using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Microsoft.Extensions.Logging;
using IceCreamShopContracts.BindingModels;
using IceCreamShopContracts.BusinessLogicsContracts;
using IceCreamShopContracts.SearchModels;
using IceCreamShopContracts.StoragesContracts;
using IceCreamShopContracts.ViewModels;
using AbstractIceCreamShopDataModels.Enums;
using IceCreamBusinessLogic.MailWorker;
using AbstractIceCreamShopDataModels.Models;

namespace IceCreamBusinessLogic.BusinessLogics
{
    public class OrderLogic : IOrderLogic
    {
        private readonly ILogger _logger;
        private readonly IOrderStorage _orderStorage;
		private readonly AbstractMailWorker _mailWorker;
		private readonly IClientLogic _clientLogic;
        private readonly IShopStorage _shopStorage;
        private readonly IShopLogic _shopLogic;
        private readonly IIceCreamStorage _iceCreamStorage;

		public OrderLogic(ILogger<OrderLogic> logger, IOrderStorage orderStorage, AbstractMailWorker mailWorker, IClientLogic clientLogic)
		{
        public OrderLogic(IOrderStorage orderStorage, IShopStorage shopStorage, IShopLogic shopLogic, IIceCreamStorage iceCreamStorage, ILogger<OrderLogic> logger)
        {
            _orderStorage = orderStorage;
            _shopStorage = shopStorage;
            _logger = logger;
			_mailWorker = mailWorker;
			_clientLogic = clientLogic;
		}
            _shopLogic = shopLogic;
            _iceCreamStorage = iceCreamStorage;
        }

        public bool CreateOrder(OrderBindingModel model)
        {
            CheckModel(model);
            if(model.Status != OrderStatus.Неизвестен)
            {
                _logger.LogWarning("Insert operation failed. Order status incorrect.");
                return false;
            }
            model.Status = OrderStatus.Принят;
			var result = _orderStorage.Insert(model);
			if (result == null)
			{
				_logger.LogWarning("Insert operation failed");
				return false;
			}
			SendOrderStatusMail(result.ClientId, $"Новый заказ создан. Номер заказа #{result.Id}", $"Заказ #{result.Id} от {result.DateCreate} на сумму {result.Sum:0.00} принят");
			return true;
		}

        public bool DeliveryOrder(OrderBindingModel model)
        {
            return SetNewStatus(model, OrderStatus.Готов);
        }

        public bool FinishOrder(OrderBindingModel model)
        {
            return SetNewStatus(model, OrderStatus.Выдан);
        }

        public bool TakeOrderInWork(OrderBindingModel model)
        {
            return SetNewStatus(model, OrderStatus.Выполняется);
        }

        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;
        }

        private void CheckModel(OrderBindingModel model)
        {
            if (model == null)
            {
                throw new ArgumentNullException(nameof(model));
            }
            if (model.Id < 0)
            {
                throw new ArgumentNullException("Некорректный идентификатор заказа", nameof(model.Id));
            }
            if (model.IceCreamId < 0)
            {
                throw new ArgumentNullException("Некорректный идентификатор мороженого", nameof(model.IceCreamId));
            }
            if (model.Count <= 0)
            {
                throw new ArgumentNullException("Количество мороженого в заказе должно быть больше 0", nameof(model.Count));
            }
            if (model.Sum <= 0)
            {
                throw new ArgumentNullException("Сумма заказа должна быть больше 0", nameof(model.Sum));
            }
            _logger.LogInformation("Order. OrderID:{Id}.Sum:{ Sum}. DocumentId: { DocumentId}", model.Id, model.Sum, model.IceCreamId);
        }

        public bool SetNewStatus(OrderBindingModel rawModel, OrderStatus newStatus)
        {
            var viewModel = _orderStorage.GetElement(new OrderSearchModel
            {
                Id = rawModel.Id
            });

            if (viewModel == null)
            {
                _logger.LogWarning("Order model not found");
                return false;
            }

