using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using XYLEM.Base;

namespace XYLEM.Communication.ValueEncoders {
	/// <summary>
	/// IP Address encoder when it has to be converted to a u32 value
	/// </summary>
	internal static class U32_IP_Encoder {
		/// <summary>
		/// Check if string is okay and possible to encode
		/// </summary>
		/// <param name="stringForCheck"></param>
		/// <returns></returns>
		internal static bool IsOkay(string stringForCheck) {
			try {
				if (string.IsNullOrEmpty( stringForCheck )) {
					return false; // if string empty, then this is off and there is nothing to check 
				}
				try {
					var test = Encode( stringForCheck );
				} catch { 
					return false; // Error is not possible to convert
				}
				return true; // Okay to convert
			} catch (Exception ex) {
				throw new Exception( ex.ToFuncErrorText( typeof( U32_IP_Encoder ).ToString( ), "IsOkay" ) );
			}
		}

		/// <summary>
		/// Encode xxx.xxx.xxx.xxx to bytes
		/// </summary>
		/// <param name="ip_XXX_XXX_XXX_XXX"></param>
		/// <returns></returns>
		static internal byte[] Encode(string ip_XXX_XXX_XXX_XXX) {
			try {
				var splited = ip_XXX_XXX_XXX_XXX.Split( '.' );
				if (splited.Count( ) != 4) {
					throw new Exception( "IP must be formated xxx.xxx.xxx.xxx but is " + ip_XXX_XXX_XXX_XXX.ToString( ) );
				}
				var values = splited.Select( value => byte.Parse( value ) );
				return values.ToArray( );
			} catch (Exception ex) {
				throw new Exception( ex.ToFuncErrorText( typeof( U32_IP_Encoder ).ToString( ), "Encode" ) );
			}
		}

		/// <summary>
		/// decode bytes
		/// </summary>
		/// <param name="data"></param>
		/// <returns>xxx.xxx.xxx.xxx</returns>
		static internal string Decode(byte[] data) {
			try {
				if ((data == null) || (data.Count( ) != 4)) {
					throw new Exception( "Must be 4 bytes" );
				}
				return String.Format( "{0}.{1}.{2}.{3}", data[ 0 ], data[ 1 ], data[ 2 ], data[ 3 ] );
			} catch (Exception ex) {
				throw new Exception( ex.ToFuncErrorText( typeof( U32_IP_Encoder ).ToString( ), "Decode" ) );
			}
		}

	}
}