styledelement.cpp

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            getInlineStyleDecl()->parseDeclaration(attr->value());
        m_isStyleAttributeValid = true;
        setChanged();
    }
}

void StyledElement::createAttributeMap() const
{
    namedAttrMap = NamedMappedAttrMap::create(const_cast<StyledElement*>(this));
}

CSSMutableStyleDeclaration* StyledElement::getInlineStyleDecl()
{
    if (!m_inlineStyleDecl)
        createInlineStyleDecl();
    return m_inlineStyleDecl.get();
}

CSSStyleDeclaration* StyledElement::style()
{
    return getInlineStyleDecl();
}

static inline int toHex(UChar c) {
    return ((c >= '0' && c <= '9') ? (c - '0')
        : ((c >= 'a' && c <= 'f') ? (c - 'a' + 10)
        : (( c >= 'A' && c <= 'F') ? (c - 'A' + 10)
        : -1)));
}

void StyledElement::addCSSProperty(MappedAttribute* attr, int id, const String &value)
{
    if (!attr->decl()) createMappedDecl(attr);
    attr->decl()->setProperty(id, value, false);
}

void StyledElement::addCSSProperty(MappedAttribute* attr, int id, int value)
{
    if (!attr->decl()) createMappedDecl(attr);
    attr->decl()->setProperty(id, value, false);
}

void StyledElement::addCSSStringProperty(MappedAttribute* attr, int id, const String &value, CSSPrimitiveValue::UnitTypes type)
{
    if (!attr->decl()) createMappedDecl(attr);
    attr->decl()->setStringProperty(id, value, type, false);
}

void StyledElement::addCSSImageProperty(MappedAttribute* attr, int id, const String& url)
{
    if (!attr->decl()) createMappedDecl(attr);
    attr->decl()->setImageProperty(id, url, false);
}

void StyledElement::addCSSLength(MappedAttribute* attr, int id, const String &value)
{
    // FIXME: This function should not spin up the CSS parser, but should instead just figure out the correct
    // length unit and make the appropriate parsed value.
    if (!attr->decl())
        createMappedDecl(attr);

    // strip attribute garbage..
    StringImpl* v = value.impl();
    if (v) {
        unsigned int l = 0;
        
        while (l < v->length() && (*v)[l] <= ' ')
            l++;
        
        for (; l < v->length(); l++) {
            UChar cc = (*v)[l];
            if (cc > '9')
                break;
            if (cc < '0') {
                if (cc == '%' || cc == '*')
                    l++;
                if (cc != '.')
                    break;
            }
        }

        if (l != v->length()) {
            attr->decl()->setLengthProperty(id, v->substring(0, l), false);
            return;
        }
    }
    
    attr->decl()->setLengthProperty(id, value, false);
}

/* color parsing that tries to match as close as possible IE 6. */
void StyledElement::addCSSColor(MappedAttribute* attr, int id, const String& c)
{
    // this is the only case no color gets applied in IE.
    if (!c.length())
        return;

    if (!attr->decl())
        createMappedDecl(attr);
    
    if (attr->decl()->setProperty(id, c, false))
        return;
    
    String color = c;
    // not something that fits the specs.
    
    // we're emulating IEs color parser here. It maps transparent to black, otherwise it tries to build a rgb value
    // out of everyhting you put in. The algorithm is experimentally determined, but seems to work for all test cases I have.
    
    // the length of the color value is rounded up to the next
    // multiple of 3. each part of the rgb triple then gets one third
    // of the length.
    //
    // Each triplet is parsed byte by byte, mapping
    // each number to a hex value (0-9a-fA-F to their values
    // everything else to 0).
    //
    // The highest non zero digit in all triplets is remembered, and
    // used as a normalization point to normalize to values between 0
    // and 255.
    
