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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:expandtab:shiftwidth=2:tabstop=2:
*/
/* 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
#ifndef mozilla_a11y_aria_ARIAMap_h_
#define mozilla_a11y_aria_ARIAMap_h_
#include "ARIAStateMap.h"
#include "mozilla/a11y/AccTypes.h"
#include "mozilla/a11y/Role.h"
#include "nsAtom.h"
#include "nsIContent.h"
#include "nsTHashSet.h"
class nsINode;
namespace mozilla::dom {
class Element;
}
////////////////////////////////////////////////////////////////////////////////
// Value constants
/**
* Used to define if role requires to expose Value interface.
*/
enum EValueRule {
/**
* Value interface isn't exposed.
*/
eNoValue,
/**
* Value interface is implemented, supports value, min and max from
* aria-valuenow, aria-valuemin and aria-valuemax.
*/
eHasValueMinMax,
/**
* Value interface is implemented, but only if the element is focusable.
* For instance, in ARIA 1.1 the ability for authors to create adjustable
* splitters was provided by supporting the value interface on separators
* that are focusable. Non-focusable separators expose no value information.
*/
eHasValueMinMaxIfFocusable
};
////////////////////////////////////////////////////////////////////////////////
// Action constants
/**
* Used to define if the role requires to expose action.
*/
enum EActionRule {
eNoAction,
eActivateAction,
eClickAction,
ePressAction,
eCheckUncheckAction,
eExpandAction,
eJumpAction,
eOpenCloseAction,
eSelectAction,
eSortAction,
eSwitchAction
};
////////////////////////////////////////////////////////////////////////////////
// Live region constants
/**
* Used to define if role exposes default value of aria-live attribute.
*/
enum ELiveAttrRule {
eNoLiveAttr,
eOffLiveAttr,
ePoliteLiveAttr,
eAssertiveLiveAttr
};
////////////////////////////////////////////////////////////////////////////////
// Role constants
/**
* ARIA role overrides role from native markup.
*/
const bool kUseMapRole = true;
/**
* ARIA role doesn't override the role from native markup.
*/
const bool kUseNativeRole = false;
////////////////////////////////////////////////////////////////////////////////
// ARIA attribute characteristic masks
/**
* This mask indicates the attribute should not be exposed as an object
* attribute via the catch-all logic in Accessible::Attributes().
* This means it either isn't mean't to be exposed as an object attribute, or
* that it should, but is already handled in other code.
*/
const uint8_t ATTR_BYPASSOBJ = 0x1 << 0;
const uint8_t ATTR_BYPASSOBJ_IF_FALSE = 0x1 << 1;
/**
* This mask indicates the attribute is expected to have an NMTOKEN or bool
* value. (See for example usage in Accessible::Attributes())
*/
const uint8_t ATTR_VALTOKEN = 0x1 << 2;
/**
* Indicate the attribute is global state or property (refer to
*/
const uint8_t ATTR_GLOBAL = 0x1 << 3;
/**
* Indicates that the attribute should have an integer value.
*/
const uint8_t ATTR_VALINT = 0x1 << 4;
////////////////////////////////////////////////////////////////////////////////
// State map entry
/**
* Used in nsRoleMapEntry.state if no nsIAccessibleStates are automatic for
* a given role.
*/
#define kNoReqStates 0
////////////////////////////////////////////////////////////////////////////////
// Role map entry
/**
* For each ARIA role, this maps the nsIAccessible information.
*/
struct nsRoleMapEntry {
/**
* Return true if matches to the given ARIA role.
*/
bool Is(nsAtom* aARIARole) const { return roleAtom == aARIARole; }
/**
* Return true if ARIA role has the given accessible type.
*/
bool IsOfType(mozilla::a11y::AccGenericType aType) const {
return accTypes & aType;
}
/**
* Return ARIA role.
*/
const nsDependentAtomString ARIARoleString() const {
return nsDependentAtomString(roleAtom);
}
// ARIA role: string representation such as "button"
nsStaticAtom* const roleAtom;
// Role mapping rule: maps to enum Role
mozilla::a11y::role role;
// Role rule: whether to use mapped role or native semantics
bool roleRule;
// Value mapping rule: how to compute accessible value
EValueRule valueRule;
// Action mapping rule, how to expose accessible action
EActionRule actionRule;
// 'live' and 'container-live' object attributes mapping rule: how to expose
// these object attributes if ARIA 'live' attribute is missed.
ELiveAttrRule liveAttRule;
// LocalAccessible types this role belongs to.
uint32_t accTypes;
// Automatic state mapping rule: always include in states
uint64_t state; // or kNoReqStates if no default state for this role
// ARIA properties supported for this role (in other words, the aria-foo
// attribute to accessible states mapping rules).
// Currently you cannot have unlimited mappings, because
// a variable sized array would not allow the use of
// C++'s struct initialization feature.
mozilla::a11y::aria::EStateRule attributeMap1;
mozilla::a11y::aria::EStateRule attributeMap2;
mozilla::a11y::aria::EStateRule attributeMap3;
mozilla::a11y::aria::EStateRule attributeMap4;
};
////////////////////////////////////////////////////////////////////////////////
// ARIA map
/**
* These provide the mappings for WAI-ARIA roles, states and properties using
* the structs defined in this file and ARIAStateMap files.
