using FlowerShopContracts.BindingModels;
using FlowerShopContracts.BusinessLogicsContracts;
using FlowerShopContracts.SearchModels;
using FlowerShopContracts.StoragesContracts;
using FlowerShopContracts.ViewModels;
using FlowerShopDataModels.Enums;
using FlowerShopDataModels.Models;
using Microsoft.Extensions.Logging;

namespace FlowerShopBusinessLogic.BusinessLogics
{
    public class OrderLogic : IOrderLogic
    {
        private readonly ILogger _logger;
        private readonly IOrderStorage _orderStorage;
        private readonly IFlowerStorage _flowerStorage;
		private readonly IShopStorage _shopStorage;
        private readonly IShopLogic _shopLogic;
		public OrderLogic(ILogger<OrderLogic> logger, IOrderStorage orderStorage, IFlowerStorage flowerStorage, IShopStorage shopStorage, IShopLogic shopLogic)
        {
            _logger = logger;
            _orderStorage = orderStorage;
            _flowerStorage = flowerStorage;
            _shopStorage = shopStorage;
            _shopLogic = shopLogic;
        }
        public List<OrderViewModel>? ReadList(OrderSearchModel? model)
        {
            _logger.LogInformation("ReadList/ OrderId:{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)
            {
                model.Status = OrderStatus.Неизвестен;
                _logger.LogWarning("Insert operation failed");
                return false;
            }
            return true;
        }
        public bool TakeOrderInWork(OrderBindingModel model)
        {
            return ToNextStatus(model, OrderStatus.Выполняется);
        }
        public bool FinishOrder(OrderBindingModel model)
        {
            return ToNextStatus(model, OrderStatus.Готов);
        }
        public bool DeliveryOrder(OrderBindingModel model)
        {
            return ToNextStatus(model, OrderStatus.Выдан);
        }

        public bool ToNextStatus(OrderBindingModel model, OrderStatus orderStatus)
        {
            CheckModel(model, false);
            var element = _orderStorage.GetElement(new OrderSearchModel()
            {
                Id = model.Id
            });
            if (element == null)
            {
                throw new ArgumentNullException(nameof(element));
            }

            model.FlowerId = element.FlowerId;
            model.DateCreate = element.DateCreate;
            model.DateImplement = element.DateImplement;
            model.Status = element.Status;
            model.Count = element.Count;
            model.Sum = element.Sum;

            if (model.Status != orderStatus - 1)
            {
                _logger.LogWarning("Status update to " + orderStatus + " operation failed");
                return false;
            }
            if (orderStatus == OrderStatus.Выдан)
            {
                var flower = _flowerStorage.GetElement(new FlowerSearchModel() { Id = model.FlowerId } );
                if (flower == null)
                {
                    return false;
                }
                if (!SupplyFlowers(flower, model.Count))
                {
					_logger.LogWarning("Change status operation failed. Flowers delivery operation failed");
					return false;
				}
            }
            model.Status = orderStatus;
            if (model.Status == OrderStatus.Готов)
            {
                model.DateImplement = DateTime.Now;
            }
            else
            {
                model.DateImplement = element.DateImplement;
            }
            if (_orderStorage.Update(model) == null)
            {
                model.Status--;
                _logger.LogWarning("Changing status operation failed");
                return false;
            }
            return true;
        }
        private void CheckModel(OrderBindingModel model, bool withParams = true)
        {
            if (model == null)
            {
                throw new ArgumentNullException(nameof(model));
            }
            if (!withParams)
            {
                return;
            }
            if (model.Count <= 0)
            {
                throw new ArgumentNullException("Количество цветов должно быть больше 0", nameof(model.Count));
            }
            if (model.Sum <= 0)
            {
                throw new ArgumentNullException("Цена заказа должна быть больше 0", nameof(model.Sum));
            }
            if (model.DateImplement.HasValue && model.DateImplement < model.DateCreate)
            {
                throw new ArithmeticException($"Дата выдачи заказа {model.DateImplement} должна быть позже даты его создания {model.DateCreate}");
            }
            _logger.LogInformation("Order. FlowerId:{EngineId}.Count:{Count}.Sum:{Sum}Id:{Id}", model.FlowerId, model.Count, model.Sum, model.Id);
        }

        private bool SupplyFlowers(IFlowerModel flower, int count)
        {
            if (count < 0)
            {
				_logger.LogWarning("Flower supply operation failed. Count <= 0");
				return false;
			}
            var shopList = _shopStorage.GetFullList();
            var shopsCapacity = shopList.Sum(x => x.MaximumFlowers);
            int currentFlowers = shopList.Select(x => x.ShopFlowers.Sum(y => y.Value.Item2)).Sum();
            int freeSpace = shopsCapacity - currentFlowers;

            if (freeSpace < count)
            {
				_logger.LogWarning("Flower supply operation failed. No free space for new flowers");
				return false;
            }

            foreach (var shop in shopList) 
            {
                freeSpace = shop.MaximumFlowers - shop.ShopFlowers.Sum(x => x.Value.Item2);
                if (freeSpace == 0)
                {
                    continue;
                }
                if (freeSpace >= count) 
                {
                    if (_shopLogic.MakeSupply(new ShopSearchModel() { Id = shop.Id }, flower, count))
                    {
                        count = 0;
                    }
					else
					{
						_logger.LogWarning("Flowers delivery operation failed");
						return false;
					}
				}
                else
                {
					if (_shopLogic.MakeSupply(new ShopSearchModel() { Id = shop.Id }, flower, freeSpace))
					{
						count -= freeSpace;
					}
					else
					{
						_logger.LogWarning("Flowers delivery operation failed");
						return false;
					}
				}
                if (count == 0)
                {
                    return true;
                }
            }
			return false;
		}
    }
}