using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Management;
using System.Reflection;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using Microsoft.Win32;

namespace Eugen.ESystem.Windows.Info
{
    public class WindowsInfo
    {
        #region Version und Copyright
        // Version und Copyright
        static string dllName = Path.GetFileNameWithoutExtension(System.Reflection.Assembly.GetExecutingAssembly().GetName().CodeBase); //Den Programmnamen auslesen
        static string dllVersion = System.Reflection.Assembly.GetExecutingAssembly().GetName().Version.ToString();
        static object[] attributes = Assembly.GetExecutingAssembly().GetCustomAttributes(typeof(AssemblyCopyrightAttribute), false);
        static string copyright = GenerateCopyright();

        //Assembly Datum und Zeit
        static DateTime value = AssemblyDateTime();
        static string date = value.ToShortDateString();
        static string time = value.ToLongTimeString();

        private static DateTime AssemblyDateTime()
        {
            var version = System.Reflection.Assembly.GetExecutingAssembly().GetName().Version;
            var buildDateTime = new DateTime(2000, 1, 1).Add(new TimeSpan(TimeSpan.TicksPerDay * version.Build + TimeSpan.TicksPerSecond * 2 * version.Revision));
            //Tage seit dem 1. Januar 2000 und Sekunden seit Mitternacht, (multiplizier mit 2 ergibt das Original)
            return buildDateTime;
        }

        private static string CurrentYear()
        {
            DateTime dtn = DateTime.Now;
            return dtn.Year.ToString();
        }

        private static string StartYear()
        {
            string startYear = "";
            if (((AssemblyCopyrightAttribute)attributes[0]).Copyright.Contains("Copyright © "))
            {
                startYear = ((AssemblyCopyrightAttribute)attributes[0]).Copyright.Replace("Copyright © ", "");
                while (startYear.StartsWith(" "))
                {
                    startYear = startYear.Remove(0, 1);
                }

                if (startYear.Contains("-"))
                {
                    startYear = startYear.Remove(startYear.IndexOf("-"));
                }
                else
                {
                    startYear = startYear.Remove(startYear.IndexOf(" "));
                }
                return startYear;
            }
            else
            {
                DateTime dtn = DateTime.Now;
                return dtn.Year.ToString();
            }
        }

        private static string GenerateCopyright()
        {
            string startYear = StartYear();
            string currentYear = CurrentYear();

            if (startYear == currentYear)
            {
                return ((AssemblyCopyrightAttribute)attributes[0]).Copyright;
            }
            else
            {
                string temp = ((AssemblyCopyrightAttribute)attributes[0]).Copyright;
                string start = temp.Remove(temp.IndexOf(startYear) - 1);
                string end = (temp.Remove(0, temp.IndexOf(" by")));

                return String.Concat(start, " ", startYear, "-", currentYear, end);
            }
        }
        #endregion

        #region DLL-Info
        /// <summary>
        /// Contains the name of the program file
        /// </summary>
        public static string DllName { set; get; }

        /// <summary>
        /// Contains the version of the program file
        /// </summary>
        public static string DllVersion { set; get; }

        /// <summary>
        /// Contains the copyright notice
        /// </summary>
        public static string Copyright { set; get; }

        private static void SetDllInfo()
        {
            //Name, Version und Copyright setzen
            DllName = dllName;
            DllVersion = dllVersion;
            Copyright = copyright;
        }
        #endregion

        /// <summary>
		/// Information about Windows
		/// </summary>
        static WindowsInfo()
        {
            SetDllInfo(); //Name, Version und Copyright setzen
			CollectWindowsInfomations();
		}

		#region Globale_Variablen
		/// <summary>
		/// Returns the installed operating system. E.g.: Microsoft Windows 10 Enterprise - 64-Bit
		/// </summary>
		public static string OS { set; get; }

		/// <summary>
		/// Returns the product name of the installed operating system. E.g.: Windows 10 Enterprise
		/// </summary>
		public static string ProductName { set; get; }

