using Microsoft.Extensions.Logging;
using UniversityContracts.BindingModels;
using UniversityContracts.BusinessLogicsContracts;
using UniversityContracts.SearchModels;
using UniversityContracts.StoragesContracts;
using UniversityContracts.ViewModels;

namespace UniversityBusinessLogic.BusinessLogics
{
    public class DirectionLogic : IDirectionLogic
    {
        private readonly ILogger _logger;
        private readonly IDirectionStorage _directionStorage;
        public DirectionLogic(ILogger<DirectionLogic> logger, IDirectionStorage directionStorage)
        {
            _logger = logger;
            _directionStorage = directionStorage;
        }

        public void CreateOrUpdate(DirectionBindingModel model)
        {
            var element = _directionStorage.GetElement(
               new DirectionBindingModel
               {
                   Name = model.Name
               });
            if (element != null && element.Id != model.Id)
            {
                throw new Exception("Такое направление уже существует");
            }
            if (model.Id != null)
            {
                _directionStorage.Update(model);
            }
            else
            {
                _directionStorage.Insert(model);
            }
        }        

        public bool Delete(DirectionBindingModel model)
        {
            CheckModel(model, false);
            _logger.LogInformation("Delete. Id:{Id}", model.Id);
            if (_directionStorage.Delete(model) == null)
            {
                _logger.LogWarning("Delete operation failed");
                return false;
            }
            return true;
        }

        public DirectionViewModel? ReadElement(DirectionBindingModel model)
        {
            if (model == null)
            {
                throw new ArgumentNullException(nameof(model));
            }
            _logger.LogInformation("ReadElement. Name:{Name}. Id:{ Id}", model.Name, model.Id);
            var element = _directionStorage.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<DirectionViewModel>? ReadList(DirectionBindingModel? model)
        {
            _logger.LogInformation("ReadList. Name:{Name}. Id:{ Id}", model?.Name, model?.Id);
            var list = model == null ? _directionStorage.GetFullList() : _directionStorage.GetFilteredList(model);
            if (list == null)
            {
                _logger.LogWarning("ReadList return null list");
                return null;
            }
            _logger.LogInformation("ReadList. Count:{Count}", list.Count);
            return list;
        }        

        private void CheckModel(DirectionBindingModel model, bool withParams = true)
        {
            if (model == null)
            {
                throw new ArgumentNullException(nameof(model));
            }
            if (!withParams)
            {
                return;
            }
            if (string.IsNullOrEmpty(model.Name))
            {
                throw new ArgumentNullException("Нет названия направления", nameof(model.Name));
            }
            _logger.LogInformation("Direction. Name:{Name}. Id: {Id} ", model.Name, model.Id);
            var element = _directionStorage.GetElement(new DirectionBindingModel
            {
                Name = model.Name
            });
            if (element != null && element.Id != model.Id)
            {
                throw new InvalidOperationException("Направление с таким названием уже есть");
            }
        }
    }
}