1/*
2 * Copyright (C) 2011 Leo Yang <leoyang@webkit.org>
3 *
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
8 *
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12 * Library General Public License for more details.
13 *
14 * You should have received a copy of the GNU Library General Public License
15 * along with this library; see the file COPYING.LIB.  If not, write to
16 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
17 * Boston, MA 02110-1301, USA.
18 */
19
20#include "config.h"
21
22#if ENABLE(SVG_FONTS)
23#include "core/svg/SVGAltGlyphItemElement.h"
24
25#include "core/dom/ElementTraversal.h"
26#include "core/svg/SVGGlyphRefElement.h"
27
28namespace blink {
29
30inline SVGAltGlyphItemElement::SVGAltGlyphItemElement(Document& document)
31    : SVGElement(SVGNames::altGlyphItemTag, document)
32{
33}
34
35DEFINE_NODE_FACTORY(SVGAltGlyphItemElement)
36
37bool SVGAltGlyphItemElement::hasValidGlyphElements(Vector<AtomicString>& glyphNames) const
38{
39    // Spec: http://www.w3.org/TR/SVG/text.html#AltGlyphItemElement
40    // The ‘altGlyphItem’ element defines a candidate set of possible glyph substitutions.
41    // The first ‘altGlyphItem’ element whose referenced glyphs are all available is chosen.
42    // Its glyphs are rendered instead of the character(s) that are inside of the referencing
43    // ‘altGlyph’ element.
44    //
45    // Here we fill glyphNames and return true only if all referenced glyphs are valid and
46    // there is at least one glyph.
47    for (SVGGlyphRefElement* glyph = Traversal<SVGGlyphRefElement>::firstChild(*this); glyph; glyph = Traversal<SVGGlyphRefElement>::nextSibling(*glyph)) {
48        AtomicString referredGlyphName;
49        if (glyph->hasValidGlyphElement(referredGlyphName)) {
50            glyphNames.append(referredGlyphName);
51        } else {
52            glyphNames.clear();
53            return false;
54        }
55    }
56    return !glyphNames.isEmpty();
57}
58
59}
60
61#endif
62