Add TitledUrlIndex for indexing arbitrary title/URL pairs

components/bookmarks/browser/bookmark_index.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/bookmarks/browser/bookmark_index.h"
 
 #include <stdint.h>
 
-#include <algorithm>
-#include <functional>
-#include <iterator>
-#include <list>
-
 #include "base/i18n/case_conversion.h"
 #include "base/logging.h"
 #include "base/stl_util.h"
 #include "base/strings/utf_offset_string_conversions.h"
 #include "build/build_config.h"
-#include "components/bookmarks/browser/bookmark_client.h"
 #include "components/bookmarks/browser/bookmark_match.h"
-#include "components/bookmarks/browser/bookmark_node.h"
 #include "components/bookmarks/browser/bookmark_utils.h"
+#include "components/bookmarks/browser/titled_url_node.h"
+#include "components/bookmarks/browser/titled_url_node_sorter.h"
 #include "components/query_parser/snippet.h"
 #include "third_party/icu/source/common/unicode/normalizer2.h"
 #include "third_party/icu/source/common/unicode/utypes.h"
 
 namespace bookmarks {
 
-typedef BookmarkClient::NodeTypedCountPair NodeTypedCountPair;
-typedef BookmarkClient::NodeTypedCountPairs NodeTypedCountPairs;
-
 namespace {
 
 // Returns a normalized version of the UTF16 string |text|.  If it fails to
 // normalize the string, returns |text| itself as a best-effort.
 base::string16 Normalize(const base::string16& text) {
   UErrorCode status = U_ZERO_ERROR;
   const icu::Normalizer2* normalizer2 =
       icu::Normalizer2::getInstance(nullptr, "nfkc", UNORM2_COMPOSE, status);
   if (U_FAILURE(status)) {
     // Log and crash right away to capture the error code in the crash report.
     LOG(FATAL) << "failed to create a normalizer: " << u_errorName(status);
   }
   icu::UnicodeString unicode_text(
       text.data(), static_cast<int32_t>(text.length()));
   icu::UnicodeString unicode_normalized_text;
   normalizer2->normalize(unicode_text, unicode_normalized_text, status);
   if (U_FAILURE(status)) {
     // This should not happen. Log the error and fall back.
     LOG(ERROR) << "normalization failed: " << u_errorName(status);
     return text;
   }
   return base::string16(unicode_normalized_text.getBuffer(),
                         unicode_normalized_text.length());
 }
 
-// Sort functor for NodeTypedCountPairs. We sort in decreasing order of typed
-// count so that the best matches will always be added to the results.
-struct NodeTypedCountPairSortFunctor {
-  bool operator()(const NodeTypedCountPair& a,
-                  const NodeTypedCountPair& b) const {
-    return a.second > b.second;
-  }
-};
-
-// Extract the const Node* stored in a BookmarkClient::NodeTypedCountPair.
-struct NodeTypedCountPairExtractNodeFunctor {
-  const BookmarkNode* operator()(const NodeTypedCountPair& pair) const {
-    return pair.first;
-  }
-};
-
 }  // namespace
 
-BookmarkIndex::BookmarkIndex(BookmarkClient* client)
-    : client_(client) {
-  DCHECK(client_);
+BookmarkIndex::BookmarkIndex(std::unique_ptr<TitledUrlNodeSorter> sorter)
+    : sorter_(std::move(sorter)) {
 }
 
 BookmarkIndex::~BookmarkIndex() {
 }
 
-void BookmarkIndex::Add(const BookmarkNode* node) {
-  if (!node->is_url())
+void BookmarkIndex::Add(const TitledUrlNode* node) {
+  if (!node->GetTitledUrlNodeUrl().is_valid())
     return;
   std::vector<base::string16> terms =
-      ExtractQueryWords(Normalize(node->GetTitle()));
+      ExtractQueryWords(Normalize(node->GetTitledUrlNodeTitle()));
   for (size_t i = 0; i < terms.size(); ++i)
     RegisterNode(terms[i], node);
-  terms =
-      ExtractQueryWords(CleanUpUrlForMatching(node->url(), nullptr));
+  terms = ExtractQueryWords(
+      CleanUpUrlForMatching(node->GetTitledUrlNodeUrl(), nullptr));
   for (size_t i = 0; i < terms.size(); ++i)
     RegisterNode(terms[i], node);
 }
 
-void BookmarkIndex::Remove(const BookmarkNode* node) {
-  if (!node->is_url())
+void BookmarkIndex::Remove(const TitledUrlNode* node) {
+  if (!node->GetTitledUrlNodeUrl().is_valid())
     return;
 
   std::vector<base::string16> terms =
-      ExtractQueryWords(Normalize(node->GetTitle()));
+      ExtractQueryWords(Normalize(node->GetTitledUrlNodeTitle()));
   for (size_t i = 0; i < terms.size(); ++i)
     UnregisterNode(terms[i], node);
-  terms =
-      ExtractQueryWords(CleanUpUrlForMatching(node->url(), nullptr));
+  terms = ExtractQueryWords(
+      CleanUpUrlForMatching(node->GetTitledUrlNodeUrl(), nullptr));
   for (size_t i = 0; i < terms.size(); ++i)
     UnregisterNode(terms[i], node);
 }
 
