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

namespace HospitalBusinessLogics.BusinessLogics
{
	/// <summary>
	/// Бизнес-логика для сущности "Лекарство"
	/// </summary>
	public class MedicineLogic : IMedicineLogic
	{
		/// <summary>
		/// Логгер
		/// </summary>
		private readonly ILogger _logger;

		/// <summary>
		/// Хранилище
		/// </summary>
		private readonly IMedicineStorage _medicineStorage;

		/// <summary>
		/// Конструктор
		/// </summary>
		/// <param name="logger"></param>
		/// <param name="medicineStorage"></param>
		public MedicineLogic(ILogger<MedicineLogic> logger, IMedicineStorage medicineStorage)
		{
			_logger = logger;
			_medicineStorage = medicineStorage;
		}

		/// <summary>
		/// Получить список
		/// </summary>
		/// <param name="model"></param>
		/// <returns></returns>
		public List<MedicineViewModel>? ReadList(MedicineSearchModel? model)
		{
			_logger.LogInformation("ReadList. Medicine.Id: {Id}. Name: {Name}", model?.Id, model?.Name);

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

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

		/// <summary>
		/// Получить отдельную запись
		/// </summary>
		/// <param name="model"></param>
		/// <returns></returns>
		/// <exception cref="ArgumentNullException"></exception>
		public MedicineViewModel? ReadElement(MedicineSearchModel model)
		{
			if (model == null)
			{
				throw new ArgumentNullException(nameof(model));
			}

			_logger.LogInformation("ReadElement. Medicine.Id: {Id}. Name: {Name}", model?.Id, model?.Name);

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

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

		/// <summary>
		/// Создать запись
		/// </summary>
		/// <param name="model"></param>
		/// <returns></returns>
		public bool Create(MedicineBindingModel model)
		{
			CheckModel(model);
			_logger.LogInformation("Create. Medicine.Id: {Id}", model.Id);

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

		/// <summary>
		/// Изменить запись
		/// </summary>
		/// <param name="model"></param>
		/// <returns></returns>
		public bool Update(MedicineBindingModel model)
		{
			CheckModel(model);
			_logger.LogInformation("Update. Medicine.Id: {Id}", model.Id);

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

		/// <summary>
		/// Удалить запись
		/// </summary>
		/// <param name="model"></param>
		/// <returns></returns>
		public bool Delete(MedicineBindingModel model)
		{
			CheckModel(model, false);
			_logger.LogInformation("Delete. Medicine.Id: {Id}", model.Id);

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

		/// <summary>
		/// Проверка модели
		/// </summary>
		/// <param name="model"></param>
		/// <param name="withParams"></param>
		/// <exception cref="ArgumentNullException"></exception>
		/// <exception cref="InvalidOperationException"></exception>
		private void CheckModel(MedicineBindingModel model, bool withParams = true)
		{
			if (model == null)
			{
				throw new ArgumentNullException(nameof(model));
			}
			if (!withParams)
			{
				return;
			}
			if (string.IsNullOrEmpty(model.Name))
			{
				throw new ArgumentNullException("Не указано название лекарства", nameof(model.Name));
			}

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

			var element = _medicineStorage.GetElement(new MedicineSearchModel
			{
				Name = model.Name
			});
			if (element != null && !element.Id.Equals(model.Id))
			{
				throw new InvalidOperationException("Лекарство с таким названием уже существует");
			}
		}
	}
}