import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

dom/inputmethod/HardwareKeyHandler.h

@@ -0,0 +1,224 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_HardwareKeyHandler_h_
+#define mozilla_HardwareKeyHandler_h_
+
+#include "mozilla/EventForwards.h"          // for nsEventStatus
+#include "mozilla/StaticPtr.h"
+#include "mozilla/TextEvents.h"
+#include "nsCOMPtr.h"
+#include "nsDeque.h"
+#include "nsIHardwareKeyHandler.h"
+#include "nsIWeakReferenceUtils.h"          // for nsWeakPtr
+
+class nsIContent;
+class nsINode;
+class nsIPresShell;
+class nsPIDOMWindowOuter;
+class nsPresContext;
+
+namespace mozilla {
+
+// This module will copy the events' data into its event queue for reuse
+// after receiving input-method-app's reply, so we use the following struct
+// for storing these information.
+// RefCounted<T> is a helper class for adding reference counting mechanism.
+struct KeyboardInfo : public RefCounted<KeyboardInfo>
+{
+  MOZ_DECLARE_REFCOUNTED_TYPENAME(KeyboardInfo)
+
+  nsINode* mTarget;
+  WidgetKeyboardEvent mEvent;
+  nsEventStatus mStatus;
+
+  KeyboardInfo(nsINode* aTarget,
+               WidgetKeyboardEvent& aEvent,
+               nsEventStatus aStatus)
+    : mTarget(aTarget)
+    , mEvent(aEvent)
+    , mStatus(aStatus)
+  {
+  }
+};
+
+// The following is the type-safe wrapper around nsDeque
+// for storing events' data.
+// The T must be one class that supports reference counting mechanism.
+// The EventQueueDeallocator will be called in nsDeque::~nsDeque() or
+// nsDeque::Erase() to deallocate the objects. nsDeque::Erase() will remove
+// and delete all items in the queue. See more from nsDeque.h.
+template <class T>
+class EventQueueDeallocator : public nsDequeFunctor
+{
+  virtual void* operator() (void* aObject)
+  {
+    RefPtr<T> releaseMe = dont_AddRef(static_cast<T*>(aObject));
+    return nullptr;
+  }
+};
+
+// The type-safe queue to be used to store the KeyboardInfo data
+template <class T>
+class EventQueue : private nsDeque
+{
+public:
+  EventQueue()
+    : nsDeque(new EventQueueDeallocator<T>())
+  {
+  };
+
+  ~EventQueue()
+  {
+    Clear();
+  }
+
+  inline size_t GetSize()
+  {
+    return nsDeque::GetSize();
+  }
+
+  bool IsEmpty()
+  {
+    return !nsDeque::GetSize();
+  }
+
+  inline bool Push(T* aItem)
+  {
+    MOZ_ASSERT(aItem);
+    NS_ADDREF(aItem);
+    size_t sizeBefore = GetSize();
+    nsDeque::Push(aItem);
+    if (GetSize() != sizeBefore + 1) {
+      NS_RELEASE(aItem);
+      return false;
+    }
+    return true;
+  }
+
+  inline already_AddRefed<T> PopFront()
+  {
+    RefPtr<T> rv = dont_AddRef(static_cast<T*>(nsDeque::PopFront()));
+    return rv.forget();
+  }
+
+  inline void RemoveFront()
+  {
+    RefPtr<T> releaseMe = PopFront();
+  }
+
+  inline T* PeekFront()
+  {
+    return static_cast<T*>(nsDeque::PeekFront());
+  }
+
+  void Clear()
+  {
+    while (GetSize() > 0) {
+      RemoveFront();
+    }
+  }
+};
+
+class HardwareKeyHandler : public nsIHardwareKeyHandler
+{
+public:
+  HardwareKeyHandler();
+
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIHARDWAREKEYHANDLER
+
+  static already_AddRefed<HardwareKeyHandler> GetInstance();
+
+  virtual bool ForwardKeyToInputMethodApp(nsINode* aTarget,
+                                          WidgetKeyboardEvent* aEvent,
+                                          nsEventStatus* aEventStatus) override;
+
+private:
+  virtual ~HardwareKeyHandler();
+
+  // Return true if the keypress is successfully dispatched.
