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#include "qv4regexpobject_p.h"
#include "qv4jsir_p.h"
#include "qv4isel_p.h"
#include "qv4objectproto_p.h"
#include "qv4stringobject_p.h"
#include "qv4mm_p.h"

#include <private/qqmljsengine_p.h>
#include <private/qqmljslexer_p.h>
#include <private/qqmljsparser_p.h>
#include <private/qqmljsast_p.h>
#include <qv4jsir_p.h>
#include <qv4codegen_p.h>
#include "private/qlocale_tools_p.h"

#include <QtCore/qmath.h>
#include <QtCore/QDebug>
#include <QtCore/qregexp.h>
#include <cassert>
#include <typeinfo>
#include <iostream>
#include "qv4alloca_p.h"

QT_BEGIN_NAMESPACE

Q_CORE_EXPORT QString qt_regexp_toCanonical(const QString &, QRegExp::PatternSyntax);

using namespace QV4;

DEFINE_MANAGED_VTABLE(RegExpObject);

RegExpObject::RegExpObject(InternalClass *ic)
    : Object(ic)
    , value(RegExp::create(ic->engine, QString(), false, false))
    , global(false)
{
    init(ic->engine);
}

RegExpObject::RegExpObject(ExecutionEngine *engine, RegExp* value, bool global)
    : Object(engine->regExpClass)
    , value(value)
    , global(global)
{
    init(engine);
}

// Converts a QRegExp to a JS RegExp.
// The conversion is not 100% exact since ECMA regexp and QRegExp
// have different semantics/flags, but we try to do our best.
RegExpObject::RegExpObject(ExecutionEngine *engine, const QRegExp &re)
    : Object(engine->regExpClass)
    , value(0)
    , global(false)
{
    // Convert the pattern to a ECMAScript pattern.
    QString pattern = QT_PREPEND_NAMESPACE(qt_regexp_toCanonical)(re.pattern(), re.patternSyntax());
    if (re.isMinimal()) {
        QString ecmaPattern;
        int len = pattern.length();
        ecmaPattern.reserve(len);
        int i = 0;
        const QChar *wc = pattern.unicode();
        bool inBracket = false;
        while (i < len) {
            QChar c = wc[i++];
            ecmaPattern += c;
            switch (c.unicode()) {
            case '?':
            case '+':
            case '*':
            case '}':
                if (!inBracket)
                    ecmaPattern += QLatin1Char('?');
                break;
            case '\\':
                if (i < len)
                    ecmaPattern += wc[i++];
                break;
            case '[':
                inBracket = true;
                break;
            case ']':
                inBracket = false;
                break;
            default:
                break;
            }
        }
        pattern = ecmaPattern;
    }

    value = RegExp::create(engine, pattern, re.caseSensitivity() == Qt::CaseInsensitive, false);

    init(engine);
}

void RegExpObject::init(ExecutionEngine *engine)
{
    vtbl = &static_vtbl;
    type = Type_RegExpObject;

    Property *lastIndexProperty = insertMember(engine->newIdentifier(QStringLiteral("lastIndex")),
                                                         Attr_NotEnumerable|Attr_NotConfigurable);
    lastIndexProperty->value = Value::fromInt32(0);
    if (!this->value)
        return;

    QString p = this->value->pattern();
    if (p.isEmpty()) {
        p = QStringLiteral("(?:)");
    } else {
        // escape certain parts, see ch. 15.10.4
        p.replace('/', QLatin1String("\\/"));
    }

    defineReadonlyProperty(engine->newIdentifier(QStringLiteral("source")), Value::fromString(engine->newString(p)));
    defineReadonlyProperty(engine->newIdentifier(QStringLiteral("global")), Value::fromBoolean(global));
    defineReadonlyProperty(engine->newIdentifier(QStringLiteral("ignoreCase")), Value::fromBoolean(this->value->ignoreCase()));
    defineReadonlyProperty(engine->newIdentifier(QStringLiteral("multiline")), Value::fromBoolean(this->value->multiLine()));
}


void RegExpObject::destroy(Managed *that)
{
    static_cast<RegExpObject *>(that)->~RegExpObject();
}

void RegExpObject::markObjects(Managed *that)
{
    RegExpObject *re = static_cast<RegExpObject*>(that);
    if (re->value)
        re->value->mark();
    Object::markObjects(that);
}

Property *RegExpObject::lastIndexProperty(ExecutionContext *ctx)
{
    Q_ASSERT(0 == internalClass->find(ctx->engine->newIdentifier(QStringLiteral("lastIndex"))));
    return &memberData[0];
}

// Converts a JS RegExp to a QRegExp.
// The conversion is not 100% exact since ECMA regexp and QRegExp
// have different semantics/flags, but we try to do our best.
QRegExp RegExpObject::toQRegExp() const
{
    Qt::CaseSensitivity caseSensitivity = value->ignoreCase() ? Qt::CaseInsensitive : Qt::CaseSensitive;
    return QRegExp(value->pattern(), caseSensitivity, QRegExp::RegExp2);
}

QString RegExpObject::toString() const
{
    QString result = QChar('/') + source();
    result += QChar('/');
    if (global)
        result += QChar('g');
    if (value->ignoreCase())
        result += QChar('i');
    if (value->multiLine())
        result += QChar('m');
    return result;
}

QString RegExpObject::source() const
{
    return const_cast<RegExpObject *>(this)->get(internalClass->engine->newIdentifier(QStringLiteral("source"))).stringValue()->toQString();
}

uint RegExpObject::flags() const
{
    uint f = 0;
    if (global)
        f |= QV4::RegExpObject::RegExp_Global;
    if (value->ignoreCase())
        f |= QV4::RegExpObject::RegExp_IgnoreCase;
    if (value->multiLine())
        f |= QV4::RegExpObject::RegExp_Multiline;
    return f;
}

