using IStation.Epanet.Enums;
using System;

namespace IStation.Epanet
{

    ///<summary>Epanet exception codes handler.</summary>
    public class EnException : Exception
    {

        ///<summary>Array of arguments to be used in the error string creation.</summary>
        private readonly object[] _arguments;

        ///<summary>Epanet error code.</summary>
        protected readonly ErrorCode _code;

        /// <summary>Get error code.</summary>
        /// <value>Code id.</value>
        public ErrorCode Code => _code;

        ///<summary>Constructor from error code id.</summary>
        ///<param name="code">Error code id.</param>

        public EnException(ErrorCode code)
        {
            _arguments = null;
            _code = code;
        }

        /// <summary>Constructor from error code id and multiple arguments.</summary>
        ///  <param name="code">Error code id.</param>
        /// <param name="arg">Extra arguments.</param>
        ///  
        public EnException(ErrorCode code, params object[] arg)
        {
            _code = code;
            _arguments = arg;
        }

        /// <summary>Constructor from error code id and inner exception.</summary>
        ///  <param name="code">Error code id.</param>
        /// <param name="innerException"></param>
        ///  
        public EnException(ErrorCode code, Exception innerException)
            : base(null, innerException)
        {
            _code = code;
        }

        ///<summary>Handles the exception string conversion.</summary>
        /// <returns>Final error string.</returns>
        public override string Message
        {
            get
            {
                string format;

                try
                {
                    format = _code.GetMsg();
                }
                catch (Exception)
                {
                    format = null;
                }


                if (format == null)
                    return string.Format("Unknown error message ({0})", _code);

                return _arguments != null ? string.Format(format, _arguments) : format;
            }
        }
    }

}