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#ifndef GENERATOR_H
#define GENERATOR_H

#include <abstractmetalang_typedefs.h>
#include <typedatabase_typedefs.h>
#include <dependency.h>
#include <QtCore/QObject>
#include <QtCore/QSharedPointer>
#include <QtCore/QTextStream>
#include <QtCore/QVector>

class ApiExtractor;
class AbstractMetaBuilder;
class AbstractMetaFunction;
class AbstractMetaClass;
class AbstractMetaEnum;
class TypeEntry;
class ComplexTypeEntry;
class AbstractMetaType;
class EnumTypeEntry;
class FlagsTypeEntry;

QT_BEGIN_NAMESPACE
class QFile;
QT_END_NAMESPACE

class PrimitiveTypeEntry;
class ContainerTypeEntry;
class Indentor;

QTextStream& formatCode(QTextStream &s, const QString& code, Indentor &indentor);
void verifyDirectoryFor(const QFile &file);

QString getClassTargetFullName(const AbstractMetaClass* metaClass, bool includePackageName = true);
QString getClassTargetFullName(const AbstractMetaEnum* metaEnum, bool includePackageName = true);
QString getClassTargetFullName(const AbstractMetaType *metaType, bool includePackageName = true);
QString getFilteredCppSignatureString(QString signature);

/**
 * PYSIDE-504: Handling the "protected hack"
 *
 * The problem: Creating wrappers when the class has private destructors.
 * You can see an example on Windows in qclipboard_wrapper.h and others.
 * Simply search for the text "// C++11: need to declare (unimplemented) destructor".
 *
 * The protected hack is the definition "#define protected public".
 * For most compilers, this "hack" is enabled, because the problem of private
 * destructors simply vanishes.
 *
 * If one does not want to use this hack, then a new problem arises:
 * C++11 requires that a destructor is declared in a wrapper class when it is
 * private in the base class. There is no implementation allowed!
 *
 * Unfortunately, MSVC in recent versions supports C++11, and due to restrictive
 * rules, it is impossible to use the hack with this compiler.
 * More unfortunate: Clang, when C++11 is enabled, also enforces a declaration
 * of a private destructor, but it falsely then creates a linker error!
 *
 * Originally, we wanted to remove the protected hack. But due to the Clang
 * problem, we gave up on removal of the protected hack and use it always
 * when we can. This might change again when the Clang problem is solved.
 */

#ifdef Q_CC_MSVC
const int alwaysGenerateDestructor = 1;
#else
const int alwaysGenerateDestructor = 0;
#endif

/**
 * A GeneratorContext object contains a pointer to an AbstractMetaClass and/or a specialized
 * AbstractMetaType, for which code is currently being generated.
 *
 * The main case is when the context contains only an AbstractMetaClass pointer, which is used
 * by different methods to generate appropriate expressions, functions, type names, etc.
 *
 * The second case is for generation of code for smart pointers. In this case the m_metaClass member
 * contains the generic template class of the smart pointer, and the m_preciseClassType member
 * contains the instantiated template type, e.g. a concrete shared_ptr<int>. To
 * distinguish this case, the member m_forSmartPointer is set to true.
 *
 * In the future the second case might be generalized for all template type instantiations.
 */
class GeneratorContext {
public:
    GeneratorContext() : m_metaClass(0), m_preciseClassType(0), m_forSmartPointer(false) {}
    GeneratorContext(AbstractMetaClass *metaClass,
                     const AbstractMetaType *preciseType = 0,
                     bool forSmartPointer = false)
        : m_metaClass(metaClass),
        m_preciseClassType(preciseType),
        m_forSmartPointer(forSmartPointer) {}


    AbstractMetaClass *metaClass() const { return m_metaClass; }
    bool forSmartPointer() const { return m_forSmartPointer; }
    const AbstractMetaType *preciseType() const { return m_preciseClassType; }

private:
    AbstractMetaClass *m_metaClass;
    const AbstractMetaType *m_preciseClassType;
    bool m_forSmartPointer;
};

/**
 *   Base class for all generators. The default implementations does nothing,
 *   you must subclass this to create your own generators.
 */
class Generator
{
public:
    typedef QPair<QString, QString> OptionDescription;
    typedef QVector<OptionDescription> OptionDescriptions;

    /// Optiosn used around the generator code
    enum Option {
        NoOption                 = 0x00000000,
        ExcludeConst             = 0x00000001,
        ExcludeReference         = 0x00000002,

        EnumAsInts               = 0x00000004,
        SkipName                 = 0x00000008,
        SkipReturnType           = 0x00000010,
        OriginalName             = 0x00000020,
        VirtualCall              = 0x00000040,
        OriginalTypeDescription  = 0x00000080,
        SkipRemovedArguments     = 0x00000100,

        SkipDefaultValues        = 0x00000200,

        WriteSelf                = 0x00000400,
        ExcludeMethodConst       = 0x00000800,

