// Copyright (C) 2020 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
// Qt-Security score:significant

#ifndef QQMLJSIMPORTER_P_H
#define QQMLJSIMPORTER_P_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 <qtqmlcompilerexports.h>

#include "qqmljscontextualtypes_p.h"
#include "qqmljsscope_p.h"
#include "qqmljsresourcefilemapper_p.h"
#include <QtQml/private/qqmldirparser_p.h>
#include <QtQml/private/qqmljsast_p.h>

#include <QtCore/qtyperevision.h>

QT_BEGIN_NAMESPACE

namespace QQmlJS {
class Import
{
public:
    Import() = default;
    Import(QString prefix, QString name, QTypeRevision version, bool isFile, bool isDependency);

    bool isValid() const;

    QString prefix() const { return m_prefix; }
    QString name() const { return m_name; }
    QTypeRevision version() const { return m_version; }
    bool isFile() const { return m_isFile; }
    bool isDependency() const { return m_isDependency; }

private:
    QString m_prefix;
    QString m_name;
    QTypeRevision m_version;
    bool m_isFile = false;
    bool m_isDependency = false;

    friend inline size_t qHash(const Import &key, size_t seed = 0) noexcept
    {
        return qHashMulti(seed, key.m_prefix, key.m_name, key.m_version,
                          key.m_isFile, key.m_isDependency);
    }

    friend inline bool operator==(const Import &a, const Import &b)
    {
        return a.m_prefix == b.m_prefix && a.m_name == b.m_name && a.m_version == b.m_version
                && a.m_isFile == b.m_isFile && a.m_isDependency == b.m_isDependency;
    }
};
}

enum QQmlJSImporterFlag {
    UseOptionalImports = 0x1,
    PreferQmlFilesFromSourceFolder = 0x2,
    TolerateFileSelectors = 0x4, // if we find a type "twice", check if one looks like it's from a file selector and use the other
};
Q_DECLARE_FLAGS(QQmlJSImporterFlags, QQmlJSImporterFlag)

class QQmlJSImportVisitor;
class QQmlJSLogger;
class Q_QMLCOMPILER_EXPORT QQmlJSImporter
{
    // In the list of QML types we prefix unresolvable QML names with $anonymous$, and C++
    // names with $internal$. This is to avoid clashes between them.
    // In the list of C++ types we insert types that don't have a C++ name as their
    // QML name prefixed with $anonymous$.
    static inline constexpr QLatin1String anonPrefix = QLatin1String("$anonymous$");
    static inline constexpr QLatin1String internalPrefix = QLatin1String("$internal$");
    static inline constexpr QLatin1String modulePrefix = QLatin1String("$module$");

public:
    static inline constexpr QLatin1String s_inProcessMarker = QLatin1String("$InProcess$");

    struct ImportedTypes {
        ImportedTypes(QQmlJS::ContextualTypes &&types, QList<QQmlJS::DiagnosticMessage> &&warnings)
            : m_types(std::move(types)), m_warnings(std::move(warnings))
        {}

        ImportedTypes(const ImportedTypes &) = default;
        ImportedTypes(ImportedTypes &&) = default;
        ImportedTypes &operator=(const ImportedTypes &) = default;
        ImportedTypes &operator=(ImportedTypes &&) = default;
        ~ImportedTypes() = default;

        void clear()
        {
            m_types.clearTypes();
            m_warnings.clear();
        }

        const QQmlJS::ContextualTypes &contextualTypes() const { return m_types; }
        const QList<QQmlJS::DiagnosticMessage> &warnings() const { return m_warnings; };

        bool isEmpty() const { return m_types.types().isEmpty(); }

        bool hasType(const QString &name) const { return m_types.hasType(name); }
        QQmlJS::ImportedScope<QQmlJSScope::ConstPtr> type(const QString &name) const
        {
            return m_types.type(name);
        }
        QString name(const QQmlJSScope::ConstPtr &type) const { return m_types.name(type); }
        void setType(const QString &name, const QQmlJS::ContextualType &type)
        {
            m_types.setType(name, type);
        }
        bool isNullType(const QString &name) const { return m_types.isNullType(name); }
        const QHash<QString, QQmlJS::ContextualType> &types() const { return m_types.types(); }
        const auto &names() const { return m_types.names(); }

        void add(ImportedTypes &&other)
        {
            m_types.addTypes(std::move(other.m_types));
            m_warnings.append(std::move(other.m_warnings));
        }

        void addWarnings(QList<QQmlJS::DiagnosticMessage> &&warnings)
        {
            m_warnings.append(std::move(warnings));
        }

    private:
        QQmlJS::ContextualTypes m_types;
        QList<QQmlJS::DiagnosticMessage> m_warnings;
    };

