third_party/WebKit/Source/modules/accessibility/AXARIAGridCell.cpp

/*
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#include "modules/accessibility/AXARIAGridCell.h"

#include "modules/accessibility/AXObjectCacheImpl.h"
#include "modules/accessibility/AXTable.h"
#include "modules/accessibility/AXTableRow.h"

namespace blink {

AXARIAGridCell::AXARIAGridCell(LayoutObject* layout_object,
                               AXObjectCacheImpl& ax_object_cache)
    : AXTableCell(layout_object, ax_object_cache) {}

AXARIAGridCell::~AXARIAGridCell() {}

AXARIAGridCell* AXARIAGridCell::Create(LayoutObject* layout_object,
                                       AXObjectCacheImpl& ax_object_cache) {
  return new AXARIAGridCell(layout_object, ax_object_cache);
}

bool AXARIAGridCell::IsAriaColumnHeader() const {
  const AtomicString& role = GetAttribute(HTMLNames::roleAttr);
  return EqualIgnoringASCIICase(role, "columnheader");
}

bool AXARIAGridCell::IsAriaRowHeader() const {
  const AtomicString& role = GetAttribute(HTMLNames::roleAttr);
  return EqualIgnoringASCIICase(role, "rowheader");
}

AXObject* AXARIAGridCell::ParentTable() const {
  AXObject* ancestor =
      static_cast<AXObject*>(const_cast<AXARIAGridCell*>(this));
  do {
    ancestor = ancestor->ParentObjectUnignored();
  } while (ancestor && !ancestor->IsAXTable());
  return ancestor;
}

AXObject* AXARIAGridCell::ParentRow() const {
  AXObject* ancestor =
      static_cast<AXObject*>(const_cast<AXARIAGridCell*>(this));
  do {
    ancestor = ancestor->ParentObjectUnignored();
  } while (ancestor && !ancestor->IsTableRow());
  return ancestor;
}

bool AXARIAGridCell::RowIndexRange(
    std::pair<unsigned, unsigned>& row_range) const {
  AXObject* parent = ParentObjectUnignored();
  if (!parent)
    return false;

  // Use native table semantics if this is ARIA overlayed on an HTML table.
  if (AXTableCell::RowIndexRange(row_range))
    return true;

  AXObject* row = ParentRow();
  if (row && row->IsTableRow()) {
    // We already got a table row, use its API.
    row_range.first = ToAXTableRow(row)->RowIndex();
  } else if (parent->IsAXTable()) {
    // We reached the parent table, so we need to inspect its
    // children to determine the row index for the cell in it.
    // TODO do we still want this?
    unsigned column_count = ToAXTable(parent)->ColumnCount();
    if (!column_count)
      return false;

    const auto& siblings = parent->Children();
    unsigned children_size = siblings.size();
    for (unsigned k = 0; k < children_size; ++k) {
      if (siblings[k].Get() == this) {
        row_range.first = k / column_count;
        break;
      }
    }
  }

  // ARIA cells not based on th/td can have an aria-rowspan, however that is not
  // exposed here as this method only exposes physical coordinates, not virtual.
  row_range.second = 1;
  return true;
}

bool AXARIAGridCell::ColumnIndexRange(
    std::pair<unsigned, unsigned>& column_range) const {
  // Use native table semantics if this is ARIA overlayed on an HTML table.
  if (AXTableCell::ColumnIndexRange(column_range))
    return true;

  AXObject* row = ParentRow();
  if (!row)
    return false;  // Auto col index range not supported if no row object

  DCHECK(row->IsTableRow());
  const auto& cells = ToAXTableRow(row)->Cells();
  unsigned cells_size = cells.size();
  for (unsigned k = 0; k < cells_size; ++k) {
    if (cells[k].Get() == this) {
      column_range.first = k;
      break;
    }
  }

  // ARIA cells not based on th/td can have an aria-colspan, however that is not
  // exposed here as this method only exposes physical coordinates, not virtual.
  column_range.second = 1;
  return true;
}

AccessibilityRole AXARIAGridCell::ScanToDecideHeaderRole() {
  if (IsAriaRowHeader())
    return kRowHeaderRole;

  if (IsAriaColumnHeader())
    return kColumnHeaderRole;

  return AXTableCell::ScanToDecideHeaderRole();
}

AXRestriction AXARIAGridCell::Restriction() const {
  const AXRestriction cell_restriction = AXLayoutObject::Restriction();
  // Specified gridcell restriction or local ARIA markup takes precedence.
  if (cell_restriction != kNone || HasAttribute(HTMLNames::aria_readonlyAttr) ||
      HasAttribute(HTMLNames::aria_disabledAttr))
    return cell_restriction;

  // Gridcell does not have it's own ARIA input restriction, so
  // fall back on parent grid's readonly state.
  // See ARIA specification regarding grid/treegrid and readonly.
  const AXObject* container = ParentTable();
  const bool is_in_readonly_grid = container &&
                                   (container->RoleValue() == kGridRole ||
                                    container->RoleValue() == kTreeGridRole) &&
                                   container->Restriction() == kReadOnly;
  return is_in_readonly_grid ? kReadOnly : kNone;
}

}  // namespace blink