/**************************************************************************
**
** This file is part of Qt Creator
**
** Copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).
**
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** Commercial Usage
**
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** GNU Lesser General Public License Usage
**
** 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
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** If you are unsure which license is appropriate for your use, please
** contact the sales department at http://qt.nokia.com/contact.
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#ifndef QMLJS_INTERPRETER_H
#define QMLJS_INTERPRETER_H

#include <qmljs/qmljsdocument.h>
#include <qmljs/qmljs_global.h>
#include <qmljs/qmljscomponentversion.h>
#include <qmljs/parser/qmljsastfwd_p.h>

#include <QtCore/QFileInfoList>
#include <QtCore/QList>
#include <QtCore/QString>
#include <QtCore/QHash>
#include <QtCore/QSet>
#include <QtCore/QMutex>

namespace QmlJS {

class NameId;
class Document;

namespace Interpreter {

////////////////////////////////////////////////////////////////////////////////
// Forward declarations
////////////////////////////////////////////////////////////////////////////////
class Engine;
class Value;
class NullValue;
class UndefinedValue;
class NumberValue;
class BooleanValue;
class StringValue;
class ObjectValue;
class FunctionValue;
class Reference;
class ColorValue;
class AnchorLineValue;
class TypeEnvironment;

typedef QList<const Value *> ValueList;

class FakeMetaObject;
class FakeMetaMethod;
class FakeMetaProperty;
class FakeMetaEnum;

////////////////////////////////////////////////////////////////////////////////
// Value visitor
////////////////////////////////////////////////////////////////////////////////
class QMLJS_EXPORT ValueVisitor
{
public:
    ValueVisitor();
    virtual ~ValueVisitor();

    virtual void visit(const NullValue *);
    virtual void visit(const UndefinedValue *);
    virtual void visit(const NumberValue *);
    virtual void visit(const BooleanValue *);
    virtual void visit(const StringValue *);
    virtual void visit(const ObjectValue *);
    virtual void visit(const FunctionValue *);
    virtual void visit(const Reference *);
    virtual void visit(const ColorValue *);
    virtual void visit(const AnchorLineValue *);
};

////////////////////////////////////////////////////////////////////////////////
// QML/JS value
////////////////////////////////////////////////////////////////////////////////
class QMLJS_EXPORT Value
{
    Value(const Value &other);
    void operator = (const Value &other);

public:
    Value();
    virtual ~Value();

    virtual const NullValue *asNullValue() const;
    virtual const UndefinedValue *asUndefinedValue() const;
    virtual const NumberValue *asNumberValue() const;
    virtual const BooleanValue *asBooleanValue() const;
    virtual const StringValue *asStringValue() const;
    virtual const ObjectValue *asObjectValue() const;
    virtual const FunctionValue *asFunctionValue() const;
    virtual const Reference *asReference() const;
    virtual const ColorValue *asColorValue() const;
    virtual const AnchorLineValue *asAnchorLineValue() const;

    virtual void accept(ValueVisitor *) const = 0;

    virtual bool getSourceLocation(QString *fileName, int *line, int *column) const;
};

template <typename _RetTy> _RetTy value_cast(const Value *v);

template <> Q_INLINE_TEMPLATE const NullValue *value_cast(const Value *v)
{
    if (v) return v->asNullValue();
    else   return 0;
}

template <> Q_INLINE_TEMPLATE const UndefinedValue *value_cast(const Value *v)
{
    if (v) return v->asUndefinedValue();
    else   return 0;
}

template <> Q_INLINE_TEMPLATE const NumberValue *value_cast(const Value *v)
{
    if (v) return v->asNumberValue();
    else   return 0;
}

template <> Q_INLINE_TEMPLATE const BooleanValue *value_cast(const Value *v)
{
    if (v) return v->asBooleanValue();
    else   return 0;
}

template <> Q_INLINE_TEMPLATE const StringValue *value_cast(const Value *v)
{
    if (v) return v->asStringValue();
    else   return 0;
}

template <> Q_INLINE_TEMPLATE const ObjectValue *value_cast(const Value *v)
{
    if (v) return v->asObjectValue();
    else   return 0;
}

template <> Q_INLINE_TEMPLATE const FunctionValue *value_cast(const Value *v)
{
    if (v) return v->asFunctionValue();
    else   return 0;
}

template <> Q_INLINE_TEMPLATE const Reference *value_cast(const Value *v)
{
    if (v) return v->asReference();
    else   return 0;
}

template <> Q_INLINE_TEMPLATE const ColorValue *value_cast(const Value *v)
{
    if (v) return v->asColorValue();
    else   return 0;
}

template <> Q_INLINE_TEMPLATE const AnchorLineValue *value_cast(const Value *v)
{
    if (v) return v->asAnchorLineValue();
    else   return 0;
}

