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#include "qv4string_p.h"
#include "qv4value_p.h"
#ifndef V4_BOOTSTRAP
#include "qv4identifiertable_p.h"
#include "qv4runtime_p.h"
#include "qv4objectproto_p.h"
#include "qv4stringobject_p.h"
#endif
#include <QtCore/QHash>
#include <QtCore/private/qnumeric_p.h>

using namespace QV4;

#ifndef V4_BOOTSTRAP

DEFINE_MANAGED_VTABLE(String);

void String::markObjects(Heap::Base *that, ExecutionEngine *e)
{
    String::Data *s = static_cast<String::Data *>(that);
    if (s->largestSubLength) {
        s->left->mark(e);
        s->right->mark(e);
    }
}

bool String::isEqualTo(Managed *t, Managed *o)
{
    if (t == o)
        return true;

    if (!o->d()->vtable()->isString)
        return false;

    return static_cast<String *>(t)->isEqualTo(static_cast<String *>(o));
}


void Heap::String::init(const QString &t)
{
    Base::init();

    subtype = String::StringType_Unknown;

    text = const_cast<QString &>(t).data_ptr();
    text->ref.ref();
    identifier = 0;
    stringHash = UINT_MAX;
    largestSubLength = 0;
    len = text->size;
}

void Heap::String::init(String *l, String *r)
{
    Base::init();

    subtype = String::StringType_Unknown;

    left = l;
    right = r;
    stringHash = UINT_MAX;
    largestSubLength = qMax(l->largestSubLength, r->largestSubLength);
    len = l->len + r->len;
    Q_ASSERT(largestSubLength <= len);

    if (!l->largestSubLength && l->len > largestSubLength)
        largestSubLength = l->len;
    if (!r->largestSubLength && r->len > largestSubLength)
        largestSubLength = r->len;

    // make sure we don't get excessive depth in our strings
    if (len > 256 && len >= 2*largestSubLength)
        simplifyString();
}

void Heap::String::destroy() {
    if (!largestSubLength) {
        internalClass->engine->memoryManager->changeUnmanagedHeapSizeUsage(qptrdiff(-text->size) * (int)sizeof(QChar));
        if (!text->ref.deref())
            QStringData::deallocate(text);
    }
    Base::destroy();
}

uint String::toUInt(bool *ok) const
{
    *ok = true;

    if (subtype() == Heap::String::StringType_Unknown)
        d()->createHashValue();
    if (subtype() == Heap::String::StringType_ArrayIndex)
        return d()->stringHash;

    // required for UINT_MAX or numbers starting with a leading 0
    double d = RuntimeHelpers::stringToNumber(toQString());
    uint l = (uint)d;
    if (d == l)
        return l;
    *ok = false;
    return UINT_MAX;
}

void String::makeIdentifierImpl() const
{
    if (d()->largestSubLength)
        d()->simplifyString();
    Q_ASSERT(!d()->largestSubLength);
    engine()->identifierTable->identifier(this);
}

void Heap::String::simplifyString() const
{
    Q_ASSERT(largestSubLength);

    int l = length();
    QString result(l, Qt::Uninitialized);
    QChar *ch = const_cast<QChar *>(result.constData());
    append(this, ch);
    text = result.data_ptr();
    text->ref.ref();
    identifier = 0;
    largestSubLength = 0;
    internalClass->engine->memoryManager->changeUnmanagedHeapSizeUsage(qptrdiff(text->size) * (qptrdiff)sizeof(QChar));
}

void Heap::String::append(const String *data, QChar *ch)
{
    std::vector<const String *> worklist;
    worklist.reserve(32);
    worklist.push_back(data);

    while (!worklist.empty()) {
        const String *item = worklist.back();
        worklist.pop_back();

        if (item->largestSubLength) {
            worklist.push_back(item->right);
            worklist.push_back(item->left);
        } else {
            memcpy(ch, item->text->data(), item->text->size * sizeof(QChar));
            ch += item->text->size;
        }
    }
}

void Heap::String::createHashValue() const
{
    if (largestSubLength)
        simplifyString();
    Q_ASSERT(!largestSubLength);
    const QChar *ch = reinterpret_cast<const QChar *>(text->data());
    const QChar *end = ch + text->size;
    stringHash = QV4::String::calculateHashValue(ch, end, &subtype);
}

uint String::getLength(const Managed *m)
{
    return static_cast<const String *>(m)->d()->length();
}

#endif // V4_BOOTSTRAP

uint String::toArrayIndex(const QString &str)
{
    return QV4::String::toArrayIndex(str.constData(), str.constData() + str.length());
}