using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Windows.Forms;


namespace RobvanderWoude
{
	class SystemInformationWrapper
	{
		static string progver = "1.03";


		static int Main( string[] args )
		{
			#region Initialize Variables

			int rc = 0;
			int maxnamelength = 0;
			SortedList<string, string> requestedproperties = new SortedList<string, string>( );
			SortedList<string, string> propertynames = new SortedList<string, string>( );
			SortedList<string, int> propertyindices = new SortedList<string, int>( );
			bool ignoreinvalidproperties = false;
			bool listall = true;
			bool specificproperties = false;
			bool openurl = false;
			string url = "https://msdn.microsoft.com/library/system.windows.forms.systeminformation.aspx";

			#endregion Initialize Variables


			#region Parse Command Line

			if ( args.Length > 0 )
			{
				foreach ( string arg in args )
				{
					if ( arg == "/?" )
					{
						return ShowHelp( );
					}
					else if ( arg.ToUpper( ) == "/I" )
					{
						if ( ignoreinvalidproperties )
						{
							return ShowHelp( "Duplicate command line switch /I" );
						}
						ignoreinvalidproperties = true;
					}
					else if ( arg.ToUpper( ) == "/L" )
					{
						listall = true;
					}
					else if ( arg.ToUpper( ) == "/U" )
					{
						if ( openurl )
						{
							return ShowHelp( "Duplicate command line switch /U" );
						}
						openurl = true;
					}
					else if ( arg[0] == '/' )
					{
						return ShowHelp( "Invalid command line switch {0}", arg.ToUpper( ) );
					}
					else
					{
						requestedproperties.Add( arg.ToLower( ), arg );
						specificproperties = true;
						listall = false;
					}
				}
			}


			if ( listall && specificproperties )
			{
				return ShowHelp( "Either specificy one or more properties, or /L to list all, but not both" );
			}

			#endregion Parse Command Line


			#region Make a List of Available Properties

			int index = 0;
			foreach ( _PropertyInfo sp in typeof( SystemInformation ).GetProperties( ) )
			{
				propertynames.Add( sp.Name.ToLower( ), sp.Name );
				propertyindices.Add( sp.Name, index );
				if ( sp.Name.Length > maxnamelength )
				{
					maxnamelength = sp.Name.Length;
				}
				if ( !listall )
				{
					if ( requestedproperties.Keys.Contains( sp.Name.ToLower( ) ) )
					{
						requestedproperties[sp.Name.ToLower( )] = sp.Name;
					}
					// Translate requested indices to property names
					if ( requestedproperties.Keys.Contains( index.ToString( ) ) )
					{
						requestedproperties[sp.Name.ToLower( )] = sp.Name;
						requestedproperties.Remove( index.ToString( ) );
					}
				}
				index += 1;
			}

			#endregion Make a List of Available Properties


			if ( listall )
			{
				// Default: list all properties and their values
				// Show table head
				Console.WriteLine( "{0,-" + maxnamelength + "}    Index:      Value:", "Property Name:" );
				Console.WriteLine( "{0,-" + maxnamelength + "}    ======      ======", "==============" );
				foreach ( string property in propertynames.Values )
				{
					object propval = typeof( SystemInformation ).GetProperty( property ).GetValue( typeof( SystemInformation ), null );
					string propertyvalue = propval.ToString( );
					// PowerStatus has to be handled separately, by default it only returns a string "System.Windows.Forms.PowerStatus"
					if ( property == "PowerStatus" )
					{
						propertyvalue = GetPowerStatus( );
					}
					Console.WriteLine( "{0,-" + maxnamelength + "}    {1,6}      {2}", property, propertyindices[property], propertyvalue );
				}
			}
			else
			{
				foreach ( string requestedproperty in requestedproperties.Keys )
				{
					if ( propertynames.Keys.Contains( requestedproperty ) )
					{
						// Get the selected property's value
						string propertyvalue = Convert.ToString( typeof( SystemInformation ).GetProperty( requestedproperties[requestedproperty] ).GetValue( typeof( SystemInformation ), null ) );
						// PowerStatus has to be handled separately, by default it only returns a string "System.Windows.Forms.PowerStatus"
						if ( requestedproperties[requestedproperty] == "PowerStatus" )
						{
							propertyvalue = GetPowerStatus( );
						}
						// Try if the return value can be set to the selected property's value
						try
						{
							rc = Convert.ToInt32( propertyvalue );
						}
						catch ( Exception )
						{
							rc = 0;
						}
						// Display selected property and its value
						Console.WriteLine( "{0}={1}", requestedproperties[requestedproperty], propertyvalue );
					}
					else if ( !ignoreinvalidproperties )
					{
						return ShowHelp( "Invalid property \"{0}\"", requestedproperty );
					}
				}


				if ( requestedproperties.Count > 1 )
				{
					rc = 0;
				}
			}


			// Open the URL with the list of available properties
			if ( openurl )
			{
				Process process = new Process( );
				process.StartInfo = new ProcessStartInfo( url );
				process.Start( );
			}


