using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using CodeHollow.FeedReader;
using SharpRss.Models;

namespace SharpRss
{
    /// <summary>
    /// Managing RSS feeds and categories.
    /// </summary>
    public class RssService
    {
        public RssService()
        {
            /// Storage options:
            /// - Database
            /// - File
            /// - Memory
            combined.UnionWith(feedSet);
            combined.UnionWith(feedSet2);
        }

        private static HashSet<FeedModel> feedSet = new HashSet<FeedModel>()
        {
            new FeedModel("http://fedoramagazine.org/feed/"),
            new FeedModel("https://www.nasa.gov/rss/dyn/breaking_news.rss"),
        };
        private static HashSet<FeedModel> feedSet2 = new HashSet<FeedModel>()
        {
            new FeedModel("https://journals.plos.org/plosone/feed/atom"),
            new FeedModel("https://itsfoss.com/feed")
        };
        private static HashSet<FeedModel> combined = new HashSet<FeedModel>();
        
        HashSet<CategoryModel> set = new HashSet<CategoryModel>()
        {
            new CategoryModel("RSS", feedSet),
            new CategoryModel("Tech", feedSet2)
        };

        public async Task<HashSet<CategoryModel>> GetCategories()
        {
            return set;
        }

        public async Task<HashSet<FeedModel>> GetAllFeeds()
        {
            return combined;
        }


        /// Old

        public async Task<Feed> GetFeed(string feedUrl)
        {
            var urls = await FeedReader.GetFeedUrlsFromUrlAsync(feedUrl);
            string url;
            if (urls.Count() < 1)
                url = _feeds[0];
            else
                url = urls.First().Url;

            return await FeedReader.ReadAsync(url);
        }
        public async Task<HashSet<Feed>> GetFeedsFromCatAsync(CategoryModel category)
        {
            return new HashSet<Feed>();
        }

        private readonly string[] _feeds = { "https://www.reddit.com/r/freshrss/.rss", "http://fedoramagazine.org/" };
    }
}