// 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 "chrome/browser/ui/ash/chrome_screenshot_grabber.h"

#include <stddef.h>

#include "ash/shell.h"
#include "ash/system/system_notifier.h"
#include "base/base64.h"
#include "base/bind.h"
#include "base/callback.h"
#include "base/files/file_util.h"
#include "base/i18n/time_formatting.h"
#include "base/macros.h"
#include "base/strings/stringprintf.h"
#include "base/strings/utf_string_conversions.h"
#include "build/build_config.h"
#include "chrome/browser/browser_process.h"
#include "chrome/browser/download/download_prefs.h"
#include "chrome/browser/notifications/notification_ui_manager.h"
#include "chrome/browser/platform_util.h"
#include "chrome/browser/profiles/profile.h"
#include "chrome/browser/profiles/profile_manager.h"
#include "chrome/common/pref_names.h"
#include "components/prefs/pref_service.h"
#include "content/public/browser/browser_thread.h"
#include "content/public/browser/user_metrics.h"
#include "grit/ash_strings.h"
#include "grit/theme_resources.h"
#include "ui/base/clipboard/clipboard.h"
#include "ui/base/clipboard/scoped_clipboard_writer.h"
#include "ui/base/l10n/l10n_util.h"
#include "ui/base/resource/resource_bundle.h"
#include "ui/strings/grit/ui_strings.h"

#if defined(OS_CHROMEOS)
#include "chrome/browser/chromeos/drive/file_system_util.h"
#include "chrome/browser/chromeos/file_manager/open_util.h"
#include "chrome/browser/notifications/notifier_state_tracker.h"
#include "chrome/browser/notifications/notifier_state_tracker_factory.h"
#include "chromeos/login/login_state.h"
#include "components/drive/file_system_interface.h"
#endif

namespace {

const char kNotificationId[] = "screenshot";

#if defined(OS_CHROMEOS)
const char kNotificationOriginUrl[] = "chrome://screenshot";
#endif

const char kImageClipboardFormatPrefix[] = "<img src='data:image/png;base64,";
const char kImageClipboardFormatSuffix[] = "'>";

void CopyScreenshotToClipboard(scoped_refptr<base::RefCountedString> png_data) {
  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);

  std::string encoded;
  base::Base64Encode(png_data->data(), &encoded);

  // Only cares about HTML because ChromeOS doesn't need other formats.
  // TODO(dcheng): Why don't we take advantage of the ability to write bitmaps
  // to the clipboard here?
  {
    ui::ScopedClipboardWriter scw(ui::CLIPBOARD_TYPE_COPY_PASTE);
    std::string html(kImageClipboardFormatPrefix);
    html += encoded;
    html += kImageClipboardFormatSuffix;
    scw.WriteHTML(base::UTF8ToUTF16(html), std::string());
  }
  content::RecordAction(base::UserMetricsAction("Screenshot_CopyClipboard"));
}

void ReadFileAndCopyToClipboardLocal(const base::FilePath& screenshot_path) {
  DCHECK(content::BrowserThread::GetBlockingPool()->RunsTasksOnCurrentThread());

  scoped_refptr<base::RefCountedString> png_data(new base::RefCountedString());
  if (!base::ReadFileToString(screenshot_path, &(png_data->data()))) {
    LOG(ERROR) << "Failed to read the screenshot file: "
               << screenshot_path.value();
    return;
  }

  content::BrowserThread::PostTask(
      content::BrowserThread::UI, FROM_HERE,
      base::Bind(CopyScreenshotToClipboard, png_data));
}

#if defined(OS_CHROMEOS)
void ReadFileAndCopyToClipboardDrive(drive::FileError error,
                                     const base::FilePath& file_path,
                                     scoped_ptr<drive::ResourceEntry> entry) {
  if (error != drive::FILE_ERROR_OK) {
    LOG(ERROR) << "Failed to read the screenshot path on drive: "
               << drive::FileErrorToString(error);
    return;
  }
  content::BrowserThread::GetBlockingPool()->PostTask(
      FROM_HERE, base::Bind(&ReadFileAndCopyToClipboardLocal, file_path));
}
#endif

// Delegate for a notification. This class has two roles: to implement callback
// methods for notification, and to provide an identity of the associated
// notification.
class ScreenshotGrabberNotificationDelegate : public NotificationDelegate {
 public:
  ScreenshotGrabberNotificationDelegate(bool success,
                                        Profile* profile,
                                        const base::FilePath& screenshot_path)
      : success_(success),
        profile_(profile),
        screenshot_path_(screenshot_path) {}

