// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef CONTENT_BROWSER_RENDERER_HOST_TEXT_INPUT_CLIENT_MAC_H_
#define CONTENT_BROWSER_RENDERER_HOST_TEXT_INPUT_CLIENT_MAC_H_
#include "base/functional/callback.h"
#include "base/gtest_prod_util.h"
#include "base/synchronization/condition_variable.h"
#include "base/synchronization/lock.h"
#include "base/time/time.h"
#include "content/common/content_export.h"
#include "ui/base/mojom/attributed_string.mojom-forward.h"
#include "ui/gfx/geometry/point.h"
#include "ui/gfx/geometry/rect.h"
namespace base {
template <typename T>
struct DefaultSingletonTraits;
} // namespace base
namespace gfx {
class Range;
}
namespace content {
class RenderWidgetHost;
// This class helps with the macOS dictionary popup. For the design overview,
// look at this document:
// http://dev.chromium.org/developers/design-documents/system-dictionary-pop-up-architecture
//
// This service is used to marshall information for these three methods that are
// implemented in RenderWidgetHostViewMac:
// -[NSTextInput characterIndexForPoint:]
// -[NSTextInput attributedSubstringFromRange:]
// -[NSTextInput firstRectForCharacterRange:]
//
// Because these methods are part of a synchronous system API, implementing them
// requires getting information from the renderer synchronously. Rather than
// using an actual sync IPC message, a normal async ViewMsg is used with a lock
// and condition (managed by this service).
//
// Mac OS 10.8 introduced -[NSResponder quickLookWithEvent:].
// We can use it to implement asynchronous dictionary lookup when the user
// taps a word using three fingers.
// But currently the "Look Up in Dictionary" context menu item still goes
// through the above synchronous IPC.
class CONTENT_EXPORT TextInputClientMac {
public:
// Returns the singleton instance.
static TextInputClientMac* GetInstance();
TextInputClientMac(const TextInputClientMac&) = delete;
TextInputClientMac& operator=(const TextInputClientMac&) = delete;
// Each of the three methods mentioned above has an associated pair of methods
// to get data from the renderer. The Get*() methods block the calling thread
// (always the UI thread) with a short timeout after the async message has
// been sent to the renderer to lookup the information needed to respond to
// the system. The Set*AndSignal() methods store the looked up information in
// this service and signal the condition to allow the Get*() methods to
// unlock and return that stored value.
//
// Returns UINT32_MAX if the request times out or is not completed.
uint32_t GetCharacterIndexAtPoint(RenderWidgetHost* rwh,
const gfx::Point& point);
// Returns NSZeroRect if the request times out or is not completed. The result
// is in WebKit coordinates.
gfx::Rect GetFirstRectForRange(RenderWidgetHost* rwh,
const gfx::Range& range);
// When the renderer sends the ViewHostMsg reply, the RenderMessageFilter will
// call the corresponding method on the IO thread to unlock the condition and
// allow the Get*() methods to continue/return.
void SetCharacterIndexAndSignal(uint32_t index);
void SetFirstRectAndSignal(const gfx::Rect& first_rect);
typedef base::OnceCallback<void(ui::mojom::AttributedStringPtr,
const gfx::Point&)>
GetStringCallback;
// This async method is invoked from RenderWidgetHostViewCocoa's
// -quickLookWithEvent:, when the user taps a word using 3 fingers.
// The reply callback will be invoked from the IO thread; the caller is
// responsible for bouncing to the main thread if necessary.
// The callback parameters provide the attributed word under the point and
// the lower left baseline point of the text.
void GetStringAtPoint(RenderWidgetHost* rwh,
const gfx::Point& point,
GetStringCallback callback);
// This async method is invoked when browser tries to retreive the text for
// certain range and doesn't want to wait for the reply from blink.
// The reply callback will be invoked from the IO thread; the caller is
// responsible for bouncing to the main thread if necessary.
// The callback parameters provide the attributed word under the point and
// the lower left baseline point of the text.
void GetStringFromRange(RenderWidgetHost* rwh,
const gfx::Range& range,
GetStringCallback callback);
private:
friend struct base::DefaultSingletonTraits<TextInputClientMac>;
FRIEND_TEST_ALL_PREFIXES(TextInputClientMacTest, TimeoutRectForRange);
TextInputClientMac();
~TextInputClientMac();
// The critical sections that the Condition guards are in Get*() methods.
// These methods lock the internal condition for use before the asynchronous
// message is sent to the renderer to lookup the required information. These
// are only used on the UI thread.
void BeforeRequest() EXCLUSIVE_LOCK_FUNCTION(lock_);
// Called at the end of a critical section. This will release the lock and
// condition.
void AfterRequest() UNLOCK_FUNCTION(lock_);
uint32_t character_index_;
gfx::Rect first_rect_;
base::Lock lock_;
base::ConditionVariable condition_;
// The amount of time that the browser process will wait for a response from
// the renderer.
base::TimeDelta wait_timeout_;
};
} // namespace content
#endif // CONTENT_BROWSER_RENDERER_HOST_TEXT_INPUT_CLIENT_MAC_H_