feat(News): refactor news service and add sentiment tracking

FinlyticNews/Services/ArticleDiscoveryService.cs

@@ -0,0 +1,97 @@
+using FinlyticCore.Dtos.News;
+using FinlyticNews.Adapters.Discovery;
+using Microsoft.Extensions.Logging;
+
+namespace FinlyticNews.Services;
+
+/// <summary>
+/// Defines operations for discovering article links from various news feeds and web pages.
+/// </summary>
+public interface IArticleDiscoveryService
+{
+    /// <summary>
+    /// Discovers article links from a given source URL using configured adapters.
+    /// </summary>
+    /// <param name="url">The URL of the source news page or feed.</param>
+    /// <param name="adapterType">The type identifier of the adapter to use (e.g. "rss", "html").</param>
+    /// <param name="ct">The token to monitor for cancellation requests.</param>
+    /// <returns>A list of discovered absolute article URLs (optionally carrying ISINs), or null if the URL was invalid.</returns>
+    Task<List<DiscoveredArticle>?> DiscoverLinksAsync(string url, string adapterType, CancellationToken ct = default);
+}
+
+/// <inheritdoc />
+public class ArticleDiscoveryService : IArticleDiscoveryService
+{
+    private readonly IEnumerable<ArticleDiscoveryAdapter> _adapters;
+    private readonly ILogger<ArticleDiscoveryService> _logger;
+    private readonly HttpClient _httpClient;
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="ArticleDiscoveryService"/> class.
+    /// </summary>
+    /// <param name="adapters">Registered list of specialized adapters.</param>
+    /// <param name="logger">The application logging channel.</param>
+    /// <param name="httpClient">The HTTP client to fetch feeds.</param>
+    public ArticleDiscoveryService(
+        IEnumerable<ArticleDiscoveryAdapter> adapters,
+        ILogger<ArticleDiscoveryService> logger,
+        HttpClient httpClient)
+    {
+        _adapters = adapters;
+        _logger = logger;
+        _httpClient = httpClient;
+    }
+
+    /// <inheritdoc />
+    public async Task<List<DiscoveredArticle>?> DiscoverLinksAsync(string url, string adapterType, CancellationToken ct = default)
+    {
+        if (!Uri.TryCreate(url, UriKind.Absolute, out var uri))
+        {
+            _logger.LogWarning("[{Channel}] Invalid source URL passed for discovery: {Url}", "NewsChannel", url);
+            return null;
+        }
+
+        try
+        {
+            _logger.LogDebug("Fetching content from discovery source: {Url}", uri);
+            var content = await _httpClient.GetStringAsync(uri, ct);
+
+            if (string.IsNullOrWhiteSpace(content)) return [];
+
+            var trimmedContent = content.TrimStart();
+
+            // 1. Zuerst gezielt nach registriertem Adapter suchen (z. B. finanznachrichten_rss)
+            var adapter = _adapters.FirstOrDefault(a => 
+                a.Name.Equals(adapterType, StringComparison.OrdinalIgnoreCase) || 
+                uri.Host.Contains(a.Name, StringComparison.OrdinalIgnoreCase));
+
+            if (adapter != null)
+            {
+                _logger.LogInformation("[{Channel}] Using specialized adapter {AdapterName} for source: {Url}", "NewsChannel", adapter.Name, url);
+                return adapter.ExtractUrls(content, url);
+            }
+
+            // 2. Fallback: Automatische Erkennung für generische RSS/Atom-Feeds
+            if (adapterType.Equals("rss", StringComparison.OrdinalIgnoreCase) || 
+                trimmedContent.StartsWith("<?xml", StringComparison.OrdinalIgnoreCase) ||
+                trimmedContent.StartsWith("<rss", StringComparison.OrdinalIgnoreCase) ||
+                trimmedContent.StartsWith("<feed", StringComparison.OrdinalIgnoreCase))
+            {
+                _logger.LogInformation("[{Channel}] Syndication (RSS) format detected for source: {Url}", "NewsChannel", url);
+                
+                var rssAdapter = _adapters.FirstOrDefault(a => a.Name.Equals("rss", StringComparison.OrdinalIgnoreCase)) 
+                                 ?? new RssDiscoveryAdapter();
+
+                return rssAdapter.ExtractUrls(content, url);
+            }
+
+            _logger.LogWarning("[{Channel}] No suitable discovery adapter found for type '{Type}' and URL: {Url}", "NewsChannel", adapterType, url);
+            return [];
+        }
+        catch (Exception ex)
+        {
+            _logger.LogError(ex, "[{Channel}] Failed to run article discovery on URL: {Url}", "NewsChannel", url);
+            return [];
+        }
+    }
+}