app/l10n_util_win.cc

// Copyright (c) 2009 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 "app/l10n_util.h"

#include <algorithm>
#include <windowsx.h>

#include "app/l10n_util_win.h"
#include "base/i18n/rtl.h"
#include "base/string_util.h"
#include "base/win_util.h"

#include "grit/app_locale_settings.h"

namespace {

void AdjustLogFont(const std::wstring& font_family,
                   double font_size_scaler,
                   LOGFONT* logfont) {
  DCHECK(font_size_scaler > 0);
  font_size_scaler = std::max(std::min(font_size_scaler, 2.0), 0.7);
  logfont->lfHeight = static_cast<long>(font_size_scaler *
      static_cast<double>(abs(logfont->lfHeight)) + 0.5) *
      (logfont->lfHeight > 0 ? 1 : -1);

  // TODO(jungshik): We may want to check the existence of the font.
  // If it's not installed, we shouldn't adjust the font.
  if (font_family != L"default") {
    int name_len = std::min(static_cast<int>(font_family.size()),
                            LF_FACESIZE -1);
    memcpy(logfont->lfFaceName, font_family.data(), name_len * sizeof(WORD));
    logfont->lfFaceName[name_len] = 0;
  }
}

}  // namespace

namespace l10n_util {

int GetExtendedStyles() {
  return !base::i18n::IsRTL() ? 0 : WS_EX_LAYOUTRTL | WS_EX_RTLREADING;
}

int GetExtendedTooltipStyles() {
  return !base::i18n::IsRTL() ? 0 : WS_EX_LAYOUTRTL;
}

void HWNDSetRTLLayout(HWND hwnd) {
  DWORD ex_style = ::GetWindowLong(hwnd, GWL_EXSTYLE);

  // We don't have to do anything if the style is already set for the HWND.
  if (!(ex_style & WS_EX_LAYOUTRTL)) {
    ex_style |= WS_EX_LAYOUTRTL;
    ::SetWindowLong(hwnd, GWL_EXSTYLE, ex_style);

    // Right-to-left layout changes are not applied to the window immediately
    // so we should make sure a WM_PAINT is sent to the window by invalidating
    // the entire window rect.
    ::InvalidateRect(hwnd, NULL, true);
  }
}

bool IsLocaleSupportedByOS(const std::string& locale) {
  // Block Amharic on Windows XP.
  return win_util::GetWinVersion() >= win_util::WINVERSION_VISTA ||
      !LowerCaseEqualsASCII(locale, "am");
}

bool NeedOverrideDefaultUIFont(std::wstring* override_font_family,
                               double* font_size_scaler) {
  // This is rather simple-minded to deal with the UI font size
  // issue for some Indian locales (ml, bn, hi) for which
  // the default Windows fonts are too small to be legible.  For those
  // locales, IDS_UI_FONT_FAMILY is set to an actual font family to
  // use while for other locales, it's set to 'default'.

  // XP and Vista or later have different font size issues and
  // we need separate ui font specifications.
  int ui_font_family_id = IDS_UI_FONT_FAMILY;
  int ui_font_size_scaler_id = IDS_UI_FONT_SIZE_SCALER;
  if (win_util::GetWinVersion() < win_util::WINVERSION_VISTA) {
    ui_font_family_id = IDS_UI_FONT_FAMILY_XP;
    ui_font_size_scaler_id = IDS_UI_FONT_SIZE_SCALER_XP;
  }

  std::wstring ui_font_family = GetString(ui_font_family_id);
  int scaler100 = StringToInt(l10n_util::GetString(ui_font_size_scaler_id));
  // We use the OS default in two cases:
  // 1) The resource bundle has 'default' and '100' for font family and
  //    font scaler.
  // 2) The resource bundle is not available for some reason and
  //    ui_font_family is empty.
  if (ui_font_family == L"default" && scaler100 == 100 ||
      ui_font_family.empty())
    return false;
  if (override_font_family && font_size_scaler) {
    override_font_family->swap(ui_font_family);
    *font_size_scaler = scaler100 / 100.0;
  }
  return true;
}

void AdjustUIFont(LOGFONT* logfont) {
  std::wstring ui_font_family;
  double ui_font_size_scaler;
  if (NeedOverrideDefaultUIFont(&ui_font_family, &ui_font_size_scaler))
    AdjustLogFont(ui_font_family, ui_font_size_scaler, logfont);
}

void AdjustUIFontForWindow(HWND hwnd) {
  std::wstring ui_font_family;
  double ui_font_size_scaler;
  if (NeedOverrideDefaultUIFont(&ui_font_family, &ui_font_size_scaler)) {
    LOGFONT logfont;
    if (GetObject(GetWindowFont(hwnd), sizeof(logfont), &logfont)) {
      AdjustLogFont(ui_font_family, ui_font_size_scaler, &logfont);
      HFONT hfont = CreateFontIndirect(&logfont);
      if (hfont)
        SetWindowFont(hwnd, hfont, FALSE);
    }
  }
}

}  // namespace l10n_util