using System;
using System.IO;
using System.Linq;


namespace RobvanderWoude
{
	internal class URLEscape
	{
		static readonly string progver = "1.00";


		static int Main( string[] args )
		{
			int rc = 0;

			int argumentscount = args.Length;
			if ( Console.IsInputRedirected )
			{
				argumentscount++;
			}
			if ( argumentscount != 1 || args.Contains( "/?" ) )
			{
				return ShowHelp( );
			}

			string unescapedurl = string.Empty;
			if ( Console.IsInputRedirected )
			{
				unescapedurl = Console.In.ReadToEnd( );
			}
			else if ( File.Exists( args[0] ) )
			{
				unescapedurl = File.ReadAllText( args[0] );
			}
			else
			{
				unescapedurl = args[0];
			}
			// NOTE: WebUtility.UrlEncode is not used here because it also escapes colons and forward slashes
			string escapedurl = new Uri( unescapedurl ).AbsoluteUri.ToString( ); // does not escape parentheses
			escapedurl = escapedurl.Replace( "(", "%28" ).Replace( ")", "%29" ); // escape parentheses as well
			Console.Write( escapedurl );


			return rc;
		}

		public static int ShowHelp( string errorMessage = "" )
		{
			#region Help Text

			/*
			URLEscape,  Version 1.00
			Display URL-escaped input string in console
 
			Usage:  URLESCAPE  textfile
 
			   or:  URLESCAPE  unescapedurl
 
			   or:  some_program | URLESCAPE
 
			Where:  textfile       file containing text to be escaped
			        unescapedurl   string to be escaped
			        some_program   program whose output is to be escaped
 
			Note:   Exit code ("errorlevel") -1 in case of errors, otherwise 0.
	
			Written by Rob van der Woude
			https://www.robvanderwoude.com
			*/

			#endregion Help Text


			#region Error Message

			if ( !string.IsNullOrWhiteSpace( errorMessage ) )
			{
				Console.Error.WriteLine( );
				Console.ForegroundColor = ConsoleColor.Red;
				Console.Error.Write( "ERROR: " );
				Console.ForegroundColor = ConsoleColor.White;
				Console.Error.WriteLine( errorMessage );
				Console.ResetColor( );
			}

			#endregion Error Message


			#region Display Help

			Console.Error.WriteLine( );

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

			Console.Error.WriteLine( "Display URL-escaped input string in console" );

			Console.Error.WriteLine( );

			Console.Error.Write( "Usage:  " );
			Console.ForegroundColor = ConsoleColor.White;
			Console.Error.WriteLine( "URLESCAPE  textfile" );
			Console.ResetColor( );

			Console.Error.WriteLine( );

			Console.Error.Write( "   or:  " );
			Console.ForegroundColor = ConsoleColor.White;
			Console.Error.WriteLine( "URLESCAPE  unescapedurl" );
			Console.ResetColor( );

			Console.Error.WriteLine( );

			Console.Error.Write( "   or:  " );
			Console.ForegroundColor = ConsoleColor.White;
			Console.Error.WriteLine( "some_program | URLESCAPE" );
			Console.ResetColor( );

			Console.Error.WriteLine( );

			Console.Error.Write( "Where:  " );
			Console.ForegroundColor = ConsoleColor.White;
			Console.Error.Write( "textfile" );
			Console.ResetColor( );
			Console.Error.WriteLine( "       file containing text to be escaped" );

			Console.ForegroundColor = ConsoleColor.White;
			Console.Error.Write( "        unescapedurl" );
			Console.ResetColor( );
			Console.Error.WriteLine( "   string to be escaped" );

			Console.ForegroundColor = ConsoleColor.White;
			Console.Error.Write( "        some_program" );
			Console.ResetColor( );
			Console.Error.WriteLine( "   program whose output is to be escaped" );

			Console.Error.WriteLine( );

			Console.Error.WriteLine( "Note:   Exit code (\"errorlevel\") -1 in case of errors, otherwise 0." );

			Console.Error.WriteLine( );

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

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

			#endregion Display Help


			return -1;
		}
	}
}