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** This file is part of the QtQml module of the Qt Toolkit.
**
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** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
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** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
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#include <QString>
#include "qv4debugging_p.h"
#include <qv4context_p.h>
#include <qv4object_p.h>
#include <qv4objectproto_p.h>
#include "qv4mm_p.h"
#include <qv4argumentsobject_p.h>
#include "qv4function_p.h"
#include "qv4errorobject_p.h"

using namespace QV4;

CallContext *ExecutionContext::newCallContext(void *stackSpace, FunctionObject *function, const CallData &d)
{
    CallContext *c = (CallContext *)stackSpace;
#ifndef QT_NO_DEBUG
    c->next = (CallContext *)0x1;
#endif

    engine->current = c;

    c->initBaseContext(Type_CallContext, engine, this);

    c->function = function;
    c->arguments = d.args;
    c->realArgumentCount = d.argc;
    c->argumentCount = d.argc;
    c->thisObject = d.thisObject;

    c->strictMode = function->strictMode;
    c->marked = false;
    c->outer = function->scope;
#ifndef QT_NO_DEBUG
    assert(c->outer->next != (ExecutionContext *)0x1);
#endif

    c->activation = 0;

    if (function->function) {
        c->compilationUnit = function->function->compilationUnit;
        c->compiledFunction = function->function->compiledFunction;
        c->lookups = c->compilationUnit->runtimeLookups;
        c->runtimeStrings = c->compilationUnit->runtimeStrings;
    }

    c->locals = (Value *)(c + 1);

    if (function->varCount)
        std::fill(c->locals, c->locals + function->varCount, Value::undefinedValue());

    if (d.argc < function->formalParameterCount) {
#ifndef QT_NO_DEBUG
        Q_ASSERT(function->formalParameterCount <= QV4::Global::ReservedArgumentCount);
#endif
        std::fill(c->arguments + d.argc, c->arguments + function->formalParameterCount, Value::undefinedValue());
        c->argumentCount = function->formalParameterCount;
    }

    return c;
}

CallContext *ExecutionContext::newCallContext(FunctionObject *function, const CallData &d)
{
    CallContext *c = static_cast<CallContext *>(engine->memoryManager->allocContext(requiredMemoryForExecutionContect(function, d.argc)));

    engine->current = c;

    c->initBaseContext(Type_CallContext, engine, this);

    c->function = function;
    c->arguments = d.args;
    c->realArgumentCount = d.argc;
    c->argumentCount = d.argc;
    c->thisObject = d.thisObject;

    c->strictMode = function->strictMode;
    c->marked = false;
    c->outer = function->scope;
#ifndef QT_NO_DEBUG
    assert(c->outer->next != (ExecutionContext *)0x1);
#endif

    c->activation = 0;

    if (function->function) {
        c->compilationUnit = function->function->compilationUnit;
        c->compiledFunction = function->function->compiledFunction;
        c->lookups = c->compilationUnit->runtimeLookups;
        c->runtimeStrings = c->compilationUnit->runtimeStrings;
    }

    c->locals = (Value *)(c + 1);

    if (function->varCount)
        std::fill(c->locals, c->locals + function->varCount, Value::undefinedValue());

    c->argumentCount = qMax((uint)d.argc, function->formalParameterCount);
    c->arguments = c->locals + function->varCount;
    if (d.argc)
        ::memcpy(c->arguments, d.args, c->realArgumentCount * sizeof(Value));
    if (d.argc < function->formalParameterCount)
        std::fill(c->arguments + d.argc, c->arguments + function->formalParameterCount, Value::undefinedValue());

    return c;
}

WithContext *ExecutionContext::newWithContext(Object *with)
{
    WithContext *w = static_cast<WithContext *>(engine->memoryManager->allocContext(sizeof(WithContext)));
    engine->current = w;
    w->initWithContext(this, with);
    return w;
}

CatchContext *ExecutionContext::newCatchContext(String *exceptionVarName, const Value &exceptionValue)
{
    CatchContext *c = static_cast<CatchContext *>(engine->memoryManager->allocContext(sizeof(CatchContext)));
    engine->current = c;
    c->initCatchContext(this, exceptionVarName, exceptionValue);
    return c;
}

