using DataProviders;
using DomainResults.Common;
using WeatherForecast.Models;
using WeatherForecast.Models.Requests;

namespace WeatherForecast.Services {

  public interface IShopItemService {
    (GetShopItemResponseModel, IDomainResult) Get(Guid siteId, string sku);
  }

  public class ShopItemService : IShopItemService {

    private readonly ILogger<ShopItemService> _logger;
    private readonly IShopCatalogDataProvider _shopCatalogDataProvider;

    public ShopItemService(
      ILogger<ShopItemService> logger,
      IShopCatalogDataProvider shopCatalogDataProvider
    ) {
      _logger = logger;
      _shopCatalogDataProvider = shopCatalogDataProvider;
    }

    public (Guid?, IDomainResult) Post(Guid siteId, string sku, PostShopItemRequestModel requestModel) {
      var (_, getResult) = _shopCatalogDataProvider.Get(siteId, sku);
      if (getResult.IsSuccess)
        return IDomainResult.Failed<Guid?>();

      var item = requestModel.ToDomainObject();

      item.SiteId = siteId;
      item.Sku = sku;

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

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

      return IDomainResult.Success(id);
    }

    public (GetShopItemResponseModel?, IDomainResult) Get(Guid siteId, string sku) {
      var (item, result) = _shopCatalogDataProvider.Get(siteId, sku);

      if (!result.IsSuccess || item == null)
        return (null, result);

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

    public (Guid?, IDomainResult) Update(Guid siteId, string sku, PutShopItemRequestModel requestData) {
      var (item, getResult) = _shopCatalogDataProvider.Get(siteId, sku);
      if (!getResult.IsSuccess || item == null)
        return (null, getResult);

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

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

      return IDomainResult.Success(item.Id);
    }

    public IDomainResult Delete(Guid siteId, string sku) {
      var (item, getResult) = _shopCatalogDataProvider.Get(siteId, sku);
      if (!getResult.IsSuccess || item == null)
        return getResult;

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

      return IDomainResult.Success();
    }

  }
}