using ComputersShopContracts.BindingModels;
using ComputersShopContracts.BusinessLogicContracts;
using ComputersShopContracts.SearchModels;
using ComputersShopContracts.StoragesContracts;
using ComputersShopContracts.ViewModels;
using ComputersShopDataModels.Models;
using Microsoft.Extensions.Logging;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Threading.Tasks;

namespace ComputersShopBusinessLogic.BusinessLogics
{
    public class ShopLogic : IShopLogic
    {
        private readonly ILogger _logger;
        private readonly IShopStorage _shopStorage;
        public ShopLogic(ILogger<ShopLogic> logger, IShopStorage ShopStorage)
        {
            _logger = logger;
            _shopStorage = ShopStorage;
        }
        public bool AddComputer(ShopSearchModel model, IComputerModel computer, int quantity)
        {
            if (model == null)
            {
                throw new ArgumentNullException(nameof(model));
            }

            if (quantity <= 0)
            {
                return false;
                throw new ArgumentException("Количество добавляемого компьютера должно быть больше 0", nameof(quantity));
            }

            _logger.LogInformation("AddComputerInShop. ShopName:{ShopName}.Id:{ Id}", model.ShopName, model.Id);
            var element = _shopStorage.GetElement(model);

            if (element == null)
            {
                _logger.LogWarning("AddComputerInShop element not found");
                return false;
            }

            if (element.Capacity - element.Computers.Select(x => x.Value.Item2).Sum() < quantity)
            {
                throw new ArgumentNullException("В магазине не хватает места", nameof(quantity));
            }

            if (element.Computers.TryGetValue(computer.Id, out var pair))
            {
                element.Computers[computer.Id] = (computer, quantity + pair.Item2);
                _logger.LogInformation("AddComputerInShop. Has been added {quantity} {Computer} in {ShopName}", quantity, computer.ComputerName, element.ShopName);
            }
            else
            {
                element.Computers[computer.Id] = (computer, quantity);
                _logger.LogInformation("AddPastryInShop. Has been added {quantity} new Computer {Computer} in {ShopName}", quantity, computer.ComputerName, element.ShopName);
            }

            _shopStorage.Update(new()
            {
                Id = element.Id,
                ShopAddress = element.ShopAddress,
                ShopName = element.ShopName,
                DateOpening = element.DateOpening,
                Computers = element.Computers,
                Capacity = element.Capacity,
            });
            return true;
        }

        public bool AddComputers(IComputerModel computer, int quantity)
        {
            if (computer == null)
            {
                throw new ArgumentNullException(nameof(computer));
            }
            if (quantity <= 0)
            {
                throw new ArgumentException("Количество компьютеров должно быть больше 0", nameof(quantity));
            }
            _logger.LogInformation("AddComputers. ShopName:{ShopName}. Id:{Id}", computer.ComputerName, computer.Id);
            var allFreeQuantity = _shopStorage.GetFullList().Select(x => x.Capacity - x.Computers.Select(x => x.Value.Item2).Sum()).Sum();
            if (allFreeQuantity < quantity)
            {
                _logger.LogWarning("AddComputers operation failed.");
                return false;
            }
            foreach (var shop in _shopStorage.GetFullList())
            {
                int freeQuantity = shop.Capacity - shop.Computers.Select(x => x.Value.Item2).Sum();
                if (freeQuantity <= 0)
                {
                    continue;
                }
                if (freeQuantity < quantity)
                {
                    if (!AddComputer(new() { Id = shop.Id }, computer, freeQuantity))
                    {
                        _logger.LogWarning("AddComputers operation failed.");
                        return false;
                    }
                    quantity -= freeQuantity;
                }
                else
                {
                    if (!AddComputer(new() { Id = shop.Id }, computer, quantity))
                    {
                        _logger.LogWarning("AddComputers operation failed.");
                        return false;
                    }
                    quantity = 0;
                }
                if (quantity == 0)
                {
                    return true;
                }
            }
            _logger.LogWarning("AddComputers operation failed.");
            return false;
        }

        public bool Create(ShopBindingModel model)
        {
            CheckModel(model);
            model.Computers = new();

            if (_shopStorage.Insert(model) == null)
            {
                _logger.LogWarning("Insert operation failed");
                return false;
            }

            return true;
        }

        public bool Delete(ShopBindingModel model)
        {
            CheckModel(model, false);
            _logger.LogInformation("Delete. Id:{Id}", model.Id);

            if (_shopStorage.Delete(model) == null)
            {
                _logger.LogWarning("Delete operation failed");
                return false;
            }

            return true;
        }

        public ShopViewModel? ReadElement(ShopSearchModel model)
        {
            if (model == null)
            {
                throw new ArgumentNullException(nameof(model));
            }

            _logger.LogInformation("ReadElement. ShopName:{ShopName}.Id:{ Id}", model.ShopName, model.Id);
            var element = _shopStorage.GetElement(model);

            if (element == null)
            {
                _logger.LogWarning("ReadElement element not found");
                return null;
            }

            _logger.LogInformation("ReadElement find. Id:{Id}", element.Id);
            return element;
        }

        public List<ShopViewModel>? ReadList(ShopSearchModel? model)
        {
            _logger.LogInformation("ReadList. ShopName:{ShopName}.Id:{ Id} ", model?.ShopName, model?.Id);

            var list = (model == null) ? _shopStorage.GetFullList() : _shopStorage.GetFilteredList(model);

            if (list == null)
            {
                _logger.LogWarning("ReadList return null list");
                return null;
            }

            _logger.LogInformation("ReadList. Count:{Count}", list.Count);
            return list;
        }

        public bool SellComputers(IComputerModel computer, int quantity)
        {
            return _shopStorage.SellComputers(computer, quantity);
        }

        public bool Update(ShopBindingModel model)
        {
            CheckModel(model, false);

            if (string.IsNullOrEmpty(model.ShopName))
            {
                throw new ArgumentNullException("Нет названия магазина", nameof(model.ShopName));
            }

            if (_shopStorage.Update(model) == null)
            {
                _logger.LogWarning("Update operation failed");
                return false;
            }
            return true;
        }

        private void CheckModel(ShopBindingModel model, bool withParams = true)
        {
            if (model == null)
            {
                throw new ArgumentNullException(nameof(model));
            }

            if (!withParams)
            {
                return;
            }

            if (string.IsNullOrEmpty(model.ShopName))
            {
                throw new ArgumentNullException("Нет названия магазина", nameof(model.ShopName));
            }

            _logger.LogInformation("Shop. ShopName:{0}.ShopAdress:{1}. Id: {2}", model.ShopName, model.ShopAddress, model.Id);
            var element = _shopStorage.GetElement(new ShopSearchModel
            {
                ShopName = model.ShopName
            });

            if (element != null && element.Id != model.Id && element.ShopName == model.ShopName)
            {
                throw new InvalidOperationException("Магазин с таким названием уже есть");
            }
        }
    }
}