CallContext *ExecutionContext::newQmlContext(FunctionObject *f, Object *qml)
{
    CallContext *c = static_cast<CallContext *>(engine->memoryManager->allocContext(requiredMemoryForExecutionContect(f, 0)));

    engine->current = c;
    c->initQmlContext(this, qml, f);

    return c;
}



void ExecutionContext::createMutableBinding(String *name, bool deletable)
{

    // find the right context to create the binding on
    Object *activation = engine->globalObject;
    ExecutionContext *ctx = this;
    while (ctx) {
        if (ctx->type >= Type_CallContext) {
            CallContext *c = static_cast<CallContext *>(ctx);
            if (!c->activation)
                c->activation = engine->newObject();
            activation = c->activation;
            break;
        }
        ctx = ctx->outer;
    }

    if (activation->__hasProperty__(name))
        return;
    Property desc = Property::fromValue(Value::undefinedValue());
    PropertyAttributes attrs(Attr_Data);
    attrs.setConfigurable(deletable);
    activation->__defineOwnProperty__(this, name, desc, attrs);
}

String * const *ExecutionContext::formals() const
{
    return type >= Type_CallContext ? static_cast<const CallContext *>(this)->function->formalParameterList : 0;
}

unsigned int ExecutionContext::formalCount() const
{
    return type >= Type_CallContext ? static_cast<const CallContext *>(this)->function->formalParameterCount : 0;
}

String * const *ExecutionContext::variables() const
{
    return type >= Type_CallContext ? static_cast<const CallContext *>(this)->function->varList : 0;
}

unsigned int ExecutionContext::variableCount() const
{
    return type >= Type_CallContext ? static_cast<const CallContext *>(this)->function->varCount : 0;
}


void GlobalContext::initGlobalContext(ExecutionEngine *eng)
{
    initBaseContext(Type_GlobalContext, eng, /*parentContext*/0);
    thisObject = Value::fromObject(eng->globalObject);
    global = 0;
}

void WithContext::initWithContext(ExecutionContext *p, Object *with)
{
    initBaseContext(Type_WithContext, p->engine, p);
    thisObject = p->thisObject;
    outer = p;
    lookups = p->lookups;
    runtimeStrings = p->runtimeStrings;
    compilationUnit = p->compilationUnit;
    compiledFunction = p->compiledFunction;

    withObject = with;
}

void CatchContext::initCatchContext(ExecutionContext *p, String *exceptionVarName, const Value &exceptionValue)
{
    initBaseContext(Type_CatchContext, p->engine, p);
    strictMode = p->strictMode;
    thisObject = p->thisObject;
    outer = p;
    lookups = p->lookups;
    runtimeStrings = p->runtimeStrings;
    compilationUnit = p->compilationUnit;
    compiledFunction = p->compiledFunction;

    this->exceptionVarName = exceptionVarName;
    this->exceptionValue = exceptionValue;
}

void CallContext::initQmlContext(ExecutionContext *parentContext, Object *qml, FunctionObject *function)
{
    initBaseContext(Type_QmlContext, parentContext->engine, parentContext);

    this->function = function;
    this->arguments = 0;
    this->argumentCount = 0;
    this->thisObject = Value::undefinedValue();

    strictMode = true;
    marked = false;
    this->outer = function->scope;
#ifndef QT_NO_DEBUG
    assert(outer->next != (ExecutionContext *)0x1);
#endif

    activation = qml;

    compilationUnit = function->function->compilationUnit;
    compiledFunction = function->function->compiledFunction;
    lookups = compilationUnit->runtimeLookups;
    runtimeStrings = compilationUnit->runtimeStrings;

    locals = (Value *)(this + 1);
    if (function->varCount)
        std::fill(locals, locals + function->varCount, Value::undefinedValue());
}