            OrderBindingModel model = new OrderBindingModel
            {
                Id = viewModel.Id,
                IceCreamId = viewModel.IceCreamId,
                Status = viewModel.Status,
                DateCreate = viewModel.DateCreate,
                DateImplement = viewModel.DateImplement,
                Count = viewModel.Count,
                Sum = viewModel.Sum,
                ImplementerId = viewModel.ImplementerId
            };
            if (rawModel.ImplementerId.HasValue)
            {
                model.ImplementerId = rawModel.ImplementerId;
            }
            model.Status = orderStatus;
            model.DateCreate = vmodel.DateCreate;
            if (model.DateImplement == null)
                model.DateImplement = vmodel.DateImplement;
            if (vmodel.ImplementerId.HasValue)
                model.ImplementerId = vmodel.ImplementerId;
            model.IceCreamId = vmodel.IceCreamId;
            model.Sum = vmodel.Sum;
            model.Count = vmodel.Count;
			var result = _orderStorage.Update(model);
			if (result == null)
			{
				_logger.LogWarning("Update operation failed");
				return false;
			}
			SendOrderStatusMail(result.ClientId, $"Изменен статус заказа #{result.Id}", $"Заказ #{model.Id} изменен статус на {result.Status}");
			return true;
		}
    

            CheckModel(model);
            if (model.Status + 1 != newStatus && model.Status != OrderStatus.Ожидается)
            {
                _logger.LogWarning("Status update to " + newStatus.ToString() + " operation failed. Order status incorrect.");
                return false;
            }

            if (newStatus == OrderStatus.Готов)
            {
                var icecream = _iceCreamStorage.GetElement(new IceCreamSearchModel() { Id = model.IceCreamId });
                if (icecream == null)
                {
                    _logger.LogWarning("Status update to " + newStatus.ToString() + " operation failed. Icecream not found.");
                    return false;
                }
                if (CheckSupply(icecream, model.Count) == false)
                {
                    _logger.LogWarning("Status update to " + newStatus.ToString() + " operation failed. Shop supply error.");
                    model.Status = OrderStatus.Ожидается;
                    _orderStorage.Update(model);
                    return false;
                }
            }

            model.Status = newStatus;
            if (model.Status == OrderStatus.Выдан) model.DateImplement = DateTime.Now;
            if (_orderStorage.Update(model) == null)
            {
                model.Status--;
                _logger.LogWarning("Update operation failed");
                return false;
            }
            return true;
        }

        public bool CheckSupply(IIceCreamModel model, int count)
        {
            if (count <= 0)
            {
                _logger.LogWarning("Check then supply operation error. icecream count < 0.");
                return false;
            }

            int freeSpace = 0;
            foreach (var shop in _shopStorage.GetFullList())
            {
                freeSpace += shop.IceCreamMaxCount;
                foreach (var icecream in shop.ShopIceCreams)
                {
                    freeSpace -= icecream.Value.Item2;
                }
            }

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

            foreach (var shop in _shopStorage.GetFullList())
            {
                freeSpace = shop.IceCreamMaxCount;
                foreach (var icecream in shop.ShopIceCreams)
                {
                    freeSpace -= icecream.Value.Item2;
                }
                if (freeSpace == 0)
                {
                    continue;
                }
                if (freeSpace - count >= 0)
                {
                    if (_shopLogic.SupplyIceCreams(new() { Id = shop.Id }, model, count)) count = 0;
                    else
                    {
                        _logger.LogWarning("Supply error");
                        return false;
                    }
                }
                if (freeSpace - count < 0)
                {
                    if (_shopLogic.SupplyIceCreams(new() { Id = shop.Id }, model, freeSpace)) count -= freeSpace;
                    else
                    {
                        _logger.LogWarning("Supply error");
                        return false;
                    }
                }
                if (count <= 0)
                {
                    return true;
                }
            }
            return false;
        }

        public OrderViewModel? ReadElement(OrderSearchModel model)
        {
            if (model == null)
            {
                throw new ArgumentNullException(nameof(model));
            }
            _logger.LogInformation("ReadElement. Id:{ Id}", model.Id);
            var element = _orderStorage.GetElement(model);
            if (element == null)
            {
                _logger.LogWarning("ReadElement element not found");
                return null;
            }
            _logger.LogInformation("ReadElement find. Id:{Id}", element.Id);
            return element;
        }

		private bool SendOrderStatusMail(int clientId, string subject, string text)
		{
			var client = _clientLogic.ReadElement(new() { Id = clientId });
			if (client == null)
			{
				return false;
			}
			_mailWorker.MailSendAsync(new()
			{
				MailAddress = client.Email,
				Subject = subject,
				Text = text
			});
			return true;
		}
	}
}