a11y uia: Bridge QAccessibleAttributesInterface to UIA

This bridges the 2 currently existing attribute types for
the newly added QAccessibleAttributesInterface to UIA.

As described in the AT-SPI bridge implementation already,
QAccessible::Attribute::Level semantically matches
the "aria-level" ARIA attribute, and is mapped to
a "level" property for the UIA_AriaPropertiesPropertyId
as described in the Core Accessibility API Mappings
specification for both, headings [1] and non-headings [2].

Map all attributes set in QAccessible::Attribute::Custom
to that property as well, keeping key and value as they
are.

As described in the UIA Element Properties Identifiers
doc [3] for UIA_AriaPropertiesPropertyId:

> AriaProperties is a collection of Name/Value pairs with
> delimiters of = (equals) and ; (semicolon), for example,
> "checked=true;disabled=false".

In addition, if the level attribute is set for an object
of role heading, report the corresponding
StyleId_Heading for UIA_StyleIdAttributeId, as also
described in the Core Accessibility API Mappings spec [1].

For MingW, add UIA_StyleIdAttributeId and
StyleId_Heading<NUMBER> defines
to qwindowsuiautomation.h, as the MingW headers
apparently don't have them yet (see log of
failed MingW builds without those defines: [4] [5]).

[1] https://www.w3.org/TR/core-aam-1.2/#ariaLevelHeading
[2] https://www.w3.org/TR/core-aam-1.2/#ariaLevel
[3] https://learn.microsoft.com/en-us/windows/win32/winauto/uiauto-automation-element-propids
[4] 051e46739b/build_1716364832/log.txt.gz
[5] b8e6241678/build_1716370445/log.txt.gz

Fixes: QTBUG-119057
Change-Id: I00b15e95c35c0f31ba34161bc061a3085fc28682
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

src/plugins/platforms/windows/uiautomation/qwindowsuiamainprovider.cpp

@@ -388,6 +388,93 @@ void QWindowsUiaMainProvider::fillVariantArrayForRelation(QAccessibleInterface*
     pRetVal->parray = elements;
 }
 