*/
namespace mozilla {
namespace a11y {
class AccAttributes;
namespace aria {
/**
* Empty role map entry. Used by accessibility service to create an accessible
* if the accessible can't use role of used accessible class. For example,
* it is used for table cells that aren't contained by table.
*/
extern nsRoleMapEntry gEmptyRoleMap;
/**
* Constants for the role map entry index to indicate that the role map entry
* isn't in sWAIRoleMaps, but rather is a special entry: nullptr,
* gEmptyRoleMap, and sLandmarkRoleMap
*/
const uint8_t NO_ROLE_MAP_ENTRY_INDEX = UINT8_MAX - 2;
const uint8_t EMPTY_ROLE_MAP_ENTRY_INDEX = UINT8_MAX - 1;
const uint8_t LANDMARK_ROLE_MAP_ENTRY_INDEX = UINT8_MAX;
/**
* Get the role map entry for a given DOM node. This will use the first
* ARIA role if the role attribute provides a space delimited list of roles.
*
* @param aEl [in] the DOM node to get the role map entry for
* @return a pointer to the role map entry for the ARIA role, or nullptr
* if none
*/
const nsRoleMapEntry* GetRoleMap(dom::Element* aEl);
/*
* Get the role map entry pointer's index for a given DOM node, skipping any
* given roles. This will use the first valid ARIA role if the role attribute
* provides a space delimited list of roles, excluding any given roles.
*
* @param aEl [in] the DOM node to get the role map entry for
* @param aRolesToSkip [in] the roles to skip when searching the role string
* @return the index of the pointer to the role map entry for the
* ARIA role, or NO_ROLE_MAP_ENTRY_INDEX if none
*/
uint8_t GetFirstValidRoleMapIndexExcluding(
dom::Element* aEl, std::initializer_list<nsStaticAtom*> aRolesToSkip);
/**
* Get the role map entry pointer's index for a given DOM node. This will use
* the first ARIA role if the role attribute provides a space delimited list of
* roles.
*
* @param aEl [in] the DOM node to get the role map entry for
* @return the index of the pointer to the role map entry for the ARIA
* role, or NO_ROLE_MAP_ENTRY_INDEX if none
*/
uint8_t GetRoleMapIndex(dom::Element* aEl);
/**
* Get the role map entry pointer for a given role map entry index.
*
* @param aRoleMapIndex [in] the role map index to get the role map entry
* pointer for
* @return a pointer to the role map entry for the ARIA role,
* or nullptr, if none
*/
const nsRoleMapEntry* GetRoleMapFromIndex(uint8_t aRoleMapIndex);
/**
* Get the role map entry index for a given role map entry pointer. If the role
* map entry is within sWAIRoleMaps, return the index within that array,
* otherwise return one of the special index constants listed above.
*
* @param aRoleMap [in] the role map entry pointer to get the index for
* @return the index of the pointer to the role map entry, or
* NO_ROLE_MAP_ENTRY_INDEX if none
*/
uint8_t GetIndexFromRoleMap(const nsRoleMapEntry* aRoleMap);
/**
* Determine whether a role map entry index is valid.
*/
bool IsRoleMapIndexValid(uint8_t aRoleMapIndex);
/**
* Return accessible state from ARIA universal states applied to the given
* element.
*/
uint64_t UniversalStatesFor(dom::Element* aElement);
/**
* Get the ARIA attribute characteristics for a given ARIA attribute.
*
* @param aAtom ARIA attribute
* @return A bitflag representing the attribute characteristics
* (see above for possible bit masks, prefixed "ATTR_")
*/
uint8_t AttrCharacteristicsFor(nsAtom* aAtom);
/**
* Return true if the element has defined aria-hidden.
*/
bool HasDefinedARIAHidden(nsIContent* aContent);
/**
* Represents a simple enumerator for iterating through ARIA attributes
* exposed as object attributes on a given accessible.
*/
class AttrIterator {
public:
explicit AttrIterator(nsIContent* aContent);
bool Next();
nsAtom* AttrName() const;
void AttrValue(nsAString& aAttrValue) const;
/**
* Expose this ARIA attribute in a specified AccAttributes. The appropriate
* type will be used for the attribute; e.g. an atom for a token value.
*/
bool ExposeAttr(AccAttributes* aTargetAttrs) const;
private:
AttrIterator() = delete;
AttrIterator(const AttrIterator&) = delete;
AttrIterator& operator=(const AttrIterator&) = delete;
dom::Element* mElement;
bool mIteratingDefaults;
nsTHashSet<RefPtr<nsAtom>> mOverriddenAttrs;
const AttrArray* mAttrs;
uint32_t mAttrIdx;
uint32_t mAttrCount;
RefPtr<nsAtom> mAttrAtom;
uint8_t mAttrCharacteristics;
};
} // namespace aria
} // namespace a11y
} // namespace mozilla
#endif