bool ExecutionContext::deleteProperty(String *name)
{
    bool hasWith = false;
    for (ExecutionContext *ctx = this; ctx; ctx = ctx->outer) {
        if (ctx->type == Type_WithContext) {
            hasWith = true;
            WithContext *w = static_cast<WithContext *>(ctx);
            if (w->withObject->__hasProperty__(name))
                return w->withObject->deleteProperty(name);
        } else if (ctx->type == Type_CatchContext) {
            CatchContext *c = static_cast<CatchContext *>(ctx);
            if (c->exceptionVarName->isEqualTo(name))
                return false;
        } else if (ctx->type >= Type_CallContext) {
            CallContext *c = static_cast<CallContext *>(ctx);
            FunctionObject *f = c->function;
            if (f->needsActivation || hasWith) {
                for (unsigned int i = 0; i < f->varCount; ++i)
                    if (f->varList[i]->isEqualTo(name))
                        return false;
                for (int i = (int)f->formalParameterCount - 1; i >= 0; --i)
                    if (f->formalParameterList[i]->isEqualTo(name))
                        return false;
            }
            if (c->activation && c->activation->__hasProperty__(name))
                return c->activation->deleteProperty(name);
        } else if (ctx->type == Type_GlobalContext) {
            GlobalContext *g = static_cast<GlobalContext *>(ctx);
            if (g->global->__hasProperty__(name))
                return g->global->deleteProperty(name);
        }
    }

    if (strictMode)
        throwSyntaxError(QString("Can't delete property %1").arg(name->toQString()));
    return true;
}

bool CallContext::needsOwnArguments() const
{
    return function->needsActivation || argumentCount < function->formalParameterCount;
}

void ExecutionContext::mark()
{
    if (marked)
        return;
    marked = true;

    if (type != Type_SimpleCallContext && outer)
        outer->mark();

    thisObject.mark();

    if (type >= Type_SimpleCallContext) {
        QV4::CallContext *c = static_cast<CallContext *>(this);
        for (unsigned arg = 0, lastArg = c->argumentCount; arg < lastArg; ++arg)
            c->arguments[arg].mark();
        if (type >= Type_CallContext) {
            for (unsigned local = 0, lastLocal = c->variableCount(); local < lastLocal; ++local)
                c->locals[local].mark();
            if (c->activation)
                c->activation->mark();
            c->function->mark();
        }
    } else if (type == Type_WithContext) {
        WithContext *w = static_cast<WithContext *>(this);
        w->withObject->mark();
    } else if (type == Type_CatchContext) {
        CatchContext *c = static_cast<CatchContext *>(this);
        if (c->exceptionVarName)
            c->exceptionVarName->mark();
        c->exceptionValue.mark();
    } else if (type == Type_GlobalContext) {
        GlobalContext *g = static_cast<GlobalContext *>(this);
        g->global->mark();
    }
}

void ExecutionContext::setProperty(String *name, const Value& value)
{
    for (ExecutionContext *ctx = this; ctx; ctx = ctx->outer) {
        if (ctx->type == Type_WithContext) {
            Object *w = static_cast<WithContext *>(ctx)->withObject;
            if (w->__hasProperty__(name)) {
                w->put(name, value);
                return;
            }
        } else if (ctx->type == Type_CatchContext && static_cast<CatchContext *>(ctx)->exceptionVarName->isEqualTo(name)) {
            static_cast<CatchContext *>(ctx)->exceptionValue = value;
            return;
        } else {
            Object *activation = 0;
            if (ctx->type >= Type_CallContext) {
                CallContext *c = static_cast<CallContext *>(ctx);
                for (unsigned int i = 0; i < c->function->varCount; ++i)
                    if (c->function->varList[i]->isEqualTo(name)) {
                        c->locals[i] = value;
                        return;
                    }
                for (int i = (int)c->function->formalParameterCount - 1; i >= 0; --i)
                    if (c->function->formalParameterList[i]->isEqualTo(name)) {
                        c->arguments[i] = value;
                        return;
                    }
                activation = c->activation;
            } else if (ctx->type == Type_GlobalContext) {
                activation = static_cast<GlobalContext *>(ctx)->global;
            }

            if (activation && (ctx->type == Type_QmlContext || activation->__hasProperty__(name))) {
                activation->put(name, value);
                return;
            }
        }
    }
    if (strictMode || name->isEqualTo(engine->id_this))
        throwReferenceError(Value::fromString(name));
    engine->globalObject->put(name, value);
}

