// 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.

#ifndef CONTENT_RENDERER_RENDER_VIEW_IMPL_H_
#define CONTENT_RENDERER_RENDER_VIEW_IMPL_H_

#include <stddef.h>
#include <stdint.h>

#include <map>
#include <memory>
#include <set>
#include <string>
#include <vector>

#include "base/containers/id_map.h"
#include "base/gtest_prod_util.h"
#include "base/macros.h"
#include "base/observer_list.h"
#include "base/process/process.h"
#include "base/single_thread_task_runner.h"
#include "base/strings/string16.h"
#include "base/strings/string_piece.h"
#include "base/timer/timer.h"
#include "build/build_config.h"
#include "cc/input/browser_controls_state.h"
#include "content/common/content_export.h"
#include "content/common/frame_message_enums.h"
#include "content/public/common/browser_controls_state.h"
#include "content/public/common/drop_data.h"
#include "content/public/common/page_zoom.h"
#include "content/public/common/referrer.h"
#include "content/public/common/renderer_preference_watcher.mojom.h"
#include "content/public/common/renderer_preferences.h"
#include "content/public/common/web_preferences.h"
#include "content/public/renderer/render_view.h"
#include "content/renderer/render_frame_impl.h"
#include "content/renderer/render_widget.h"
#include "content/renderer/render_widget_owner_delegate.h"
#include "ipc/ipc_platform_file.h"
#include "mojo/public/cpp/bindings/interface_ptr_set.h"
#include "third_party/blink/public/common/dom_storage/session_storage_namespace_id.h"
#include "third_party/blink/public/platform/web_input_event.h"
#include "third_party/blink/public/platform/web_scoped_virtual_time_pauser.h"
#include "third_party/blink/public/platform/web_security_origin.h"
#include "third_party/blink/public/web/web_ax_object.h"
#include "third_party/blink/public/web/web_console_message.h"
#include "third_party/blink/public/web/web_element.h"
#include "third_party/blink/public/web/web_frame_widget.h"
#include "third_party/blink/public/web/web_history_item.h"
#include "third_party/blink/public/web/web_navigation_type.h"
#include "third_party/blink/public/web/web_node.h"
#include "third_party/blink/public/web/web_view_client.h"
#include "third_party/blink/public/web/web_widget_client.h"
#include "ui/base/window_open_disposition.h"
#include "ui/gfx/geometry/rect.h"
#include "ui/gfx/geometry/rect_f.h"
#include "ui/surface/transport_dib.h"

#if defined(OS_ANDROID)
#include "content/renderer/android/renderer_date_time_picker.h"
#endif

namespace blink {
class WebDateTimeChooserCompletion;
class WebGestureEvent;
class WebMouseEvent;
class WebURLRequest;
struct WebDateTimeChooserParams;
struct WebPluginAction;
struct WebWindowFeatures;
}  // namespace blink

namespace content {
class RendererDateTimePicker;
class RenderViewImplTest;
class RenderViewObserver;
class RenderViewTest;