    if (!equalIgnoringCase(color, "transparent")) {
        if (color[0] == '#')
            color.remove(0, 1);
        int basicLength = (color.length() + 2) / 3;
        if (basicLength > 1) {
            // IE ignores colors with three digits or less
            int colors[3] = { 0, 0, 0 };
            int component = 0;
            int pos = 0;
            int maxDigit = basicLength-1;
            while (component < 3) {
                // search forward for digits in the string
                int numDigits = 0;
                while (pos < (int)color.length() && numDigits < basicLength) {
                    int hex = toHex(color[pos]);
                    colors[component] = (colors[component] << 4);
                    if (hex > 0) {
                        colors[component] += hex;
                        maxDigit = min(maxDigit, numDigits);
                    }
                    numDigits++;
                    pos++;
                }
                while (numDigits++ < basicLength)
                    colors[component] <<= 4;
                component++;
            }
            maxDigit = basicLength - maxDigit;
            
            // normalize to 00-ff. The highest filled digit counts, minimum is 2 digits
            maxDigit -= 2;
            colors[0] >>= 4*maxDigit;
            colors[1] >>= 4*maxDigit;
            colors[2] >>= 4*maxDigit;
            // ASSERT(colors[0] < 0x100 && colors[1] < 0x100 && colors[2] < 0x100);
            
            color = String::format("#%02x%02x%02x", colors[0], colors[1], colors[2]);
            if (attr->decl()->setProperty(id, color, false))
                return;
        }
    }
    attr->decl()->setProperty(id, CSSValueBlack, false);
}

void StyledElement::createMappedDecl(MappedAttribute* attr)
{
    RefPtr<CSSMappedAttributeDeclaration> decl = CSSMappedAttributeDeclaration::create();
    attr->setDecl(decl);
    decl->setParent(document()->elementSheet());
    decl->setNode(this);
    decl->setStrictParsing(false); // Mapped attributes are just always quirky.
}

// Paul Hsieh's SuperFastHash
// http://www.azillionmonkeys.com/qed/hash.html
unsigned MappedAttributeHash::hash(const MappedAttributeKey& key)
{
    uint32_t hash = WTF::stringHashingStartValue;
    uint32_t tmp;

    const uint16_t* p;

    p = reinterpret_cast<const uint16_t*>(&key.name);
    hash += p[0];
    tmp = (p[1] << 11) ^ hash;
    hash = (hash << 16) ^ tmp;
    hash += hash >> 11;
    ASSERT(sizeof(key.name) == 4 || sizeof(key.name) == 8);
    if (sizeof(key.name) == 8) {
        p += 2;
        hash += p[0];
        tmp = (p[1] << 11) ^ hash;
        hash = (hash << 16) ^ tmp;
        hash += hash >> 11;
    }

    p = reinterpret_cast<const uint16_t*>(&key.value);
    hash += p[0];
    tmp = (p[1] << 11) ^ hash;
    hash = (hash << 16) ^ tmp;
    hash += hash >> 11;
    ASSERT(sizeof(key.value) == 4 || sizeof(key.value) == 8);
    if (sizeof(key.value) == 8) {
        p += 2;
        hash += p[0];
        tmp = (p[1] << 11) ^ hash;
        hash = (hash << 16) ^ tmp;
        hash += hash >> 11;
    }

    // Handle end case
    hash += key.type;
    hash ^= hash << 11;
    hash += hash >> 17;

    // Force "avalanching" of final 127 bits
    hash ^= hash << 3;
    hash += hash >> 5;
    hash ^= hash << 2;
    hash += hash >> 15;
    hash ^= hash << 10;

    // This avoids ever returning a hash code of 0, since that is used to
    // signal "hash not computed yet", using a value that is likely to be
    // effectively the same as 0 when the low bits are masked
    if (hash == 0)
        hash = 0x80000000;

    return hash;
}

void StyledElement::copyNonAttributeProperties(const Element *sourceElement)
{
    const StyledElement* source = static_cast<const StyledElement*>(sourceElement);
    if (!source->m_inlineStyleDecl)
        return;

    *getInlineStyleDecl() = *source->m_inlineStyleDecl;
    m_isStyleAttributeValid = source->m_isStyleAttributeValid;
    m_synchronizingStyleAttribute = source->m_synchronizingStyleAttribute;
    
    Element::copyNonAttributeProperties(sourceElement);
}

void StyledElement::addSubresourceAttributeURLs(ListHashSet<KURL>& urls) const
{
    if (CSSMutableStyleDeclaration* style = inlineStyleDecl())
        style->addSubresourceStyleURLs(urls);
}

}