////////////////////////////////////////////////////////////////////////////////
// Value nodes
////////////////////////////////////////////////////////////////////////////////
class QMLJS_EXPORT NullValue: public Value
{
public:
    virtual const NullValue *asNullValue() const;
    virtual void accept(ValueVisitor *visitor) const;
};

class QMLJS_EXPORT UndefinedValue: public Value
{
public:
    virtual const UndefinedValue *asUndefinedValue() const;
    virtual void accept(ValueVisitor *visitor) const;
};

class QMLJS_EXPORT NumberValue: public Value
{
public:
    virtual const NumberValue *asNumberValue() const;
    virtual void accept(ValueVisitor *visitor) const;
};

class QMLJS_EXPORT BooleanValue: public Value
{
public:
    virtual const BooleanValue *asBooleanValue() const;
    virtual void accept(ValueVisitor *visitor) const;
};

class QMLJS_EXPORT StringValue: public Value
{
public:
    virtual const StringValue *asStringValue() const;
    virtual void accept(ValueVisitor *visitor) const;
};

class QMLJS_EXPORT MemberProcessor
{
    MemberProcessor(const MemberProcessor &other);
    void operator = (const MemberProcessor &other);

public:
    MemberProcessor();
    virtual ~MemberProcessor();

    // Returns false to stop the processor.
    virtual bool processProperty(const QString &name, const Value *value);
    virtual bool processEnumerator(const QString &name, const Value *value);
    virtual bool processSignal(const QString &name, const Value *value);
    virtual bool processSlot(const QString &name, const Value *value);
    virtual bool processGeneratedSlot(const QString &name, const Value *value);
};

class QMLJS_EXPORT ScopeChain
{
public:
    ScopeChain();

    class QMLJS_EXPORT QmlComponentChain
    {
        Q_DISABLE_COPY(QmlComponentChain)
    public:
        QmlComponentChain();
        ~QmlComponentChain();

        QList<const QmlComponentChain *> instantiatingComponents;
        Document::Ptr document;

        void collect(QList<const ObjectValue *> *list) const;
        void clear();
    };

    const ObjectValue *globalScope;
    QSharedPointer<const QmlComponentChain> qmlComponentScope;
    QList<const ObjectValue *> qmlScopeObjects;
    const TypeEnvironment *qmlTypes;
    QList<const ObjectValue *> jsScopes;

    // rebuilds the flat list of all scopes
    void update();
    QList<const ObjectValue *> all() const;

private:
    QList<const ObjectValue *> _all;
};

class QMLJS_EXPORT Context
{
public:
    Context();
    ~Context();

    Engine *engine() const;
    const ScopeChain &scopeChain() const;
    ScopeChain &scopeChain();

    const TypeEnvironment *typeEnvironment(const Document *doc) const;
    void setTypeEnvironment(const Document *doc, const TypeEnvironment *typeEnvironment);

    const Value *lookup(const QString &name, const ObjectValue **foundInScope = 0) const;
    const ObjectValue *lookupType(const Document *doc, AST::UiQualifiedId *qmlTypeName) const;
    const ObjectValue *lookupType(const Document *doc, const QStringList &qmlTypeName) const;
    const Value *lookupReference(const Reference *reference) const;

    const Value *property(const ObjectValue *object, const QString &name) const;
    void setProperty(const ObjectValue *object, const QString &name, const Value *value);

    QString defaultPropertyName(const ObjectValue *object) const;

private:
    typedef QHash<QString, const Value *> Properties;

    QSharedPointer<Engine> _engine;
    QHash<const ObjectValue *, Properties> _properties;
    QHash<QString, const TypeEnvironment *> _typeEnvironments;
    ScopeChain _scopeChain;
    int _qmlScopeObjectIndex;
    bool _qmlScopeObjectSet;

    // for avoiding reference cycles during lookup
    mutable QList<const Reference *> _referenceStack;
};

class QMLJS_EXPORT Reference: public Value
{
public:
    Reference(Engine *engine);
    virtual ~Reference();