+  // Otherwise, return false.
+  bool DispatchKeyPress(nsINode* aTarget,
+                        WidgetKeyboardEvent& aEvent,
+                        nsEventStatus& aStatus);
+
+  void DispatchAfterKeyEvent(nsINode* aTarget, WidgetKeyboardEvent& aEvent);
+
+  void DispatchToCurrentProcess(nsIPresShell* aPresShell,
+                                nsIContent* aTarget,
+                                WidgetKeyboardEvent& aEvent,
+                                nsEventStatus& aStatus);
+
+  bool DispatchToCrossProcess(nsINode* aTarget, WidgetKeyboardEvent& aEvent);
+
+  // This method will dispatch not only key* event to its event target,
+  // no mather it's in the current process or in its child process,
+  // but also mozbrowserafterkey* to the corresponding target if it needs.
+  // Return true if the key is successfully dispatched.
+  // Otherwise, return false.
+  bool DispatchToTargetApp(nsINode* aTarget,
+                           WidgetKeyboardEvent& aEvent,
+                           nsEventStatus& aStatus);
+
+  // This method will be called after dispatching keypress to its target,
+  // if the input-method-app doesn't handle the key.
+  // In normal dispatching path, EventStateManager::PostHandleKeyboardEvent
+  // will be called when event is keypress.
+  // However, the ::PostHandleKeyboardEvent mentioned above will be aborted
+  // when we try to forward key event to the input-method-app.
+  // If the input-method-app consumes the key, then we don't need to do anything
+  // because the input-method-app will generate a new key event by itself.
+  // On the other hand, if the input-method-app doesn't consume the key,
+  // then we need to dispatch the key event by ourselves
+  // and call ::PostHandleKeyboardEvent again after the event is forwarded.
+  // Note that the EventStateManager::PreHandleEvent is already called before
+  // forwarding, so we don't need to call it in this module.
+  void PostHandleKeyboardEvent(nsINode* aTarget,
+                               WidgetKeyboardEvent& aEvent,
+                               nsEventStatus& aStatus);
+
+  void SetDefaultPrevented(WidgetKeyboardEvent& aEvent,
+                           uint16_t aDefaultPrevented);
+
+  // Check whether the event is valid to be fired.
+  // This method should be called every time before dispatching next event.
+  bool CanDispatchEvent(nsINode* aTarget,
+                        WidgetKeyboardEvent& aEvent);
+
+  already_AddRefed<nsPIDOMWindowOuter> GetRootWindow(nsINode* aNode);
+
+  already_AddRefed<nsIContent> GetCurrentTarget();
+
+  nsPresContext* GetPresContext(nsINode* aNode);
+
+  already_AddRefed<nsIPresShell> GetPresShell(nsINode* aNode);
+
+  static StaticRefPtr<HardwareKeyHandler> sInstance;
+
+  // The event queue is used to store the forwarded keyboard events.
+  // Those stored events will be dispatched if input-method-app doesn't
+  // consume them.
+  EventQueue<KeyboardInfo> mEventQueue;
+
+  // Hold the pointer to the latest keydown's data
+  RefPtr<KeyboardInfo> mLatestKeyDownInfo;
+
+  // input-method-app needs to register a listener by
+  // |nsIHardwareKeyHandler.registerListener| to receive
+  // the hardware keyboard event, and |nsIHardwareKeyHandler.registerListener|
+  // will set an nsIHardwareKeyEventListener to mHardwareKeyEventListener.
+  // Then, mHardwareKeyEventListener is used to forward the event
+  // to the input-method-app.
+  nsWeakPtr mHardwareKeyEventListener;
+
+  // To keep tracking the input-method-app is active or disabled.
+  bool mInputMethodAppConnected;
+};
+
+} // namespace mozilla
+
+#endif // #ifndef mozilla_HardwareKeyHandler_h_