feat: build v1 Mews client: reader UI, gestures, Drift store, fetch actor

app/lib/database/database.dart

@@ -0,0 +1,157 @@
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:drift/drift.dart';
+import 'package:drift/native.dart';
+import 'package:path/path.dart' as p;
+import 'package:path_provider/path_provider.dart';
+
+part 'database.g.dart';
+
+/// Visited pages, newest first; the most recent row is the app's start page.
+class HistoryItems extends Table {
+  IntColumn get id => integer().autoIncrement()();
+  TextColumn get url => text()();
+  TextColumn get title => text().nullable()();
+  DateTimeColumn get visitedAt => dateTime().withDefault(currentDateAndTime)();
+}
+
+class Bookmarks extends Table {
+  IntColumn get id => integer().autoIncrement()();
+  TextColumn get url => text()();
+  TextColumn get title => text().nullable()();
+  DateTimeColumn get createdAt => dateTime().withDefault(currentDateAndTime)();
+}
+
+/// A subscription to one page (spec 6). [entryUrls] is a JSON list of the
+/// entry URLs already seen, so a refresh can report only new posts.
+class Subscriptions extends Table {
+  IntColumn get id => integer().autoIncrement()();
+  TextColumn get url => text()();
+  TextColumn get title => text().nullable()();
+  TextColumn get entryUrls => text().withDefault(const Constant('[]'))();
+  DateTimeColumn get createdAt => dateTime().withDefault(currentDateAndTime)();
+  DateTimeColumn get lastCheckedAt => dateTime().nullable()();
+}
+
+/// Single-row table (id 0) holding the reader's presentation choices.
+class ReaderSettings extends Table {
+  IntColumn get id => integer().withDefault(const Constant(0))();
+  TextColumn get font => text().withDefault(const Constant('Atkinson Hyperlegible'))();
+  RealColumn get fontScale => real().withDefault(const Constant(1.0))();
+  TextColumn get themeMode => text().withDefault(const Constant('system'))();
+  TextColumn get variant => text().withDefault(const Constant('site'))();
+
+  @override
+  Set<Column> get primaryKey => {id};
+}
+
+/// The fetched source of a page, kept so the reader can reopen it offline.
+class CachedPages extends Table {
+  TextColumn get url => text()();
+  TextColumn get title => text().nullable()();
+  TextColumn get source => text()();
+  TextColumn get etag => text().nullable()();
+  TextColumn get lastModified => text().nullable()();
+  DateTimeColumn get cachedAt => dateTime().withDefault(currentDateAndTime)();
+
+  @override
+  Set<Column> get primaryKey => {url};
+}
+
+@DriftDatabase(tables: [HistoryItems, Bookmarks, Subscriptions, ReaderSettings, CachedPages])
+class MewsDatabase extends _$MewsDatabase {
+  MewsDatabase() : super(_open());
+
+  /// For tests.
+  MewsDatabase.test(super.executor);
+
+  @override
+  int get schemaVersion => 1;
+
+  static QueryExecutor _open() => LazyDatabase(() async {
+        final dir = await getApplicationDocumentsDirectory();
+        return NativeDatabase.createInBackground(File(p.join(dir.path, 'mews.sqlite')));
+      });
+
+  // History -------------------------------------------------------------
+
+  Future<void> recordVisit(String url, String? title) =>
+      (into(historyItems).insert(HistoryItemsCompanion.insert(url: url, title: Value(title))));
+
+  Future<String?> lastVisitedUrl() async {
+    final query = (select(historyItems)
+          ..orderBy([
+            (r) => OrderingTerm.desc(r.visitedAt),
+            // Tiebreak pages recorded within the same clock tick.
+            (r) => OrderingTerm.desc(r.id),
+          ])
+          ..limit(1));
+    final row = await query.getSingleOrNull();
+    return row?.url;
+  }
+
+  // Bookmarks -----------------------------------------------------------
+
+  Future<List<Bookmark>> allBookmarks() => select(bookmarks).get();
+
+  Future<void> addBookmark(String url, String? title) => into(bookmarks).insert(
+      BookmarksCompanion.insert(url: url, title: Value(title)),
+      mode: InsertMode.insertOrIgnore);
+
+  Future<void> removeBookmark(String url) =>
+      (delete(bookmarks)..where((r) => r.url.equals(url))).go();
+
+  // Subscriptions ---------------------------------------------------------
+
+  Future<void> addSubscription(String url, String? title, List<String> entryUrls) => into(
+          subscriptions)
+      .insert(
+          SubscriptionsCompanion.insert(
+              url: url, title: Value(title), entryUrls: Value(jsonEncode(entryUrls))),
+          mode: InsertMode.insertOrIgnore);
+
+  Future<void> removeSubscription(String url) =>
+      (delete(subscriptions)..where((r) => r.url.equals(url))).go();
+
+  Future<List<Subscription>> allSubscriptions() => select(subscriptions).get();
+
+  Future<void> updateSubscription(String url,
+          {String? title, List<String>? entryUrls, DateTime? lastCheckedAt}) =>
+      (update(subscriptions)..where((r) => r.url.equals(url))).write(SubscriptionsCompanion(
+            title: Value(title),
+            entryUrls: entryUrls == null ? const Value.absent() : Value(jsonEncode(entryUrls)),
+            lastCheckedAt: Value(lastCheckedAt),
+          ));
+
+  // Settings ---------------------------------------------------------------
+
+  Future<ReaderSetting?> readSettings() async {
+    final query = select(readerSettings)..where((r) => r.id.equals(0));
+    return query.getSingleOrNull();
+  }
+
+  Future<void> saveSettings({
+    required String font,
+    required double fontScale,
+    required String themeMode,
+    required String variant,
+  }) =>
+      into(readerSettings).insert(
+          ReaderSettingsCompanion.insert(
+            id: const Value(0),
+            font: Value(font),
+            fontScale: Value(fontScale),
+            themeMode: Value(themeMode),
+            variant: Value(variant),
+          ),
+          mode: InsertMode.insertOrReplace);
+
+  // Cache --------------------------------------------------------------------
+
+  Future<CachedPage?> cachedPage(String url) async =>
+      (select(cachedPages)..where((r) => r.url.equals(url))).getSingleOrNull();
+
+  Future<void> saveCachedPage(CachedPagesCompanion entry) =>
+      into(cachedPages).insert(entry, mode: InsertMode.insertOrReplace);
+}