    Engine *engine() const;

    // Value interface
    virtual const Reference *asReference() const;
    virtual void accept(ValueVisitor *) const;

private:
    virtual const Value *value(const Context *context) const;

    Engine *_engine;
    friend class Context;
};

class QMLJS_EXPORT ColorValue: public Value
{
public:
    // Value interface
    virtual const ColorValue *asColorValue() const;
    virtual void accept(ValueVisitor *) const;
};

class QMLJS_EXPORT AnchorLineValue: public Value
{
public:
    // Value interface
    virtual const AnchorLineValue *asAnchorLineValue() const;
    virtual void accept(ValueVisitor *) const;
};

class QMLJS_EXPORT ObjectValue: public Value
{
public:
    ObjectValue(Engine *engine);
    virtual ~ObjectValue();

    Engine *engine() const;

    QString className() const;
    void setClassName(const QString &className);

    const ObjectValue *prototype(const Context *context) const;
    void setPrototype(const Value *prototype);

    virtual void processMembers(MemberProcessor *processor) const;

    virtual const Value *property(const QString &name, const Context *context) const;
    virtual void setProperty(const QString &name, const Value *value);
    virtual void removeProperty(const QString &name);

    virtual const Value *lookupMember(const QString &name, const Context *context, bool examinePrototypes = true) const;

    // Value interface
    virtual const ObjectValue *asObjectValue() const;
    virtual void accept(ValueVisitor *visitor) const;

private:
    bool checkPrototype(const ObjectValue *prototype, QSet<const ObjectValue *> *processed) const;

private:
    Engine *_engine;
    const Value *_prototype;
    QHash<QString, const Value *> _members;
    QString _className;
};

class QMLJS_EXPORT QmlObjectValue: public ObjectValue
{
public:
    QmlObjectValue(const FakeMetaObject *metaObject, Engine *engine);
    virtual ~QmlObjectValue();

    virtual void processMembers(MemberProcessor *processor) const;
    const Value *propertyValue(const FakeMetaProperty &prop) const;

    QString packageName() const;
    ComponentVersion version() const;
    QString defaultPropertyName() const;
    QString propertyType(const QString &propertyName) const;
    bool isListProperty(const QString &name) const;
    bool isEnum(const QString &typeName) const;
    bool enumContainsKey(const QString &enumName, const QString &enumKeyName) const;
    bool hasChildInPackage() const;

protected:
    const Value *findOrCreateSignature(int index, const FakeMetaMethod &method, QString *methodName) const;
    bool isDerivedFrom(const FakeMetaObject *base) const;

private:
    const FakeMetaObject *_metaObject;
    mutable QHash<int, const Value *> _metaSignature;
};

class QMLJS_EXPORT QmlEnumValue: public NumberValue
{
public:
    QmlEnumValue(const FakeMetaEnum &metaEnum, Engine *engine);
    virtual ~QmlEnumValue();

    QString name() const;
    QStringList keys() const;

private:
    FakeMetaEnum *_metaEnum;
};

class QMLJS_EXPORT Activation
{
public:
    explicit Activation(Context *parentContext = 0);
    virtual ~Activation();

    Context *context() const;
    Context *parentContext() const;

    bool calledAsConstructor() const;
    void setCalledAsConstructor(bool calledAsConstructor);

    bool calledAsFunction() const;
    void setCalledAsFunction(bool calledAsFunction);

    ObjectValue *thisObject() const;
    void setThisObject(ObjectValue *thisObject);

    ValueList arguments() const;
    void setArguments(const ValueList &arguments);

private:
    ObjectValue *_thisObject;
    ValueList _arguments;
    bool _calledAsFunction;
    Context *_parentContext;
};


class QMLJS_EXPORT FunctionValue: public ObjectValue
{
public:
    FunctionValue(Engine *engine);
    virtual ~FunctionValue();

    // [[construct]]
    const Value *construct(const ValueList &actuals = ValueList()) const;

    // [[call]]
    const Value *call(const ValueList &actuals = ValueList()) const;

    const Value *call(const ObjectValue *thisObject,
                      const ValueList &actuals = ValueList()) const;


    virtual const Value *returnValue() const;

    virtual int argumentCount() const;
    virtual const Value *argument(int index) const;
    virtual QString argumentName(int index) const;
    virtual bool isVariadic() const;

    virtual const Value *invoke(const Activation *activation) const;

