using System;
using System.Collections;
using System.Collections.Generic;
using Kreta.Core.Enum;
using Kreta.Core.Exceptions;
using Kreta.Ellenorzo.Domain.VN.Interfaces;

namespace Kreta.Ellenorzo.Domain.VN.Indexers
{
    /// <summary>
    /// Author: Kovács Kornél (DevKornél) Created On: 2019.07.
    /// </summary>
    public class UidsCollection<T> : IEnumerable<T> where T : class, IReadonlyUidRaw
    {
        private readonly List<T> _uids = new List<T>();

        public UidsCollection(string uidsRaw, Converter<string[], T> uidsConverter)
        {
            if (string.IsNullOrWhiteSpace(uidsRaw))
            {
                return;
            }

            string[] uidArray = uidsRaw.Split(Constant.UidDelimiter);

            if (uidArray.Length > 50)
            {
                throw new BlException(BlExceptionType.ListaTobbMint50ElemetTartalmaz);
            }

            _uids = new List<T>(uidArray.Length);

            for (int i = 0; i < uidArray.Length; i++)
            {
                _uids.Add(GetUid(uidArray[i]));
            }

            T GetUid(string uidRaw)
            {
                string[] compositeKey = uidRaw.Split(Constant.UidInnerDelimiter);

                T uid = uidsConverter.Invoke(compositeKey);
                return uid;
            }
        }

        public T this[int index] => _uids[index];

        public IEnumerator GetEnumerator() => throw new NotImplementedException();

        IEnumerator<T> IEnumerable<T>.GetEnumerator() => _uids.GetEnumerator();
    }
}