Value ExecutionContext::getProperty(String *name)
{
    name->makeIdentifier();

    if (name->isEqualTo(engine->id_this))
        return thisObject;

    bool hasWith = false;
    bool hasCatchScope = false;
    for (ExecutionContext *ctx = this; ctx; ctx = ctx->outer) {
        if (ctx->type == Type_WithContext) {
            Object *w = static_cast<WithContext *>(ctx)->withObject;
            hasWith = true;
            bool hasProperty = false;
            Value v = w->get(name, &hasProperty);
            if (hasProperty) {
                return v;
            }
            continue;
        }

        else if (ctx->type == Type_CatchContext) {
            hasCatchScope = true;
            CatchContext *c = static_cast<CatchContext *>(ctx);
            if (c->exceptionVarName->isEqualTo(name))
                return c->exceptionValue;
        }

        else if (ctx->type >= Type_CallContext) {
            QV4::CallContext *c = static_cast<CallContext *>(ctx);
            FunctionObject *f = c->function;
            if (f->needsActivation || hasWith || hasCatchScope) {
                for (unsigned int i = 0; i < f->varCount; ++i)
                    if (f->varList[i]->isEqualTo(name))
                        return c->locals[i];
                for (int i = (int)f->formalParameterCount - 1; i >= 0; --i)
                    if (f->formalParameterList[i]->isEqualTo(name))
                        return c->arguments[i];
            }
            if (c->activation) {
                bool hasProperty = false;
                Value v = c->activation->get(name, &hasProperty);
                if (hasProperty)
                    return v;
            }
            if (f->function && f->function->isNamedExpression()
                && name->isEqualTo(f->function->name))
                return Value::fromObject(c->function);
        }

        else if (ctx->type == Type_GlobalContext) {
            GlobalContext *g = static_cast<GlobalContext *>(ctx);
            bool hasProperty = false;
            Value v = g->global->get(name, &hasProperty);
            if (hasProperty)
                return v;
        }
    }
    throwReferenceError(Value::fromString(name));
    return Value::undefinedValue();
}

Value ExecutionContext::getPropertyNoThrow(String *name)
{
    name->makeIdentifier();

    if (name->isEqualTo(engine->id_this))
        return thisObject;

    bool hasWith = false;
    bool hasCatchScope = false;
    for (ExecutionContext *ctx = this; ctx; ctx = ctx->outer) {
        if (ctx->type == Type_WithContext) {
            Object *w = static_cast<WithContext *>(ctx)->withObject;
            hasWith = true;
            bool hasProperty = false;
            Value v = w->get(name, &hasProperty);
            if (hasProperty) {
                return v;
            }
            continue;
        }

        else if (ctx->type == Type_CatchContext) {
            hasCatchScope = true;
            CatchContext *c = static_cast<CatchContext *>(ctx);
            if (c->exceptionVarName->isEqualTo(name))
                return c->exceptionValue;
        }

        else if (ctx->type >= Type_CallContext) {
            QV4::CallContext *c = static_cast<CallContext *>(ctx);
            FunctionObject *f = c->function;
            if (f->needsActivation || hasWith || hasCatchScope) {
                for (unsigned int i = 0; i < f->varCount; ++i)
                    if (f->varList[i]->isEqualTo(name))
                        return c->locals[i];
                for (int i = (int)f->formalParameterCount - 1; i >= 0; --i)
                    if (f->formalParameterList[i]->isEqualTo(name))
                        return c->arguments[i];
            }
            if (c->activation) {
                bool hasProperty = false;
                Value v = c->activation->get(name, &hasProperty);
                if (hasProperty)
                    return v;
            }
            if (f->function && f->function->isNamedExpression()
                && name->isEqualTo(f->function->name))
                return Value::fromObject(c->function);
        }

        else if (ctx->type == Type_GlobalContext) {
            GlobalContext *g = static_cast<GlobalContext *>(ctx);
            bool hasProperty = false;
            Value v = g->global->get(name, &hasProperty);
            if (hasProperty)
                return v;
        }
    }
    return Value::undefinedValue();
}

