// Copyright 2023 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "components/browsing_topics/common/semantic_tree.h"

#include <optional>

#include "base/strings/string_number_conversions.h"
#include "base/test/gtest_util.h"
#include "base/test/scoped_feature_list.h"
#include "components/browsing_topics/common/common_types.h"
#include "components/strings/grit/components_strings.h"
#include "third_party/blink/public/common/features.h"

namespace browsing_topics {

class SemanticTreeUnittest : public testing::Test {
 protected:
  SemanticTree semantic_tree_;
};

TEST_F(SemanticTreeUnittest, GetRandomTopic_ValidInput) {
  Topic topic = semantic_tree_.GetRandomTopic(1, 3);
  EXPECT_EQ(topic, Topic(4));
}

TEST_F(SemanticTreeUnittest, GetRandomTopic_ZeroSeedIsValid) {
  Topic topic = semantic_tree_.GetRandomTopic(1, 0);
  EXPECT_EQ(topic, Topic(1));
}

TEST_F(SemanticTreeUnittest, GetRandomTopic_SeedIsHigherThanTaxonomySize) {
  Topic topic = semantic_tree_.GetRandomTopic(1, 400);
  EXPECT_EQ(topic, Topic(52));
}

TEST_F(SemanticTreeUnittest, GetRandomTopic_InvalidTaxonomyVersion) {
  EXPECT_CHECK_DEATH(semantic_tree_.GetRandomTopic(10, 400));
}

TEST_F(SemanticTreeUnittest, GetRandomTopic_NotInitialTaxonomy) {
  Topic topic = semantic_tree_.GetRandomTopic(2, 3);
  // Because topics 2,3,5-8,10,11 are deleted, topic 12 is the 4th topic in
  // taxonomy 2.
  EXPECT_EQ(topic, Topic(12));
}

TEST_F(SemanticTreeUnittest, IsTaxonomySupported_ValidTaxonomyVersion) {
  EXPECT_TRUE(semantic_tree_.IsTaxonomySupported(1));
}

TEST_F(SemanticTreeUnittest, IsTaxonomySupported_InvalidTaxonomyVersion) {
  EXPECT_FALSE(semantic_tree_.IsTaxonomySupported(0));
  EXPECT_FALSE(semantic_tree_.IsTaxonomySupported(100));
}

TEST_F(SemanticTreeUnittest, GetDescendantTopicsTopicNotInMap) {
  std::vector<Topic> topics = semantic_tree_.GetDescendantTopics(Topic(10000));
  EXPECT_TRUE(topics.empty());
}

TEST_F(SemanticTreeUnittest, GetDescendantTopicsNoChildren) {
  std::vector<Topic> topics = semantic_tree_.GetDescendantTopics(Topic(8));
  EXPECT_TRUE(topics.empty());
}

TEST_F(SemanticTreeUnittest, GetDescendantTopicsOneChild) {
  std::vector<Topic> topics = semantic_tree_.GetDescendantTopics(Topic(7));
  std::vector<Topic> expected_descendants = {Topic(8)};
  EXPECT_EQ(topics, expected_descendants);
}

TEST_F(SemanticTreeUnittest, GetDescendantTopicsMultipleChildren) {
  std::vector<Topic> topics = semantic_tree_.GetDescendantTopics(Topic(250));
  std::vector<Topic> expected_descendants = {Topic(251), Topic(252),
                                             Topic(253)};
  EXPECT_EQ(topics, expected_descendants);
}

TEST_F(SemanticTreeUnittest, GetDescendantTopicsMultipleLevelsOfDescendants) {
  std::vector<Topic> topics = semantic_tree_.GetDescendantTopics(Topic(255));
  std::vector<Topic> expected_descendants = {Topic(256), Topic(257), Topic(258),
                                             Topic(259), Topic(260), Topic(261),
                                             Topic(563)};
  EXPECT_EQ(topics, expected_descendants);
}

