// 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/status_icons/desktop_notification_balloon.h"

#include "base/bind.h"
#include "base/string_number_conversions.h"
#include "base/threading/thread_restrictions.h"
#include "chrome/browser/browser_process.h"
#include "chrome/browser/notifications/desktop_notification_service.h"
#include "chrome/browser/notifications/notification.h"
#include "chrome/browser/notifications/notification_delegate.h"
#include "chrome/browser/notifications/notification_ui_manager.h"
#include "chrome/browser/profiles/profile_manager.h"
#include "chrome/browser/ui/webui/web_ui_util.h"
#include "third_party/skia/include/core/SkBitmap.h"
#include "ui/gfx/image/image_skia.h"

namespace {

void CloseBalloon(const std::string& id) {
  // The browser process may have gone away during shutting down, in this case
  // notification_ui_manager() will close the balloon in its destructor.
  if (!g_browser_process)
    return;

  g_browser_process->notification_ui_manager()->CancelById(id);
}

// Prefix added to the notification ids.
const char kNotificationPrefix[] = "desktop_notification_balloon.";

// Timeout for automatically dismissing the notification balloon.
const size_t kTimeoutSeconds = 6;

class DummyNotificationDelegate : public NotificationDelegate {
 public:
  explicit DummyNotificationDelegate(const std::string& id)
      : id_(kNotificationPrefix + id) {}

  virtual void Display() OVERRIDE {
    MessageLoop::current()->PostDelayedTask(
        FROM_HERE,
        base::Bind(&CloseBalloon, id()),
        base::TimeDelta::FromSeconds(kTimeoutSeconds));
  }
  virtual void Error() OVERRIDE {}
  virtual void Close(bool by_user) OVERRIDE {}
  virtual void Click() OVERRIDE {}
  virtual std::string id() const OVERRIDE { return id_; }
  virtual content::RenderViewHost* GetRenderViewHost() const OVERRIDE {
    return NULL;
  }

 private:
  virtual ~DummyNotificationDelegate() {}

  std::string id_;
};

}  // anonymous namespace

int DesktopNotificationBalloon::id_count_ = 1;

DesktopNotificationBalloon::DesktopNotificationBalloon() {
}

DesktopNotificationBalloon::~DesktopNotificationBalloon() {
  if (!notification_id_.empty())
    CloseBalloon(notification_id_);
}

void DesktopNotificationBalloon::DisplayBalloon(const gfx::ImageSkia& icon,
                                                const string16& title,
                                                const string16& contents) {
  // Allowing IO access is required here to cover the corner case where
  // there is no last used profile and the default one is loaded.
  // IO access won't be required for normal uses.
  Profile* profile;
  {
    base::ThreadRestrictions::ScopedAllowIO allow_io;
    profile = ProfileManager::GetLastUsedProfile();
  }
  notification_id_ = DesktopNotificationService::AddIconNotification(
      GURL(), title, contents, icon, string16(),
      new DummyNotificationDelegate(base::IntToString(id_count_++)), profile);
}