  // Overridden from NotificationDelegate:
  void Click() override {
    if (!success_)
      return;
    platform_util::ShowItemInFolder(profile_, screenshot_path_);
  }
  void ButtonClick(int button_index) override {
    DCHECK(success_ && button_index == 0);

// To avoid keeping the screenshot image on memory, it will re-read the
// screenshot file and copy it to the clipboard.
#if defined(OS_CHROMEOS)
    if (drive::util::IsUnderDriveMountPoint(screenshot_path_)) {
      drive::FileSystemInterface* file_system =
          drive::util::GetFileSystemByProfile(profile_);
      file_system->GetFile(drive::util::ExtractDrivePath(screenshot_path_),
                           base::Bind(&ReadFileAndCopyToClipboardDrive));
      return;
    }
#endif
    content::BrowserThread::GetBlockingPool()->PostTask(
        FROM_HERE,
        base::Bind(&ReadFileAndCopyToClipboardLocal, screenshot_path_));
  }
  bool HasClickedListener() override { return success_; }
  std::string id() const override { return std::string(kNotificationId); }

 private:
  ~ScreenshotGrabberNotificationDelegate() override {}

  const bool success_;
  Profile* profile_;
  const base::FilePath screenshot_path_;

  DISALLOW_COPY_AND_ASSIGN(ScreenshotGrabberNotificationDelegate);
};

#if defined(OS_CHROMEOS)
int GetScreenshotNotificationTitle(
    ui::ScreenshotGrabberObserver::Result screenshot_result) {
  switch (screenshot_result) {
    case ui::ScreenshotGrabberObserver::SCREENSHOTS_DISABLED:
      return IDS_ASH_SCREENSHOT_NOTIFICATION_TITLE_DISABLED;
    case ui::ScreenshotGrabberObserver::SCREENSHOT_SUCCESS:
      return IDS_ASH_SCREENSHOT_NOTIFICATION_TITLE_SUCCESS;
    default:
      return IDS_ASH_SCREENSHOT_NOTIFICATION_TITLE_FAIL;
  }
}

int GetScreenshotNotificationText(
    ui::ScreenshotGrabberObserver::Result screenshot_result) {
  switch (screenshot_result) {
    case ui::ScreenshotGrabberObserver::SCREENSHOTS_DISABLED:
      return IDS_ASH_SCREENSHOT_NOTIFICATION_TEXT_DISABLED;
    case ui::ScreenshotGrabberObserver::SCREENSHOT_SUCCESS:
      return IDS_ASH_SCREENSHOT_NOTIFICATION_TEXT_SUCCESS;
    default:
      return IDS_ASH_SCREENSHOT_NOTIFICATION_TEXT_FAIL;
  }
}

void PrepareWritableFileCallback(
    const ChromeScreenshotGrabber::FileCallback& callback,
    drive::FileError error,
    const base::FilePath& local_path) {
  callback.Run(error == drive::FILE_ERROR_OK
                   ? ui::ScreenshotGrabberDelegate::FILE_SUCCESS
                   : ui::ScreenshotGrabberDelegate::FILE_CREATE_FAILED,
               local_path);
}

void EnsureDirectoryExistsCallback(
    const ChromeScreenshotGrabber::FileCallback& callback,
    Profile* profile,
    const base::FilePath& path,
    drive::FileError error) {
  // It is okay to fail with FILE_ERROR_EXISTS since anyway the directory
  // of the target file exists.
  if (error == drive::FILE_ERROR_OK || error == drive::FILE_ERROR_EXISTS) {
    drive::util::PrepareWritableFileAndRun(
        profile, path, base::Bind(&PrepareWritableFileCallback, callback));
  } else {
    LOG(ERROR) << "Failed to ensure the existence of the specified directory "
               << "in Google Drive: " << error;
    content::BrowserThread::GetBlockingPool()->PostTask(
        FROM_HERE,
        base::Bind(callback,
                   ui::ScreenshotGrabberDelegate::FILE_CHECK_DIR_FAILED,
                   base::FilePath()));
  }
}
#endif

bool ScreenshotsDisabled() {
  return g_browser_process->local_state()->GetBoolean(
      prefs::kDisableScreenshots);
}

bool ShouldUse24HourClock() {
#if defined(OS_CHROMEOS)
  Profile* profile = ProfileManager::GetActiveUserProfile();
  if (profile) {
    return profile->GetPrefs()->GetBoolean(prefs::kUse24HourClock);
  }
#endif
  return base::GetHourClockType() == base::k24HourClock;
}

bool GetScreenshotDirectory(base::FilePath* directory) {
  bool is_logged_in = true;

