using Microsoft.Extensions.Logging;
using RouteGuideContracts.BindingModels;
using RouteGuideContracts.BusinessLogicsContracts;
using RouteGuideContracts.SearchModels;
using RouteGuideContracts.StoragesContracts;
using RouteGuideContracts.ViewModels;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace RouteGuideBusinessLogics.BusinessLogics
{
    /// <summary>
    /// Бизнес-логика для сущности "Транспорт"
    /// </summary>
    public class TransportLogic : ITransportLogic
    {
        /// <summary>
        /// Логгер
        /// </summary>
        private readonly ILogger _logger;

        /// <summary>
        /// Хранилище
        /// </summary>
        private readonly ITransportStorage _transportStorage;

        /// <summary>
        /// Конструктор
        /// </summary>
        /// <param name="logger"></param>
        /// <param name="transportStorage"></param>
        public TransportLogic(ILogger<TransportLogic> logger, ITransportStorage transportStorage)
        {
            _logger = logger;
            _transportStorage = transportStorage;
        }

        /// <summary>
        /// Получение списка
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        public List<TransportViewModel>? ReadList(TransportSearchModel? model)
        {
            _logger.LogInformation("ReadList. Transport: {Id}.{License}", model?.Id, model?.License);

            var list = model == null ? _transportStorage.GetFullList() : _transportStorage.GetFilteredList(model);
            if (list == null)
            {
                _logger.LogWarning("ReadList. Returned null list");
                return null;
            }

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

        /// <summary>
        /// Получение списка из заданного количества элементов
        /// </summary>
        /// <param name="count"></param>
        /// <returns></returns>
        public List<TransportViewModel>? ReadList(int count)
        {
            _logger.LogInformation("ReadList. Count: {Count}", count);

            var list = _transportStorage.GetList(count);
            if (list == null)
            {
                _logger.LogWarning("ReadList. Returned null list");
                return null;
            }

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

        /// <summary>
        /// Получение отдельной записи
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        /// <exception cref="ArgumentNullException"></exception>
        public TransportViewModel? ReadElement(TransportSearchModel model)
        {
            if (model == null)
            {
                throw new ArgumentNullException(nameof(model));
            }

            _logger.LogInformation("ReadElement. Transport: {Id}.{License}", model?.Id, model?.License);

            var element = _transportStorage.GetElement(model!);
            if (element == null)
            {
                _logger.LogWarning("ReadElement. Element not found");
                return null;
            }

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

        /// <summary>
        /// Создание записи
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        public bool Create(TransportBindingModel model)
        {
            CheckModel(model);
            _logger.LogInformation("Create. Transport.Id: {Id}", model.Id);

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

        /// <summary>
        /// Изменение записи
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        public bool Update(TransportBindingModel model)
        {
            CheckModel(model);
            _logger.LogInformation("Update. Transport.Id: {Id}", model.Id);

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

        /// <summary>
        /// Удаление записи
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        public bool Delete(TransportBindingModel model)
        {
            CheckModel(model, false);
            _logger.LogInformation("Delete. Transport.Id: {Id}", model.Id);

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

        /// <summary>
        /// Удаление записи
        /// </summary>
        /// <returns></returns>
        public bool Delete()
        {
            _logger.LogInformation("Delete. Transport");

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

        /// <summary>
        /// Удаление всех записей
        /// </summary>
        /// <returns></returns>
        public int Clear()
        {
            int count = _transportStorage.Clear();
            _logger.LogInformation("Clear. Delete {Count} Transports", count);
            return count;
        }

        /// <summary>
        /// Проверка модели
        /// </summary>
        /// <param name="model"></param>
        /// <param name="withParams"></param>
        private void CheckModel(TransportBindingModel model, bool withParams = true)
        {
            if (model == null)
            {
                throw new ArgumentNullException(nameof(model));
            }
            if (!withParams)
            {
                return;
            }
            if (string.IsNullOrEmpty(model.License))
            {
                throw new ArgumentNullException("Не указан номерной знак транспортного средства", nameof(model.License));
            }
            if (model.Capacity <= 0)
            {
                throw new ArgumentNullException("Вместимость транспортного средства должна быть положительным числом", nameof(model.Capacity));
            }
            if (model.DriverId < 0)
            {
                throw new ArgumentNullException("Некорректный идентификатор водителя", nameof(model.DriverId));
            }

            _logger.LogInformation("CheckModel. Transport.Id: {Id}", model.Id);

            var element = _transportStorage.GetElement(new TransportSearchModel
            {
                License = model.License
            });
            if (element != null && element.Id != model.Id)
            {
                throw new InvalidOperationException("Транспортное средство с таким номерным знаком уже есть");
            }
        }
    }
}