PIbd-23_Mochalov_D.V._LawFirm/LawFirm/LawFirmFileImplement/Implements/MessageInfoStorage.cs

using LawFirmContracts.BindingModels;
using LawFirmContracts.SearchModels;
using LawFirmContracts.StorageContracts;
using LawFirmContracts.ViewModels;
using LawFirmFileImplement.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace LawFirmFileImplement.Implements
{
	public class MessageInfoStorage : IMessageInfoStorage
	{
		private readonly DataFileSingleton _source;
		public MessageInfoStorage()
		{
			_source = DataFileSingleton.GetInstance();
		}

		public MessageInfoViewModel? GetElement(MessageInfoSearchModel model)
		{
			if (model.MessageId != null)
			{
				return _source.Messages.FirstOrDefault(x => x.MessageId == model.MessageId)?.GetViewModel;
			}
			return null;
		}

		public List<MessageInfoViewModel> GetFilteredList(MessageInfoSearchModel model)
		{
			var messages = _source.Messages
				.Where(x => x.ClientId == model.ClientId)
				.Select(x => x.GetViewModel);

			if (!(model.Page.HasValue && model.PageSize.HasValue))
			{
				return messages.ToList();
			}
			return messages.Skip((model.Page.Value - 1) * model.PageSize.Value).Take(model.PageSize.Value).ToList();
		}

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

		public MessageInfoViewModel? Insert(MessageInfoBindingModel model)
		{
			var newMessage = MessageInfo.Create(model);
			if (newMessage == null)
			{
				return null;
			}
			_source.Messages.Add(newMessage);
			_source.SaveMessages();
			return newMessage.GetViewModel;
		}

        public MessageInfoViewModel? Update(MessageInfoBindingModel model)
        {
            var message = _source.Messages.FirstOrDefault(x => x.MessageId.Equals(model.MessageId));
            if (message != null)
            {
                message.Update(model);
                _source.SaveMessages();
            }
            return message?.GetViewModel;
        }
    }
}