    // Value interface
    virtual const FunctionValue *asFunctionValue() const;
    virtual void accept(ValueVisitor *visitor) const;
};

class QMLJS_EXPORT Function: public FunctionValue
{
public:
    Function(Engine *engine);
    virtual ~Function();

    void addArgument(const Value *argument);
    void setReturnValue(const Value *returnValue);

    // ObjectValue interface
    virtual const Value *property(const QString &name, const Context *context) const;

    // FunctionValue interface
    virtual const Value *returnValue() const;
    virtual int argumentCount() const;
    virtual const Value *argument(int index) const;
    virtual const Value *invoke(const Activation *activation) const;

private:
    ValueList _arguments;
    const Value *_returnValue;
};


////////////////////////////////////////////////////////////////////////////////
// typing environment
////////////////////////////////////////////////////////////////////////////////

class QMLJS_EXPORT CppQmlTypesLoader
{
public:
    /** \return an empty list when successful, error messages otherwise. */
    static QStringList load(const QFileInfoList &xmlFiles);
    static QList<const FakeMetaObject *> builtinObjects;

    // parses the xml string and fills the newObjects map
    static QString parseQmlTypeXml(const QByteArray &xml, QMap<QString, FakeMetaObject *> *newObjects);
private:
    static void setSuperClasses(QMap<QString, FakeMetaObject *> *newObjects);
};

class QMLJS_EXPORT CppQmlTypes
{
public:
    void load(Interpreter::Engine *interpreter, const QList<const FakeMetaObject *> &objects);

    QList<Interpreter::QmlObjectValue *> typesForImport(const QString &prefix, ComponentVersion version) const;
    Interpreter::QmlObjectValue *typeForImport(const QString &qualifiedName) const;

    bool hasPackage(const QString &package) const;

    QHash<QString, QmlObjectValue *> types() const
    { return _typesByFullyQualifiedName; }

private:
    QHash<QString, QList<QmlObjectValue *> > _typesByPackage;
    QHash<QString, QmlObjectValue *> _typesByFullyQualifiedName;
};

class ConvertToNumber: protected ValueVisitor // ECMAScript ToInt()
{
public:
    ConvertToNumber(Engine *engine);

    const Value *operator()(const Value *value);

protected:
    const Value *switchResult(const Value *value);

    virtual void visit(const NullValue *);
    virtual void visit(const UndefinedValue *);
    virtual void visit(const NumberValue *);
    virtual void visit(const BooleanValue *);
    virtual void visit(const StringValue *);
    virtual void visit(const ObjectValue *);
    virtual void visit(const FunctionValue *);

private:
    Engine *_engine;
    const Value *_result;
};

class ConvertToString: protected ValueVisitor // ECMAScript ToString
{
public:
    ConvertToString(Engine *engine);

    const Value *operator()(const Value *value);

protected:
    const Value *switchResult(const Value *value);

    virtual void visit(const NullValue *);
    virtual void visit(const UndefinedValue *);
    virtual void visit(const NumberValue *);
    virtual void visit(const BooleanValue *);
    virtual void visit(const StringValue *);
    virtual void visit(const ObjectValue *);
    virtual void visit(const FunctionValue *);

private:
    Engine *_engine;
    const Value *_result;
};

class ConvertToObject: protected ValueVisitor // ECMAScript ToObject
{
public:
    ConvertToObject(Engine *engine);

    const Value *operator()(const Value *value);

protected:
    const Value *switchResult(const Value *value);

    virtual void visit(const NullValue *);
    virtual void visit(const UndefinedValue *);
    virtual void visit(const NumberValue *);
    virtual void visit(const BooleanValue *);
    virtual void visit(const StringValue *);
    virtual void visit(const ObjectValue *);
    virtual void visit(const FunctionValue *);

private:
    Engine *_engine;
    const Value *_result;
};

class TypeId: protected ValueVisitor
{
    QString _result;

public:
    QString operator()(const Value *value);

protected:
    virtual void visit(const NullValue *);
    virtual void visit(const UndefinedValue *);
    virtual void visit(const NumberValue *);
    virtual void visit(const BooleanValue *);
    virtual void visit(const StringValue *);
    virtual void visit(const ObjectValue *object);
    virtual void visit(const FunctionValue *object);
    virtual void visit(const ColorValue *);
    virtual void visit(const AnchorLineValue *);
};

class QMLJS_EXPORT Engine
{
    Q_DISABLE_COPY(Engine)

public:
    Engine();
    ~Engine();

    const NullValue *nullValue() const;
    const UndefinedValue *undefinedValue() const;
    const NumberValue *numberValue() const;
    const BooleanValue *booleanValue() const;
    const StringValue *stringValue() const;
    const ColorValue *colorValue() const;
    const AnchorLineValue *anchorLineValue() const;