		/// <summary>
		/// Returns the edition ID of the installed operating system. E.g.: Enterprise
		/// </summary>
		public static string EditionId { set; get; }

		/// <summary>
		/// Returns the current version of the installed operating system. E.g.: 6.3
		/// </summary>
		public static string CurrentVersion { set; get; }

		/// <summary>
		/// Returns the current release ID of the installed operating system. E.g.: 1709
		/// </summary>
		public static string ReleaseId { set; get; }

		/// <summary>
		/// Returns the current build number of the installed operating system. E.g.: 16299
		/// </summary>
		public static string CurrentBuildNumber { set; get; }

		/// <summary>
		/// Returns the build lab of the installed operating system. E.g.: 16299.431
		/// </summary>
		public static string BuildLab { set; get; }

		/// <summary>
		/// Returns the operating system name of the installed operating system. E.g.: Microsoft Windows 10 Enterprise
		/// </summary>
		public static string OSName { set; get; }

		/// <summary>
		/// Returns the OS version string of the installed operating system. E.g.: Microsoft Windows NT 6.2.9200.0
		/// </summary>
		public static string OSVersionString { set; get; }

		/// <summary>
		/// Returns the OS version of the installed operating system. E.g.: 6.2.9200.0
		/// </summary>
		public static string OSVersion { set; get; }

		/// <summary>
		/// Returns the OS architecture of the installed operating system. E.g.: 64-Bit
		/// </summary>
		public static string OSArchitecture { set; get; }

		/// <summary>
		/// Returns the OS service pack of the installed operating system. E.g.: SP1
		/// </summary>
		public static string OSServicePack { set; get; }

		/// <summary>
		/// Returns the OS major version of the installed operating system. E.g.: 6
		/// </summary>
		public static int OSMajorVersion { set; get; }

		/// <summary>
		/// Returns the OS minor version of the installed operating system. E.g.: 2
		/// </summary>
		public static int OSMinorVersion { set; get; }

		/// <summary>
		/// Returns the OS major revision of the installed operating system. E.g.: 0
		/// </summary>
		public static int OSMajorRevision { set; get; }

		/// <summary>
		/// Returns the OS minor revision of the installed operating system. E.g.: 0
		/// </summary>
		public static int OSMinorRevision { set; get; }

		/// <summary>
		/// Returns the OS build of the installed operating system. E.g.: 9200
		/// </summary>
		public static int OSBuild { set; get; }

		/// <summary>
		/// Returns the process architecture of the installed operating system. E.g.: Win32NT
		/// </summary>
		public static string ProcessArchitecture { set; get; }
		#endregion

		OperatingSystem os = Environment.OSVersion;

        #region Methoden
		/// <summary>
        /// Collects all Windows informations
        /// </summary>
        /// <exception cref="UnableToReadOSInformationException">If a value cannot be read, an exception is thrown</exception>
        public static void CollectWindowsInfomations()
        {
			try
            {
				OS = GetOS();
                ProductName = GetProductName();
                EditionId = GetEditionId();
                CurrentVersion = GetCurrentVersion();
                ReleaseId = GetReleaseId();
                CurrentBuildNumber = GetCurrentBuildNumber();
                BuildLab = GetBuildLab();
                OSName = GetOSName();
                OSVersionString = GetOSVersionString();
                OSVersion = GetOSVersion();
                OSArchitecture = GetOSArchitecture();
                OSServicePack = GetOSServicePack();
                OSMajorVersion = GetOSMajorVersion();
                OSMinorVersion = GetOSMinorVersion();
                OSMajorRevision = GetOSMajorRevision();
                OSMinorRevision = GetOSMinorRevision();
                OSBuild = GetOSBuild();
                ProcessArchitecture = GetProcessArchitecture();
            }
            catch (Exception)
            {
                throw new UnableToReadOSInformationException();
            }
        }
        /// <summary>
        /// Get the installed operating system.
        /// </summary>
        /// <returns>The installed OS. E.g.: Microsoft Windows 10 Enterprise - 64-Bit</returns>
        private static string GetOS()
		{
			string r = "";
			using (var searcher = new ManagementObjectSearcher("SELECT * FROM Win32_OperatingSystem"))
			{
				ManagementObjectCollection information = searcher.Get();
				if (information != null)
				{
					foreach (ManagementObject obj in information)
					{
						r = obj["Caption"].ToString() + " - " + obj["OSArchitecture"].ToString();
					}
				}
				r = r.Replace("NT 5.1.2600", "XP");
				r = r.Replace("NT 5.2.3790", "Server 2003");
			}
			return r;
		}

