath, QuickName + ".lnk");
            IShellLink link = (IShellLink)new ShellLink();
            IPersistFile file = (IPersistFile)link;
            try
            {
                file.Load(sfile, 2);
            }
            catch (Exception)
            {
                return null;
            }

            StringBuilder sb = new StringBuilder(256);
            link.GetPath(sb, sb.Capacity, IntPtr.Zero, 2);
            return sb.ToString();
        }

        /// <summary>
        /// 根据路径删除文件-用于取消自启时从计算机自启目录删除程序的快捷方式
        /// </summary>
        /// <param name="path">路径</param>
        private void DeleteFile(string path)
        {
            FileAttributes attr = System.IO.File.GetAttributes(path);
            if (attr == FileAttributes.Directory)
            {
                Directory.Delete(path, true);
            }
            else
            {
                System.IO.File.Delete(path);
            }
        }

        /// <summary>
        /// 在桌面上创建快捷方式
        /// </summary>
        /// <param name="desktopPath">桌面地址</param>
        /// <param name="appPath">应用路径</param>
        private void CreateDesktopQuick(string DesktopPath = "", string quickName = QuickName, string AppPath = "")
        {
            DesktopPath = desktopPath;
            AppPath = appAllPath;
            List<string> shortcutPaths = GetQuickFromFolder(desktopPath, AppPath);
            //如果没有则创建
            if (shortcutPaths.Count < 1)
            {
                CreatShortcut(desktopPath, quickName, AppPath, "Alley@NOVO");
            }
        }

        [ComImport]
        [Guid("00021401-0000-0000-C000-000000000046")]
        internal class ShellLink
        {
        }
        [ComImport]
        [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
        [Guid("000214F9-0000-0000-C000-000000000046")]
        internal interface IShellLink
        {
            void GetPath([Out, MarshalAs(UnmanagedType.LPWStr)] StringBuilder pszFile, int cchMaxPath, IntPtr pfd, int fFlags);
            void GetIDList(out IntPtr ppidl);
            void SetIDList(IntPtr pidl);
            void GetDescription([Out, MarshalAs(UnmanagedType.LPWStr)] StringBuilder pszName, int cchMaxName);
            void SetDescription([MarshalAs(UnmanagedType.LPWStr)] string pszName);
            void GetWorkingDirectory([Out, MarshalAs(UnmanagedType.LPWStr)] StringBuilder pszDir, int cchMaxPath);
            void SetWorkingDirectory([MarshalAs(UnmanagedType.LPWStr)] string pszDir);
            void GetArguments([Out, MarshalAs(UnmanagedType.LPWStr)] StringBuilder pszArgs, int cchMaxPath);
            void SetArguments([MarshalAs(UnmanagedType.LPWStr)] string pszArgs);
            void GetHotkey(out short pwHotkey);
            void SetHotkey(short wHotkey);
            void GetShowCmd(out int piShowCmd);
            void SetShowCmd(int iShowCmd);
            void GetIconLocation([Out, MarshalAs(UnmanagedType.LPWStr)] StringBuilder pszIconPath, int cchIconPath, out int piIcon);
            void SetIconLocation([MarshalAs(UnmanagedType.LPWStr)] string pszIconPath, int iIcon);
            void SetRelativePath([MarshalAs(UnmanagedType.LPWStr)] string pszPathRel, int dwReserved);
            void Resolve(IntPtr hwnd, int fFlags);
            void SetPath([MarshalAs(UnmanagedType.LPWStr)] string pszFile);
        }

        /// <summary>
        ///  向目标路径创建指定文件的快捷方式
        /// </summary>
        /// <param name="desktopPath">快捷方式路径</param>
        /// <param name="quickname">快捷方式名</param>
        /// <param name="apppath">App路径</param>
        /// <param name="description">提示信息</param>
        private void CreatShortcut(string desktopPath, string quickname, string apppath, string description)
        {
            IShellLink link = (IShellLink)new ShellLink();
            link.SetDescription(description);
            link.SetPath(apppath); //指定文件路径

            IPersistFile file = (IPersistFile)link;

            string sfile = Path.Combine(desktopPath, quickname + ".lnk");
            if (File.Exists(sfile))
                File.Delete(sfile);
            file.Save(sfile, false);  //快捷方式保存到桌面
        }
    }
}