			return rc;
		}


		static string GetPowerStatus( )
		{
			string powerstatus = String.Empty;
			object propval = typeof( SystemInformation ).GetProperty( "PowerStatus" ).GetValue( typeof( SystemInformation ), null );
			string bcs = typeof( PowerStatus ).GetProperty( "BatteryChargeStatus" ).GetValue( propval, null ).ToString( );
			string bfl = typeof( PowerStatus ).GetProperty( "BatteryFullLifetime" ).GetValue( propval, null ).ToString( );
			string blp = ( Convert.ToInt32( typeof( PowerStatus ).GetProperty( "BatteryLifePercent" ).GetValue( propval, null ) ) * 100 ).ToString( ) + "%";
			string blr = typeof( PowerStatus ).GetProperty( "BatteryLifeRemaining" ).GetValue( propval, null ).ToString( );
			string pls = typeof( PowerStatus ).GetProperty( "PowerLineStatus" ).GetValue( propval, null ).ToString( );
			powerstatus = String.Format( "{{BatteryChargeStatus={0}", bcs );
			powerstatus += String.Format( ", BatteryFullLifetime={0}", ( bfl == "-1" ? "Unknown" : bfl ) );
			powerstatus += String.Format( ", BatteryLifePercent={0}", blp );
			powerstatus += String.Format( ", BatteryLifeRemaining={0}", ( blr == "-1" ? "Unknown" : blr ) );
			powerstatus += String.Format( ", PowerLineStatus={0}}}", pls );
			return powerstatus;
		}


		static int ShowHelp( params string[] errmsg )
		{
			#region Error Message

			if ( errmsg.Length > 0 )
			{
				List<string> errargs = new List<string>( errmsg );
				errargs.RemoveAt( 0 );
				Console.Error.WriteLine( );
				Console.ForegroundColor = ConsoleColor.Red;
				Console.Error.Write( "ERROR:\t" );
				Console.ForegroundColor = ConsoleColor.White;
				Console.Error.WriteLine( errmsg[0], errargs.ToArray( ) );
				Console.ResetColor( );
			}

			#endregion Error Message


			#region Help Text

			/*
			SystemInformation.exe,  Version 1.03
			Wrapper for the .NET SystemInformation class
			
			Usage:   SystemInformation  [ property [ property [..] ] | /L ]  [ /I ]  [ /U ]
			
			Where:   property   name or index of a SystemInformation property to be tested
			                    (multiple properties allowed, default: list all)
			         /I         Ignore and skip invalid property names specified on the
			                    command line (default: abort on invalid property name)
			         /L         List each property name and its index and value, sorted by
			                    name (default, implemented for backwards compatibility)
			         /U         open URL with list of properties and their meanings
			
			Notes:   If a single property value is requested, the return code will equal
			         the value returned by the function if it is numerical, or 0 if not.
			         If multiple properties and their values are listed, return code is 0.
			         In case of (command line) errors the return code will be -1.
			         Be careful with the /I switch when requesting multiple properties,
			         as you will be unable to determine which particular one is ignored.
			         The meaning of the returned values can be found at
			         msdn.microsoft.com/library/system.windows.forms.systeminformation.aspx
			
			Written by Rob van der Woude
			http://www.robvanderwoude.com
			*/

			Console.Error.WriteLine( );

			Console.Error.WriteLine( "SystemInformation.exe,  Version {0}", progver );

			Console.Error.WriteLine( "Wrapper for the .NET SystemInformation class" );

			Console.Error.WriteLine( );

			Console.Error.Write( "Usage:   " );
			Console.ForegroundColor = ConsoleColor.White;
			Console.Error.WriteLine( "SystemInformation  [ property [ property [..] ] | /L ]  [ /I ]  [ /U ]" );
			Console.ResetColor( );

			Console.Error.WriteLine( );

			Console.Error.Write( "Where:   " );
			Console.ForegroundColor = ConsoleColor.White;
			Console.Error.Write( "property" );
			Console.ResetColor( );
			Console.Error.WriteLine( "   name or index of a SystemInformation property to be tested" );

			Console.Error.WriteLine( "                    (multiple properties allowed, default: list all)" );

			Console.ForegroundColor = ConsoleColor.White;
			Console.Error.Write( "         /I         I" );
			Console.ResetColor( );
			Console.Error.WriteLine( "gnore and skip invalid property names specified on the" );

			Console.Error.WriteLine( "                    command line (default: abort on invalid property name)" );

			Console.ForegroundColor = ConsoleColor.White;
			Console.Error.Write( "         /L         L" );
			Console.ResetColor( );
			Console.Error.WriteLine( "ist each property name and its index and value, sorted by" );

			Console.Error.WriteLine( "                    name (default, implemented for backwards compatibility)" );

			Console.ForegroundColor = ConsoleColor.White;
			Console.Error.Write( "         /U" );
			Console.ResetColor( );
			Console.Error.Write( "         open " );
			Console.ForegroundColor = ConsoleColor.White;
			Console.Error.Write( "U" );
			Console.ResetColor( );
			Console.Error.WriteLine( "RL with list of properties and their meanings" );

			Console.Error.WriteLine( );

			Console.Error.WriteLine( "Notes:   If a single property value is requested, the return code will equal" );

			Console.Error.WriteLine( "         the value returned by the function if it is numerical, or 0 if not." );

			Console.Error.WriteLine( "         If multiple properties and their values are listed, return code is 0." );

			Console.Error.WriteLine( "         In case of (command line) errors the return code will be -1." );

			Console.Error.WriteLine( "         Be careful with the /I switch when requesting multiple properties," );

			Console.Error.WriteLine( "         as you will be unable to determine which particular one is ignored." );

			Console.Error.WriteLine( "         The meaning of the returned values can be found online at" );

			Console.ForegroundColor = ConsoleColor.DarkGray;
			Console.Error.WriteLine( "         msdn.microsoft.com/library/system.windows.forms.systeminformation.aspx" );
			Console.ResetColor( );

			Console.Error.WriteLine( );

			Console.Error.WriteLine( "Written by Rob van der Woude" );

			Console.Error.WriteLine( "http://www.robvanderwoude.com" );

			#endregion Help Text


			return -1;
		}
	}
}