using Microsoft.Extensions.Logging;
using StudentEnrollmentContracts.BindingModels;
using StudentEnrollmentContracts.BusinessLogicContracts;
using StudentEnrollmentContracts.SearchModels;
using StudentEnrollmentContracts.StorageContracts;
using StudentEnrollmentContracts.ViewModels;

namespace StudentEnrollmentBusinessLogic
{
	public class CourseLogic : ICourseLogic
	{
		private readonly ILogger _logger;
		private readonly ICourseStorage _courseStorage;
		public CourseLogic(ILogger<CourseLogic> logger, ICourseStorage
	   courseStorage)
		{
			_logger = logger;
			_courseStorage = courseStorage;
		}
		public List<CourseViewModel>? ReadList(CourseSearchModel? model)
		{
			_logger.LogInformation("ReadList. CourseName:{CourseName}.Id:{ Id}", model?.CourseName, model?.Id);
			var list = model == null ? _courseStorage.GetFullList() :
			_courseStorage.GetFilteredList(model);
			if (list == null)
			{
				_logger.LogWarning("ReadList return null list");
				return null;
			}
			_logger.LogInformation("ReadList. Count:{Count}", list.Count);
			return list;
		}
		public CourseViewModel? ReadElement(CourseSearchModel model)
		{
			if (model == null)
			{
				throw new ArgumentNullException(nameof(model));
			}
			_logger.LogInformation("ReadElement. CourseName:{CourseName}.Id:{ Id}", model.CourseName, model.Id);
			var element = _courseStorage.GetElement(model);
			if (element == null)
			{
				_logger.LogWarning("ReadElement element not found");
				return null;
			}
			_logger.LogInformation("ReadElement find. Id:{Id}", element.Id);
			return element;
		}
		public bool Create(CourseBindingModel model)
		{
			CheckModel(model);
			if (_courseStorage.Insert(model) == null)
			{
				_logger.LogWarning("Insert operation failed");
				return false;
			}
			return true;
		}
		public bool Update(CourseBindingModel model)
		{
			CheckModel(model);
			if (_courseStorage.Update(model) == null)
			{
				_logger.LogWarning("Update operation failed");
				return false;
			}
			return true;
		}
		public bool Delete(CourseBindingModel model)
		{
			CheckModel(model, false);
			_logger.LogInformation("Delete. Id:{Id}", model.Id);
			if (_courseStorage.Delete(model) == null)
			{
				_logger.LogWarning("Delete operation failed");
				return false;
			}
			return true;
		}
		private void CheckModel(CourseBindingModel model, bool withParams = true)
		{
			if (model == null)
			{
				throw new ArgumentNullException(nameof(model));
			}
			if (!withParams)
			{
				return;
			}
			if (string.IsNullOrEmpty(model.CourseName))
			{
				throw new ArgumentNullException("Нет названия направления!",
			   nameof(model.CourseName));
			}
			_logger.LogInformation("Course. CourseName:{CourseName}. Id: { Id}", model.CourseName, model.Id);
			var element = _courseStorage.GetElement(new CourseSearchModel
			{
				CourseName = model.CourseName
			});
			if (element != null && element.Id != model.Id)
			{
				throw new InvalidOperationException("Направление с таким названием уже есть");
			}
		}
	}
}