+void QWindowsUiaMainProvider::setAriaProperties(QAccessibleInterface *accessible, VARIANT *pRetVal)
+{
+    Q_ASSERT(accessible);
+
+    QAccessibleAttributesInterface *attributesIface = accessible->attributesInterface();
+    if (!attributesIface)
+        return;
+
+    QString ariaString;
+    const QList<QAccessible::Attribute> attrKeys = attributesIface->attributeKeys();
+    for (qsizetype i = 0; i < attrKeys.size(); ++i) {
+        if (i != 0)
+            ariaString += QStringLiteral(";");
+        const QAccessible::Attribute key = attrKeys.at(i);
+        const QVariant value = attributesIface->attributeValue(key);
+        // see "Core Accessibility API Mappings" spec: https://www.w3.org/TR/core-aam-1.2/
+        switch (key) {
+        case QAccessible::Attribute::Custom:
+        {
+            // forward custom attributes as-is
+            Q_ASSERT((value.canConvert<QHash<QString, QString>>()));
+            const QHash<QString, QString> attrMap = value.value<QHash<QString, QString>>();
+            for (auto [name, val] : attrMap.asKeyValueRange()) {
+                if (name != *attrMap.keyBegin())
+                    ariaString += QStringLiteral(";");
+                ariaString += name + QStringLiteral("=") + val;
+            }
+            break;
+        }
+        case QAccessible::Attribute::Level:
+            Q_ASSERT(value.canConvert<int>());
+            ariaString += QStringLiteral("level=") + QString::number(value.toInt());
+            break;
+        default:
+            break;
+        }
+    }
+
+    setVariantString(ariaString, pRetVal);
+}
+
+void QWindowsUiaMainProvider::setStyle(QAccessibleInterface *accessible, VARIANT *pRetVal)
+{
+    Q_ASSERT(accessible);
+
+    QAccessibleAttributesInterface *attributesIface = accessible->attributesInterface();
+    if (!attributesIface)
+        return;
+
+    // currently, only heading styles are implemented here
+    if (accessible->role() != QAccessible::Role::Heading)
+        return;
+
+    const QVariant levelVariant = attributesIface->attributeValue(QAccessible::Attribute::Level);
+    if (!levelVariant.isValid())
+        return;
+
+    Q_ASSERT(levelVariant.canConvert<int>());
+    // UIA only has styles for heading levels 1-9
+    const int level = levelVariant.toInt();
+    if (level < 1 || level > 9)
+        return;
+
+    const int styleId = styleIdForHeadingLevel(level);
+    setVariantI4(styleId, pRetVal);
+}
+
+int QWindowsUiaMainProvider::styleIdForHeadingLevel(int headingLevel)
+{
+    // only heading levels 1-9 have a corresponding UIA style ID
+    Q_ASSERT(headingLevel > 0 && headingLevel <= 9);
+
+    static constexpr int styles[] = {
+        StyleId_Heading1,
+        StyleId_Heading2,
+        StyleId_Heading3,
+        StyleId_Heading4,
+        StyleId_Heading5,
+        StyleId_Heading6,
+        StyleId_Heading7,
+        StyleId_Heading8,
+        StyleId_Heading9,
+    };
+
+    return styles[headingLevel - 1];
+}
+
 HRESULT QWindowsUiaMainProvider::GetPropertyValue(PROPERTYID idProp, VARIANT *pRetVal)
 {
     qCDebug(lcQpaUiAutomation) << __FUNCTION__ << idProp;
@@ -411,6 +498,9 @@ HRESULT QWindowsUiaMainProvider::GetPropertyValue(PROPERTYID idProp, VARIANT *pR
         // Accelerator key.
         setVariantString(accessible->text(QAccessible::Accelerator), pRetVal);
         break;
+    case UIA_AriaPropertiesPropertyId:
+        setAriaProperties(accessible, pRetVal);
+        break;
     case UIA_AutomationIdPropertyId:
         // Automation ID, which can be used by tools to select a specific control in the UI.
         setVariantString(automationIdForAccessible(accessible), pRetVal);
@@ -511,6 +601,9 @@ HRESULT QWindowsUiaMainProvider::GetPropertyValue(PROPERTYID idProp, VARIANT *pR
         setVariantString(name, pRetVal);
         break;
     }
+    case UIA_StyleIdAttributeId:
+        setStyle(accessible, pRetVal);
+        break;
     default:
         break;
     }

src/plugins/platforms/windows/uiautomation/qwindowsuiamainprovider.h

@@ -61,6 +61,10 @@ public:
 private:
     QString automationIdForAccessible(const QAccessibleInterface *accessible);
     static void fillVariantArrayForRelation(QAccessibleInterface *accessible, QAccessible::Relation relation, VARIANT *pRetVal);
+    static void setAriaProperties(QAccessibleInterface *accessible, VARIANT *pRetVal);
+    static void setStyle(QAccessibleInterface *accessible, VARIANT *pRetVal);
+    /** Returns the UIA style ID for a heading level from 1 to 9. */
+    static int styleIdForHeadingLevel(int headingLevel);
     static QMutex m_mutex;
 };
 

src/plugins/platforms/windows/uiautomation/qwindowsuiautomation.h

@@ -14,8 +14,19 @@
 #define UIA_SelectionPattern2Id                  10034
 #define UIA_IsReadOnlyAttributeId                40015
 #define UIA_StrikethroughStyleAttributeId        40026
+#define UIA_StyleIdAttributeId                   40034
 #define UIA_CaretPositionAttributeId             40038
 
+#define StyleId_Heading1    70001
+#define StyleId_Heading2    70002
+#define StyleId_Heading3    70003
+#define StyleId_Heading4    70004
+#define StyleId_Heading5    70005
+#define StyleId_Heading6    70006
+#define StyleId_Heading7    70007
+#define StyleId_Heading8    70008
+#define StyleId_Heading9    70009
+
 enum CaretPosition {
     CaretPosition_Unknown           = 0,
     CaretPosition_EndOfLine         = 1,