using ConfectioneryContracts.BindingModels;
using ConfectioneryContracts.BusinessLogicsContracts;
using ConfectioneryContracts.SearchModels;
using ConfectioneryContracts.StoragesContracts;
using ConfectioneryContracts.ViewModels;
using ConfectioneryDataModels.Enums;
using ConfectioneryDataModels.Models;
using Microsoft.Extensions.Logging;
namespace ConfectioneryBusinessLogic.BusinessLogics
{
    public class OrderLogic : IOrderLogic
    {
        private readonly ILogger _logger;
        private readonly IOrderStorage _orderStorage;
		private readonly IShopStorage _shopStorage;
		private readonly IShopLogic _shopLogic;
		private readonly IPastryStorage _pastryStorage;
		public OrderLogic(ILogger<OrderLogic> logger, 
            IOrderStorage orderStorage, IShopStorage shopStorage,
			IShopLogic shopLogic, IPastryStorage pastryStorage)
        {
            _logger = logger;
            _orderStorage = orderStorage;
			_shopStorage = shopStorage;
			_shopLogic = shopLogic;
			_pastryStorage = pastryStorage;
		}
        public List<OrderViewModel>? ReadList(OrderSearchModel? model)
        {
            _logger.LogInformation("ReadList. Id:{ Id}", model?.Id);
            var list = model == null ? _orderStorage.GetFullList() : 
                _orderStorage.GetFilteredList(model);
            if (list == null)
            {
                _logger.LogWarning("ReadList return null list");
                return null;
            }
            _logger.LogInformation("ReadList. Count:{Count}", list.Count);
            return list;
        }
        public bool CreateOrder(OrderBindingModel model)
        {
            CheckModel(model);
            if (model.Status != OrderStatus.Неизвестен) return false;
            model.Status = OrderStatus.Принят;
            if (_orderStorage.Insert(model) == null)
            {
                _logger.LogWarning("Insert operation failed");
                return false;
            }
            return true;
        }
		private bool ChangeStatus(OrderBindingModel model, OrderStatus status)
        {
            CheckModel(model);
            var element = _orderStorage.GetElement(
                new OrderSearchModel { Id = model.Id });
            if (element == null)
            {
                _logger.LogWarning("Read operation failed");
                return false;
            }
            if (element.Status != status - 1)
            {
                _logger.LogWarning("Status change operation failed");
                throw new InvalidOperationException("Текущий статус заказа" +
                    " не может быть переведен в выбранный");
            }
			if (element.Status == OrderStatus.Готов)
			{
				var pastry = _pastryStorage.GetElement(new PastrySearchModel() 
                { Id = model.PastryId });
				if (pastry == null)
				{
					_logger.LogWarning("Status update to " + 
                        status.ToString() + 
                        " operation failed. Document not found.");
					return false;
				}
				if (CheckSupply(pastry, model.Count) == false)
				{
					_logger.LogWarning("Status update to " + 
                        status.ToString() + 
                        " operation failed. Shop supply error.");
					return false;
				}
			}
			model.Status = status;
            if (model.Status == OrderStatus.Выдан) 
                model.DateImplement = DateTime.Now;
            _orderStorage.Update(model);
            return true;
        }
        public bool TakeOrderInWork(OrderBindingModel model)
        {
            return ChangeStatus(model, OrderStatus.Выполняется);
        }
        public bool FinishOrder(OrderBindingModel model)
        {
            return ChangeStatus(model, OrderStatus.Готов);
        }
        public bool DeliveryOrder(OrderBindingModel model)
        {
            return ChangeStatus(model, OrderStatus.Выдан);
        }
        private void CheckModel(OrderBindingModel model, 
            bool withParams = true)
        {
            if (model == null)
            {
                throw new ArgumentNullException(nameof(model));
            }
            if (!withParams)
            {
                return;
            }
            if (model.Sum <= 0)
            {
                throw new ArgumentNullException(
                    "Цена заказа должна быть больше 0", nameof(model.Sum));
            }
            if (model.Count <= 0)
            {
                throw new ArgumentNullException(
                    "Количество элементов в заказе должно быть больше 0", 
                    nameof(model.Count));
            }
            _logger.LogInformation("Order. Sum:{ Cost}. Id: { Id}",
                model.Sum, model.Id);
        }
		private bool CheckSupply(IPastryModel Pastry, int count)
		{
			if (count <= 0)
			{
				_logger.LogWarning(
                    "Check then supply operation error. Pastry count < 0.");
				return false;
			}

			int sumCapacity = 0;
			int sumCount = 0;
			sumCapacity = _shopStorage.GetFullList()
                .Select(x => x.MaxCapacity).Sum();
			sumCount = _shopStorage.GetFullList()
                .Select(x => x.ShopPastries
                .Select(y => y.Value.Item2).Sum()).Sum();
			int freeSpace = sumCapacity - sumCount;

			if (freeSpace - count < 0)
			{
				_logger.LogWarning("Check then supply operation error. " +
                    "There's no place for new Pastry in shops.");
				return false;
			}

			foreach (var shop in _shopStorage.GetFullList())
			{
				freeSpace = shop.MaxCapacity;
				foreach (var doc in shop.ShopPastries)
				{
					freeSpace -= doc.Value.Item2;
				}
				if (freeSpace == 0)
				{
					continue;
				}
				if (freeSpace - count >= 0)
				{
					if (_shopLogic.MakeSupply(new() { Id = shop.Id }, 
                        Pastry, count))
						count = 0;
					else
					{
						_logger.LogWarning("Supply error");
						return false;
					}
				}
				if (freeSpace - count < 0)
				{
					if (_shopLogic.MakeSupply(new() { Id = shop.Id }, 
                        Pastry, freeSpace))
						count -= freeSpace;
					else
					{
						_logger.LogWarning("Supply error");
						return false;
					}
				}
				if (count <= 0)
				{
					return true;
				}
			}
			return false;
		}
	}
}