    QQmlJSImporter(const QStringList &importPaths, QQmlJSResourceFileMapper *mapper,
                   QQmlJSImporterFlags flags = QQmlJSImporterFlags{});

    QQmlJSResourceFileMapper *resourceFileMapper() const { return m_mapper; }
    void setResourceFileMapper(QQmlJSResourceFileMapper *mapper) { m_mapper = mapper; }

    QQmlJSResourceFileMapper *metaDataMapper() const { return m_metaDataMapper; }
    void setMetaDataMapper(QQmlJSResourceFileMapper *mapper) { m_metaDataMapper = mapper; }

    ImportedTypes importHardCodedBuiltins();
    QList<QQmlJS::DiagnosticMessage> importQmldirs(const QStringList &qmltypesFiles);

    QQmlJSScope::Ptr importFile(const QString &file);
    ImportedTypes importDirectory(const QString &directory, quint8 precedence,
                                  const QString &prefix = QString());

    // ### qmltc needs this. once re-written, we no longer need to expose this
    QHash<QString, QQmlJSScope::Ptr> importedFiles() const { return m_importedFiles; }

    ImportedTypes importModule(const QString &module, quint8 precedence,
                               const QString &prefix = QString(),
                               QTypeRevision version = QTypeRevision(),
                               QStringList *staticModuleList = nullptr);

    ImportedTypes builtinInternalNames();

    QList<QQmlJS::DiagnosticMessage> takeGlobalWarnings()
    {
        const auto result = std::move(m_globalWarnings);
        m_globalWarnings.clear();
        return result;
    }

    QStringList importPaths() const { return m_importPaths; }
    void setImportPaths(const QStringList &importPaths);

    void clearCache();

    QQmlJSScope::ConstPtr jsGlobalObject();
    QString pathOfModule(const QString &moduleName, QTypeRevision revision) const
    {
        const auto it = m_seenImports.constFind({ moduleName, revision });
        return it != m_seenImports.constEnd() ? *it : QString();
    }

    struct ImportVisitorPrerequisites
    {
        ImportVisitorPrerequisites(QQmlJSScope::Ptr target, QQmlJSLogger *logger,
                                   const QString &implicitImportDirectory = {},
                                   const QStringList &qmldirFiles = {})
            : m_target(target),
              m_logger(logger),
              m_implicitImportDirectory(implicitImportDirectory),
              m_qmldirFiles(qmldirFiles)
        {
            Q_ASSERT(target && logger);
        }

        QQmlJSScope::Ptr m_target;
        QQmlJSLogger *m_logger;
        QString m_implicitImportDirectory;
        QStringList m_qmldirFiles;
    };
    void runImportVisitor(QQmlJS::AST::Node *rootNode,
                          const ImportVisitorPrerequisites &prerequisites);

    /*!
    \internal
     When a qml file gets lazily loaded, it will be lexed and parsed and finally be constructed
    via an ImportVisitor. By default, this is done via the QQmlJSImportVisitor, but can also be done
    via other import visitors like QmltcVisitor, which is used by qmltc to compile a QML file, or
    QQmlDomAstCreatorWithQQmlJSScope, which is used to construct the Dom of lazily loaded QML files.
    */
    using ImportVisitor = std::function<void(QQmlJS::AST::Node *rootNode, QQmlJSImporter *self,
                                             const ImportVisitorPrerequisites &prerequisites)>;

    void setImportVisitor(ImportVisitor visitor) { m_importVisitor = visitor; }
    void setFlags(const QQmlJSImporterFlags &flags) { m_flags = flags; }
    QQmlJSImporterFlags flags() const { return m_flags; }

private:
    struct AvailableTypes
    {
        AvailableTypes(QQmlJS::ContextualTypes builtins)
            : cppNames(std::move(builtins))
            , qmlNames(QQmlJS::ContextualTypes::QML, {}, {}, cppNames.arrayType())
        {
        }

