

#include "core/html/HTMLTableRowsCollection.h"

#include "core/HTMLNames.h"
#include "core/dom/ElementTraversal.h"
#include "core/html/HTMLTableElement.h"
#include "core/html/HTMLTableRowElement.h"

namespace blink {

using namespace HTMLNames;

static inline bool isInSection(HTMLTableRowElement& row, const HTMLQualifiedName& sectionTag)
{
    // Because we know that the parent is a table or a section, it's safe to cast it to an HTMLElement
    // giving us access to the faster hasTagName overload from that class.
    return toHTMLElement(row.parentNode())->hasTagName(sectionTag);
}

HTMLTableRowElement* HTMLTableRowsCollection::rowAfter(HTMLTableElement& table, HTMLTableRowElement* previous)
{
    // Start by looking for the next row in this section.
    // Continue only if there is none.
    if (previous && previous->parentNode() != table) {
        if (HTMLTableRowElement* row = Traversal<HTMLTableRowElement>::nextSibling(*previous))
            return row;
    }

    // If still looking at head sections, find the first row in the next head section.
    HTMLElement* child = 0;
    if (!previous)
        child = Traversal<HTMLElement>::firstChild(table);
    else if (isInSection(*previous, theadTag))
        child = Traversal<HTMLElement>::nextSibling(*previous->parentNode());
    for (; child; child = Traversal<HTMLElement>::nextSibling(*child)) {
        if (child->hasTagName(theadTag)) {
            if (HTMLTableRowElement* row = Traversal<HTMLTableRowElement>::firstChild(*child))
                return row;
        }
    }

    // If still looking at top level and bodies, find the next row in top level or the first in the next body section.
    if (!previous || isInSection(*previous, theadTag))
        child = Traversal<HTMLElement>::firstChild(table);
    else if (previous->parentNode() == table)
        child = Traversal<HTMLElement>::nextSibling(*previous);
    else if (isInSection(*previous, tbodyTag))
        child = Traversal<HTMLElement>::nextSibling(*previous->parentNode());
    for (; child; child = Traversal<HTMLElement>::nextSibling(*child)) {
        if (isHTMLTableRowElement(child))
            return toHTMLTableRowElement(child);
        if (child->hasTagName(tbodyTag)) {
            if (HTMLTableRowElement* row = Traversal<HTMLTableRowElement>::firstChild(*child))
                return row;
        }
    }

    // Find the first row in the next foot section.
    if (!previous || !isInSection(*previous, tfootTag))
        child = Traversal<HTMLElement>::firstChild(table);
    else
        child = Traversal<HTMLElement>::nextSibling(*previous->parentNode());
    for (; child; child = Traversal<HTMLElement>::nextSibling(*child)) {
        if (child->hasTagName(tfootTag)) {
            if (HTMLTableRowElement* row = Traversal<HTMLTableRowElement>::firstChild(*child))
                return row;
        }
    }

    return nullptr;
}

HTMLTableRowElement* HTMLTableRowsCollection::lastRow(HTMLTableElement& table)
{
    for (HTMLElement* tfoot = Traversal<HTMLElement>::lastChild(table, HasHTMLTagName(tfootTag)); tfoot; tfoot = Traversal<HTMLElement>::previousSibling(*tfoot, HasHTMLTagName(tfootTag))) {
        if (HTMLTableRowElement* lastRow = Traversal<HTMLTableRowElement>::lastChild(*tfoot))
            return lastRow;
    }

    for (HTMLElement* child = Traversal<HTMLElement>::lastChild(table); child; child = Traversal<HTMLElement>::previousSibling(*child)) {
        if (isHTMLTableRowElement(child))
            return toHTMLTableRowElement(child);
        if (child->hasTagName(tbodyTag)) {
            if (HTMLTableRowElement* lastRow = Traversal<HTMLTableRowElement>::lastChild(*child))
                return lastRow;
        }
    }

    for (HTMLElement* thead = Traversal<HTMLElement>::lastChild(table, HasHTMLTagName(theadTag)); thead; thead = Traversal<HTMLElement>::previousSibling(*thead, HasHTMLTagName(theadTag))) {
        if (HTMLTableRowElement* lastRow = Traversal<HTMLTableRowElement>::lastChild(*thead))
            return lastRow;
    }

    return nullptr;
}

// Must call get() on the table in case that argument is compiled before dereferencing the
// table to get at the collection cache. Order of argument evaluation is undefined and can
// differ between compilers.
HTMLTableRowsCollection::HTMLTableRowsCollection(ContainerNode& table)
    : HTMLCollection(table, TableRows, OverridesItemAfter)
{
    ASSERT(isHTMLTableElement(table));
}

RawPtr<HTMLTableRowsCollection> HTMLTableRowsCollection::create(ContainerNode& table, CollectionType type)
{
    ASSERT_UNUSED(type, type == TableRows);
    return new HTMLTableRowsCollection(table);
}

Element* HTMLTableRowsCollection::virtualItemAfter(Element* previous) const
{
    return rowAfter(toHTMLTableElement(ownerNode()), toHTMLTableRowElement(previous));
}

} // namespace blink