        ForceValueType           = ExcludeReference | ExcludeConst
    };
    Q_DECLARE_FLAGS(Options, Option)

    Generator();
    virtual ~Generator();

    bool setup(const ApiExtractor& extractor, const QMap<QString, QString> args);

    virtual OptionDescriptions options() const;

    /// Returns the classes used to generate the binding code.
    AbstractMetaClassList classes() const;

    /// Returns the classes, topologically ordered, used to generate the binding code.
    ///
    /// The classes are ordered such that derived classes appear later in the list than
    /// their parent classes.
    AbstractMetaClassList classesTopologicalSorted(const Dependencies &additionalDependencies = Dependencies()) const;

    /// Returns all global functions found by APIExtractor
    AbstractMetaFunctionList globalFunctions() const;

    /// Returns all global enums found by APIExtractor
    AbstractMetaEnumList globalEnums() const;

    /// Returns all primitive types found by APIExtractor
    PrimitiveTypeEntryList primitiveTypes() const;

    /// Returns all container types found by APIExtractor
    ContainerTypeEntryList containerTypes() const;

    /// Returns an AbstractMetaEnum for a given EnumTypeEntry, or NULL if not found.
    const AbstractMetaEnum* findAbstractMetaEnum(const EnumTypeEntry* typeEntry) const;

    /// Returns an AbstractMetaEnum for a given TypeEntry that is an EnumTypeEntry, or NULL if not found.
    const AbstractMetaEnum* findAbstractMetaEnum(const TypeEntry* typeEntry) const;

    /// Returns an AbstractMetaEnum for the enum related to a given FlagsTypeEntry, or NULL if not found.
    const AbstractMetaEnum* findAbstractMetaEnum(const FlagsTypeEntry* typeEntry) const;

    /// Returns an AbstractMetaEnum for a given AbstractMetaType that holds an EnumTypeEntry, or NULL if not found.
    const AbstractMetaEnum* findAbstractMetaEnum(const AbstractMetaType* metaType) const;

    /// Returns the output directory
    QString outputDirectory() const;

    /// Set the output directory
    void setOutputDirectory(const QString &outDir);

    /**
    *   Start the code generation, be sure to call setClasses before callign this method.
    *   For each class it creates a QTextStream, call the write method with the current
    *   class and the associated text stream, then write the text stream contents if needed.
    *   \see #write
    */
    bool generate();


    /// Generates a file for given AbstractMetaClass or AbstractMetaType (smart pointer case).
    bool generateFileForContext(GeneratorContext &context);

    /// Returns the file base name for a smart pointer.
    QString getFileNameBaseForSmartPointer(const AbstractMetaType *smartPointerType,
                                           const AbstractMetaClass *smartPointerClass) const;

    /// Returns the generator's name. Used for cosmetic purposes.
    virtual const char* name() const = 0;

    /// Returns true if the generator should generate any code for the TypeEntry.
    bool shouldGenerateTypeEntry(const TypeEntry*) const;

    /// Returns true if the generator should generate any code for the AbstractMetaClass.
    virtual bool shouldGenerate(const AbstractMetaClass *) const;

    /// Returns the subdirectory used to write the binding code of an AbstractMetaClass.
    virtual QString subDirectoryForClass(const AbstractMetaClass* clazz) const;

    /**
    *   Translate metatypes to binding source format.
    *   \param metatype a pointer to metatype
    *   \param context the current meta class
    *   \param option some extra options
    *   \return the metatype translated to binding source format
    */
    QString translateType(const AbstractMetaType *metatype,
                          const AbstractMetaClass *context,
                          Options options = NoOption) const;

    /**
    *   Function used to write the fucntion arguments on the class buffer.
    *   \param s the class output buffer
    *   \param metafunction the pointer to metafunction information
    *   \param count the number of function arguments
    *   \param options some extra options used during the parser
    */
    virtual void writeFunctionArguments(QTextStream &s,
                                        const AbstractMetaFunction *metafunction,
                                        Options options = NoOption) const = 0;

    virtual void writeArgumentNames(QTextStream &s,
                                    const AbstractMetaFunction *metafunction,
                                    Options options = NoOption) const = 0;

    void replaceTemplateVariables(QString &code, const AbstractMetaFunction *func);

    /**
    *   Returns the license comment to be prepended to each source file generated.
    */
    QString licenseComment() const;

    /**
    *   Sets the license comment to be prepended to each source file generated.
    */
    void setLicenseComment(const QString &licenseComment);

    /**
     *   Returns the package name.
     */
    QString packageName() const;

    /**
     *  Retrieves the name of the currently processed module.
     *  While package name is a complete package idetification, e.g. 'PySide.QtCore',
     *  a module name represents the last part of the package, e.g. 'QtCore'.
     *  If the target language separates the modules with characters other than
     *  dots ('.') the generator subclass must overload this method.
     *  \return a string representing the last part of a package name
     */
    virtual QString moduleName() const;