TEST_F(SemanticTreeUnittest, GetAncestorTopicsTopicNotInMap) {
  std::vector<Topic> topics = semantic_tree_.GetAncestorTopics(Topic(10000));
  EXPECT_TRUE(topics.empty());
}

TEST_F(SemanticTreeUnittest, GetAncestorTopicsNoAncestors) {
  std::vector<Topic> topics = semantic_tree_.GetAncestorTopics(Topic(1));
  EXPECT_TRUE(topics.empty());
}

TEST_F(SemanticTreeUnittest, GetAncestorTopicsOneAncestor) {
  std::vector<Topic> topics = semantic_tree_.GetAncestorTopics(Topic(2));
  EXPECT_FALSE(topics.empty());
  std::vector<Topic> expected_ancestors = {Topic(1)};
  EXPECT_EQ(topics, expected_ancestors);
}

TEST_F(SemanticTreeUnittest, GetAncestorTopicsMultipleAncestors) {
  std::vector<Topic> topics = semantic_tree_.GetAncestorTopics(Topic(36));
  EXPECT_FALSE(topics.empty());
  std::vector<Topic> expected_ancestors = {Topic(1), Topic(23), Topic(33)};
  EXPECT_EQ(topics, expected_ancestors);
}

TEST_F(SemanticTreeUnittest, GetAncestorTopicsMultipleParents) {
  std::vector<Topic> topics = semantic_tree_.GetAncestorTopics(Topic(277));
  EXPECT_FALSE(topics.empty());
  std::vector<Topic> expected_ancestors = {Topic(226), Topic(227), Topic(275)};
  EXPECT_EQ(topics, expected_ancestors);
}

TEST_F(SemanticTreeUnittest, GetAncestorTopicsMaximumTopic) {
  std::vector<Topic> topics =
      semantic_tree_.GetAncestorTopics(Topic(SemanticTree::kNumTopics));
  EXPECT_FALSE(topics.empty());
  std::vector<Topic> expected_ancestors = {Topic(332), Topic(626)};
  EXPECT_EQ(topics, expected_ancestors);
}

TEST_F(SemanticTreeUnittest, GetLatestLocalizedNameMessageIdValidTopic) {
  std::optional<int> message_id =
      semantic_tree_.GetLatestLocalizedNameMessageId(Topic(100));
  EXPECT_EQ(message_id.value(),
            IDS_PRIVACY_SANDBOX_TOPICS_TAXONOMY_V1_TOPIC_ID_100);
}

TEST_F(SemanticTreeUnittest, GetLatestLocalizedNameMessageIdAddedTopic) {
  std::optional<int> message_id =
      semantic_tree_.GetLatestLocalizedNameMessageId(Topic(363));
  EXPECT_EQ(message_id.value(),
            IDS_PRIVACY_SANDBOX_TOPICS_TAXONOMY_V2_TOPIC_ID_363);
}

TEST_F(SemanticTreeUnittest, GetLatestLocalizedNameMessageIdMaximumTopic) {
  std::optional<int> message_id =
      semantic_tree_.GetLatestLocalizedNameMessageId(
          Topic(SemanticTree::kNumTopics));
  EXPECT_EQ(message_id.value(),
            IDS_PRIVACY_SANDBOX_TOPICS_TAXONOMY_V2_TOPIC_ID_629);
}

TEST_F(SemanticTreeUnittest, GetLatestLocalizedNameMessageIdInvalidTaxonomy) {
  base::test::ScopedFeatureList feature_list;
  feature_list.InitAndEnableFeatureWithParameters(
      blink::features::kBrowsingTopicsParameters, {{"taxonomy_version", "0"}});
  std::optional<int> message_id =
      semantic_tree_.GetLatestLocalizedNameMessageId(Topic(100));
  EXPECT_FALSE(message_id.has_value());
}

TEST_F(SemanticTreeUnittest, GetLatestLocalizedNameMessageIdInvalidTopic) {
  std::optional<int> message_id =
      semantic_tree_.GetLatestLocalizedNameMessageId(Topic(9999));
  EXPECT_FALSE(message_id.has_value());
}

