using System;
using System.Collections.Generic;
using System.IO;

namespace WX.CRM.Common
{
    /// <summary>
    /// net use 建立映射的功能模块
    /// </summary>
    /// /*不建议指定盘符。因为IIS的网站默认是在IUser账户下运行的,而映射只针对'建立时的账户'有效。所以IUser下的映射又是无法预知的。所以应该建立连接后，仍然使用共享地址访问文件或目录。*/
    public static class NetUseHelper
    {
        /// <summary>
        /// 所有支持的驱动器号
        /// </summary>
        static readonly string[] driveNames = { "ZYXWVUTSRQPONMLKJIHGFEDC" };
        /// <summary>
        /// 建立映射
        /// </summary>
        /// <param name="sharename">共享路径</param>
        /// <param name="user">用户名。为 null 不指定用户
        /// <para>请务必使用共享服务器的IP或PC名称+用户名，例如：192.168.1.1\User。否则可能引起1312错误</para>
        /// </param>
        /// <param name="password">密码。为 null 不指定密码</param>
        /// <param name="devicename">磁盘驱动器名称，例如（C:）。为 null 自动分配驱动器号 。为 空 不指定驱动器号</param>
        /// <returns>驱动器名称</returns> 
        public static string Build(string sharename, string user = null, string password = null, string devicename = null)
        {
            if (devicename != string.Empty)//为空时在已有的列表中得不到信息，所以不用判断了
            {
                //得到当前所有的映射驱动器及地址
                var netUseList = GetAllDevic();

                //标准格式
                sharename = @"\\" + sharename.Trim('\\');

                if (devicename == null)//自动分配驱动器号
                {
                    for (int i = 0; i < driveNames.Length; i++)
                    {
                        string name = driveNames[i];
                        if (netUseList.ContainsKey(name)) continue;//已存在
                        devicename = name;
                        break;

                    }
                    if (devicename == null)
                        throw new ArgumentException("当前没有可用的驱动器号.");
                }
                else
                {
                    //标准格式
                    devicename = devicename.Trim('\\', ':');

                    //判断是否已存在相同的共享
                    foreach (var kv in netUseList)
                    {
                        if (kv.Value == null) continue;
                        //驱动器号和共享路径一致
                        if (string.Equals(kv.Key, devicename, StringComparison.CurrentCultureIgnoreCase)
                            && string.Equals(kv.Value, sharename, StringComparison.CurrentCultureIgnoreCase))
                            return devicename;//已存在，返回
                    }
                    //共享没在用，但其他占用驱动器号
                    if (netUseList.ContainsKey(devicename))
                        throw new ArgumentException("驱动器号" + devicename + "正在使用.");
                }

            }
            if (!Directory.Exists(sharename))
            {
                //LogHelper.Info("sharename:" + sharename);
                using (System.Diagnostics.Process myProcess = new System.Diagnostics.Process())
                {
                    string command = string.Format(@"use ");
                    if (devicename != string.Empty)
                    {
                        command += devicename.Trim('\\', ':') + ": ";

                    }
                    command += string.Format("\"{0}\" ", sharename);
                    if (user != null)
                    {
                        command += string.Format(@"""{0}"" /user:""{1}"" ", password, user);
                    }
                    //System.IO.File.AppendAllText(@"D:\web\WXCRM.WxService.Test\log.txt", command);
                    //通过net use的命令 创建共享。
                    System.Diagnostics.ProcessStartInfo info = new System.Diagnostics.ProcessStartInfo("net ", command);
                    info.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
                    info.CreateNoWindow = true;
                    info.UseShellExecute = false;
                    info.RedirectStandardError = true;
                    myProcess.StartInfo = info;
                    myProcess.Start();
                    myProcess.WaitForExit(6000);
                    string errormsg = myProcess.StandardError.ReadToEnd();

                    myProcess.Close();

                    if (!string.IsNullOrEmpty(errormsg))
                        throw new InvalidOperationException(errormsg);
                }
            }
            return devicename;
        }

        /// <summary>
        /// 获取当前所有的驱动器
        /// <para>Key:盘符</para>
        /// <para>Value:盘符ProviderName(源路径信息)。如果为本地磁盘则为null</para>
        /// </summary>
        /// <returns></returns>
        private static Dictionary<string, string> GetAllDevic()
        {
            //得到当前所有的驱动器
            var devicList = new Dictionary<string, string>(StringComparer.CurrentCultureIgnoreCase);
            var selectQuery = new System.Management.SelectQuery("select * from win32_logicaldisk");
            var searcher = new System.Management.ManagementObjectSearcher(selectQuery);

            foreach (System.Management.ManagementObject disk in searcher.Get())
            {
                var devName = disk["DeviceID"];
                if (devName == null)
                    devName = disk["Name"];
                var diskName = devName.ToString().Trim('\\', ':');
                devicList.Add(diskName, null);
                var access = disk["Access"];
                if (access == null || access.ToString() != "0") continue;//不可访问
                var drivetype = disk["DriveType"];
                if (drivetype == null || drivetype.ToString() != "4") continue;//不是网络驱动器
                var providername = disk["ProviderName"];
                if (providername == null) continue;//没有映射源

                devicList[diskName] = providername.ToString();
            }
            return devicList;
        }
    }
}