		/// <summary>
		/// Get the product name of the installed operating system.
		/// </summary>
		/// <returns>The product name. E.g.: Windows 10 Enterprise</returns>
		private static string GetProductName()
		{
			var regKey = Registry.LocalMachine;
			var subKey = regKey.OpenSubKey(@"SOFTWARE\Microsoft\Windows NT\CurrentVersion", false);
			return subKey.GetValue("ProductName").ToString();
		}

		/// <summary>
		/// Get the edition ID of the installed operating system.
		/// </summary>
		/// <returns>The edition ID. E.g.: Enterprise</returns>
		private static string GetEditionId()
		{
			var regKey = Registry.LocalMachine;
			var subKey = regKey.OpenSubKey(@"SOFTWARE\Microsoft\Windows NT\CurrentVersion", false);
			return subKey.GetValue("EditionID").ToString();
		}

		/// <summary>
		/// Get the current version of the installed operating system.
		/// </summary>
		/// <returns>The current version. E.g.: 6.3</returns>
		private static string GetCurrentVersion()
		{
			var regKey = Registry.LocalMachine;
			var subKey = regKey.OpenSubKey(@"SOFTWARE\Microsoft\Windows NT\CurrentVersion", false);
			return subKey.GetValue("CurrentVersion").ToString();
		}

		/// <summary>
		/// Get the current release ID of the installed operating system.
		/// </summary>
		/// <returns>The current release ID. E.g.: 1709</returns>
		private static string GetReleaseId()
		{
			var regKey = Registry.LocalMachine;
			var subKey = regKey.OpenSubKey(@"SOFTWARE\Microsoft\Windows NT\CurrentVersion", false);
			return subKey.GetValue("ReleaseId").ToString();
		}

		/// <summary>
		/// Get the current build number of the installed operating system.
		/// </summary>
		/// <returns>The current build number. E.g.: 16299</returns>
		private static string GetCurrentBuildNumber()
		{
			var regKey = Registry.LocalMachine;
			var subKey = regKey.OpenSubKey(@"SOFTWARE\Microsoft\Windows NT\CurrentVersion", false);
			return subKey.GetValue("CurrentBuildNumber").ToString();
		}

		/// <summary>
		/// Get the build lab of the installed operating system.
		/// </summary>
		/// </summary>
		/// <returns>The build lab. E.g.: 16299.431</returns>
		private static string GetBuildLab()
		{
			var regKey = Registry.LocalMachine;
			var subKey = regKey.OpenSubKey(@"SOFTWARE\Microsoft\Windows NT\CurrentVersion", false);
			string key = subKey.GetValue("BuildLabEx").ToString();

			string value = key.Remove(key.IndexOf(".") + 1);
			key = key.Remove(0, key.IndexOf(".") + 1);
			value = String.Concat(value, key.Remove(key.IndexOf(".")));

			return value;
		}

		/// <summary>
		/// Get the operating system name of the installed operating system.
		/// </summary>
		/// <returns>The OS name. E.g.: Microsoft Windows 10 Enterprise</returns>
		private static string GetOSName()
		{
			string r = "";
			using (var searcher = new ManagementObjectSearcher("SELECT * FROM Win32_OperatingSystem"))
			{
				ManagementObjectCollection information = searcher.Get();
				if (information != null)
				{
					foreach (ManagementObject obj in information)
					{
						r = obj["Caption"].ToString();
					}
				}
				r = r.Replace("NT 5.1.2600", "XP");
				r = r.Replace("NT 5.2.3790", "Server 2003");
			}
			return r;
		}

