Introduce BookmarkClient interface to abstract embedder

chrome/browser/bookmarks/bookmark_index.cc

 // Copyright (c) 2012 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 "chrome/browser/bookmarks/bookmark_index.h"
 
 #include <algorithm>
+#include <functional>
 #include <iterator>
 #include <list>
 
 #include "base/i18n/case_conversion.h"
 #include "base/strings/string16.h"
-#include "chrome/browser/bookmarks/bookmark_model.h"
-#include "chrome/browser/history/history_service.h"
-#include "chrome/browser/history/history_service_factory.h"
-#include "chrome/browser/history/url_database.h"
+#include "components/bookmarks/core/browser/bookmark_client.h"
+#include "components/bookmarks/core/browser/bookmark_node.h"
 #include "components/bookmarks/core/browser/bookmark_title_match.h"
 #include "components/query_parser/query_parser.h"
 #include "third_party/icu/source/common/unicode/normalizer2.h"
 
 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(NULL, "nfkc", UNORM2_COMPOSE, status);
   icu::UnicodeString unicode_text(text.data(), text.length());
   icu::UnicodeString unicode_normalized_text;
   normalizer2->normalize(unicode_text, unicode_normalized_text, status);
   if (U_FAILURE(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
+    : std::binary_function<BookmarkClient::NodeTypedCountPair,
+                           BookmarkClient::NodeTypedCountPair,
+                           bool> {
+  bool operator()(const BookmarkClient::NodeTypedCountPair& a,
+                  const BookmarkClient::NodeTypedCountPair& b) const {
+    return a.second > b.second;
+  }
+};
+
+// Extract the const Node* stored in a NodeTypedCountPair.
+struct NodeFromNodeTypedCountPairFunctor
+    : std::unary_function<BookmarkClient::NodeTypedCountPair,
+                          const BookmarkNode*> {
+  const BookmarkNode* operator()(
+      const BookmarkClient::NodeTypedCountPair& pair) const {
+    return pair.first;
+  }
+};
+
 }  // namespace
 
 // Used when finding the set of bookmarks that match a query. Each match
 // represents a set of terms (as an interator into the Index) matching the
 // query as well as the set of nodes that contain those terms in their titles.
 struct BookmarkIndex::Match {
   // List of terms matching the query.
   std::list<Index::const_iterator> terms;
 
   // The set of nodes matching the terms. As an optimization this is empty
@@ skipping 16 matching lines @@
 
 BookmarkIndex::NodeSet::const_iterator
     BookmarkIndex::Match::nodes_begin() const {
   return nodes.empty() ? terms.front()->second.begin() : nodes.begin();
 }
 
 BookmarkIndex::NodeSet::const_iterator BookmarkIndex::Match::nodes_end() const {
   return nodes.empty() ? terms.front()->second.end() : nodes.end();
 }
 
-BookmarkIndex::BookmarkIndex(content::BrowserContext* browser_context)
-    : browser_context_(browser_context) {
+BookmarkIndex::BookmarkIndex(BookmarkClient* client) : client_(client) {
 }
 
 BookmarkIndex::~BookmarkIndex() {
 }
 
 void BookmarkIndex::Add(const BookmarkNode* node) {
   if (!node->is_url())
     return;
   std::vector<base::string16> terms =
       ExtractQueryWords(Normalize(node->GetTitle()));
@@ skipping 19 matching lines @@
   std::vector<base::string16> terms = ExtractQueryWords(query);
   if (terms.empty())
     return;
 
   Matches matches;
   for (size_t i = 0; i < terms.size(); ++i) {
     if (!GetBookmarksWithTitleMatchingTerm(terms[i], i == 0, &matches))
       return;
   }
 
-  NodeTypedCountPairs node_typed_counts;
-  SortMatches(matches, &node_typed_counts);
+  Nodes 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;
   ScopedVector<query_parser::QueryNode> query_nodes;
   parser.ParseQueryNodes(query, &query_nodes.get());
 
