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

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

#include "modules/accessibility/AXARIAGridRow.h"
#include "modules/accessibility/AXObjectCacheImpl.h"
#include "modules/accessibility/AXTableColumn.h"

namespace blink {

AXARIAGrid::AXARIAGrid(LayoutObject* layout_object,
                       AXObjectCacheImpl& ax_object_cache)
    : AXTable(layout_object, ax_object_cache) {}

AXARIAGrid::~AXARIAGrid() = default;

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

bool AXARIAGrid::AddRow(AXObject* possible_row) {
  // This does not yet handle the case where the row is not an AXARIAGridRow or
  // AXTable row because it is in a canvas or is a virtual node, as those
  // do not have a layout object, cannot be an AXARIAGridRow, and cannot
  // currently implement the rest of our table logic.
  if (!possible_row || !possible_row->IsTableRow())
    return false;

  AXTableRow* row = ToAXTableRow(possible_row);
  row->SetRowIndex(static_cast<int>(rows_.size()));
  rows_.push_back(possible_row);
  return true;
}

void AXARIAGrid::ComputeRows(AXObjectVector possible_rows) {
  // Only add children that are actually rows.
  for (const auto& possible_row : possible_rows) {
    if (!AddRow(possible_row)) {
      // Normally with good authoring practices, the rows should be children of
      // the grid. However, if this is not the case, recursively look for rows
      // in the descendants of the non-row child.
      if (!possible_row->HasChildren())
        possible_row->AddChildren();

      ComputeRows(possible_row->Children());
    }
  }
}

unsigned AXARIAGrid::CalculateNumColumns() {
  unsigned num_cols = 0;
  for (const auto& row : rows_) {
    // Store the maximum number of columns.
    DCHECK(row->IsTableRow());
    const unsigned num_cells_in_row = ToAXTableRow(row)->Cells().size();
    if (num_cells_in_row > num_cols)
      num_cols = num_cells_in_row;
  }
  return num_cols;
}

void AXARIAGrid::AddColumnChildren(unsigned num_cols) {
  AXObjectCacheImpl& ax_cache = AXObjectCache();
  for (unsigned i = 0; i < num_cols; ++i) {
    AXTableColumn* column = ToAXTableColumn(ax_cache.GetOrCreate(kColumnRole));
    column->SetColumnIndex((int)i);
    column->SetParent(this);
    columns_.push_back(column);
    if (!column->AccessibilityIsIgnored())  // TODO is this check necessary?
      children_.push_back(column);
  }
}

void AXARIAGrid::AddHeaderContainerChild() {
  AXObject* header_container_object = HeaderContainer();
  if (header_container_object &&
      !header_container_object->AccessibilityIsIgnored())
    children_.push_back(header_container_object);
}

void AXARIAGrid::AddChildren() {
  DCHECK(!IsDetached());
  DCHECK(!have_children_);

  AXLayoutObject::AddChildren();

  if (IsAXTable() && layout_object_) {
    ComputeRows(children_);
    AddColumnChildren(CalculateNumColumns());
    AddHeaderContainerChild();
  }
}

}  // namespace blink