#if defined(OS_CHROMEOS)
  is_logged_in = chromeos::LoginState::Get()->IsUserLoggedIn();
#endif

  if (is_logged_in) {
    DownloadPrefs* download_prefs = DownloadPrefs::FromBrowserContext(
        ProfileManager::GetActiveUserProfile());
    *directory = download_prefs->DownloadPath();
  } else {
    if (!base::GetTempDir(directory)) {
      LOG(ERROR) << "Failed to find temporary directory.";
      return false;
    }
  }
  return true;
}

std::string GetScreenshotBaseFilename() {
  base::Time::Exploded now;
  base::Time::Now().LocalExplode(&now);

  // We don't use base/i18n/time_formatting.h here because it doesn't
  // support our format.  Don't use ICU either to avoid i18n file names
  // for non-English locales.
  // TODO(mukai): integrate this logic somewhere time_formatting.h
  std::string file_name = base::StringPrintf(
      "Screenshot %d-%02d-%02d at ", now.year, now.month, now.day_of_month);

  if (ShouldUse24HourClock()) {
    file_name.append(
        base::StringPrintf("%02d.%02d.%02d", now.hour, now.minute, now.second));
  } else {
    int hour = now.hour;
    if (hour > 12) {
      hour -= 12;
    } else if (hour == 0) {
      hour = 12;
    }
    file_name.append(
        base::StringPrintf("%d.%02d.%02d ", hour, now.minute, now.second));
    file_name.append((now.hour >= 12) ? "PM" : "AM");
  }

  return file_name;
}

}  // namespace

ChromeScreenshotGrabber::ChromeScreenshotGrabber()
    : screenshot_grabber_(new ui::ScreenshotGrabber(
          this,
          content::BrowserThread::GetBlockingPool()
              ->GetTaskRunnerWithShutdownBehavior(
                  base::SequencedWorkerPool::SKIP_ON_SHUTDOWN))),
      profile_for_test_(NULL) {
  screenshot_grabber_->AddObserver(this);
}

ChromeScreenshotGrabber::~ChromeScreenshotGrabber() {
  screenshot_grabber_->RemoveObserver(this);
}

void ChromeScreenshotGrabber::HandleTakeScreenshotForAllRootWindows() {
  if (ScreenshotsDisabled()) {
    screenshot_grabber_->NotifyScreenshotCompleted(
        ui::ScreenshotGrabberObserver::SCREENSHOTS_DISABLED, base::FilePath());
    return;
  }

  base::FilePath screenshot_directory;
  if (!GetScreenshotDirectory(&screenshot_directory)) {
    screenshot_grabber_->NotifyScreenshotCompleted(
        ui::ScreenshotGrabberObserver::SCREENSHOT_GET_DIR_FAILED,
        base::FilePath());
    return;
  }

  std::string screenshot_basename = GetScreenshotBaseFilename();
  aura::Window::Windows root_windows = ash::Shell::GetAllRootWindows();
  // Reorder root_windows to take the primary root window's snapshot at first.
  aura::Window* primary_root = ash::Shell::GetPrimaryRootWindow();
  if (*(root_windows.begin()) != primary_root) {
    root_windows.erase(
        std::find(root_windows.begin(), root_windows.end(), primary_root));
    root_windows.insert(root_windows.begin(), primary_root);
  }
  std::vector<base::FilePath> filenames;
  for (size_t i = 0; i < root_windows.size(); ++i) {
    aura::Window* root_window = root_windows[i];
    std::string basename = screenshot_basename;
    gfx::Rect rect = root_window->bounds();
    if (root_windows.size() > 1)
      basename += base::StringPrintf(" - Display %d", static_cast<int>(i + 1));
    base::FilePath screenshot_path =
        screenshot_directory.AppendASCII(basename + ".png");
    screenshot_grabber_->TakeScreenshot(root_window, rect, screenshot_path);
  }
  content::RecordAction(base::UserMetricsAction("Screenshot_TakeFull"));
}

void ChromeScreenshotGrabber::HandleTakePartialScreenshot(
    aura::Window* window,
    const gfx::Rect& rect) {
  if (ScreenshotsDisabled()) {
    screenshot_grabber_->NotifyScreenshotCompleted(
        ui::ScreenshotGrabberObserver::SCREENSHOTS_DISABLED, base::FilePath());
    return;
  }

  base::FilePath screenshot_directory;
  if (!GetScreenshotDirectory(&screenshot_directory)) {
    screenshot_grabber_->NotifyScreenshotCompleted(
        ui::ScreenshotGrabberObserver::SCREENSHOT_GET_DIR_FAILED,
        base::FilePath());
    return;
  }

