Refactor project structure and enhance stock watchlist functionality

lib/services/duriin_service.dart

@@ -0,0 +1,117 @@
+import 'dart:convert';
+
+import 'package:capstone_project/utils/agrigator.dart';
+import 'package:http/http.dart' as http;
+
+
+const _baseUrl = 'http://duriin.imbenji.net';
+
+
+// pair of (article, semantic distance from the query / seed). distance is
+// null when the underlying endpoint doesnt return one.
+class SimilarHit {
+  final FeedItem item;
+  final double? distance;
+
+  SimilarHit({required this.item, this.distance});
+}
+
+
+class DuriinService {
+
+  Future<List<FeedItem>> search({
+    required String ticker,
+    required String companyName,
+    required DateTime from,
+    required DateTime to,
+    int limit = 100,
+  }) async {
+    final fromStr = from.toUtc().toIso8601String();
+    final toStr = to.toUtc().toIso8601String();
+
+
+    // build the keyword set: the ticker itself plus the company brand name
+    // (first token of the registered name — "NVIDIA Corporation" -> "NVIDIA",
+    // "Apple Inc" -> "Apple"). the full legal name rarely appears verbatim in
+    // articles so matching on it would miss most hits.
+    final keywords = <String>{};
+    final t = ticker.trim();
+    if (t.isNotEmpty) keywords.add(t);
+
+    final brand = companyName.trim().split(RegExp(r"\s+")).firstOrNull ?? "";
+    if (brand.isNotEmpty) keywords.add(brand);
+
+    final hits = await _fetchHits(queryParams: {
+      'keyword': keywords.toList(),
+      'keyword_mode': 'or',
+      'from': fromStr,
+      'to': toStr,
+      'limit': '$limit',
+      'order': 'newest',
+    });
+
+    final items = hits.map((h) => h.item).toList();
+
+    print('Duriin: ${items.length} articles for $ticker / $companyName (kw=${keywords.join(",")})');
+    return items;
+  }
+
+
+  // neighbours of a given article via the vector index. used by the event
+  // clusterer to build real clusters instead of arbitrary time slices.
+  Future<List<SimilarHit>> findSimilar(int articleId, {int limit = 25}) async {
+    return _fetchHits(queryParams: {
+      'similar_to_article': '$articleId',
+      'limit': '$limit',
+    });
+  }
+
+
+  Future<List<SimilarHit>> _fetchHits({required Map<String, dynamic> queryParams}) async {
+    final uri = Uri.parse(_baseUrl).replace(
+      path: '/articles',
+      queryParameters: queryParams,
+    );
+
+    try {
+      final response = await http.get(uri);
+
+      if (response.statusCode != 200) {
+        print('Duriin: HTTP ${response.statusCode} for $uri');
+        return [];
+      }
+
+      final body = response.body.trim();
+      if (body.isEmpty) return [];
+
+      final list = jsonDecode(body) as List<dynamic>;
+
+      return list.map((raw) {
+        final m = raw as Map<String, dynamic>;
+
+        final id = m['id'] is int
+            ? m['id'] as int
+            : int.tryParse('${m['id']}');
+
+        final item = FeedItem(
+          id: id,
+          title: (m['title'] ?? '').toString(),
+          description: (m['description'] ?? '').toString(),
+          content: (m['content'] ?? '').toString(),
+          link: (m['url'] ?? '').toString(),
+          source: (m['source'] ?? '').toString().isNotEmpty ? m['source'].toString() : null,
+          pubDate: m['pub_date'] != null ? DateTime.tryParse(m['pub_date'].toString()) : null,
+        );
+
+        final distRaw = m['distance'];
+        final distance = distRaw is num ? distRaw.toDouble() : null;
+
+        return SimilarHit(item: item, distance: distance);
+      }).where((h) => h.item.title.isNotEmpty && h.item.link.isNotEmpty).toList();
+
+    } catch (e) {
+      print('Duriin fetch error: $e');
+      return [];
+    }
+  }
+}

lib/services/news_search_service.dart

@@ -0,0 +1,19 @@
+import 'package:capstone_project/services/duriin_service.dart';
+import 'package:capstone_project/utils/agrigator.dart';
+
+
+class NewsSearchService {
+  final _duriin = DuriinService();
+
+  Future<List<FeedItem>> search({
+    required String ticker,
+    required String companyName,
+    required DateTime from,
+    required DateTime to,
+  }) => _duriin.search(
+    ticker: ticker,
+    companyName: companyName,
+    from: from,
+    to: to,
+  );
+}

lib/services/stock_price_service.dart

@@ -0,0 +1,82 @@
+import 'dart:convert';
+
+import 'package:http/http.dart' as http;
+
+class StockPricePoint {
+  final DateTime date;
+  final double close;
+
+  const StockPricePoint({required this.date, required this.close});
+}
+
+class StockPriceService {
+  Future<List<StockPricePoint>> fetchPriceHistory(
+    String ticker, {
+    String range = '1mo',
+    String interval = '1d',
+  }) async {
+    final normalizedTicker = ticker.trim().toUpperCase();
+    final uri = Uri.parse(
+      'https://query1.finance.yahoo.com/v8/finance/chart/$normalizedTicker?interval=$interval&range=$range',
+    );
+
+    final response = await http.get(uri, headers: {
+      'User-Agent': 'Mozilla/5.0',
+      'Accept': 'application/json',
+    });
+
+    if (response.statusCode != 200) {
+      throw Exception('Failed to fetch price history for $normalizedTicker: ${response.statusCode}');
+    }
+
+    final json = jsonDecode(response.body) as Map<String, dynamic>;
+    final chart = json['chart'] as Map<String, dynamic>?;
+    final results = chart?['result'] as List?;
+
+    if (results == null || results.isEmpty) {
+      throw Exception('No price history returned for $normalizedTicker');
+    }
+
+    final result = results.first as Map<String, dynamic>;
+    final timestamps = (result['timestamp'] as List?) ?? const [];
+    final indicators = result['indicators'] as Map<String, dynamic>?;
+    final adjCloseSeries = ((indicators?['adjclose'] as List?) ?? const [])
+        .cast<Map<String, dynamic>?>();
+    final quoteSeries = ((indicators?['quote'] as List?) ?? const [])
+        .cast<Map<String, dynamic>?>();
+
+    final adjCloseEntry = adjCloseSeries.isNotEmpty ? adjCloseSeries.first : null;
+    final quoteEntry = quoteSeries.isNotEmpty ? quoteSeries.first : null;
+    final adjCloseValues = adjCloseEntry == null ? null : adjCloseEntry['adjclose'];
+    final quoteCloseValues = quoteEntry == null ? null : quoteEntry['close'];
+    final closes = (adjCloseValues as List?) ?? (quoteCloseValues as List?) ?? const [];
+
+    final points = <StockPricePoint>[];
+    final itemCount = timestamps.length < closes.length ? timestamps.length : closes.length;
+
+    for (int i = 0; i < itemCount; i++) {
+      final timestamp = timestamps[i];
+      final close = closes[i];
+
+      if (timestamp is! num || close is! num) {
+        continue;
+      }
+
+      points.add(
+        StockPricePoint(
+          date: DateTime.fromMillisecondsSinceEpoch(
+            timestamp.toInt() * 1000,
+            isUtc: true,
+          ).toLocal(),
+          close: close.toDouble(),
+        ),
+      );
+    }
+
+    if (points.isEmpty) {
+      throw Exception('No valid price points returned for $normalizedTicker');
+    }
+
+    return points;
+  }
+}