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diff --git a/icing/result/result-retriever-v2.h b/icing/result/result-retriever-v2.h
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+// Copyright (C) 2022 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef ICING_RESULT_RETRIEVER_V2_H_
+#define ICING_RESULT_RETRIEVER_V2_H_
+
+#include <memory>
+#include <unordered_map>
+#include <utility>
+#include <vector>
+
+#include "icing/text_classifier/lib3/utils/base/statusor.h"
+#include "icing/result/page-result.h"
+#include "icing/result/result-state-v2.h"
+#include "icing/result/snippet-retriever.h"
+#include "icing/schema/schema-store.h"
+#include "icing/scoring/scored-document-hit.h"
+#include "icing/store/document-store.h"
+#include "icing/store/namespace-id.h"
+#include "icing/tokenization/language-segmenter.h"
+#include "icing/transform/normalizer.h"
+
+namespace icing {
+namespace lib {
+
+class GroupResultLimiterV2 {
+ public:
+  GroupResultLimiterV2() {}
+
+  virtual ~GroupResultLimiterV2() = default;
+
+  // Returns true if the scored_document_hit should be removed.
+  virtual bool ShouldBeRemoved(
+      const ScoredDocumentHit& scored_document_hit,
+      const std::unordered_map<NamespaceId, int>& namespace_group_id_map,
+      const DocumentStore& document_store,
+      std::vector<int>& group_result_limits) const;
+};
+
+class ResultRetrieverV2 {
+ public:
+  // Factory function to create a ResultRetrieverV2 which does not take
+  // ownership of any input components, and all pointers must refer to valid
+  // objects that outlive the created ResultRetrieverV2 instance.
+  //
+  // Returns:
+  //   A ResultRetrieverV2 on success
+  //   FAILED_PRECONDITION on any null pointer input
+  static libtextclassifier3::StatusOr<std::unique_ptr<ResultRetrieverV2>>
+  Create(const DocumentStore* doc_store, const SchemaStore* schema_store,
+         const LanguageSegmenter* language_segmenter,
+         const Normalizer* normalizer,
+         std::unique_ptr<const GroupResultLimiterV2> group_result_limiter =
+             std::make_unique<const GroupResultLimiterV2>());
+
+  // Retrieves results (pairs of DocumentProtos and SnippetProtos) with the
+  // given ResultState which holds document and snippet information. It pulls
+  // out the next top rank documents from ResultState, retrieves the documents
+  // from storage, updates ResultState, and finally wraps the result + other
+  // information into PageResult. The expected number of documents to return is
+  // min(num_per_page, the number of all scored document hits) inside
+  // ResultState.
+  //
+  // The number of snippets to return is based on the total number of snippets
+  // needed and number of snippets that have already been returned previously
+  // for the same query. The order of results returned will be sorted by
+  // scored_document_hit_comparator inside ResultState.
+  //
+  // An additional boolean value will be returned, indicating if ResultState has
+  // remaining documents to be retrieved next round.
+  //
+  // All errors will be ignored. It will keep retrieving the next document and
+  // valid documents will be included in PageResult.
+  //
+  // Returns:
+  //   std::pair<PageResult, bool>
+  std::pair<PageResult, bool> RetrieveNextPage(
+      ResultStateV2& result_state) const;
+
+ private:
+  explicit ResultRetrieverV2(
+      const DocumentStore* doc_store,
+      std::unique_ptr<SnippetRetriever> snippet_retriever,
+      std::unique_ptr<const GroupResultLimiterV2> group_result_limiter)
+      : doc_store_(*doc_store),
+        snippet_retriever_(std::move(snippet_retriever)),
+        group_result_limiter_(std::move(group_result_limiter)) {}
+
+  const DocumentStore& doc_store_;
+  std::unique_ptr<SnippetRetriever> snippet_retriever_;
+  const std::unique_ptr<const GroupResultLimiterV2> group_result_limiter_;
+};
+
+}  // namespace lib
+}  // namespace icing
+
+#endif  // ICING_RESULT_RETRIEVER_V2_H_