namespace mojom {
class CreateViewParams;
}

// RenderViewImpl (the implementation of RenderView) is the renderer process
// object that owns the blink frame tree.
//
// Each top-level web container has a frame tree, and thus a RenderViewImpl.
// Typically such a container is a browser tab, or a tab-less window. It can
// also be other cases such as a background page or extension.
//
// Under site isolation, frames in the main frame's tree may be moved out
// to a separate frame tree (possibly in another process), leaving remote
// placeholders behind. Each such frame tree also includes a RenderViewImpl as
// the owner of it. Thus a tab may have multiple RenderViewImpls, one for the
// main frame, and one for each other frame tree generated.
//
// The RenderViewImpl manages a WebView object from blink, which hosts the
// web page and a blink frame tree. If the main frame (root of the tree) is
// a local frame for this view, then it also manages a RenderWidget for the
// main frame.
//
// TODO(419087): That RenderWidget should be managed by the main frame itself.
class CONTENT_EXPORT RenderViewImpl : private RenderWidget,
                                      public blink::WebViewClient,
                                      public RenderWidgetOwnerDelegate,
                                      public RenderView {
 public:
  // Creates a new RenderView. Note that if the original opener has been closed,
  // |params.window_was_created_with_opener| will be true and
  // |params.opener_frame_route_id| will be MSG_ROUTING_NONE.
  // When |params.proxy_routing_id| instead of |params.main_frame_routing_id| is
  // specified, a RenderFrameProxy will be created for this RenderView's main
  // RenderFrame.
  // The opener should provide a non-null value for |show_callback| if it needs
  // to send an additional IPC to finish making this view visible.
  static RenderViewImpl* Create(
      CompositorDependencies* compositor_deps,
      mojom::CreateViewParamsPtr params,
      RenderWidget::ShowCallback show_callback,
      scoped_refptr<base::SingleThreadTaskRunner> task_runner);

  // Used by content_layouttest_support to hook into the creation of
  // RenderViewImpls.
  static void InstallCreateHook(RenderViewImpl* (*create_render_view_impl)(
      CompositorDependencies* compositor_deps,
      const mojom::CreateViewParams&));

  // Returns the RenderViewImpl containing the given WebView.
  static RenderViewImpl* FromWebView(blink::WebView* webview);

  // Returns the RenderViewImpl for the given routing ID.
  static RenderViewImpl* FromRoutingID(int routing_id);

  // May return NULL when the view is closing.
  blink::WebView* webview();
  const blink::WebView* webview() const;

  // Returns the RenderWidget for this RenderView.
  RenderWidget* GetWidget();

  const WebPreferences& webkit_preferences() const {
    return webkit_preferences_;
  }

  const RendererPreferences& renderer_preferences() const {
    return renderer_preferences_;
  }

  void set_send_content_state_immediately(bool value) {
    send_content_state_immediately_ = value;
  }

  // Functions to add and remove observers for this object.
  void AddObserver(RenderViewObserver* observer);
  void RemoveObserver(RenderViewObserver* observer);

#if defined(OS_ANDROID)
  void DismissDateTimeDialog();
#endif

  // Sets the zoom level and notifies observers.
  void SetZoomLevel(double zoom_level);

  double page_zoom_level() {
    return page_zoom_level_;
  }

  // Sets page-level focus in this view and notifies plugins and Blink's
  // FocusController.
  void SetFocus(bool enable);

  // Attaches a WebFrameWidget that will provide a WebFrameWidget interface to
  // the WebView. Called as part of initialization or when the main frame
  // RenderWidget is unfrozen, to connect it to the new local main frame.
  void AttachWebFrameWidget(blink::WebFrameWidget* frame_widget);
  // Detaches the current WebFrameWidget, disconnecting it from the main frame.
  // Called when the RenderWidget is being frozen, because the local main
  // frame is going away.
  void DetachWebFrameWidget();

  // Starts a timer to send an UpdateState message on behalf of |frame|, if the
  // timer isn't already running. This allows multiple state changing events to
  // be coalesced into one update.
  void StartNavStateSyncTimerIfNecessary(RenderFrameImpl* frame);

  // A popup widget opened by this view needs to be shown.
  void ShowCreatedPopupWidget(RenderWidget* popup_widget,
                              blink::WebNavigationPolicy policy,
                              const gfx::Rect& initial_rect);
  // A RenderWidgetFullscreen widget opened by this view needs to be shown.
  void ShowCreatedFullscreenWidget(RenderWidget* fullscreen_widget,
                                   blink::WebNavigationPolicy policy,
                                   const gfx::Rect& initial_rect);

  // Returns the length of the session history of this RenderView. Note that
  // this only coincides with the actual length of the session history if this
  // RenderView is the currently active RenderView of a WebContents.
  unsigned GetLocalSessionHistoryLengthForTesting() const;

