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#ifndef QV4JSCALL_H
#define QV4JSCALL_H

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//

#include "qv4object_p.h"
#include "qv4function_p.h"
#include "qv4functionobject_p.h"
#include "qv4context_p.h"
#include "qv4scopedvalue_p.h"

QT_BEGIN_NAMESPACE

namespace QV4 {

struct JSCallData {
    JSCallData(const Scope &scope, std::nullptr_t, int argc = 0)
    {
        int size = int(offsetof(QV4::CallData, args)/sizeof(QV4::Value)) + argc;
        ptr = reinterpret_cast<CallData *>(scope.alloc(size));
        ptr->setArgc(argc);
    }
    JSCallData(const Scope &scope, const FunctionObject *function, int argc = 0)
    {
        int size = int(offsetof(QV4::CallData, args)/sizeof(QV4::Value)) + argc;
        ptr = reinterpret_cast<CallData *>(scope.alloc(size));
        ptr->setArgc(argc);
        ptr->function = *function;
    }
    JSCallData(const Scope &scope, Heap::FunctionObject *function, int argc = 0)
    {
        int size = int(offsetof(QV4::CallData, args)/sizeof(QV4::Value)) + argc;
        ptr = reinterpret_cast<CallData *>(scope.alloc(size));
        ptr->setArgc(argc);
        ptr->function = function;
    }
    JSCallData(const Scope &scope, Value *argv, int argc, Value *thisObject = 0)
    {
        int size = int(offsetof(QV4::CallData, args)/sizeof(QV4::Value)) + argc;
        ptr = reinterpret_cast<CallData *>(scope.engine->jsStackTop);
        scope.engine->jsStackTop += size;
        ptr->function = Encode::undefined();
        ptr->context = Encode::undefined();
        ptr->accumulator = Encode::undefined();
        ptr->thisObject = thisObject ? thisObject->asReturnedValue() : Encode::undefined();
        ptr->setArgc(argc);
        memcpy(ptr->args, argv, argc*sizeof(Value));
    }
    JSCallData(const Scope &scope, ReturnedValue function, const Value *argv, int argc, const Value *thisObject = 0)
    {
        int size = int(offsetof(QV4::CallData, args)/sizeof(QV4::Value)) + argc;
        ptr = reinterpret_cast<CallData *>(scope.engine->jsStackTop);
        scope.engine->jsStackTop += size;
        ptr->function = function;
        ptr->context = Encode::undefined();
        ptr->accumulator = Encode::undefined();
        ptr->thisObject = thisObject ? thisObject->asReturnedValue() : Encode::undefined();
        ptr->setArgc(argc);
        memcpy(ptr->args, argv, argc*sizeof(Value));
    }

    CallData *operator->() {
        return ptr;
    }

    operator CallData *() const {
        return ptr;
    }

    ReturnedValue call() const {
        return static_cast<FunctionObject &>(ptr->function).call(&ptr->thisObject, ptr->args, ptr->argc());
    }

    ReturnedValue callAsConstructor() const {
        return static_cast<FunctionObject &>(ptr->function).callAsConstructor(ptr->args, ptr->argc());
    }

    CallData *ptr;
};

struct ScopedStackFrame {
    Scope &scope;
    CppStackFrame frame;

    ScopedStackFrame(Scope &scope, Heap::ExecutionContext *context)
        : scope(scope)
    {
        frame.parent = scope.engine->currentStackFrame;
        if (!context)
            return;
        frame.jsFrame = reinterpret_cast<CallData *>(scope.alloc(sizeof(CallData)/sizeof(Value)));
        frame.jsFrame->context = context;
        frame.v4Function = frame.parent ? frame.parent->v4Function : 0;
        scope.engine->currentStackFrame = &frame;
    }
    ~ScopedStackFrame() {
        scope.engine->currentStackFrame = frame.parent;
    }
};

}

QT_END_NAMESPACE

#endif // QV4JSCALL_H