-void BookmarkIndex::GetBookmarksMatching(
+void BookmarkIndex::GetResultsMatching(
     const base::string16& input_query,
     size_t max_count,
     query_parser::MatchingAlgorithm matching_algorithm,
     std::vector<BookmarkMatch>* results) {
   const base::string16 query = Normalize(input_query);
   std::vector<base::string16> terms = ExtractQueryWords(query);
   if (terms.empty())
     return;
 
-  NodeSet matches;
+  TitledUrlNodeSet matches;
   for (size_t i = 0; i < terms.size(); ++i) {
-    if (!GetBookmarksMatchingTerm(
-            terms[i], i == 0, matching_algorithm, &matches)) {
+    if (!GetResultsMatchingTerm(terms[i], i == 0, matching_algorithm,
+                                &matches)) {
       return;
     }
   }
 
-  Nodes sorted_nodes;
+  TitledUrlNodes sorted_nodes;
   SortMatches(matches, &sorted_nodes);
 
   // We use a QueryParser to fill in match positions for us. It's not the most
   // efficient way to go about this, but by the time we get here we know what
   // matches and so this shouldn't be performance critical.
   query_parser::QueryParser parser;
   query_parser::QueryNodeVector query_nodes;
   parser.ParseQueryNodes(query, matching_algorithm, &query_nodes);
 
   // The highest typed counts should be at the beginning of the results vector
   // so that the best matches will always be included in the results. The loop
   // that calculates result relevance in HistoryContentsProvider::ConvertResults
   // will run backwards to assure higher relevance will be attributed to the
   // best matches.
-  for (Nodes::const_iterator i = sorted_nodes.begin();
+  for (TitledUrlNodes::const_iterator i = sorted_nodes.begin();
        i != sorted_nodes.end() && results->size() < max_count;
        ++i)
     AddMatchToResults(*i, &parser, query_nodes, results);
 }
 
-void BookmarkIndex::SortMatches(const NodeSet& matches,
-                                Nodes* sorted_nodes) const {
-  sorted_nodes->reserve(matches.size());
-  if (client_->SupportsTypedCountForNodes()) {
-    NodeTypedCountPairs node_typed_counts;
-    client_->GetTypedCountForNodes(matches, &node_typed_counts);
-    std::sort(node_typed_counts.begin(),
-              node_typed_counts.end(),
-              NodeTypedCountPairSortFunctor());
-    std::transform(node_typed_counts.begin(),
-                   node_typed_counts.end(),
-                   std::back_inserter(*sorted_nodes),
-                   NodeTypedCountPairExtractNodeFunctor());
+void BookmarkIndex::SortMatches(const TitledUrlNodeSet& matches,
+                                TitledUrlNodes* sorted_nodes) const {
+  if (sorter_) {
+    sorter_->SortMatches(matches, sorted_nodes);
   } else {
     sorted_nodes->insert(sorted_nodes->end(), matches.begin(), matches.end());
   }
 }
 
 void BookmarkIndex::AddMatchToResults(
-    const BookmarkNode* node,
+    const TitledUrlNode* node,
     query_parser::QueryParser* parser,
     const query_parser::QueryNodeVector& query_nodes,
     std::vector<BookmarkMatch>* results) {
   // Check that the result matches the query.  The previous search
   // was a simple per-word search, while the more complex matching
   // of QueryParser may filter it out.  For example, the query
-  // ["thi"] will match the bookmark titled [Thinking], but since
+  // ["thi"] will match the title [Thinking], but since
   // ["thi"] is quoted we don't want to do a prefix match.
   query_parser::QueryWordVector title_words, url_words;
   const base::string16 lower_title =
-      base::i18n::ToLower(Normalize(node->GetTitle()));
+      base::i18n::ToLower(Normalize(node->GetTitledUrlNodeTitle()));
   parser->ExtractQueryWords(lower_title, &title_words);
   base::OffsetAdjuster::Adjustments adjustments;
   parser->ExtractQueryWords(
-      CleanUpUrlForMatching(node->url(), &adjustments),
+      CleanUpUrlForMatching(node->GetTitledUrlNodeUrl(), &adjustments),
       &url_words);
   query_parser::Snippet::MatchPositions title_matches, url_matches;
   for (const auto& node : query_nodes) {
     const bool has_title_matches =
         node->HasMatchIn(title_words, &title_matches);
     const bool has_url_matches = node->HasMatchIn(url_words, &url_matches);
     if (!has_title_matches && !has_url_matches)
       return;
     query_parser::QueryParser::SortAndCoalesceMatchPositions(&title_matches);
     query_parser::QueryParser::SortAndCoalesceMatchPositions(&url_matches);
   }
   BookmarkMatch match;
-  if (lower_title.length() == node->GetTitle().length()) {
+  if (lower_title.length() == node->GetTitledUrlNodeTitle().length()) {
     // Only use title matches if the lowercase string is the same length
     // as the original string, otherwise the matches are meaningless.
     // TODO(mpearson): revise match positions appropriately.
     match.title_match_positions.swap(title_matches);
   }
   // Now that we're done processing this entry, correct the offsets of the
   // matches in |url_matches| so they point to offsets in the original URL
   // spec, not the cleaned-up URL string that we used for matching.
   std::vector<size_t> offsets =
       BookmarkMatch::OffsetsFromMatchPositions(url_matches);
   base::OffsetAdjuster::UnadjustOffsets(adjustments, &offsets);
   url_matches =
       BookmarkMatch::ReplaceOffsetsInMatchPositions(url_matches, offsets);
   match.url_match_positions.swap(url_matches);
   match.node = node;
   results->push_back(match);
 }
 
