feat(app): 剧场页九宫格与极简我的页

lib/pages/discover/ranking_logic.dart

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+// Author: fruit.com.cn
+
+import 'package:flutter/foundation.dart';
+
+import '../../core/data/models/drama.dart';
+import '../../core/data/models/home_feed.dart';
+
+/// Ranking boards backed by the feed sections the server already returns.
+enum RankingBoard { hot, newReleases }
+
+/// One ranked title; rank is one-based and mirrors server section order.
+class RankingEntry {
+  const RankingEntry({required this.rank, required this.drama});
+
+  final int rank;
+  final Drama drama;
+}
+
+/// Keeps the active board and turns real feed sections into ranked entries.
+///
+/// The backend does not expose a dedicated ranking endpoint, so this class
+/// never invents scores: it preserves the order of the `hot` and `new`
+/// sections and only falls back to the catalog when a section is absent.
+class RankingLogic extends ChangeNotifier {
+  RankingLogic({required this.sections, required this.fallback});
+
+  static const hotSectionCode = 'hot';
+  static const newSectionCode = 'new';
+
+  List<FeedSection> sections;
+  List<Drama> fallback;
+  RankingBoard _board = RankingBoard.hot;
+
+  RankingBoard get board => _board;
+
+  List<RankingEntry> get entries {
+    final sectionCode = _board == RankingBoard.hot
+        ? hotSectionCode
+        : newSectionCode;
+    final source = _sectionDramas(sectionCode);
+    final dramas = source.isEmpty ? fallback : source;
+    final seen = <String>{};
+    final unique = [
+      for (final drama in dramas)
+        if (seen.add(drama.id)) drama,
+    ];
+    return [
+      for (var index = 0; index < unique.length; index++)
+        RankingEntry(rank: index + 1, drama: unique[index]),
+    ];
+  }
+
+  /// Switches boards and notifies only when the visible source changes.
+  void select(RankingBoard next) {
+    if (_board == next) return;
+    _board = next;
+    notifyListeners();
+  }
+
+  /// Applies refreshed feed data without rebuilding the page state.
+  void updateSources({
+    required List<FeedSection> sections,
+    required List<Drama> fallback,
+  }) {
+    this.sections = sections;
+    this.fallback = fallback;
+    notifyListeners();
+  }
+
+  List<Drama> _sectionDramas(String code) {
+    for (final section in sections) {
+      if (section.code == code) return section.dramas;
+    }
+    return const [];
+  }
+}