  // Invokes OnSetFocus and marks the widget as active depending on the value
  // of |enable|. This is used for layout tests that need to control the focus
  // synchronously from the renderer.
  void SetFocusAndActivateForTesting(bool enable);

  void DidCommitProvisionalHistoryLoad();

  // Registers a watcher to observe changes in the RendererPreferences.
  void RegisterRendererPreferenceWatcherForWorker(
      mojom::RendererPreferenceWatcherPtr watcher);

  // IPC::Listener implementation (via RenderWidget inheritance).
  bool OnMessageReceived(const IPC::Message& msg) override;

  // blink::WebViewClient implementation --------------------------------------

  blink::WebView* CreateView(blink::WebLocalFrame* creator,
                             const blink::WebURLRequest& request,
                             const blink::WebWindowFeatures& features,
                             const blink::WebString& frame_name,
                             blink::WebNavigationPolicy policy,
                             bool suppress_opener,
                             blink::WebSandboxFlags sandbox_flags,
                             const blink::SessionStorageNamespaceId&
                                 session_storage_namespace_id) override;
  blink::WebWidget* CreatePopup(blink::WebLocalFrame* creator) override;
  base::StringPiece GetSessionStorageNamespaceId() override;
  void PrintPage(blink::WebLocalFrame* frame) override;
  void SetValidationMessageDirection(base::string16* main_text,
                                     blink::WebTextDirection main_text_hint,
                                     base::string16* sub_text,
                                     blink::WebTextDirection sub_text_hint);
  void SetMouseOverURL(const blink::WebURL& url) override;
  void SetKeyboardFocusURL(const blink::WebURL& url) override;
  bool AcceptsLoadDrops() override;
  void FocusNext() override;
  void FocusPrevious() override;
  void FocusedNodeChanged(const blink::WebNode& fromNode,
                          const blink::WebNode& toNode) override;
  bool CanUpdateLayout() override;
  void DidUpdateMainFrameLayout() override;
  blink::WebString AcceptLanguages() override;
  void NavigateBackForwardSoon(int offset, bool has_user_gesture) override;
  int HistoryBackListCount() override;
  int HistoryForwardListCount() override;
  void ZoomLimitsChanged(double minimum_level, double maximum_level) override;
  void PageScaleFactorChanged() override;
  virtual double zoomLevelToZoomFactor(double zoom_level) const;
  virtual double zoomFactorToZoomLevel(double factor) const;
  void PageImportanceSignalsChanged() override;
  void DidAutoResize(const blink::WebSize& newSize) override;
  blink::WebRect RootWindowRect() override;
  void DidFocus(blink::WebLocalFrame* calling_frame) override;
  blink::WebScreenInfo GetScreenInfo() override;
  bool CanHandleGestureEvent() override;
  blink::WebWidgetClient* WidgetClient() override;

#if defined(OS_ANDROID)
  // Only used on Android since all other platforms implement
  // date and time input fields using MULTIPLE_FIELDS_UI
  bool OpenDateTimeChooser(const blink::WebDateTimeChooserParams&,
                           blink::WebDateTimeChooserCompletion*) override;
#endif

  // RenderView implementation -------------------------------------------------

  bool Send(IPC::Message* message) override;
  RenderFrameImpl* GetMainRenderFrame() override;
  int GetRoutingID() const override;
  gfx::Size GetSize() const override;
  float GetDeviceScaleFactor() const override;
  float GetZoomLevel() const override;
  const WebPreferences& GetWebkitPreferences() override;
  void SetWebkitPreferences(const WebPreferences& preferences) override;
  blink::WebView* GetWebView() override;
  blink::WebFrameWidget* GetWebFrameWidget() override;
  bool GetContentStateImmediately() const override;
  void SetEditCommandForNextKeyEvent(const std::string& name,
                                     const std::string& value) override;
  void ClearEditCommands() override;
  const std::string& GetAcceptLanguages() const override;
  void UpdateBrowserControlsState(BrowserControlsState constraints,
                                  BrowserControlsState current,
                                  bool animate) override;
#if defined(OS_ANDROID) || defined(OS_CHROMEOS)
  virtual void didScrollWithKeyboard(const blink::WebSize& delta);
#endif
  void ConvertViewportToWindowViaWidget(blink::WebRect* rect) override;
  gfx::RectF ElementBoundsInWindow(const blink::WebElement& element) override;

