blob: fa9ed7647ebf04c0051a9a18384d8ab559553aa6 [file] [log] [blame]
// 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/titled_url_index.h"
#include <stdint.h>
#include "base/i18n/case_conversion.h"
#include "base/i18n/unicodestring.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_utils.h"
#include "components/bookmarks/browser/titled_url_match.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 {
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::i18n::UnicodeStringToString16(unicode_normalized_text);
}
} // namespace
TitledUrlIndex::TitledUrlIndex(std::unique_ptr<TitledUrlNodeSorter> sorter)
: sorter_(std::move(sorter)) {
}
TitledUrlIndex::~TitledUrlIndex() {
}
void TitledUrlIndex::Add(const TitledUrlNode* node) {
std::vector<base::string16> terms =
ExtractQueryWords(Normalize(node->GetTitledUrlNodeTitle()));
for (size_t i = 0; i < terms.size(); ++i)
RegisterNode(terms[i], node);
terms = ExtractQueryWords(
CleanUpUrlForMatching(node->GetTitledUrlNodeUrl(), nullptr));
for (size_t i = 0; i < terms.size(); ++i)
RegisterNode(terms[i], node);
}
void TitledUrlIndex::Remove(const TitledUrlNode* node) {
std::vector<base::string16> terms =
ExtractQueryWords(Normalize(node->GetTitledUrlNodeTitle()));
for (size_t i = 0; i < terms.size(); ++i)
UnregisterNode(terms[i], node);
terms = ExtractQueryWords(
CleanUpUrlForMatching(node->GetTitledUrlNodeUrl(), nullptr));
for (size_t i = 0; i < terms.size(); ++i)
UnregisterNode(terms[i], node);
}
void TitledUrlIndex::GetResultsMatching(
const base::string16& input_query,
size_t max_count,
query_parser::MatchingAlgorithm matching_algorithm,
std::vector<TitledUrlMatch>* results) {
const base::string16 query = Normalize(input_query);
std::vector<base::string16> terms = ExtractQueryWords(query);
if (terms.empty())
return;
TitledUrlNodeSet matches;
for (size_t i = 0; i < terms.size(); ++i) {
if (!GetResultsMatchingTerm(terms[i], i == 0, matching_algorithm,
&matches)) {
return;
}
}
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 (TitledUrlNodes::const_iterator i = sorted_nodes.begin();
i != sorted_nodes.end() && results->size() < max_count;
++i)
AddMatchToResults(*i, &parser, query_nodes, results);
}
void TitledUrlIndex::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 TitledUrlIndex::AddMatchToResults(
const TitledUrlNode* node,
query_parser::QueryParser* parser,
const query_parser::QueryNodeVector& query_nodes,
std::vector<TitledUrlMatch>* results) {
if (!node) {
return;
}
// 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 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->GetTitledUrlNodeTitle()));
parser->ExtractQueryWords(lower_title, &title_words);
base::OffsetAdjuster::Adjustments adjustments;
parser->ExtractQueryWords(
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);
}
TitledUrlMatch match;
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 =
TitledUrlMatch::OffsetsFromMatchPositions(url_matches);
base::OffsetAdjuster::UnadjustOffsets(adjustments, &offsets);
url_matches =
TitledUrlMatch::ReplaceOffsetsInMatchPositions(url_matches, offsets);
match.url_match_positions.swap(url_matches);
match.node = node;
results->push_back(match);
}
bool TitledUrlIndex::GetResultsMatchingTerm(
const base::string16& term,
bool first_term,
query_parser::MatchingAlgorithm matching_algorithm,
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 title/URL pairs with this term.
if (first_term) {
(*matches) = i->second;
return true;
}
*matches = base::STLSetIntersection<TitledUrlNodeSet>(i->second, *matches);
} else {
// Loop through index adding all entries that start with term to
// |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).
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 (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<TitledUrlNodeSet>(*prefix_matches, *matches);
}
}
return !matches->empty();
}
std::vector<base::string16> TitledUrlIndex::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 TitledUrlIndex::RegisterNode(const base::string16& term,
const TitledUrlNode* node) {
index_[term].insert(node);
}
void TitledUrlIndex::UnregisterNode(const base::string16& term,
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 node with the title 'foo foo' would end up here.
return;
}
i->second.erase(node);
if (i->second.empty())
index_.erase(i);
}
} // namespace bookmarks