using DinerContracts.BindingModels;
using DinerContracts.SearchModels;
using DinerContracts.StoragesContracts;
using DinerContracts.ViewModels;
using DinerFileImplement.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace DinerFileImplement.Implements {
	public class ImplementerStorage : IImplementerStorage {

		private readonly DataFileSingleton _source;

		private ImplementerStorage() {
			_source = DataFileSingleton.GetInstance();
		}

		public ImplementerViewModel? Insert(ImplementerBindingModel model) {
			model.ID = _source.Implementers.Count > 0 ? _source.Implementers.Max(x => x.ID) + 1 : 1;
			var newImplementer = Implementer.Create(model);
			if (newImplementer == null) {
				return null;
			}
			_source.Implementers.Add(newImplementer);
			_source.SaveImplementer();
			return newImplementer.GetViewModel;
		}

		public ImplementerViewModel? Update(ImplementerBindingModel model) {
			var implementer = _source.Implementers.FirstOrDefault(x => x.ID == model.ID);
			if (implementer == null) {
				return null;
			}
			implementer.Update(model);
			_source.SaveImplementer();
			return implementer.GetViewModel;
		}

		public ImplementerViewModel? Delete(ImplementerBindingModel model) {
			var element = _source.Implementers.FirstOrDefault(x => x.ID == model.ID);
            if ( element != null) {
				_source.Implementers.Remove(element);
				_source.SaveImplementer();
				return element.GetViewModel;
			}
			return null;
        }

		public ImplementerViewModel? GetElement(ImplementerSearchModel model) {
			if (string.IsNullOrEmpty(model.ImplementerFIO) && !model.ID.HasValue) {
				return null;
			}
			return _source.Implementers.FirstOrDefault(x => (!string.IsNullOrEmpty(model.ImplementerFIO) &&
															x.ImplementerFIO == model.ImplementerFIO) ||
															model.ID.HasValue && x.ID == model.ID)?.GetViewModel;
		}

		public List<ImplementerViewModel> GetFilteredList(ImplementerSearchModel model) {
			if (string.IsNullOrEmpty(model.ImplementerFIO)) {
				return new();
			}
			return _source.Implementers.Where(x => x.ImplementerFIO.Contains(model.ImplementerFIO))
										.Select(x => x.GetViewModel).ToList();
		}

		public List<ImplementerViewModel> GetFullList() {
			return _source.Implementers.Select(x => x.GetViewModel).ToList();
		}

		
	}
}