public static void InsertFeedItem(RssFeedItemRow item)
        {
            using (var db = new LiteDatabase(GetDbPath()))
            {
                var col = db.GetCollection <RssFeedItemRow>("feedItems");

                //item.RssChannelDomainGroup = string.IsNullOrEmpty(item.RssChannelDomainGroup) ? item.Link : item.RssChannelDomainGroup;
                item.PublishingDate = item.PublishingDate == null || item.PublishingDate == DateTime.MinValue ? DateTime.Now : item.PublishingDate;

                col.Insert(item);
            }
        }
        public static void CrawlRss()
        {
            var logFolder = $"{Path.Combine(EnvironmentHelper.GetApplicationRoot(), "../Logs/")}";

            if (!Directory.Exists(logFolder))
            {
                Directory.CreateDirectory(logFolder);
            }

            var existedLogFiles = Directory.GetFiles(logFolder);

            var logFileBank = new Dictionary <DateTime, string>();

            foreach (var file in existedLogFiles)
            {
                var dtFormatArr = Path.GetFileNameWithoutExtension(file).Split('-');
                if (dtFormatArr.Length > 0)
                {
                    var dtText = dtFormatArr[0];
                    if (DateTime.TryParseExact(dtText, LogDateTimeFormat, CultureInfo.InvariantCulture, DateTimeStyles.None, out DateTime dt))
                    {
                        logFileBank.Add(dt, file);
                    }
                }
            }

            foreach (var kv in logFileBank)
            {
                if (kv.Key < DateTime.Now.AddDays(-10)) // just keep 10 days nearest
                {
                    File.Delete(kv.Value);
                }
            }

            var logPath = $"{Path.Combine(logFolder, $"{DateTime.Now.ToString(LogDateTimeFormat)}-crawler.txt")}";

            var _logger = new MyLogger(logPath);

            var feedUrl = string.Empty;

            try
            {
                List <RssChannelRow> channels = channels = SimpleFeedlyDatabaseAccess.GetActiveChannels().OrderBy(x => x.Id).ToList();

                _logger.Info($"There are {channels.Count} active channels");

                //channels = channels.Take(5).ToList();

                var progressCounter = 0;
                foreach (var channel in channels)
                {
                    progressCounter++;

                    feedUrl = channel.Link;

                    if (string.IsNullOrWhiteSpace(feedUrl))
                    {
                        continue;
                    }

                    try
                    {
                        _logger.Info($"- [{progressCounter}/{channels.Count}] Fetching url {feedUrl}");
                        var feed = GetFeedsFromChannel(feedUrl, channel.RssCrawlerEngine, out RssCrawlerEngine usedEngine, out Exception fetchFeedError);

                        _logger.Info($"  - Nbr of feed items {feed?.Items?.Count ?? 0}");

                        // update default engine for channel
                        SimpleFeedlyDatabaseAccess.UpdateChannelDefaultEngine(channel.Id, fetchFeedError != null ? RssCrawlerEngine.CodeHollowFeedReader : usedEngine);

                        if (feed != null && feed?.Items != null)
                        {
                            var top10LatestItems = feed.Items;
                            //.OrderByDescending(x => x.PublishingDate)
                            //.Take(10)
                            //.ToList();

                            if (top10LatestItems.Count == 0)
                            {
                                continue;
                            }
                            else
                            {
                                SimpleFeedlyDatabaseAccess.DeleteAllFeedItemByChannelId(channel.Id);
                                _logger.Info($"  - Deleted old items");

                                var insertItems = new List <RssFeedItemRow>();

                                foreach (var fItem in top10LatestItems)
                                {
                                    if (!StringUtils.IsUrl(fItem.Link))
                                    {
                                        continue;
                                    }

                                    var feedItemKey = GenerateFeedItemKey(fItem);

                                    if (string.IsNullOrWhiteSpace(feedItemKey) || string.IsNullOrWhiteSpace(fItem.Link))
                                    {
                                        continue;
                                    }

                                    var feedItem = new RssFeedItemRow
                                    {
                                        Channel        = channel,
                                        FeedItemKey    = feedItemKey,
                                        Title          = string.IsNullOrWhiteSpace(fItem.Title) ? fItem.Link : fItem.Title,
                                        Link           = fItem.Link,
                                        Description    = fItem.Description,
                                        PublishingDate = fItem.PublishingDate,
                                        Author         = fItem.Author
                                    };

                                    var shrinkedTitle     = StringUtils.UnsignString(StringUtils.RemoveNonAlphaCharactersAndDigit(feedItem.Title)).ToLower();
                                    var shrinkedTitleHash = StringUtils.MD5Hash(shrinkedTitle);

                                    if (!SimpleFeedlyDatabaseAccess.IsBlackListWord(shrinkedTitleHash))
                                    {
                                        var channelDomainGroup = string.IsNullOrEmpty(channel.DomainGroup) ? channel.Link : channel.DomainGroup;

                                        if (!SimpleFeedlyDatabaseAccess.IsExistedFeedItem(channel.Id, channelDomainGroup, feedItem.FeedItemKey))
                                        {
                                            //var coverImageUrl = fItem.GetFeedCoverImage();
                                            //if (!string.IsNullOrWhiteSpace(coverImageUrl))
                                            //{
                                            //    feedItem.CoverImageUrl = coverImageUrl;
                                            //}

                                            insertItems.Add(feedItem);
                                        }
                                    }
                                }

                                SimpleFeedlyDatabaseAccess.InsertFeedItems(insertItems);

                                _logger.Info($"  - Inserted {insertItems.Count()} items");
                            }

                            SimpleFeedlyDatabaseAccess.UpdateChannelErrorStatus(channel.Id, false, null);
                            _logger.Info($"  - Updated status");
                        }
                        else
                        {
                            _logger.Info($"  - [NO ITEMS]");
                            SimpleFeedlyDatabaseAccess.UpdateChannelErrorStatus(channel.Id, true, fetchFeedError == null ? null : JsonConvert.SerializeObject(fetchFeedError));

                            if (fetchFeedError != null)
                            {
                                ErrorHandle(fetchFeedError, feedUrl);
                            }
                        }
                    }
                    catch (Exception err)
                    {
                        _logger.Error($"  - Got Error: {JsonConvert.SerializeObject(err, new JsonSerializerSettings { ReferenceLoopHandling = ReferenceLoopHandling.Ignore })}");

                        SimpleFeedlyDatabaseAccess.UpdateChannelErrorStatus(channel.Id, true, JsonConvert.SerializeObject(err));
                        ErrorHandle(err, feedUrl);
                    }
                }
            }
            catch (Exception ex)
            {
                _logger.Error($"  - [ERROR]: {JsonConvert.SerializeObject(ex, new JsonSerializerSettings { ReferenceLoopHandling = ReferenceLoopHandling.Ignore })}");

                ErrorHandle(ex, feedUrl);
            }

            _logger.Info($"Done!");
        }