// 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/extensions/api/tabs/windows_event_router.h"

#include "base/values.h"
#include "chrome/browser/chrome_notification_types.h"
#include "chrome/browser/extensions/extension_service.h"
#include "chrome/browser/extensions/extension_util.h"
#include "chrome/browser/extensions/window_controller.h"
#include "chrome/browser/extensions/window_controller_list.h"
#include "chrome/browser/profiles/profile.h"
#include "chrome/common/extensions/api/windows.h"
#include "chrome/common/extensions/extension_constants.h"
#include "content/public/browser/notification_service.h"
#include "extensions/browser/event_router.h"
#include "extensions/common/constants.h"

using content::BrowserContext;

namespace extensions {

namespace windows = extensions::api::windows;

WindowsEventRouter::WindowsEventRouter(Profile* profile)
    : profile_(profile),
      focused_profile_(NULL),
      focused_window_id_(extension_misc::kUnknownWindowId) {
  DCHECK(!profile->IsOffTheRecord());

  WindowControllerList::GetInstance()->AddObserver(this);
  // Needed for when no suitable window can be passed to an extension as the
  // currently focused window. On Mac (even in a toolkit-views build) always
  // rely on the notification sent by AppControllerMac after AppKit sends
  // NSWindowDidBecomeKeyNotification and there is no [NSApp keyWindow]. This
  // allows windows not created by toolkit-views to be tracked.
  // TODO(tapted): Remove the ifdefs (and NOTIFICATION_NO_KEY_WINDOW) when
  // Chrome on Mac only makes windows with toolkit-views.
#if defined(OS_MACOSX)
  registrar_.Add(this, chrome::NOTIFICATION_NO_KEY_WINDOW,
                 content::NotificationService::AllSources());
#elif defined(TOOLKIT_VIEWS)
  views::WidgetFocusManager::GetInstance()->AddFocusChangeListener(this);
#else
#error Unsupported
#endif
}

WindowsEventRouter::~WindowsEventRouter() {
  WindowControllerList::GetInstance()->RemoveObserver(this);
#if !defined(OS_MACOSX)
  views::WidgetFocusManager::GetInstance()->RemoveFocusChangeListener(this);
#endif
}

void WindowsEventRouter::OnWindowControllerAdded(
    WindowController* window_controller) {
  if (!profile_->IsSameProfile(window_controller->profile()))
    return;

  scoped_ptr<base::ListValue> args(new base::ListValue());
  base::DictionaryValue* window_dictionary =
      window_controller->CreateWindowValue();
  args->Append(window_dictionary);
  DispatchEvent(windows::OnCreated::kEventName, window_controller->profile(),
                args.Pass());
}

void WindowsEventRouter::OnWindowControllerRemoved(
    WindowController* window_controller) {
  if (!profile_->IsSameProfile(window_controller->profile()))
    return;

  int window_id = window_controller->GetWindowId();
  scoped_ptr<base::ListValue> args(new base::ListValue());
  args->Append(new base::FundamentalValue(window_id));
  DispatchEvent(windows::OnRemoved::kEventName,
                window_controller->profile(),
                args.Pass());
}

#if !defined(OS_MACOSX)
void WindowsEventRouter::OnNativeFocusChanged(gfx::NativeView focused_now) {
  if (!focused_now)
    OnActiveWindowChanged(NULL);
}
#endif

void WindowsEventRouter::Observe(
    int type,
    const content::NotificationSource& source,
    const content::NotificationDetails& details) {
#if defined(OS_MACOSX)
  if (chrome::NOTIFICATION_NO_KEY_WINDOW == type) {
      OnActiveWindowChanged(NULL);
      return;
  }
#endif
}

static bool WillDispatchWindowFocusedEvent(BrowserContext* new_active_context,
                                           int window_id,
                                           BrowserContext* context,
                                           const Extension* extension,
                                           base::ListValue* event_args) {
  // When switching between windows in the default and incognito profiles,
  // dispatch WINDOW_ID_NONE to extensions whose profile lost focus that
  // can't see the new focused window across the incognito boundary.
  // See crbug.com/46610.
  if (new_active_context && new_active_context != context &&
      !util::CanCrossIncognito(extension, context)) {
    event_args->Clear();
    event_args->Append(new base::FundamentalValue(
        extension_misc::kUnknownWindowId));
  } else {
    event_args->Clear();
    event_args->Append(new base::FundamentalValue(window_id));
  }
  return true;
}

void WindowsEventRouter::OnActiveWindowChanged(
    WindowController* window_controller) {
  Profile* window_profile = NULL;
  int window_id = extension_misc::kUnknownWindowId;
  if (window_controller &&
      profile_->IsSameProfile(window_controller->profile())) {
    window_profile = window_controller->profile();
    window_id = window_controller->GetWindowId();
  }

  if (focused_window_id_ == window_id)
    return;

  // window_profile is either the default profile for the active window, its
  // incognito profile, or NULL iff the previous profile is losing focus.
  focused_profile_ = window_profile;
  focused_window_id_ = window_id;

  scoped_ptr<Event> event(new Event(windows::OnFocusChanged::kEventName,
                                    make_scoped_ptr(new base::ListValue())));
  event->will_dispatch_callback =
      base::Bind(&WillDispatchWindowFocusedEvent,
                 static_cast<BrowserContext*>(window_profile),
                 window_id);
  EventRouter::Get(profile_)->BroadcastEvent(event.Pass());
}

void WindowsEventRouter::DispatchEvent(const std::string& event_name,
                                      Profile* profile,
                                      scoped_ptr<base::ListValue> args) {
  scoped_ptr<Event> event(new Event(event_name, args.Pass()));
  event->restrict_to_browser_context = profile;
  EventRouter::Get(profile)->BroadcastEvent(event.Pass());
}

}  // namespace extensions