Source/WebCore/css/CSSGroupingRule.cpp

/*
 * Copyright (C) 2011 Adobe Systems Incorporated. All rights reserved.
 * Copyright (C) 2012 Apple Inc. All rights reserved.
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#include "config.h"

#include "CSSGroupingRule.h"

#include "CSSParser.h"
#include "CSSRuleList.h"
#include "CSSStyleSheet.h"
#include "StyleRule.h"
#include <wtf/text/StringBuilder.h>

namespace WebCore {

CSSGroupingRule::CSSGroupingRule(StyleRuleGroup& groupRule, CSSStyleSheet* parent)
    : CSSRule(parent)
    , m_groupRule(groupRule)
    , m_childRuleCSSOMWrappers(groupRule.childRules().size())
{
}

CSSGroupingRule::~CSSGroupingRule()
{
    ASSERT(m_childRuleCSSOMWrappers.size() == m_groupRule->childRules().size());
    for (unsigned i = 0; i < m_childRuleCSSOMWrappers.size(); ++i) {
        if (m_childRuleCSSOMWrappers[i])
            m_childRuleCSSOMWrappers[i]->setParentRule(0);
    }
}

ExceptionOr<unsigned> CSSGroupingRule::insertRule(const String& ruleString, unsigned index)
{
    ASSERT(m_childRuleCSSOMWrappers.size() == m_groupRule->childRules().size());

    if (index > m_groupRule->childRules().size()) {
        // IndexSizeError: Raised if the specified index is not a valid insertion point.
        return Exception { IndexSizeError };
    }

    CSSStyleSheet* styleSheet = parentStyleSheet();
    RefPtr<StyleRuleBase> newRule = CSSParser::parseRule(parserContext(), styleSheet ? &styleSheet->contents() : nullptr, ruleString);
    if (!newRule) {
        // SyntaxError: Raised if the specified rule has a syntax error and is unparsable.
        return Exception { SyntaxError };
    }

    if (newRule->isImportRule() || newRule->isNamespaceRule()) {
        // FIXME: an HierarchyRequestError should also be thrown for a @charset or a nested
        // @media rule. They are currently not getting parsed, resulting in a SyntaxError
        // to get raised above.

        // HierarchyRequestError: Raised if the rule cannot be inserted at the specified
        // index, e.g., if an @import rule is inserted after a standard rule set or other
        // at-rule.
        return Exception { HierarchyRequestError };
    }
    CSSStyleSheet::RuleMutationScope mutationScope(this);

    m_groupRule->wrapperInsertRule(index, newRule.releaseNonNull());

    m_childRuleCSSOMWrappers.insert(index, RefPtr<CSSRule>());
    return index;
}

ExceptionOr<void> CSSGroupingRule::deleteRule(unsigned index)
{
    ASSERT(m_childRuleCSSOMWrappers.size() == m_groupRule->childRules().size());

    if (index >= m_groupRule->childRules().size()) {
        // IndexSizeError: Raised if the specified index does not correspond to a
        // rule in the media rule list.
        return Exception { IndexSizeError };
    }

    CSSStyleSheet::RuleMutationScope mutationScope(this);

    m_groupRule->wrapperRemoveRule(index);

    if (m_childRuleCSSOMWrappers[index])
        m_childRuleCSSOMWrappers[index]->setParentRule(0);
    m_childRuleCSSOMWrappers.remove(index);

    return { };
}

void CSSGroupingRule::appendCssTextForItems(StringBuilder& result) const
{
    unsigned size = length();
    for (unsigned i = 0; i < size; ++i) {
        result.appendLiteral("  ");
        result.append(item(i)->cssText());
        result.append('\n');
    }
}

unsigned CSSGroupingRule::length() const
{ 
    return m_groupRule->childRules().size(); 
}

CSSRule* CSSGroupingRule::item(unsigned index) const
{ 
    if (index >= length())
        return nullptr;
    ASSERT(m_childRuleCSSOMWrappers.size() == m_groupRule->childRules().size());
    RefPtr<CSSRule>& rule = m_childRuleCSSOMWrappers[index];
    if (!rule)
        rule = m_groupRule->childRules()[index]->createCSSOMWrapper(const_cast<CSSGroupingRule*>(this));
    return rule.get();
}

CSSRuleList& CSSGroupingRule::cssRules() const
{
    if (!m_ruleListCSSOMWrapper)
        m_ruleListCSSOMWrapper = makeUnique<LiveCSSRuleList<CSSGroupingRule>>(const_cast<CSSGroupingRule&>(*this));
    return *m_ruleListCSSOMWrapper;
}

void CSSGroupingRule::reattach(StyleRuleBase& rule)
{
    m_groupRule = static_cast<StyleRuleGroup&>(rule);
    for (unsigned i = 0; i < m_childRuleCSSOMWrappers.size(); ++i) {
        if (m_childRuleCSSOMWrappers[i])
            m_childRuleCSSOMWrappers[i]->reattach(*m_groupRule.get().childRules()[i]);
    }
}

} // namespace WebCore