    ObjectValue *newObject(const ObjectValue *prototype);
    ObjectValue *newObject();
    Function *newFunction();
    const Value *newArray(); // ### remove me

    // QML objects
    const ObjectValue *qmlKeysObject();
    const ObjectValue *qmlFontObject();
    const ObjectValue *qmlPointObject();
    const ObjectValue *qmlSizeObject();
    const ObjectValue *qmlRectObject();
    const ObjectValue *qmlVector3DObject();

    const Value *defaultValueForBuiltinType(const QString &typeName) const;

    // global object
    ObjectValue *globalObject() const;
    const ObjectValue *mathObject() const;
    const ObjectValue *qtObject() const;

    // prototypes
    ObjectValue *objectPrototype() const;
    ObjectValue *functionPrototype() const;
    ObjectValue *numberPrototype() const;
    ObjectValue *booleanPrototype() const;
    ObjectValue *stringPrototype() const;
    ObjectValue *arrayPrototype() const;
    ObjectValue *datePrototype() const;
    ObjectValue *regexpPrototype() const;

    // ctors
    const FunctionValue *objectCtor() const;
    const FunctionValue *functionCtor() const;
    const FunctionValue *arrayCtor() const;
    const FunctionValue *stringCtor() const;
    const FunctionValue *booleanCtor() const;
    const FunctionValue *numberCtor() const;
    const FunctionValue *dateCtor() const;
    const FunctionValue *regexpCtor() const;

    // operators
    const Value *convertToBoolean(const Value *value);
    const Value *convertToNumber(const Value *value);
    const Value *convertToString(const Value *value);
    const Value *convertToObject(const Value *value);
    QString typeId(const Value *value);

    // typing:
    CppQmlTypes &cppQmlTypes()
    { return _cppQmlTypes; }
    const CppQmlTypes &cppQmlTypes() const
    { return _cppQmlTypes; }

    void registerValue(Value *value); // internal

private:
    void initializePrototypes();

    void addFunction(ObjectValue *object, const QString &name, const Value *result, int argumentCount);
    void addFunction(ObjectValue *object, const QString &name, int argumentCount);

private:
    ObjectValue *_objectPrototype;
    ObjectValue *_functionPrototype;
    ObjectValue *_numberPrototype;
    ObjectValue *_booleanPrototype;
    ObjectValue *_stringPrototype;
    ObjectValue *_arrayPrototype;
    ObjectValue *_datePrototype;
    ObjectValue *_regexpPrototype;

    Function *_objectCtor;
    Function *_functionCtor;
    Function *_arrayCtor;
    Function *_stringCtor;
    Function *_booleanCtor;
    Function *_numberCtor;
    Function *_dateCtor;
    Function *_regexpCtor;

    ObjectValue *_globalObject;
    ObjectValue *_mathObject;
    ObjectValue *_qtObject;
    ObjectValue *_qmlKeysObject;
    ObjectValue *_qmlFontObject;
    ObjectValue *_qmlPointObject;
    ObjectValue *_qmlSizeObject;
    ObjectValue *_qmlRectObject;
    ObjectValue *_qmlVector3DObject;

    NullValue _nullValue;
    UndefinedValue _undefinedValue;
    NumberValue _numberValue;
    BooleanValue _booleanValue;
    StringValue _stringValue;
    ColorValue _colorValue;
    AnchorLineValue _anchorLineValue;
    QList<Value *> _registeredValues;

    ConvertToNumber _convertToNumber;
    ConvertToString _convertToString;
    ConvertToObject _convertToObject;
    TypeId _typeId;

    CppQmlTypes _cppQmlTypes;

    QMutex _mutex;
};


// internal
class QMLJS_EXPORT QmlPrototypeReference: public Reference
{
public:
    QmlPrototypeReference(AST::UiQualifiedId *qmlTypeName, const Document *doc, Engine *engine);
    virtual ~QmlPrototypeReference();

    AST::UiQualifiedId *qmlTypeName() const;

private:    
    virtual const Value *value(const Context *context) const;

