Refactored code for timezone settings.

chrome/browser/ui/webui/options2/chromeos/timezone_options_util.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/ui/webui/options2/chromeos/timezone_options_util.h"
+
+#include <string>
+
+#include "base/i18n/rtl.h"
+#include "base/lazy_instance.h"
+#include "base/string_util.h"
+#include "base/stringprintf.h"
+#include "base/synchronization/lock.h"
+#include "base/utf_string_conversions.h"
+#include "base/values.h"
+#include "chrome/browser/chromeos/system/timezone_settings.h"
+#include "grit/generated_resources.h"
+#include "ui/base/l10n/l10n_util.h"
+#include "unicode/calendar.h"
+#include "unicode/timezone.h"
+#include "unicode/ures.h"
+#include "unicode/utypes.h"
+
+namespace {
+
+struct UResClose {
+  inline void operator() (UResourceBundle* b) const {
+    ures_close(b);
+  }
+};
+
+static base::LazyInstance<base::Lock>::Leaky
+    g_timezone_bundle_lock = LAZY_INSTANCE_INITIALIZER;
+
+// Returns an exemplary city in the given timezone.
+string16 GetExemplarCity(const icu::TimeZone& zone) {
+  // TODO(jungshik): After upgrading to ICU 4.6, use U_ICUDATA_ZONE
+  static const char* zone_bundle_name = NULL;
+
+  // These will be leaked at the end.
+  static UResourceBundle *zone_bundle = NULL;
+  static UResourceBundle *zone_strings = NULL;
+
+  UErrorCode status = U_ZERO_ERROR;
+  {
+    base::AutoLock lock(g_timezone_bundle_lock.Get());
+    if (zone_bundle == NULL)
+      zone_bundle = ures_open(zone_bundle_name, uloc_getDefault(), &status);
+
+    if (zone_strings == NULL)
+      zone_strings = ures_getByKey(zone_bundle, "zone_strings", NULL, &status);
+  }
+
+  icu::UnicodeString zone_id;
+  zone.getID(zone_id);
+  std::string zone_id_str;
+  zone_id.toUTF8String(zone_id_str);
+
+  // Resource keys for timezones use ':' in place of '/'.
+  ReplaceSubstringsAfterOffset(&zone_id_str, 0, "/", ":");
+  scoped_ptr_malloc<UResourceBundle, UResClose> zone_item(
+      ures_getByKey(zone_strings, zone_id_str.c_str(), NULL, &status));
+  icu::UnicodeString city;
+  if (!U_FAILURE(status)) {
+    city = icu::ures_getUnicodeStringByKey(zone_item.get(), "ec", &status);
+    if (U_SUCCESS(status))
+      return string16(city.getBuffer(), city.length());
+  }
+
+  // Fallback case in case of failure.
+  ReplaceSubstringsAfterOffset(&zone_id_str, 0, ":", "/");
+  // Take the last component of a timezone id (e.g. 'Baz' in 'Foo/Bar/Baz').
+  // Depending on timezones, keeping all but the 1st component
+  // (e.g. Bar/Baz) may be better, but our current list does not have
+  // any timezone for which that's the case.
+  std::string::size_type slash_pos = zone_id_str.rfind('/');
+  if (slash_pos != std::string::npos && slash_pos < zone_id_str.size())
+    zone_id_str.erase(0, slash_pos + 1);
+  // zone id has '_' in place of ' '.
+  ReplaceSubstringsAfterOffset(&zone_id_str, 0, "_", " ");
+  return ASCIIToUTF16(zone_id_str);
+}
+
+// Gets the given timezone's name for visualization.
+string16 GetTimezoneName(const icu::TimeZone& timezone) {
+  // Instead of using the raw_offset, use the offset in effect now.
+  // For instance, US Pacific Time, the offset shown will be -7 in summer
+  // while it'll be -8 in winter.
+  int raw_offset, dst_offset;
+  UDate now = icu::Calendar::getNow();
+  UErrorCode status = U_ZERO_ERROR;
+  timezone.getOffset(now, false, raw_offset, dst_offset, status);
+  DCHECK(U_SUCCESS(status));
+  int offset = raw_offset + dst_offset;
+  // |offset| is in msec.
+  int minute_offset = std::abs(offset) / 60000;
+  int hour_offset = minute_offset / 60;
+  int min_remainder = minute_offset % 60;
+  // Some timezones have a non-integral hour offset. So, we need to use hh:mm
+  // form.
+  std::string  offset_str = base::StringPrintf(offset >= 0 ?
+      "UTC+%d:%02d" : "UTC-%d:%02d", hour_offset, min_remainder);
+
+  // TODO(jungshik): When coming up with a better list of timezones, we also
+  // have to come up with better 'display' names. One possibility is to list
+  // multiple cities (e.g. "Los Angeles, Vancouver .." in the order of
+  // the population of a country the city belongs to.).
+  // We can also think of using LONG_GENERIC or LOCATION once we upgrade
+  // to ICU 4.6.
+  // In the meantime, we use "LONG" name with "Exemplar City" to distinguish
+  // multiple timezones with the same "LONG" name but with different
+  // rules (e.g. US Mountain Time in Denver vs Phoenix).
+  icu::UnicodeString name;
+  timezone.getDisplayName(dst_offset != 0, icu::TimeZone::LONG, name);
+  string16 result(l10n_util::GetStringFUTF16(
+      IDS_OPTIONS_SETTINGS_TIMEZONE_DISPLAY_TEMPLATE, ASCIIToUTF16(offset_str),
+      string16(name.getBuffer(), name.length()), GetExemplarCity(timezone)));
+  base::i18n::AdjustStringForLocaleDirection(&result);
+  return result;
+}
+
+}  // namespace
+
+namespace options2 {
+
+// Creates a list of pairs of each timezone's ID and name.
+scoped_ptr<base::ListValue> GetTimezoneList() {
+  const std::vector<icu::TimeZone*> &timezones =
+      chromeos::system::TimezoneSettings::GetInstance()->GetTimezoneList();
+  scoped_ptr<base::ListValue> timezoneList(new base::ListValue());
+  for (std::vector<icu::TimeZone*>::const_iterator iter = timezones.begin();
+       iter != timezones.end(); ++iter) {
+    const icu::TimeZone* timezone = *iter;
+    base::ListValue* option = new base::ListValue();
+    option->Append(Value::CreateStringValue(
+        chromeos::system::TimezoneSettings::GetTimezoneID(*timezone)));
+    option->Append(Value::CreateStringValue(GetTimezoneName(*timezone)));
+    timezoneList->Append(option);
+  }
+  return timezoneList.Pass();
+}
+
+}  // namespace options2