add selector

ratings/selector/src/commonMain/kotlin/DefaultSelector.kt

@@ -0,0 +1,21 @@
+package dev.inmo.plaguposter.ratings.selector
+
+import dev.inmo.plaguposter.posts.models.PostId
+import dev.inmo.plaguposter.ratings.repo.RatingsRepo
+import dev.inmo.plaguposter.ratings.selector.models.SelectorConfig
+
+class DefaultSelector (
+    private val config: SelectorConfig,
+    private val repo: RatingsRepo
+) : Selector {
+    override suspend fun take(n: Int): List<PostId> {
+        val result = mutableListOf<PostId>()
+
+        do {
+            val selected = config.active ?.ratings ?.select(repo, result) ?: break
+            result.add(selected)
+        } while (result.size < n)
+
+        return result.toList()
+    }
+}