TEST_F(SemanticTreeUnittest, GetFirstLevelTopic) {
  const size_t kFirstLevelTopicsV2Size = 22;

  base::test::ScopedFeatureList feature_list;
  feature_list.InitAndEnableFeatureWithParameters(
      blink::features::kBrowsingTopicsParameters, {{"taxonomy_version", "2"}});
  std::vector<Topic> first_level_topics =
      semantic_tree_.GetFirstLevelTopicsInCurrentTaxonomy();
  EXPECT_EQ(std::size(first_level_topics), kFirstLevelTopicsV2Size);
}

TEST_F(SemanticTreeUnittest, GetFirstLevelTopicsSizeNotReturningDeletedTopics) {
  base::test::ScopedFeatureList feature_list;
  feature_list.InitAndEnableFeatureWithParameters(
      blink::features::kBrowsingTopicsParameters, {{"taxonomy_version", "2"}});
  std::vector<Topic> first_level_topics =
      semantic_tree_.GetFirstLevelTopicsInCurrentTaxonomy();
  std::set<Topic> first_level_topics_set(std::begin(first_level_topics),
                                         std::end(first_level_topics));

  const Topic kFirstLevelV2DeletedTopic = Topic(275);
  EXPECT_FALSE(first_level_topics_set.contains(kFirstLevelV2DeletedTopic));
}

TEST_F(SemanticTreeUnittest, GetAtMostTwoRepresentativesReturnsCorrectTopics) {
  base::test::ScopedFeatureList feature_list;
  feature_list.InitAndEnableFeatureWithParameters(
      blink::features::kBrowsingTopicsParameters, {{"taxonomy_version", "2"}});

  std::vector<Topic> representatives =
      semantic_tree_.GetAtMostTwoRepresentativesInCurrentTaxonomy(Topic(126));

  EXPECT_EQ(std::size(representatives), 2u);

  representatives =
      semantic_tree_.GetAtMostTwoRepresentativesInCurrentTaxonomy(Topic(250));

  EXPECT_EQ(std::size(representatives), 1u);

  representatives = semantic_tree_.GetAtMostTwoRepresentativesInCurrentTaxonomy(
      Topic(999999));
  EXPECT_EQ(std::size(representatives), 0u);

  representatives =
      semantic_tree_.GetAtMostTwoRepresentativesInCurrentTaxonomy(Topic(275));
  EXPECT_EQ(std::size(representatives), 0u);
}

TEST_F(SemanticTreeUnittest, RepresentativesNeverEmptyForFirstLevelTopics) {
  base::test::ScopedFeatureList feature_list;

  for (int version = 1; version <= SemanticTree::kMaxTaxonomyVersion;
       version++) {
    feature_list.Reset();
    feature_list.InitAndEnableFeatureWithParameters(
        blink::features::kBrowsingTopicsParameters,
        {{"taxonomy_version", base::NumberToString(version)}});
    std::vector<Topic> first_level_topics =
        semantic_tree_.GetFirstLevelTopicsInCurrentTaxonomyInternal();

    for (auto topic : first_level_topics) {
      EXPECT_FALSE(
          semantic_tree_.GetAtMostTwoRepresentativesInCurrentTaxonomy(topic)
              .empty());
    }
  }
}

TEST_F(SemanticTreeUnittest, RepresentativesAreTopicsInTheCurrentTaxonomy) {
  std::vector<Topic> first_level_topics =
      semantic_tree_.GetFirstLevelTopicsInCurrentTaxonomyInternal();

  for (auto topic : first_level_topics) {
    auto representatives =
        semantic_tree_.GetAtMostTwoRepresentativesInCurrentTaxonomy(topic);
    auto topics_in_current_taxonomy =
        semantic_tree_.GetTopicsInCurrentTaxonomyInternal();

    for (auto representative : representatives) {
      EXPECT_TRUE(topics_in_current_taxonomy.contains(representative.value()));
    }
  }
}

}  // namespace browsing_topics