Value ExecutionContext::getPropertyAndBase(String *name, Object **base)
{
    *base = 0;
    name->makeIdentifier();

    if (name->isEqualTo(engine->id_this))
        return thisObject;

    bool hasWith = false;
    bool hasCatchScope = false;
    for (ExecutionContext *ctx = this; ctx; ctx = ctx->outer) {
        if (ctx->type == Type_WithContext) {
            Object *w = static_cast<WithContext *>(ctx)->withObject;
            hasWith = true;
            bool hasProperty = false;
            Value v = w->get(name, &hasProperty);
            if (hasProperty) {
                *base = w;
                return v;
            }
            continue;
        }

        else if (ctx->type == Type_CatchContext) {
            hasCatchScope = true;
            CatchContext *c = static_cast<CatchContext *>(ctx);
            if (c->exceptionVarName->isEqualTo(name))
                return c->exceptionValue;
        }

        else if (ctx->type >= Type_CallContext) {
            QV4::CallContext *c = static_cast<CallContext *>(ctx);
            FunctionObject *f = c->function;
            if (f->needsActivation || hasWith || hasCatchScope) {
                for (unsigned int i = 0; i < f->varCount; ++i)
                    if (f->varList[i]->isEqualTo(name))
                        return c->locals[i];
                for (int i = (int)f->formalParameterCount - 1; i >= 0; --i)
                    if (f->formalParameterList[i]->isEqualTo(name))
                        return c->arguments[i];
            }
            if (c->activation) {
                bool hasProperty = false;
                Value v = c->activation->get(name, &hasProperty);
                if (hasProperty) {
                    if (ctx->type == Type_QmlContext)
                        *base = c->activation;
                    return v;
                }
            }
            if (f->function && f->function->isNamedExpression()
                && name->isEqualTo(f->function->name))
                return Value::fromObject(c->function);
        }

        else if (ctx->type == Type_GlobalContext) {
            GlobalContext *g = static_cast<GlobalContext *>(ctx);
            bool hasProperty = false;
            Value v = g->global->get(name, &hasProperty);
            if (hasProperty)
                return v;
        }
    }
    throwReferenceError(Value::fromString(name));
    return Value::undefinedValue();
}



void ExecutionContext::inplaceBitOp(String *name, const Value &value, BinOp op)
{
    Value lhs = getProperty(name);
    Value result;
    op(&result, lhs, value);
    setProperty(name, result);
}

void ExecutionContext::throwError(const Value &value)
{
    __qmljs_throw(this, value);
}

void ExecutionContext::throwError(const QString &message)
{
    Value v = Value::fromString(this, message);
    throwError(Value::fromObject(engine->newErrorObject(v)));
}

void ExecutionContext::throwSyntaxError(const QString &message, const QString &fileName, int line, int column)
{
    Object *error = engine->newSyntaxErrorObject(message, fileName, line, column);
    throwError(Value::fromObject(error));
}

void ExecutionContext::throwSyntaxError(const QString &message)
{
    Object *error = engine->newSyntaxErrorObject(message);
    throwError(Value::fromObject(error));
}

void ExecutionContext::throwTypeError()
{
    throwError(Value::fromObject(engine->newTypeErrorObject(QStringLiteral("Type error"))));
}

void ExecutionContext::throwTypeError(const QString &message)
{
    throwError(Value::fromObject(engine->newTypeErrorObject(message)));
}

void ExecutionContext::throwUnimplemented(const QString &message)
{
    Value v = Value::fromString(this, QStringLiteral("Unimplemented ") + message);
    throwError(Value::fromObject(engine->newErrorObject(v)));
}

void ExecutionContext::throwReferenceError(Value value)
{
    String *s = value.toString(this);
    QString msg = s->toQString() + QStringLiteral(" is not defined");
    throwError(Value::fromObject(engine->newReferenceErrorObject(msg)));
}

void ExecutionContext::throwReferenceError(const QString &message, const QString &fileName, int line, int column)
{
    QString msg = message + QStringLiteral(" is not defined");
    throwError(Value::fromObject(engine->newReferenceErrorObject(msg, fileName, line, column)));
}

void ExecutionContext::throwRangeError(Value value)
{
    String *s = value.toString(this);
    QString msg = s->toQString() + QStringLiteral(" out of range");
    throwError(Value::fromObject(engine->newRangeErrorObject(msg)));
}

void ExecutionContext::throwURIError(Value msg)
{
    throwError(Value::fromObject(engine->newURIErrorObject(msg)));
}

void SimpleCallContext::initSimpleCallContext(ExecutionEngine *engine)
{
    initBaseContext(Type_SimpleCallContext, engine, engine->current);
    function = 0;
    arguments = 0;
    argumentCount = 0;
}