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 "Пациент"
	/// </summary>
	public class PatientLogic : IPatientLogic
	{
		/// <summary>
		/// Логгер
		/// </summary>
		private readonly ILogger _logger;

		/// <summary>
		/// Хранилище
		/// </summary>
		private readonly IPatientStorage _patientStorage;

		/// <summary>
		/// Конструктор
		/// </summary>
		/// <param name="logger"></param>
		/// <param name="patientStorage"></param>
		public PatientLogic(ILogger<PatientLogic> logger, IPatientStorage patientStorage)
		{
			_logger = logger;
			_patientStorage = patientStorage;
		}

		/// <summary>
		/// Получить список
		/// </summary>
		/// <param name="model"></param>
		/// <returns></returns>
		public List<PatientViewModel>? ReadList(PatientSearchModel? model)
		{
			_logger.LogInformation("ReadList. Patient.Id: {Id}. DoctorId: {DoctorId}. FullName: {FullName}", model?.Id, model?.DoctorId, model?.FullName);

			var list = model == null ? _patientStorage.GetFullList() : _patientStorage.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 PatientViewModel? ReadElement(PatientSearchModel model)
		{
			if (model == null)
			{
				throw new ArgumentNullException(nameof(model));
			}

			_logger.LogInformation("ReadElement. Patient.Id: {Id}. Phone: {Phone}", model?.Id, model?.Phone);

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

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

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

			if (_patientStorage.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(PatientBindingModel model)
		{
			CheckModel(model);
			_logger.LogInformation("Update. Patient.Id: {Id}", model.Id);

			if (_patientStorage.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(PatientBindingModel model)
		{
			CheckModel(model, false);
			_logger.LogInformation("Delete. Patient.Id: {Id}", model.Id);

			if (_patientStorage.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(PatientBindingModel model, bool withParams = true)
		{
			if (model == null)
			{
				throw new ArgumentNullException(nameof(model));
			}
			if (!withParams)
			{
				return;
			}
			if (string.IsNullOrEmpty(model.FullName))
			{
				throw new ArgumentNullException("Не указано ФИО пациента", nameof(model.FullName));
			}
			if (model.BirthDate == DateTime.MinValue)
			{
				throw new ArgumentNullException("Не указана дата рождения пациента", nameof(model.BirthDate));
			}
			if (string.IsNullOrEmpty(model.Phone))
			{
				throw new ArgumentNullException("Не указан номер телефона", nameof(model.Phone));
			}
			if (model.DoctorId <= 0)
			{
				throw new ArgumentNullException("Не указан идентификатор лечащего врача", nameof(model.DoctorId));
			}

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

			var element = _patientStorage.GetElement(new PatientSearchModel
			{
				Phone = model.Phone
			});
			if (element != null && !element.Id.Equals(model.Id))
			{
				throw new InvalidOperationException("Пациент с таким номером телефона уже существует");
			}
		}
	}
}