-bool BookmarkIndex::GetBookmarksMatchingTerm(
+bool BookmarkIndex::GetResultsMatchingTerm(
     const base::string16& term,
     bool first_term,
     query_parser::MatchingAlgorithm matching_algorithm,
-    NodeSet* matches) {
+    TitledUrlNodeSet* matches) {
   Index::const_iterator i = index_.lower_bound(term);
   if (i == index_.end())
     return false;
 
   if (!query_parser::QueryParser::IsWordLongEnoughForPrefixSearch(
       term, matching_algorithm)) {
     // Term is too short for prefix match, compare using exact match.
     if (i->first != term)
-      return false;  // No bookmarks with this term.
+      return false;  // No title/URL pairs with this term.
 
     if (first_term) {
       (*matches) = i->second;
       return true;
     }
-    *matches = base::STLSetIntersection<NodeSet>(i->second, *matches);
+    *matches = base::STLSetIntersection<TitledUrlNodeSet>(i->second, *matches);
   } else {
     // Loop through index adding all entries that start with term to
     // |prefix_matches|.
-    NodeSet tmp_prefix_matches;
+    TitledUrlNodeSet tmp_prefix_matches;
     // If this is the first term, then store the result directly in |matches|
     // to avoid calling stl intersection (which requires a copy).
-    NodeSet* prefix_matches = first_term ? matches : &tmp_prefix_matches;
+    TitledUrlNodeSet* prefix_matches =
+        first_term ? matches : &tmp_prefix_matches;
     while (i != index_.end() &&
            i->first.size() >= term.size() &&
            term.compare(0, term.size(), i->first, 0, term.size()) == 0) {
 #if !defined(OS_ANDROID)
       prefix_matches->insert(i->second.begin(), i->second.end());
 #else
       // Work around a bug in the implementation of std::set::insert in the STL
       // used on android (http://crbug.com/367050).
-      for (NodeSet::const_iterator n = i->second.begin(); n != i->second.end();
+      for (TitledUrlNodeSet::const_iterator n = i->second.begin();
+           n != i->second.end();
            ++n)
         prefix_matches->insert(prefix_matches->end(), *n);
 #endif
       ++i;
     }
-    if (!first_term)
-      *matches = base::STLSetIntersection<NodeSet>(*prefix_matches, *matches);
+    if (!first_term) {
+      *matches =
+          base::STLSetIntersection<TitledUrlNodeSet>(*prefix_matches, *matches);
+    }
   }
   return !matches->empty();
 }
 
 std::vector<base::string16> BookmarkIndex::ExtractQueryWords(
     const base::string16& query) {
   std::vector<base::string16> terms;
   if (query.empty())
     return std::vector<base::string16>();
   query_parser::QueryParser parser;
   parser.ParseQueryWords(base::i18n::ToLower(query),
                          query_parser::MatchingAlgorithm::DEFAULT,
                          &terms);
   return terms;
 }
 
 void BookmarkIndex::RegisterNode(const base::string16& term,
-                                 const BookmarkNode* node) {
+                                 const TitledUrlNode* node) {
   index_[term].insert(node);
 }
 
 void BookmarkIndex::UnregisterNode(const base::string16& term,
-                                   const BookmarkNode* node) {
+                                   const TitledUrlNode* node) {
   Index::iterator i = index_.find(term);
   if (i == index_.end()) {
     // We can get here if the node has the same term more than once. For
-    // example, a bookmark with the title 'foo foo' would end up here.
+    // example, a node with the title 'foo foo' would end up here.
     return;
   }
   i->second.erase(node);
   if (i->second.empty())
     index_.erase(i);
 }
 
 }  // namespace bookmarks