using AbstractLawFirmContracts.BindingModels;
using AbstractLawFirmContracts.BusinessLogicsContracts;
using AbstractLawFirmContracts.SearchModels;
using AbstractLawFirmContracts.StoragesContracts;
using AbstractLawFirmContracts.ViewModels;
using AbstractLawFirmDataModels.Enums;
using AbstractLawFirmDataModels.Models;
using Microsoft.Extensions.Logging;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace AbstractLawFirmBusinessLogic.BusinessLogic
{
    public class OrderLogic : IOrderLogic
    {
        private readonly ILogger _logger;
        private readonly IOrderStorage _orderStorage;
        private readonly IShopStorage _shopStorage;
        private readonly IShopLogic _shopLogic;
        private readonly IDocumentStorage _documentStorage;

        public OrderLogic(ILogger<OrderLogic> logger, IOrderStorage orderStorage, IShopLogic shopLogic, IDocumentStorage documentStorage, IShopStorage shopStorage)
        {
            _logger = logger;
            _orderStorage = orderStorage;
            _shopLogic = shopLogic;
            _documentStorage = documentStorage;
            _shopStorage = shopStorage;
        }

        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)
            {
                model.Status = OrderStatus.Неизвестен;
                _logger.LogWarning("Insert operation failed");
                return false;
            }
            return true;
        }

        public bool ChangeStatus(OrderBindingModel model, OrderStatus status)
        {
            CheckModel(model, false);
            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 (status == OrderStatus.Готов)
            {
                var document = _documentStorage.GetElement(new DocumentSearchModel() { Id = model.DocumentId });
                if (document == null)
                {
                    _logger.LogWarning("Status change operation failed. Car not found.");
                    return false;
                }

                if (!CheckThenSupplyMany(document, model.Count))
                {
                    _logger.LogWarning("Status change operation failed. Shop supply error.");
                    return false;
                }
            }

            model.Status = status;
            if (model.Status == OrderStatus.Выдан) model.DateImplement = DateTime.Now;
            _orderStorage.Update(model);
            if (_orderStorage.Update(model) == null)
            {
                model.Status--;
                _logger.LogWarning("Update operation failed");
                return false;
            }
            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.DocumentId < 0)
            {
                throw new ArgumentNullException("Некорректный идентификатор документа", nameof(model.DocumentId));
            }
            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);
        }
        public bool CheckThenSupplyMany(IDocumentModel document, int count)
        {
            if (count <= 0)
            {
                _logger.LogWarning("Check then supply operation error. Car count < 0.");
                return false;
            }

            int freeSpace = 0;
            foreach (var shop in _shopStorage.GetFullList())
            {
                freeSpace += shop.MaxCountDocuments;
                foreach (var c in shop.ShopDocuments)
                {
                    freeSpace -= c.Value.Item2;
                }
            }

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

            foreach (var shop in _shopStorage.GetFullList())
            {
                freeSpace = shop.MaxCountDocuments;

                foreach (var c in shop.ShopDocuments)
                    freeSpace -= c.Value.Item2;

                if (freeSpace <= 0)
                    continue;

                if (freeSpace >= count)
                {
                    if (_shopLogic.SupplyDocuments(new ShopSearchModel() { Id = shop.Id }, document, count))
                        count = 0;
                    else
                    {
                        _logger.LogWarning("Supply error");
                        return false;
                    }
                }
                if (freeSpace < count)
                {
                    if (_shopLogic.SupplyDocuments(new ShopSearchModel() { Id = shop.Id }, document, freeSpace))
                        count -= freeSpace;
                    else
                    {
                        _logger.LogWarning("Supply error");
                        return false;
                    }
                }
                if (count <= 0)
                {
                    return true;
                }
            }
            return false;
        }

    }
}