Updated on 2026-08-14

core/datasource/src/main/java/com/tangem/datasource/di/NewsStoreModule.kt

@@ -5,6 +5,8 @@ import com.tangem.datasource.local.news.details.DefaultNewsDetailsStore
 import com.tangem.datasource.local.news.details.NewsDetailsStore
 import com.tangem.datasource.local.news.trending.DefaultTrendingNewsStore
 import com.tangem.datasource.local.news.trending.TrendingNewsStore
+import com.tangem.datasource.local.news.viewed.DefaultNewsViewedStore
+import com.tangem.datasource.local.news.viewed.NewsViewedStore
 import dagger.Module
 import dagger.Provides
 import dagger.hilt.InstallIn
@@ -26,4 +28,10 @@ internal object NewsStoreModule {
     fun provideTrendingNewsStore(): TrendingNewsStore {
         return DefaultTrendingNewsStore(store = RuntimeSharedStore())
     }
+
+    @Provides
+    @Singleton
+    fun provideNewsViewedStore(): NewsViewedStore {
+        return DefaultNewsViewedStore(store = RuntimeSharedStore())
+    }
 }

core/datasource/src/main/java/com/tangem/datasource/local/news/viewed/DefaultNewsViewedStore.kt

@@ -0,0 +1,32 @@
+package com.tangem.datasource.local.news.viewed
+
+import com.tangem.datasource.local.datastore.RuntimeSharedStore
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.onStart
+
+private typealias NewsViewedCache = Map<Int, Boolean>
+
+internal class DefaultNewsViewedStore(
+    private val store: RuntimeSharedStore<NewsViewedCache>,
+) : NewsViewedStore {
+
+    override fun getAll(): Flow<Map<Int, Boolean>> {
+        return store.get().onStart { emit(emptyMap()) }
+    }
+
+    override suspend fun getSync(): Map<Int, Boolean> {
+        return store.getSyncOrNull().orEmpty()
+    }
+
+    override suspend fun updateViewed(articleIds: Collection<Int>, viewed: Boolean) {
+        if (articleIds.isEmpty()) return
+
+        store.update(emptyMap()) { current ->
+            val updated = current.toMutableMap()
+            articleIds.forEach { id ->
+                updated[id] = viewed
+            }
+            updated
+        }
+    }
+}

core/datasource/src/main/java/com/tangem/datasource/local/news/viewed/NewsViewedStore.kt

@@ -0,0 +1,24 @@
+package com.tangem.datasource.local.news.viewed
+
+import kotlinx.coroutines.flow.Flow
+
+/**
+ * Store for news viewed flags (runtime only).
+ */
+interface NewsViewedStore {
+
+    /**
+     * Observes all viewed flags.
+     */
+    fun getAll(): Flow<Map<Int, Boolean>>
+
+    /**
+     * Gets viewed flags synchronously (returns empty map if no data).
+     */
+    suspend fun getSync(): Map<Int, Boolean>
+
+    /**
+     * Updates viewed flags for provided article ids.
+     */
+    suspend fun updateViewed(articleIds: Collection<Int>, viewed: Boolean)
+}