		/// <summary>
		/// Get the OS version string of the installed operating system.
		/// </summary>
		/// <returns>The OS version string. E.g.: Microsoft Windows NT 6.2.9200.0</returns>
		private static string GetOSVersionString()
		{
			return Environment.OSVersion.VersionString;
		}

		/// <summary>
		/// Get the OS version of the installed operating system.
		/// </summary>
		/// <returns>The OS version. E.g.: 6.2.9200.0</returns>
		private static string GetOSVersion()
		{
			return Environment.OSVersion.Version.ToString();
		}

		/// <summary>
		/// Get the OS architecture of the installed operating system.
		/// </summary>
		/// <returns>The OS architecture. E.g.: 64-Bit</returns>
		private static string GetOSArchitecture()
		{
			string r = "";
			using (var searcher = new ManagementObjectSearcher("SELECT * FROM Win32_OperatingSystem"))
			{
				ManagementObjectCollection information = searcher.Get();
				if (information != null)
				{
					foreach (ManagementObject obj in information)
					{
						r = obj["OSArchitecture"].ToString();
					}
				}
			}
			return r;
		}

		/// <summary>
		/// Get the OS service pack of the installed operating system.
		/// </summary>
		/// <returns>The OS service pack. E.g.: SP1</returns>
		private static string GetOSServicePack()
		{
			return Environment.OSVersion.ServicePack;
		}

		/// <summary>
		/// Get the OS major version of the installed operating system.
		/// </summary>
		/// <returns>The OS major version. E.g.: 6</returns>
		private static int GetOSMajorVersion()
		{
			Version ver = Environment.OSVersion.Version;
			return ver.Major;
		}

		/// <summary>
		/// Get the OS minor version of the installed operating system.
		/// </summary>
		/// <returns>The OS minor version. E.g.: 2</returns>
		private static int GetOSMinorVersion()
		{
			Version ver = Environment.OSVersion.Version;
			return ver.Minor;
		}

		/// <summary>
		/// Get the OS major revision of the installed operating system.
		/// </summary>
		/// <returns>The OS major revision. E.g.: 0</returns>
		private static int GetOSMajorRevision()
		{
			Version ver = Environment.OSVersion.Version;
			return ver.MajorRevision;
		}

		/// <summary>
		/// Get the OS minor revision of the installed operating system.
		/// </summary>
		/// <returns>The OS minor revision. E.g.: 0</returns>
		private static int GetOSMinorRevision()
		{
			Version ver = Environment.OSVersion.Version;
			return ver.MinorRevision;
		}

		/// <summary>
		/// Get the OS build of the installed operating system.
		/// </summary>
		/// <returns>The OS build. E.g.: 9200</returns>
		private static int GetOSBuild()
		{
			Version ver = Environment.OSVersion.Version;
			return ver.Build;
		}

		/// <summary>
		/// Get the process architecture of the installed operating system.
		/// </summary>
		/// <returns>The process architecture. E.g.: Win32NT</returns>
		private static string GetProcessArchitecture()
		{
			return Environment.OSVersion.Platform.ToString();
		}
		#endregion
	}

	#region Exceptions
	public class UnableToReadOSInformationException : ApplicationException
	{
		public UnableToReadOSInformationException()
		{ }

		public UnableToReadOSInformationException(string message) : base(message)
		{ }

		public UnableToReadOSInformationException(string message, Exception inner) : base(message, inner)
		{ }
	}

	public class UnknownErrorException : ApplicationException
	{
		public UnknownErrorException()
		{ }

		public UnknownErrorException(string message) : base(message)
		{ }

		public UnknownErrorException(string message, Exception inner) : base(message, inner)
		{ }
	}
	#endregion
}