  // Please do not add your stuff randomly to the end here. If there is an
  // appropriate section, add it there. If not, there are some random functions
  // nearer to the top you can add it to.

  base::WeakPtr<RenderViewImpl> GetWeakPtr() {
    return weak_ptr_factory_.GetWeakPtr();
  }

  bool renderer_wide_named_frame_lookup() {
    return renderer_wide_named_frame_lookup_;
  }
  void UpdateZoomLevel(double zoom_level);
  void OnAnimateDoubleTapZoomInMainFrame(const blink::WebPoint& point,
                                         const blink::WebRect& rect_to_zoom);

 protected:
  RenderViewImpl(CompositorDependencies* compositor_deps,
                 const mojom::CreateViewParams& params);

  void Initialize(mojom::CreateViewParamsPtr params,
                  RenderWidget::ShowCallback show_callback,
                  scoped_refptr<base::SingleThreadTaskRunner> task_runner);

  // Do not delete directly.  This class is reference counted.
  ~RenderViewImpl() override;

  // Called when Page visibility is changed, to update the View/Page in blink.
  // This is separate from the IPC handlers as tests may call this and need to
  // be able to specify |initial_setting| where IPC handlers do not.
  void ApplyPageHidden(bool hidden, bool initial_setting);

 private:
  // For unit tests.
  friend class DevToolsAgentTest;
  friend class RenderViewImplScaleFactorTest;
  friend class RenderViewImplTest;
  friend class RenderViewTest;
  friend class RendererAccessibilityTest;

  // TODO(nasko): Temporarily friend RenderFrameImpl, so we don't duplicate
  // utility functions needed in both classes, while we move frame specific
  // code away from this class.
  friend class RenderFrameImpl;

  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, RenderFrameMessageAfterDetach);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, BeginNavigationForWebUI);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest,
                           DidFailProvisionalLoadWithErrorForError);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest,
                           DidFailProvisionalLoadWithErrorForCancellation);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, ImeComposition);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, InsertCharacters);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, JSBlockSentAfterPageLoad);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, LastCommittedUpdateState);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, OnHandleKeyboardEvent);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, OnImeTypeChanged);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, OnNavStateChanged);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, OnUpdateWebPreferences);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest,
                           SetEditableSelectionAndComposition);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, StaleNavigationsIgnored);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest,
                           DontIgnoreBackAfterNavEntryLimit);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, UpdateTargetURLWithInvalidURL);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest,
                           GetCompositionCharacterBoundsTest);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, OnNavigationHttpPost);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, UpdateDSFAfterSwapIn);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest,
                           BeginNavigationHandlesAllTopLevel);
#if defined(OS_MACOSX)
  FRIEND_TEST_ALL_PREFIXES(RenderViewTest, MacTestCmdUp);
#endif
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, SetHistoryLengthAndOffset);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, NavigateFrame);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, BasicRenderFrame);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, TextInputTypeWithPepper);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest,
                           MessageOrderInDidChangeSelection);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, SendCandidateWindowEvents);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, RenderFrameClearedAfterClose);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest, PaintAfterSwapOut);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplTest,
                           SetZoomLevelAfterCrossProcessNavigation);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplScaleFactorTest,
                           ConverViewportToScreenWithZoomForDSF);
  FRIEND_TEST_ALL_PREFIXES(RenderViewImplEnableZoomForDSFTest,
                           GetCompositionCharacterBoundsTest);

  enum ErrorPageType {
    DNS_ERROR,
    HTTP_404,
    CONNECTION_ERROR,
  };