  base::FilePath screenshot_path =
      screenshot_directory.AppendASCII(GetScreenshotBaseFilename() + ".png");
  screenshot_grabber_->TakeScreenshot(window, rect, screenshot_path);
  content::RecordAction(base::UserMetricsAction("Screenshot_TakePartial"));
}

bool ChromeScreenshotGrabber::CanTakeScreenshot() {
  return screenshot_grabber_->CanTakeScreenshot();
}

void ChromeScreenshotGrabber::PrepareFileAndRunOnBlockingPool(
    const base::FilePath& path,
    scoped_refptr<base::TaskRunner> blocking_task_runner,
    const FileCallback& callback) {
#if defined(OS_CHROMEOS)
  Profile* profile = ProfileManager::GetActiveUserProfile();
  if (drive::util::IsUnderDriveMountPoint(path)) {
    drive::util::EnsureDirectoryExists(
        profile, path.DirName(),
        base::Bind(&EnsureDirectoryExistsCallback, callback, profile, path));
    return;
  }
#endif
  ui::ScreenshotGrabberDelegate::PrepareFileAndRunOnBlockingPool(
      path, blocking_task_runner, callback);
}

void ChromeScreenshotGrabber::OnScreenshotCompleted(
    ui::ScreenshotGrabberObserver::Result result,
    const base::FilePath& screenshot_path) {
#if defined(OS_CHROMEOS)
  // Do not show a notification that a screenshot was taken while no user is
  // logged in, since it is confusing for the user to get a message about it
  // after he logs in (crbug.com/235217).
  if (!chromeos::LoginState::Get()->IsUserLoggedIn())
    return;

  // TODO(sschmitz): make this work for Windows.
  NotifierStateTracker* const notifier_state_tracker =
      NotifierStateTrackerFactory::GetForProfile(GetProfile());
  if (notifier_state_tracker->IsNotifierEnabled(message_center::NotifierId(
          message_center::NotifierId::SYSTEM_COMPONENT,
          ash::system_notifier::kNotifierScreenshot))) {
    scoped_ptr<Notification> notification(
        CreateNotification(result, screenshot_path));
    g_browser_process->notification_ui_manager()->Add(*notification,
                                                      GetProfile());
  }
#endif
}

#if defined(OS_CHROMEOS)
Notification* ChromeScreenshotGrabber::CreateNotification(
    ui::ScreenshotGrabberObserver::Result screenshot_result,
    const base::FilePath& screenshot_path) {
  const std::string notification_id(kNotificationId);
  // We cancel a previous screenshot notification, if any, to ensure we get
  // a fresh notification pop-up.
  g_browser_process->notification_ui_manager()->CancelById(
      notification_id, NotificationUIManager::GetProfileID(GetProfile()));
  bool success =
      (screenshot_result == ui::ScreenshotGrabberObserver::SCREENSHOT_SUCCESS);
  message_center::RichNotificationData optional_field;
  if (success) {
    const base::string16 label = l10n_util::GetStringUTF16(
        IDS_MESSAGE_CENTER_NOTIFICATION_BUTTON_COPY_SCREENSHOT_TO_CLIPBOARD);
    optional_field.buttons.push_back(message_center::ButtonInfo(label));
  }
  return new Notification(
      message_center::NOTIFICATION_TYPE_SIMPLE,
      l10n_util::GetStringUTF16(
          GetScreenshotNotificationTitle(screenshot_result)),
      l10n_util::GetStringUTF16(
          GetScreenshotNotificationText(screenshot_result)),
      ui::ResourceBundle::GetSharedInstance().GetImageNamed(
          IDR_SCREENSHOT_NOTIFICATION_ICON),
      message_center::NotifierId(message_center::NotifierId::SYSTEM_COMPONENT,
                                 ash::system_notifier::kNotifierScreenshot),
      l10n_util::GetStringUTF16(IDS_MESSAGE_CENTER_NOTIFIER_SCREENSHOT_NAME),
      GURL(kNotificationOriginUrl), notification_id, optional_field,
      new ScreenshotGrabberNotificationDelegate(success, GetProfile(),
                                                screenshot_path));
}
#endif

void ChromeScreenshotGrabber::SetProfileForTest(Profile* profile) {
  profile_for_test_ = profile;
}

Profile* ChromeScreenshotGrabber::GetProfile() {
  return profile_for_test_ ? profile_for_test_
                           : ProfileManager::GetActiveUserProfile();
}