    /**
     *   Retrieves a list of constructors used in implicit conversions
     *   available on the given type. The TypeEntry must be a value-type
     *   or else it will return an empty list.
     *   \param type a TypeEntry that is expected to be a value-type
     *   \return a list of constructors that could be used as implicit converters
     */
    AbstractMetaFunctionList implicitConversions(const TypeEntry* type) const;

    /// Convenience function for implicitConversions(const TypeEntry* type).
    AbstractMetaFunctionList implicitConversions(const AbstractMetaType* metaType) const;

    /// Check if type is a pointer.
    static bool isPointer(const AbstractMetaType* type);

    /// Tells if the type or class is an Object (or QObject) Type.
    static bool isObjectType(const TypeEntry* type);
    static bool isObjectType(const ComplexTypeEntry* type);
    static bool isObjectType(const AbstractMetaType* metaType);
    static bool isObjectType(const AbstractMetaClass* metaClass);

    /// Returns true if the type is a C string (const char*).
    static bool isCString(const AbstractMetaType* type);
    /// Returns true if the type is a void pointer.
    static bool isVoidPointer(const AbstractMetaType* type);

    // Returns the full name of the type.
    QString getFullTypeName(const TypeEntry* type) const;
    QString getFullTypeName(const AbstractMetaType* type) const;
    QString getFullTypeName(const AbstractMetaClass* metaClass) const;

    /**
     *  Returns the full qualified C++ name for an AbstractMetaType, but removing modifiers
     *  as 'const', '&', and '*' (except if the class is not derived from a template).
     *  This is useful for instantiated templates.
     */
    QString getFullTypeNameWithoutModifiers(const AbstractMetaType* type) const;

    /**
     *   Tries to build a minimal constructor for the type.
     *   It will check first for a user defined default constructor.
     *   Returns a null string if it fails.
     */
    QString minimalConstructor(const TypeEntry* type) const;
    QString minimalConstructor(const AbstractMetaType* type) const;
    QString minimalConstructor(const AbstractMetaClass* metaClass) const;

protected:
    /**
     *   Returns the file name used to write the binding code of an AbstractMetaClass/Type.
     *   \param context the GeneratorContext which contains an AbstractMetaClass or AbstractMetaType
     *   for which the file name must be returned
     *   \return the file name used to write the binding code for the class
     */
    virtual QString fileNameSuffix() const = 0;
    virtual QString fileNameForContext(GeneratorContext &context) const = 0;


    virtual bool doSetup(const QMap<QString, QString>& args) = 0;

    /**
     *   Write the bindding code for an AbstractMetaClass.
     *   This is called by generate method.
     *   \param  s   text stream to write the generated output
     *   \param  metaClass  the class that should be generated
     */
    virtual void generateClass(QTextStream& s, GeneratorContext &classContext) = 0;
    virtual bool finishGeneration() = 0;

    /**
    *    Returns the subdirectory path for a given package
    *    (aka module, aka library) name.
    *    If the target language separates the package modules with characters other
    *    than dots ('.') the generator subclass must overload this method.
    *    /param packageName complete package name for which to return the subdirectory path
    *    or nothing the use the name of the currently processed package
    *    /return a string representing the subdirectory path for the given package
    */
    virtual QString subDirectoryForPackage(QString packageName = QString()) const;

    QVector<const AbstractMetaType*> instantiatedContainers() const;
    QVector<const AbstractMetaType*> instantiatedSmartPointers() const;

    static QString getSimplifiedContainerTypeName(const AbstractMetaType *type);
    void addInstantiatedContainersAndSmartPointers(const AbstractMetaType *type,
                                                   const QString &context);

private:
    struct GeneratorPrivate;
    GeneratorPrivate* m_d;
    void collectInstantiatedContainersAndSmartPointers(const AbstractMetaFunction* func);
    void collectInstantiatedContainersAndSmartPointers(const AbstractMetaClass *metaClass);
    void collectInstantiatedContainersAndSmartPointers();
};

Q_DECLARE_OPERATORS_FOR_FLAGS(Generator::Options)
typedef QSharedPointer<Generator> GeneratorPtr;
typedef QVector<GeneratorPtr> Generators;

/**
* Utility class to store the identation level, use it in a QTextStream.
*/
class Indentor
{
public:
    Indentor() : indent(0) {}
    int indent;
};

/**
*   Class that use the RAII idiom to set and unset the identation level.
*/
class Indentation
{
public:
    Indentation(Indentor &indentor) : indentor(indentor)
    {
        indentor.indent++;
    }
    ~Indentation()
    {
        indentor.indent--;
    }

private:
    Indentor &indentor;
};

inline QTextStream &operator <<(QTextStream &s, const Indentor &indentor)
{
    for (int i = 0; i < indentor.indent; ++i)
        s << "    ";
    return s;
}

#endif // GENERATOR_H