    AST::UiQualifiedId *_qmlTypeName;
    const Document *_doc;
};

class QMLJS_EXPORT ASTVariableReference: public Reference
{
    AST::VariableDeclaration *_ast;

public:
    ASTVariableReference(AST::VariableDeclaration *ast, Engine *engine);
    virtual ~ASTVariableReference();

private:
    virtual const Value *value(const Context *context) const;
};

class QMLJS_EXPORT ASTFunctionValue: public FunctionValue
{
    AST::FunctionDeclaration *_ast;
    const Document *_doc;
    QList<NameId *> _argumentNames;

public:
    ASTFunctionValue(AST::FunctionDeclaration *ast, const Document *doc, Engine *engine);
    virtual ~ASTFunctionValue();

    AST::FunctionDeclaration *ast() const;

    virtual const Value *returnValue() const;
    virtual int argumentCount() const;
    virtual const Value *argument(int) const;
    virtual QString argumentName(int index) const;
    virtual bool isVariadic() const;

    virtual bool getSourceLocation(QString *fileName, int *line, int *column) const;
};

class QMLJS_EXPORT ASTPropertyReference: public Reference
{
    AST::UiPublicMember *_ast;
    const Document *_doc;
    QString _onChangedSlotName;

public:
    ASTPropertyReference(AST::UiPublicMember *ast, const Document *doc, Engine *engine);
    virtual ~ASTPropertyReference();

    AST::UiPublicMember *ast() const { return _ast; }
    QString onChangedSlotName() const { return _onChangedSlotName; }

    virtual bool getSourceLocation(QString *fileName, int *line, int *column) const;

private:
    virtual const Value *value(const Context *context) const;
};

class QMLJS_EXPORT ASTSignalReference: public Reference
{
    AST::UiPublicMember *_ast;
    const Document *_doc;
    QString _slotName;

public:
    ASTSignalReference(AST::UiPublicMember *ast, const Document *doc, Engine *engine);
    virtual ~ASTSignalReference();

    AST::UiPublicMember *ast() const { return _ast; }
    QString slotName() const { return _slotName; }

    virtual bool getSourceLocation(QString *fileName, int *line, int *column) const;

private:
    virtual const Value *value(const Context *context) const;
};

class QMLJS_EXPORT ASTObjectValue: public ObjectValue
{
    AST::UiQualifiedId *_typeName;
    AST::UiObjectInitializer *_initializer;
    const Document *_doc;
    QList<ASTPropertyReference *> _properties;
    QList<ASTSignalReference *> _signals;
    ASTPropertyReference *_defaultPropertyRef;

public:
    ASTObjectValue(AST::UiQualifiedId *typeName,
                   AST::UiObjectInitializer *initializer,
                   const Document *doc,
                   Engine *engine);
    virtual ~ASTObjectValue();

    bool getSourceLocation(QString *fileName, int *line, int *column) const;
    virtual void processMembers(MemberProcessor *processor) const;

    QString defaultPropertyName() const;
};

class QMLJS_EXPORT ImportInfo
{
public:
    enum Type {
        InvalidImport,
        ImplicitDirectoryImport,
        LibraryImport,
        FileImport,
        DirectoryImport,
        UnknownFileImport // refers a file/directoy that wasn't found
    };

    ImportInfo();
    ImportInfo(Type type, const QString &name,
               ComponentVersion version = ComponentVersion(),
               AST::UiImport *ast = 0);

    bool isValid() const;
    Type type() const;

    // LibraryImport: uri with '/' separator
    // Other: absoluteFilePath
    QString name() const;

    // null if the import has no 'as', otherwise the target id
    QString id() const;

    ComponentVersion version() const;
    AST::UiImport *ast() const;

private:
    Type _type;
    QString _name;
    ComponentVersion _version;
    AST::UiImport *_ast;
};

class QMLJS_EXPORT TypeEnvironment: public ObjectValue
{
    QHash<const ObjectValue *, ImportInfo> _imports;

public:
    TypeEnvironment(Engine *engine);

    virtual const Value *lookupMember(const QString &name, const Context *context, bool examinePrototypes) const;
    virtual void processMembers(MemberProcessor *processor) const;

    void addImport(const ObjectValue *import, const ImportInfo &info);
    ImportInfo importInfo(const QString &name, const Context *context) const;
};

} } // end of namespace QmlJS::Interpreter

#endif // QMLJS_INTERPRETER_H