  // RenderWidget public API that should no longer go through RenderView.
  using RenderWidget::routing_id;

  // RenderWidgetOwnerDelegate implementation ----------------------------------

  blink::WebWidget* GetWebWidgetForWidget() const override;
  bool RenderWidgetWillHandleMouseEventForWidget(
      const blink::WebMouseEvent& event) override;
  void SetActiveForWidget(bool active) override;
  bool SupportsMultipleWindowsForWidget() override;
  void DidHandleGestureEventForWidget(
      const blink::WebGestureEvent& event) override;
  void DidCloseWidget() override;
  void ApplyNewSizeForWidget(const gfx::Size& old_size,
                             const gfx::Size& new_size) override;
  void ApplyNewDisplayModeForWidget(
      const blink::WebDisplayMode& new_display_mode) override;
  void ApplyAutoResizeLimitsForWidget(const gfx::Size& min_size,
                                      const gfx::Size& max_size) override;
  void DisableAutoResizeForWidget() override;
  void ScrollFocusedNodeIntoViewForWidget() override;
  void DidReceiveSetFocusEventForWidget() override;
  void DidChangeFocusForWidget() override;
  void DidCommitCompositorFrameForWidget() override;
  void DidCompletePageScaleAnimationForWidget() override;
  void ResizeWebWidgetForWidget(
      const gfx::Size& size,
      float top_controls_height,
      float bottom_controls_height,
      bool browser_controls_shrink_blink_size) override;
  void RequestScheduleAnimationForWidget() override;
  void SetScreenMetricsEmulationParametersForWidget(
      bool enabled,
      const blink::WebDeviceEmulationParams& params) override;

  // Old WebLocalFrameClient implementations
  // ----------------------------------------

  // RenderViewImpl used to be a WebLocalFrameClient, but now RenderFrameImpl is
  // the WebLocalFrameClient. However, many implementations of
  // WebLocalFrameClient methods still live here and are called from
  // RenderFrameImpl. These implementations are to be moved to RenderFrameImpl
  // <http://crbug.com/361761>.

  static Referrer GetReferrerFromRequest(
      blink::WebFrame* frame,
      const blink::WebURLRequest& request);

  static WindowOpenDisposition NavigationPolicyToDisposition(
      blink::WebNavigationPolicy policy);

  // IPC message handlers ------------------------------------------------------
  //
  // The documentation for these functions should be in
  // content/common/*_messages.h for the message that the function is handling.
  void OnExecuteEditCommand(const std::string& name, const std::string& value);
  void OnAllowScriptToClose(bool script_can_close);
  void OnCancelDownload(int32_t download_id);
  void OnClosePage();

  void OnDeterminePageLanguage();
  void OnDisableScrollbarsForSmallWindows(
      const gfx::Size& disable_scrollbars_size_limit);
  void OnEnablePreferredSizeChangedMode();
  void OnPluginActionAt(const gfx::Point& location,
                        const blink::WebPluginAction& action);
  void OnMoveOrResizeStarted();
  void OnExitFullscreen();
  void OnSetHistoryOffsetAndLength(int history_offset, int history_length);
  void OnSetInitialFocus(bool reverse);
  void OnSetRendererPrefs(const RendererPreferences& renderer_prefs);
  void OnSetWebUIProperty(const std::string& name, const std::string& value);
  void OnSuppressDialogsUntilSwapOut();
  void OnUpdateTargetURLAck();
  void OnUpdateWebPreferences(const WebPreferences& prefs);
  void OnSetPageScale(float page_scale_factor);
  void OnAudioStateChanged(bool is_audio_playing);
  void OnPausePageScheduledTasks(bool paused);

  // Page message handlers -----------------------------------------------------
  void OnUpdateWindowScreenRect(gfx::Rect window_screen_rect);
  void OnPageWasHidden();
  void OnPageWasShown();
  void OnUpdateScreenInfo(const ScreenInfo& screen_info);
  void SetPageFrozen(bool frozen);

  // Adding a new message handler? Please add it in alphabetical order above
  // and put it in the same position in the .cc file.

