electron/shell/browser/zoom_level_delegate.cc
2019-06-19 17:33:28 -07:00

168 lines
6.5 KiB
C++

// 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 "atom/browser/zoom_level_delegate.h"
#include <functional>
#include <memory>
#include <vector>
#include "base/bind.h"
#include "base/strings/string_number_conversions.h"
#include "base/values.h"
#include "components/prefs/json_pref_store.h"
#include "components/prefs/pref_filter.h"
#include "components/prefs/pref_registry_simple.h"
#include "components/prefs/pref_service_factory.h"
#include "components/prefs/scoped_user_pref_update.h"
#include "content/public/browser/browser_thread.h"
#include "content/public/common/page_zoom.h"
namespace atom {
namespace {
// Double that indicates the default zoom level.
const char kPartitionDefaultZoomLevel[] = "partition.default_zoom_level";
// Dictionary that maps hostnames to zoom levels. Hosts not in this pref will
// be displayed at the default zoom level.
const char kPartitionPerHostZoomLevels[] = "partition.per_host_zoom_levels";
std::string GetHash(const base::FilePath& partition_path) {
size_t int_key = std::hash<base::FilePath>()(partition_path);
return base::NumberToString(int_key);
}
} // namespace
// static
void ZoomLevelDelegate::RegisterPrefs(PrefRegistrySimple* registry) {
registry->RegisterDictionaryPref(kPartitionDefaultZoomLevel);
registry->RegisterDictionaryPref(kPartitionPerHostZoomLevels);
}
ZoomLevelDelegate::ZoomLevelDelegate(PrefService* pref_service,
const base::FilePath& partition_path)
: pref_service_(pref_service), host_zoom_map_(nullptr) {
DCHECK(pref_service_);
partition_key_ = GetHash(partition_path);
}
ZoomLevelDelegate::~ZoomLevelDelegate() {}
void ZoomLevelDelegate::SetDefaultZoomLevelPref(double level) {
if (content::ZoomValuesEqual(level, host_zoom_map_->GetDefaultZoomLevel()))
return;
DictionaryPrefUpdate update(pref_service_, kPartitionDefaultZoomLevel);
update->SetDouble(partition_key_, level);
host_zoom_map_->SetDefaultZoomLevel(level);
}
double ZoomLevelDelegate::GetDefaultZoomLevelPref() const {
double default_zoom_level = 0.0;
const base::DictionaryValue* default_zoom_level_dictionary =
pref_service_->GetDictionary(kPartitionDefaultZoomLevel);
// If no default has been previously set, the default returned is the
// value used to initialize default_zoom_level in this function.
default_zoom_level_dictionary->GetDouble(partition_key_, &default_zoom_level);
return default_zoom_level;
}
void ZoomLevelDelegate::OnZoomLevelChanged(
const content::HostZoomMap::ZoomLevelChange& change) {
if (change.mode != content::HostZoomMap::ZOOM_CHANGED_FOR_HOST)
return;
double level = change.zoom_level;
DictionaryPrefUpdate update(pref_service_, kPartitionPerHostZoomLevels);
base::DictionaryValue* host_zoom_dictionaries = update.Get();
DCHECK(host_zoom_dictionaries);
bool modification_is_removal =
content::ZoomValuesEqual(level, host_zoom_map_->GetDefaultZoomLevel());
base::DictionaryValue* host_zoom_dictionary = nullptr;
if (!host_zoom_dictionaries->GetDictionary(partition_key_,
&host_zoom_dictionary)) {
host_zoom_dictionary = host_zoom_dictionaries->SetDictionary(
partition_key_, std::make_unique<base::DictionaryValue>());
}
if (modification_is_removal)
host_zoom_dictionary->RemoveWithoutPathExpansion(change.host, nullptr);
else
host_zoom_dictionary->SetKey(change.host, base::Value(level));
}
void ZoomLevelDelegate::ExtractPerHostZoomLevels(
const base::DictionaryValue* host_zoom_dictionary) {
std::vector<std::string> keys_to_remove;
std::unique_ptr<base::DictionaryValue> host_zoom_dictionary_copy =
host_zoom_dictionary->DeepCopyWithoutEmptyChildren();
for (base::DictionaryValue::Iterator i(*host_zoom_dictionary_copy);
!i.IsAtEnd(); i.Advance()) {
const std::string& host(i.key());
double zoom_level = 0;
bool has_valid_zoom_level = i.value().GetAsDouble(&zoom_level);
// Filter out A) the empty host, B) zoom levels equal to the default; and
// remember them, so that we can later erase them from Prefs.
// Values of type B could further have been stored before the default zoom
// level was set to its current value. In either case, SetZoomLevelForHost
// will ignore type B values, thus, to have consistency with HostZoomMap's
// internal state, these values must also be removed from Prefs.
if (host.empty() || !has_valid_zoom_level ||
content::ZoomValuesEqual(zoom_level,
host_zoom_map_->GetDefaultZoomLevel())) {
keys_to_remove.push_back(host);
continue;
}
host_zoom_map_->SetZoomLevelForHost(host, zoom_level);
}
// Sanitize prefs to remove entries that match the default zoom level and/or
// have an empty host.
{
DictionaryPrefUpdate update(pref_service_, kPartitionPerHostZoomLevels);
base::DictionaryValue* host_zoom_dictionaries = update.Get();
base::DictionaryValue* sanitized_host_zoom_dictionary = nullptr;
host_zoom_dictionaries->GetDictionary(partition_key_,
&sanitized_host_zoom_dictionary);
for (const std::string& s : keys_to_remove)
sanitized_host_zoom_dictionary->RemoveWithoutPathExpansion(s, nullptr);
}
}
void ZoomLevelDelegate::InitHostZoomMap(content::HostZoomMap* host_zoom_map) {
// This init function must be called only once.
DCHECK(!host_zoom_map_);
DCHECK(host_zoom_map);
host_zoom_map_ = host_zoom_map;
// Initialize the default zoom level.
host_zoom_map_->SetDefaultZoomLevel(GetDefaultZoomLevelPref());
// Initialize the HostZoomMap with per-host zoom levels from the persisted
// zoom-level preference values.
const base::DictionaryValue* host_zoom_dictionaries =
pref_service_->GetDictionary(kPartitionPerHostZoomLevels);
const base::DictionaryValue* host_zoom_dictionary = nullptr;
if (host_zoom_dictionaries->GetDictionary(partition_key_,
&host_zoom_dictionary)) {
// Since we're calling this before setting up zoom_subscription_ below we
// don't need to worry that host_zoom_dictionary is indirectly affected
// by calls to HostZoomMap::SetZoomLevelForHost().
ExtractPerHostZoomLevels(host_zoom_dictionary);
}
zoom_subscription_ =
host_zoom_map_->AddZoomLevelChangedCallback(base::BindRepeating(
&ZoomLevelDelegate::OnZoomLevelChanged, base::Unretained(this)));
}
} // namespace atom