   // 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 (NodeTypedCountPairs::const_iterator i = node_typed_counts.begin();
-       i != node_typed_counts.end() && results->size() < max_count; ++i)
-    AddMatchToResults(i->first, &parser, query_nodes.get(), results);
+  for (Nodes::const_iterator i = sorted_nodes.begin();
+       i != sorted_nodes.end() && results->size() < max_count;
+       ++i)
+    AddMatchToResults(*i, &parser, query_nodes.get(), results);
 }
 
 void BookmarkIndex::SortMatches(const Matches& matches,
-                                NodeTypedCountPairs* node_typed_counts) const {
-  HistoryService* const history_service = browser_context_ ?
-      HistoryServiceFactory::GetForProfile(
-          Profile::FromBrowserContext(browser_context_),
-          Profile::EXPLICIT_ACCESS) : NULL;
-
-  history::URLDatabase* url_db = history_service ?
-      history_service->InMemoryDatabase() : NULL;
-
-  for (Matches::const_iterator i = matches.begin(); i != matches.end(); ++i)
-    ExtractBookmarkNodePairs(url_db, *i, node_typed_counts);
-
-  std::sort(node_typed_counts->begin(), node_typed_counts->end(),
-            &NodeTypedCountPairSortFunc);
-  // Eliminate duplicates.
-  node_typed_counts->erase(std::unique(node_typed_counts->begin(),
-                                       node_typed_counts->end()),
-                           node_typed_counts->end());
-}
-
-void BookmarkIndex::ExtractBookmarkNodePairs(
-    history::URLDatabase* url_db,
-    const Match& match,
-    NodeTypedCountPairs* node_typed_counts) const {
-
-  for (NodeSet::const_iterator i = match.nodes_begin();
-       i != match.nodes_end(); ++i) {
-    int typed_count = 0;
-
-    // If |url_db| is the InMemoryDatabase, it might not cache all URLRows, but
-    // it guarantees to contain those with |typed_count| > 0. Thus, if we cannot
-    // fetch the URLRow, it is safe to assume that its |typed_count| is 0.
-    history::URLRow url;
-    if (url_db && url_db->GetRowForURL((*i)->url(), &url))
-      typed_count = url.typed_count();
-
-    NodeTypedCountPair pair(*i, typed_count);
-    node_typed_counts->push_back(pair);
+                                Nodes* sorted_nodes) const {
+  NodeSet nodes;
+  for (Matches::const_iterator i = matches.begin(); i != matches.end(); ++i) {
+    nodes.insert(i->nodes_begin(), i->nodes_end());
+  }
+  if (client_->SupportsTypedCountForNodes()) {
+    BookmarkClient::NodeTypedCountPairs node_typed_counts;
+    client_->GetTypedCountForNodes(nodes, &node_typed_counts);
+    std::sort(node_typed_counts.begin(),
+              node_typed_counts.end(),
+              NodeTypedCountPairSortFunctor());
+    sorted_nodes->reserve(sorted_nodes->size() + node_typed_counts.size());
+    std::transform(node_typed_counts.begin(),
+                   node_typed_counts.end(),
+                   std::back_inserter(*sorted_nodes),
+                   NodeFromNodeTypedCountPairFunctor());
+  } else {
+    sorted_nodes->insert(sorted_nodes->end(), nodes.begin(), nodes.end());
   }
 }
 
 void BookmarkIndex::AddMatchToResults(
     const BookmarkNode* node,
     query_parser::QueryParser* parser,
     const std::vector<query_parser::QueryNode*>& query_nodes,
     std::vector<BookmarkTitleMatch>* results) {
   BookmarkTitleMatch title_match;
   // Check that the result matches the query.  The previous search
@@ skipping 110 matching lines @@
   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.
     return;
   }
   i->second.erase(node);
   if (i->second.empty())
     index_.erase(i);
 }