  // Misc private functions ----------------------------------------------------
  // Check whether the preferred size has changed. This should only be called
  // with up-to-date layout.
  void UpdatePreferredSize();

#if defined(OS_ANDROID)
  // Make the video capture devices (e.g. webcam) stop/resume delivering video
  // frames to their clients, depending on flag |suspend|. This is called in
  // response to a RenderView PageHidden/Shown().
  void SuspendVideoCaptureDevices(bool suspend);
#endif

#if defined(OS_MACOSX)
  void UpdateFontRenderingFromRendererPrefs() {}
#else
  void UpdateFontRenderingFromRendererPrefs();
#endif

  // In OOPIF-enabled modes, this tells each RenderFrame with a pending state
  // update to inform the browser process.
  void SendFrameStateUpdates();

  // Update the target url and tell the browser that the target URL has changed.
  // If |url| is empty, show |fallback_url|.
  void UpdateTargetURL(const GURL& url, const GURL& fallback_url);

  // RenderFrameImpl accessible state ------------------------------------------
  // The following section is the set of methods that RenderFrameImpl needs
  // to access RenderViewImpl state. The set of state variables are page-level
  // specific, so they don't belong in RenderFrameImpl and should remain in
  // this object.
  base::ObserverList<RenderViewObserver>::Unchecked& observers() {
    return observers_;
  }

// Platform specific theme preferences if any are updated here.
#if defined(OS_WIN)
  void UpdateThemePrefs();
#elif defined(OS_POSIX) || defined(OS_FUCHSIA)
  void UpdateThemePrefs() {}
#endif

  // ---------------------------------------------------------------------------
  // ADDING NEW FUNCTIONS? Please keep private functions alphabetized and put
  // it in the same order in the .cc file as it was in the header.
  // ---------------------------------------------------------------------------

  // Routing ID that allows us to communicate with the corresponding
  // RenderViewHost in the parent browser process.
  const int32_t routing_id_;

  // Whether lookup of frames in the created RenderView (e.g. lookup via
  // window.open or via <a target=...>) should be renderer-wide (i.e. going
  // beyond the usual opener-relationship-based BrowsingInstance boundaries).
  const bool renderer_wide_named_frame_lookup_;

  // Settings ------------------------------------------------------------------

  WebPreferences webkit_preferences_;
  RendererPreferences renderer_preferences_;
  // These are observing changes in |renderer_preferences_|. This is used for
  // keeping WorkerFetchContext in sync.
  mojo::InterfacePtrSet<mojom::RendererPreferenceWatcher>
      renderer_preference_watchers_;

  // Whether content state (such as form state, scroll position and page
  // contents) should be sent to the browser immediately. This is normally
  // false, but set to true by some tests.
  bool send_content_state_immediately_ = false;

  // If true, we send IPC messages when |preferred_size_| changes.
  bool send_preferred_size_changes_ = false;

  // Whether the preferred size may have changed and |UpdatePreferredSize| needs
  // to be called.
  bool needs_preferred_size_update_ = true;

  // Loading state -------------------------------------------------------------

  // Timer used to delay the updating of nav state (see
  // StartNavStateSyncTimerIfNecessary).
  base::OneShotTimer nav_state_sync_timer_;

  // Set of RenderFrame routing IDs for frames that having pending UpdateState
  // messages to send when the next |nav_state_sync_timer_| fires.
  std::set<int> frames_with_pending_state_;

  // History list --------------------------------------------------------------

  // The offset of the current item in the history list.
  int history_list_offset_ = -1;

