// Copyright (c) 2006-2008 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.
//
// This file defines the methods useful for uninstalling Chrome.

#include "chrome/installer/setup/uninstall.h"

#include <atlbase.h>
#include <windows.h>
#include <msi.h>

#include "base/file_util.h"
#include "base/path_service.h"
#include "base/registry.h"
#include "base/scoped_ptr.h"
#include "base/string_util.h"
#include "base/win_util.h"
#include "base/wmi_util.h"
#include "chrome/app/result_codes.h"
#include "chrome/common/chrome_constants.h"
#include "chrome/installer/setup/setup.h"
#include "chrome/installer/setup/setup_constants.h"
#include "chrome/installer/util/browser_distribution.h"
#include "chrome/installer/util/helper.h"
#include "chrome/installer/util/install_util.h"
#include "chrome/installer/util/l10n_string_util.h"
#include "chrome/installer/util/logging_installer.h"
#include "chrome/installer/util/google_update_constants.h"
#include "chrome/installer/util/google_update_settings.h"
#include "chrome/installer/util/shell_util.h"
#include "chrome/installer/util/util_constants.h"
#include "chrome/installer/util/version.h"

#include "installer_util_strings.h"

namespace {

// This method deletes Chrome shortcut folder from Windows Start menu. It
// checks system_uninstall to see if the shortcut is in all users start menu
// or current user start menu.
void DeleteChromeShortcut(bool system_uninstall) {
  std::wstring shortcut_path;
  if (system_uninstall) {
    PathService::Get(base::DIR_COMMON_START_MENU, &shortcut_path);
  } else {
    PathService::Get(base::DIR_START_MENU, &shortcut_path);
  }
  if (shortcut_path.empty()) {
    LOG(ERROR) << "Failed to get location for shortcut.";
  } else {
    BrowserDistribution* dist = BrowserDistribution::GetDistribution();
    file_util::AppendToPath(&shortcut_path, dist->GetApplicationName());
    LOG(INFO) << "Deleting shortcut " << shortcut_path;
    if (!file_util::Delete(shortcut_path, true))
      LOG(ERROR) << "Failed to delete folder: " << shortcut_path;
  }
}

// This method tries to delete a registry key and logs an error message
// in case of failure. It returns true if deletion is successful,
// otherwise false.
bool DeleteRegistryKey(RegKey& key, const std::wstring& key_path) {
  LOG(INFO) << "Deleting registry key " << key_path;
  if (!key.DeleteKey(key_path.c_str())) {
    LOG(ERROR) << "Failed to delete registry key: " << key_path;
    return false;
  }
  return true;
}

// This method tries to delete a registry value and logs an error message
// in case of failure. It returns true if deletion is successful,
// otherwise false.
bool DeleteRegistryValue(HKEY reg_root, const std::wstring& key_path,
                         const std::wstring& value_name) {
  RegKey key(reg_root, key_path.c_str(), KEY_ALL_ACCESS);
  LOG(INFO) << "Deleting registry value " << value_name;
  if (!key.DeleteValue(value_name.c_str())) {
    LOG(ERROR) << "Failed to delete registry value: " << value_name;
    return false;
  }
  return true;
}

// This method checks if Chrome is currently running or if the user has
// cancelled the uninstall operation by clicking Cancel on the confirmation
// box that Chrome pops up.
installer_util::InstallStatus IsChromeActiveOrUserCancelled(
    bool system_uninstall) {
  static const std::wstring kCmdLineOptions(L" --uninstall");
  static const int32 kTimeOutMs = 30000;
  int32 exit_code = ResultCodes::NORMAL_EXIT;
  bool is_timeout = false;

  // We want to continue with the uninstallation only when chrome.exe either
  // returns NORMAL_EXIT (means Chrome is not running, user has confirmed
  // uninstallation and sentinel file/desktop/ql shortcuts have been
  // cleaned up) or UNINSTALL_DELETE_FILE_ERROR (means Chrome is not running,
  // user has confirmed uninstallation but there was a problem with deleting
  // sentinel file, desktop or ql shortcuts).
  LOG(INFO) << "Launching Chrome to do uninstall tasks.";
  if (installer::LaunchChromeAndWaitForResult(system_uninstall,
                                              kCmdLineOptions,
                                              kTimeOutMs,
                                              &exit_code,
                                              &is_timeout)) {
    if (is_timeout || exit_code == ResultCodes::UNINSTALL_CHROME_ALIVE) {
      LOG(INFO) << "Can't uninstall when chrome is still running";
      return installer_util::CHROME_RUNNING;
    } else if (exit_code == ResultCodes::UNINSTALL_USER_CANCEL) {
      LOG(INFO) << "User cancelled uninstall operation";
      return installer_util::UNINSTALL_CANCELLED;
    } else if (exit_code == ResultCodes::NORMAL_EXIT) {
      LOG(INFO) << "chrome.exe confirmed uninstallation from user.";
      return installer_util::UNINSTALL_CONFIRMED;
    } else if (exit_code == ResultCodes::UNINSTALL_DELETE_FILE_ERROR) {
      LOG(ERROR) << "chrome.exe returned delete file error.";
      return installer_util::UNINSTALL_CONFIRMED;
    }
  }

  return installer_util::UNINSTALL_FAILED;
}
}  // namespace


installer_util::InstallStatus installer_setup::UninstallChrome(
    const std::wstring& exe_path, bool system_uninstall,
    const installer::Version& installed_version, bool remove_all) {
  installer_util::InstallStatus status =
      IsChromeActiveOrUserCancelled(system_uninstall);
  if (status != installer_util::UNINSTALL_CONFIRMED)
    return status;

