using ForumContracts.BindingModels;
using ForumContracts.BusinessLogicContracts;
using ForumContracts.SearchModels;
using ForumContracts.StoragesContracts;
using ForumContracts.ViewModels;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ForumBusinessLogic
{
    public class TopicLogic : ITopicLogic
    {
        private readonly ITopicStorage _topicStorage;

        public TopicLogic(ITopicStorage topicStorage)
        {
            _topicStorage = topicStorage;
        }

        public bool Create(TopicBindingModel model)
        {
            CheckModel(model);
            if (_topicStorage.Insert(model) == null)
            {
                return false;
            }
            return true;
        }

        public bool Delete(TopicBindingModel model)
        {
            CheckModel(model, false);
            if (_topicStorage.Delete(model) == null)
            {
                return false;
            }
            return true;
        }

        public TopicViewModel? ReadElement(TopicSearchModel model)
        {
            if (model == null)
            {
                throw new ArgumentNullException(nameof(model));
            }
            var element = _topicStorage.GetElement(model);
            if (element == null)
            {
                return null;
            }
            return element;
        }

        public List<TopicViewModel>? ReadList(TopicSearchModel? model)
        {
            var list = model == null ? _topicStorage.GetFullList() : _topicStorage.GetFilteredList(model);
            if (list == null)
            {
                return null;
            }
            return list;
        }

        public bool Update(TopicBindingModel model)
        {
            CheckModel(model);
            if (_topicStorage.Update(model) == null)
            {
                return false;
            }
            return true;
        }

        private void CheckModel(TopicBindingModel 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 темы", nameof(model.Name));
            }

            var element = _topicStorage.GetElement(new TopicSearchModel
            {
                Name = model.Name
            }
            );
        }
    }
}