  // The RenderView's current impression of the history length.  This includes
  // any items that have committed in this process, but because of cross-process
  // navigations, the history may have some entries that were committed in other
  // processes.  We won't know about them until the next navigation in this
  // process.
  int history_list_length_ = 0;

  // UI state ------------------------------------------------------------------

  // The state of our target_url transmissions. When we receive a request to
  // send a URL to the browser, we set this to TARGET_INFLIGHT until an ACK
  // comes back - if a new request comes in before the ACK, we store the new
  // URL in pending_target_url_ and set the status to TARGET_PENDING. If an
  // ACK comes back and we are in TARGET_PENDING, we send the stored URL and
  // revert to TARGET_INFLIGHT.
  //
  // We don't need a queue of URLs to send, as only the latest is useful.
  enum {
    TARGET_NONE,
    TARGET_INFLIGHT,  // We have a request in-flight, waiting for an ACK
    TARGET_PENDING    // INFLIGHT + we have a URL waiting to be sent
  } target_url_status_ = TARGET_NONE;

  // The URL we show the user in the status bar. We use this to determine if we
  // want to send a new one (we do not need to send duplicates). It will be
  // equal to either |mouse_over_url_| or |focus_url_|, depending on which was
  // updated last.
  GURL target_url_;

  // The URL the user's mouse is hovering over.
  GURL mouse_over_url_;

  // The URL that has keyboard focus.
  GURL focus_url_;

  // The next target URL we want to send to the browser.
  GURL pending_target_url_;

  // Cache the old browser controls state constraints. Used when updating
  // current value only without altering the constraints.
  BrowserControlsState top_controls_constraints_ = BROWSER_CONTROLS_STATE_BOTH;

  // View ----------------------------------------------------------------------

  blink::WebView* webview_ = nullptr;

  // Cache the preferred size of the page in order to prevent sending the IPC
  // when layout() recomputes but doesn't actually change sizes.
  gfx::Size preferred_size_;

  // Used to indicate the zoom level to be used during subframe loads, since
  // they should match page zoom level.
  double page_zoom_level_ = 0;

  // Helper objects ------------------------------------------------------------

  RenderFrameImpl* main_render_frame_ = nullptr;

  // Note: RenderViewImpl is pulling double duty: it's the RenderWidget for the
  // "view", but it's also the RenderWidget for the main frame.
  blink::WebFrameWidget* frame_widget_ = nullptr;

#if defined(OS_ANDROID)
  // Android Specific ---------------------------------------------------------

  // A date/time picker object for date and time related input elements.
  std::unique_ptr<RendererDateTimePicker> date_time_picker_client_;

  // Whether this was a renderer-created or browser-created RenderView.
  bool was_created_by_renderer_ = false;
#endif

  // Misc ----------------------------------------------------------------------

  // The SessionStorage namespace that we're assigned to has an ID, and that ID
  // is passed to us upon creation.  WebKit asks for this ID upon first use and
  // uses it whenever asking the browser process to allocate new storage areas.
  blink::SessionStorageNamespaceId session_storage_namespace_id_;

  // All the registered observers.  We expect this list to be small, so vector
  // is fine.
  base::ObserverList<RenderViewObserver>::Unchecked observers_;

  blink::WebScopedVirtualTimePauser history_navigation_virtual_time_pauser_;

  // ---------------------------------------------------------------------------
  // ADDING NEW DATA? Please see if it fits appropriately in one of the above
  // sections rather than throwing it randomly at the end. If you're adding a
  // bunch of stuff, you should probably create a helper class and put your
  // data and methods on that to avoid bloating RenderView more.  You can
  // use the Observer interface to filter IPC messages and receive frame change
  // notifications.
  // ---------------------------------------------------------------------------

  base::WeakPtrFactory<RenderViewImpl> weak_ptr_factory_;

  DISALLOW_COPY_AND_ASSIGN(RenderViewImpl);
};

}  // namespace content

#endif  // CONTENT_RENDERER_RENDER_VIEW_IMPL_H_