DEFINE_MANAGED_VTABLE(RegExpCtor);

RegExpCtor::RegExpCtor(ExecutionContext *scope)
    : FunctionObject(scope, scope->engine->newIdentifier(QStringLiteral("RegExp")))
{
    vtbl = &static_vtbl;
}

Value RegExpCtor::construct(Managed *m, const CallData &d)
{
    Value r = d.argc > 0 ? d.args[0] : Value::undefinedValue();
    Value f = d.argc > 1 ? d.args[1] : Value::undefinedValue();
    ExecutionContext *ctx = m->engine()->current;
    if (RegExpObject *re = r.as<RegExpObject>()) {
        if (!f.isUndefined())
            ctx->throwTypeError();

        RegExpObject *o = ctx->engine->newRegExpObject(re->value, re->global);
        return Value::fromObject(o);
    }

    QString pattern;
    if (!r.isUndefined())
        pattern = r.toString(ctx)->toQString();

    bool global = false;
    bool ignoreCase = false;
    bool multiLine = false;
    if (!f.isUndefined()) {
        f = __qmljs_to_string(f, ctx);
        QString str = f.stringValue()->toQString();
        for (int i = 0; i < str.length(); ++i) {
            if (str.at(i) == QChar('g') && !global) {
                global = true;
            } else if (str.at(i) == QChar('i') && !ignoreCase) {
                ignoreCase = true;
            } else if (str.at(i) == QChar('m') && !multiLine) {
                multiLine = true;
            } else {
                ctx->throwSyntaxError(0);
            }
        }
    }

    RegExp* re = RegExp::create(ctx->engine, pattern, ignoreCase, multiLine);
    if (!re->isValid())
        ctx->throwSyntaxError(0);

    RegExpObject *o = ctx->engine->newRegExpObject(re, global);
    return Value::fromObject(o);
}

Value RegExpCtor::call(Managed *that, const CallData &d)
{
    if (d.argc > 0 && d.args[0].as<RegExpObject>()) {
        if (d.argc == 1 || d.args[1].isUndefined())
            return d.args[0];
    }

    return construct(that, d);
}

void RegExpPrototype::init(ExecutionContext *ctx, const Value &ctor)
{
    ctor.objectValue()->defineReadonlyProperty(ctx->engine->id_prototype, Value::fromObject(this));
    ctor.objectValue()->defineReadonlyProperty(ctx->engine->id_length, Value::fromInt32(2));
    defineDefaultProperty(ctx, QStringLiteral("constructor"), ctor);
    defineDefaultProperty(ctx, QStringLiteral("exec"), method_exec, 1);
    defineDefaultProperty(ctx, QStringLiteral("test"), method_test, 1);
    defineDefaultProperty(ctx, QStringLiteral("toString"), method_toString, 0);
    defineDefaultProperty(ctx, QStringLiteral("compile"), method_compile, 2);
}

Value RegExpPrototype::method_exec(SimpleCallContext *ctx)
{
    RegExpObject *r = ctx->thisObject.as<RegExpObject>();
    if (!r)
        ctx->throwTypeError();

    Value arg = ctx->argument(0);
    arg = __qmljs_to_string(arg, ctx);
    QString s = arg.stringValue()->toQString();

    int offset = r->global ? r->lastIndexProperty(ctx)->value.toInt32() : 0;
    if (offset < 0 || offset > s.length()) {
        r->lastIndexProperty(ctx)->value = Value::fromInt32(0);
        return Value::nullValue();
    }

    uint* matchOffsets = (uint*)alloca(r->value->captureCount() * 2 * sizeof(uint));
    int result = r->value->match(s, offset, matchOffsets);
    if (result == -1) {
        r->lastIndexProperty(ctx)->value = Value::fromInt32(0);
        return Value::nullValue();
    }

    // fill in result data
    ArrayObject *array = ctx->engine->newArrayObject(ctx->engine->regExpExecArrayClass);
    int len = r->value->captureCount();
    array->arrayReserve(len);
    for (int i = 0; i < len; ++i) {
        int start = matchOffsets[i * 2];
        int end = matchOffsets[i * 2 + 1];
        array->arrayData[i].value = (start != -1 && end != -1) ? Value::fromString(ctx, s.mid(start, end - start)) : Value::undefinedValue();
    }
    array->arrayDataLen = len;
    array->setArrayLengthUnchecked(len);

    array->memberData[Index_ArrayIndex].value = Value::fromInt32(result);
    array->memberData[Index_ArrayInput].value = arg;

    if (r->global)
        r->lastIndexProperty(ctx)->value = Value::fromInt32(matchOffsets[1]);

    return Value::fromObject(array);
}

Value RegExpPrototype::method_test(SimpleCallContext *ctx)
{
    Value r = method_exec(ctx);
    return Value::fromBoolean(!r.isNull());
}

Value RegExpPrototype::method_toString(SimpleCallContext *ctx)
{
    RegExpObject *r = ctx->thisObject.as<RegExpObject>();
    if (!r)
        ctx->throwTypeError();

    return Value::fromString(ctx, r->toString());
}

Value RegExpPrototype::method_compile(SimpleCallContext *ctx)
{
    RegExpObject *r = ctx->thisObject.as<RegExpObject>();
    if (!r)
        ctx->throwTypeError();

    CallData d;
    d.args = ctx->arguments;
    d.argc = ctx->argumentCount;
    RegExpObject *re = ctx->engine->regExpCtor.asFunctionObject()->construct(d).as<RegExpObject>();

    r->value = re->value;
    r->global = re->global;
    return Value::undefinedValue();
}

QT_END_NAMESPACE