using AircraftPlantContracts.BindingModels;
using AircraftPlantContracts.SearchModels;
using AircraftPlantContracts.StoragesContracts;
using AircraftPlantContracts.ViewModels;
using AircraftPlantFileImplement.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace AircraftPlantFileImplement.Implements
{
	/// <summary>
	/// Реализация интерфейса хранилища для писем
	/// </summary>
	public class MessageInfoStorage : IMessageInfoStorage
	{
		/// <summary>
		/// Хранилище
		/// </summary>
		private readonly DataFileSingleton _source;

		/// <summary>
		/// Конструктор
		/// </summary>
		public MessageInfoStorage()
		{
			_source = DataFileSingleton.GetInstance();
		}

		/// <summary>
		/// Получение полного списка
		/// </summary>
		/// <returns></returns>
		public List<MessageInfoViewModel> GetFullList()
		{
			return _source.Messages
				.Select(x => x.GetViewModel)
				.ToList();
		}

		/// <summary>
		/// Получение фильтрованного списка
		/// </summary>
		/// <param name="model"></param>
		/// <returns></returns>
		public List<MessageInfoViewModel> GetFilteredList(MessageInfoSearchModel model)
		{
			if (!model.ClientId.HasValue && (!model.PageSize.HasValue || !model.CurrentPage.HasValue))
			{
				return new();
			}

            if (model.CurrentPage.HasValue && model.PageSize.HasValue && model.ClientId.HasValue)
            {
                return _source.Messages
                    .Where(x => x.ClientId == model.ClientId)
                    .Skip((model.CurrentPage.Value - 1) * model.PageSize.Value)
                    .Take(model.PageSize.Value)
					.Select(x => x.GetViewModel)
					.ToList();
            }

            if (model.CurrentPage.HasValue && model.PageSize.HasValue)
            {
                return _source.Messages
                    .Skip((model.CurrentPage.Value - 1) * model.PageSize.Value)
                    .Take(model.PageSize.Value)
					.Select(x => x.GetViewModel)
					.ToList();
            }

            return _source.Messages
                .Where(x => x.ClientId == model.ClientId)
                .Select(x => x.GetViewModel)
                .ToList();
        }

		/// <summary>
		/// Получение элемента
		/// </summary>
		/// <param name="model"></param>
		/// <returns></returns>
		public MessageInfoViewModel? GetElement(MessageInfoSearchModel model)
		{
			if (string.IsNullOrEmpty(model.MessageId))
			{
				return null;
			}

			return _source.Messages
				.FirstOrDefault(x => x.MessageId == model.MessageId)
				?.GetViewModel;
		}

		/// <summary>
		/// Добавление элемента
		/// </summary>
		/// <param name="model"></param>
		/// <returns></returns>
		public MessageInfoViewModel? Insert(MessageInfoBindingModel model)
		{
			var newMessage = Message.Create(model);
			if (newMessage == null)
			{
				return null;
			}

			_source.Messages.Add(newMessage);
			_source.SaveMessages();
			return newMessage.GetViewModel;
		}

        /// <summary>
        /// Редактирование элемента
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        public MessageInfoViewModel? Update(MessageInfoBindingModel model)
        {
            var message = _source.Messages.FirstOrDefault(x => x.MessageId == model.MessageId);
            if (message == null)
            {
                return null;
            }

            message.Update(model);
            _source.SaveMessages();
            return message.GetViewModel;
        }
    }
}