blob: 8d933615b7c987efd92521647533528c5bbbc5c0 [file] [log] [blame]
// Copyright 2020 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 <string>
#include "third_party/blink/renderer/core/core_export.h"
#include "third_party/blink/renderer/core/editing/commands/edit_command.h"
#include "third_party/blink/renderer/core/editing/selection_modifier.h"
#include "third_party/blink/renderer/core/editing/set_selection_options.h"
#include "third_party/blink/renderer/core/editing/text_granularity.h"
#include "third_party/blink/renderer/core/editing/visible_units.h"
#include "third_party/blink/renderer/platform/text/text_direction.h"
#include "third_party/blink/renderer/platform/wtf/hash_table_deleted_value_type.h"
#include "third_party/blink/renderer/platform/wtf/hash_traits.h"
#include "ui/accessibility/ax_enums.mojom-blink-forward.h"
#include "ui/accessibility/ax_event.h"
#include "ui/accessibility/ax_event_intent.h"
namespace blink {
// Adapts a ui::AXEventIntent for use in a Blink HashCountedSet.
// An event intent describes what caused an accessibility event to be raised.
// For example, a character could have been typed, a word replaced, or a line
// deleted. Or, the selection could have been extended to the beginning of the
// previous word, or it could have been moved to the end of the next line.
class CORE_EXPORT BlinkAXEventIntent final {
static BlinkAXEventIntent FromEditCommand(const EditCommand& edit_command);
static BlinkAXEventIntent FromClearedSelection(
const SetSelectionBy set_selection_by);
static BlinkAXEventIntent FromModifiedSelection(
const SelectionModifyAlteration alter,
const SelectionModifyDirection direction,
const TextGranularity granularity,
const SetSelectionBy set_selection_by,
const TextDirection direction_of_selection,
const PlatformWordBehavior platform_word_behavior);
static BlinkAXEventIntent FromNewSelection(
const TextGranularity granularity,
bool is_base_first,
const SetSelectionBy set_selection_by);
// Creates an empty (uninitialized) instance.
// Constructs an event intent which contains only a command without any other
// arguments. This is used e.g. by the selection changed event when the
// current selection is cleared.
explicit BlinkAXEventIntent(ax::mojom::blink::Command command);
// Constructs an editing event intent; which is primarily attached to a text
// changed or a text attributes changed event.
BlinkAXEventIntent(ax::mojom::blink::Command command,
ax::mojom::blink::InputEventType input_event_type);
// Constructs a selection event intent; which is attached to a selection
// changed event.
BlinkAXEventIntent(ax::mojom::blink::Command command,
ax::mojom::blink::TextBoundary text_boundary,
ax::mojom::blink::MoveDirection move_direction);
// Used by HashCountedSet to create a deleted BlinkAXEventIntent instance.
explicit BlinkAXEventIntent(WTF::HashTableDeletedValueType type);
virtual ~BlinkAXEventIntent();
BlinkAXEventIntent(const BlinkAXEventIntent& intent);
BlinkAXEventIntent& operator=(const BlinkAXEventIntent& intent);
CORE_EXPORT friend bool operator==(const BlinkAXEventIntent& a,
const BlinkAXEventIntent& b);
CORE_EXPORT friend bool operator!=(const BlinkAXEventIntent& a,
const BlinkAXEventIntent& b);
const ui::AXEventIntent& intent() const { return intent_; }
ui::AXEventIntent& intent() { return intent_; }
// Returns "true" if this represents an initialized BlinkAXEventIntent
// instance.
bool is_initialized() const { return is_initialized_; }
// Returns "true" if this represents a deleted BlinkAXEventIntent instance.
bool IsHashTableDeletedValue() const;
// Returns a string representation of this instance.
std::string ToString() const;
ui::AXEventIntent intent_;
// Set to "true" if this represents an initialized BlinkAXEventIntent
// instance. An empty (uninitialized) instance is created either by calling
// the default constructor or by simply zeroing out a block of memory
// equivalent to the size of this class. The latter may be done by the HashSet
// for performance reasons.
// This member is needed so that our hash function will never return the same
// value for an uninitialized and an initialized instance. Otherwise an
// uninitialized instance's memory may have random values.
bool is_initialized_ = false;
// Set to "true" if this represents a deleted BlinkAXEventIntent instance.
bool is_deleted_ = false;
struct CORE_EXPORT BlinkAXEventIntentHash final {
// Computes the hash of a BlinkAXEventIntent instance.
static unsigned GetHash(const BlinkAXEventIntent& key);
// Used by HashSet to compare two BlinkAXEventIntent instances.
static bool Equal(const BlinkAXEventIntent& a, const BlinkAXEventIntent& b);
// We support creating and comparing with empty (uninitialized) and deleted
// HashSet BlinkAXEventIntent entries.
static constexpr bool safe_to_compare_to_empty_or_deleted = true;
struct CORE_EXPORT BlinkAXEventIntentHashTraits final
: WTF::SimpleClassHashTraits<BlinkAXEventIntent> {
// Zeroed memory cannot be used for BlinkAXEventIntent.
static constexpr bool kEmptyValueIsZero = false;
} // namespace blink