  BrowserDistribution* dist = BrowserDistribution::GetDistribution();
  dist->DoPreUninstallOperations();
#if defined(GOOGLE_CHROME_BUILD)
  // TODO(rahulk): This should be done by DoPreUninstallOperations call above
  wchar_t product[39];  // GUID + '\0'
  MsiSetInternalUI(INSTALLUILEVEL_NONE, NULL);  // Don't show any UI to user.
  for (int i = 0; MsiEnumRelatedProducts(google_update::kGearsUpgradeCode, 0, i,
                                         product) != ERROR_NO_MORE_ITEMS; ++i) {
    LOG(INFO) << "Uninstalling Gears - " << product;
    unsigned int ret = MsiConfigureProduct(product, INSTALLLEVEL_MAXIMUM,
                                           INSTALLSTATE_ABSENT);
    if (ret != ERROR_SUCCESS)
      LOG(ERROR) << "Failed to uninstall Gears " << product << ": " << ret;
  }
#endif

  // Chrome is not in use so lets uninstall Chrome by deleting various files
  // and registry entries. Here we will just make best effort and keep going
  // in case of errors.
  // First delete shortcut from Start->Programs.
  DeleteChromeShortcut(system_uninstall);

  // Delete the registry keys (Uninstall key and Version key).
  HKEY reg_root = system_uninstall ? HKEY_LOCAL_MACHINE : HKEY_CURRENT_USER;
  RegKey key(reg_root, L"", KEY_ALL_ACCESS);
  DeleteRegistryKey(key, dist->GetUninstallRegPath());
  DeleteRegistryKey(key, dist->GetVersionKey());

  // Delete Software\Classes\ChromeHTML,
  // Software\Clients\StartMenuInternet\chrome.exe and
  // Software\RegisteredApplications\Chrome
  std::wstring html_prog_id(ShellUtil::kRegClasses);
  file_util::AppendToPath(&html_prog_id, ShellUtil::kChromeHTMLProgId);
  DeleteRegistryKey(key, html_prog_id);

  std::wstring set_access_key(ShellUtil::kRegStartMenuInternet);
  file_util::AppendToPath(&set_access_key, installer_util::kChromeExe);
  DeleteRegistryKey(key, set_access_key);

  DeleteRegistryValue(reg_root, ShellUtil::kRegRegisteredApplications,
                      dist->GetApplicationName());
  key.Close();

  // Delete shared registry keys as well (these require admin rights) if
  // remove_all option is specified.
  if (remove_all) {
    RegKey hklm_key(HKEY_LOCAL_MACHINE, L"", KEY_ALL_ACCESS);
    DeleteRegistryKey(hklm_key, set_access_key);
    DeleteRegistryKey(hklm_key, html_prog_id);
    DeleteRegistryValue(HKEY_LOCAL_MACHINE,
                        ShellUtil::kRegRegisteredApplications,
                        dist->GetApplicationName());

    // Delete media player registry key that exists only in HKLM.
    std::wstring reg_path(installer::kMediaPlayerRegPath);
    file_util::AppendToPath(&reg_path, installer_util::kChromeExe);
    DeleteRegistryKey(hklm_key, reg_path);
    hklm_key.Close();
  }

  // Finally delete all the files from Chrome folder after moving setup.exe
  // to a temp location.
  std::wstring install_path(installer::GetChromeInstallPath(system_uninstall));
  if (install_path.empty()) {
    LOG(ERROR) << "Could not get installation destination path.";
    // Nothing else we could do for uninstall, so we return.
    return installer_util::UNINSTALL_FAILED;
  } else {
    LOG(INFO) << "install destination path: " << install_path;
  }

  std::wstring setup_exe(installer::GetInstallerPathUnderChrome(
      install_path, installed_version.GetString()));
  file_util::AppendToPath(&setup_exe, file_util::GetFilenameFromPath(exe_path));

  std::wstring temp_file;
  file_util::CreateTemporaryFileName(&temp_file);
  file_util::Move(setup_exe, temp_file);

  LOG(INFO) << "Deleting install path " << install_path;
  if (!file_util::Delete(install_path, true))
    LOG(ERROR) << "Failed to delete folder: " << install_path;

  LOG(INFO) << "Uninstallation complete. Launching Uninstall survey.";
  dist->DoPostUninstallOperations(installed_version);
  return installer_util::UNINSTALL_SUCCESSFUL;
}