using Core.Enumerations;
using DataProviders;
using DomainResults.Common;
using WeatherForecast.Models.Requests;
using WeatherForecast.Models.Responses;

namespace WeatherForecast.Services {

  /// <summary>
  /// 
  /// </summary>
  public interface ICategoryItemService {

    /// <summary>
    /// 
    /// </summary>
    /// <param name="siteId"></param>
    /// <param name="requestModel"></param>
    /// <returns></returns>
    (Guid?, IDomainResult) Post(Guid siteId, CategoryItemRequestModel requestModel);

    /// <summary>
    /// 
    /// </summary>
    /// <param name="siteId"></param>
    /// <param name="categoryId"></param>
    /// <returns></returns>
    (CategoryItemResponseModel?, IDomainResult) Get(Guid siteId, Guid categoryId);

    /// <summary>
    /// 
    /// </summary>
    /// <param name="siteId"></param>
    /// <param name="slug"></param>
    /// <returns></returns>
    (CategoryItemResponseModel?, IDomainResult) GetSlug(Guid siteId, string slug);

    /// <summary>
    /// 
    /// </summary>
    /// <param name="siteId"></param>
    /// <param name="categoryId"></param>
    /// <param name="requestData"></param>
    /// <returns></returns>
    (Guid?, IDomainResult) Update(Guid siteId, Guid categoryId, CategoryItemRequestModel requestData);

    /// <summary>
    /// 
    /// </summary>
    /// <param name="siteId"></param>
    /// <param name="categoryId"></param>
    /// <returns></returns>
    IDomainResult Delete(Guid siteId, Guid categoryId);
  }

  /// <summary>
  /// 
  /// </summary>
  public class CategoryItemService : ICategoryItemService {

    private readonly ILogger<CategoryItemService> _logger;
    private readonly ICategoryDataProvider _categoryDataProvider;

    /// <summary>
    /// 
    /// </summary>
    /// <param name="logger"></param>
    /// <param name="categoryDataProvider"></param>
    public CategoryItemService(
      ILogger<CategoryItemService> logger,
      ICategoryDataProvider categoryDataProvider
    ) {
      _logger = logger;
      _categoryDataProvider = categoryDataProvider;
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="siteId"></param>
    /// <param name="requestModel"></param>
    /// <returns></returns>
    public (Guid?, IDomainResult) Post(Guid siteId, CategoryItemRequestModel requestModel) {
      var (_, getResult) = _categoryDataProvider.GetBySlugs(siteId, requestModel.L10n.Select(x => x.Slug).ToList());
      if (getResult.IsSuccess)
        return IDomainResult.Failed<Guid?>();

      var item = requestModel.ToDomainObject();
      item.SiteId = siteId;


      var (id, insertResult) = _categoryDataProvider.Insert(item);

      if (!insertResult.IsSuccess)
        return IDomainResult.Failed<Guid?>();

      return IDomainResult.Success(id);
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="siteId"></param>
    /// <param name="categoryId"></param>
    /// <returns></returns>
    public (CategoryItemResponseModel?, IDomainResult) Get(Guid siteId, Guid categoryId) {
      var (item, result) = _categoryDataProvider.Get(siteId, categoryId);
      if (!result.IsSuccess || item == null)
        return (null, result);

      return IDomainResult.Success(new CategoryItemResponseModel(item));
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="siteId"></param>
    /// <param name="slug"></param>
    /// <returns></returns>
    public (CategoryItemResponseModel?, IDomainResult) GetSlug(Guid siteId, string slug) {
      var (item, result) = _categoryDataProvider.GetBySlug(siteId, slug);
      if (!result.IsSuccess || item == null)
        return (null, result);

      var locale = item.L10n.SingleOrDefault(x => x.Slug == slug)?.Locale ?? Locales.Us; 

      return IDomainResult.Success(new CategoryItemResponseModel(item, locale));
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="siteId"></param>
    /// <param name="categoryId"></param>
    /// <param name="requestData"></param>
    /// <returns></returns>
    public (Guid?, IDomainResult) Update(Guid siteId, Guid categoryId, CategoryItemRequestModel requestData) {
      var (item, result) = _categoryDataProvider.Get(siteId, categoryId);
      if (!result.IsSuccess || item == null)
        return (null, result);

      // construct domain object from model
      var newItem = requestData.ToDomainObject();
      newItem.Id = item.Id;
      newItem.SiteId = item.SiteId;

      if (!item.Equals(newItem)) {
        var (id, updateResult) = _categoryDataProvider.Update(newItem);
        if (!updateResult.IsSuccess || id == null)
          return (null, updateResult);
      }

      return IDomainResult.Success(item.Id);
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="siteId"></param>
    /// <param name="categoryId"></param>
    /// <returns></returns>
    public IDomainResult Delete(Guid siteId, Guid categoryId) {
      var (item, getResult) = _categoryDataProvider.Get(siteId, categoryId);
      if (!getResult.IsSuccess || item == null)
        return getResult;

      var result = _categoryDataProvider.Delete(item.Id);
      if (!result.IsSuccess)
        return result;

      return IDomainResult.Success();
    }
  }
}