using System;
using System.Collections.Generic;
using System.Linq;
using System.Management;
using System.Text;
using System.Threading.Tasks;

namespace Tango.Transport.Components
{
    public static class ComPortEnumerator
    {
        private class ProcessConnection
        {
            public static ConnectionOptions ProcessConnectionOptions()
            {

                ConnectionOptions options = new ConnectionOptions();
                options.Impersonation = ImpersonationLevel.Impersonate;
                options.Authentication = AuthenticationLevel.Default;
                options.EnablePrivileges = true;
                return options;
            }

            public static ManagementScope ConnectionScope(string machineName, ConnectionOptions options, string path)
            {
                ManagementScope connectScope = new ManagementScope();
                connectScope.Path = new ManagementPath(@"\\" + machineName + path);
                connectScope.Options = options;
                connectScope.Connect();
                return connectScope;
            }
        }

        public class ComPortInfo
        {
            public string Port { get; set; }
            public string Description { get; set; }

            public override string ToString()
            {
                return String.Format("{0}, {1}", Port, Description);
            }
        }

        public static List<ComPortInfo> EnumerateComPorts()
        {
            List<ComPortInfo> comPortInfoList = new List<ComPortInfo>();

            ConnectionOptions options = ProcessConnection.ProcessConnectionOptions();
            ManagementScope connectionScope = ProcessConnection.ConnectionScope(Environment.MachineName, options, @"\root\CIMV2");
            ObjectQuery objectQuery = new ObjectQuery("SELECT * FROM Win32_PnPEntity WHERE ConfigManagerErrorCode = 0");
            ManagementObjectSearcher comPortSearcher = new ManagementObjectSearcher(connectionScope, objectQuery);

            using (comPortSearcher)
            {
                string caption = null;

                foreach (ManagementObject obj in comPortSearcher.Get())
                {
                    if (obj != null)
                    {
                        object captionObj = obj["Caption"];

                        if (captionObj != null)
                        {
                            caption = captionObj.ToString();
                            if (caption.Contains("(COM"))
                            {
                                ComPortInfo comPortInfo = new ComPortInfo();
                                comPortInfo.Port = caption.Substring(caption.LastIndexOf("(COM")).Replace("(", string.Empty).Replace(")", string.Empty);
                                comPortInfo.Description = caption;
                                comPortInfoList.Add(comPortInfo);
                            }
                        }
                    }
                }
            }
            return comPortInfoList;
        }
    }
}