        // C++ names used in qmltypes files for non-composite types
        QQmlJS::ContextualTypes cppNames;

        // Names the importing component sees, including any prefixes
        QQmlJS::ContextualTypes qmlNames;

        // Static modules included here
        QStringList staticModules;

        // Warnings produced when importing
        QList<QQmlJS::DiagnosticMessage> warnings;

        // Whether a system module has been imported
        bool hasSystemModule = false;
    };

    struct Import {
        enum Type : bool { Directory, Qmldir };

        QString name;
        bool isStaticModule = false;
        bool isSystemModule = false;
        Type type = Directory;

        QList<QQmlJSExportedScope> objects;
        QHash<QString, QQmlJSExportedScope> scripts;
        QList<QQmlDirParser::Import> imports;
        QList<QQmlDirParser::Import> dependencies;

        // Warnings produced when importing
        QList<QQmlJS::DiagnosticMessage> warnings;
    };

    AvailableTypes builtinImportHelper();
    bool importHelper(const QString &module, AvailableTypes *types, quint8 precedence,
                      const QString &prefix = QString(), QTypeRevision version = QTypeRevision(),
                      bool isDependency = false, bool isFile = false);
    void processImport(const QQmlJS::Import &importDescription, const Import &import,
                       quint8 precedence, AvailableTypes *types);
    static void insertAliases(const QQmlJS::ContextualType &type,
                              QQmlJSImporter::AvailableTypes *types);
    void insertExport(const QQmlJS::ContextualType &type, const QQmlJS::Export &valExport,
                      const QString &qmlName,
                      QHash<QString, QList<QQmlJSScope::Export>> *seenExports,
                      QQmlJSImporter::AvailableTypes *types) const;
    QQmlJSScope::Export
    resolveConflictingExports(const QQmlJS::Import &importDescription,
                              const QQmlJSExportedScope &val, quint8 precedence,
                              QHash<QString, QList<QQmlJSScope::Export>> *seenExports,
                              QQmlJSImporter::AvailableTypes *types);
    enum SeenVersion { LowerVersion, SameVersion, HigherVersion };
    void insertExportWithConflictingVersion(const QQmlJSExportedScope &val, quint8 precedence,
                                            const QString &qmlName,
                                            const QQmlJSScope::Export &valExport,
                                            const QQmlJSScope::ConstPtr &scope,
                                            QHash<QString, QList<QQmlJSScope::Export>> *seenExports,
                                            QQmlJSImporter::AvailableTypes *types,
                                            SeenVersion seenVersion) const;
    SeenVersion computeSeenVersion(const QQmlJS::Import &importDescription,
                                   const QList<QQmlJS::Export> &existingExports,
                                   QTypeRevision valExportVersion) const;
    void insertExports(const QQmlJS::Import &importDescription, const QQmlJSExportedScope &val,
                       const QString &cppName, quint8 precedence,
                       QHash<QString, QList<QQmlJSScope::Export>> *seenExports,
                       QQmlJSImporter::AvailableTypes *types);
    void importDependencies(const Import &import, quint8 precedence, AvailableTypes *types,
                            const QString &prefix = QString(),
                            QTypeRevision version = QTypeRevision(), bool isDependency = false);
    QQmlDirParser createQmldirParserForFile(const QString &filename, Import *import);
    void readQmltypes(const QString &filename, Import *result);
    Import readQmldir(const QString &dirname);
    Import readDirectory(const QString &directory);

    QQmlJSScope::Ptr localFile2QQmlJSScope(const QString &filePath);
    static void setQualifiedNamesOn(const Import &import);

    QStringList m_importPaths;

    QHash<std::pair<QString, QTypeRevision>, QString> m_seenImports;
    QHash<QQmlJS::Import, QSharedPointer<AvailableTypes>> m_cachedImportTypes;
    QHash<QString, Import> m_seenQmldirFilesAndDirectories;

    QHash<QString, QQmlJSScope::Ptr> m_importedFiles;
    QList<QQmlJS::DiagnosticMessage> m_globalWarnings;
    std::optional<AvailableTypes> m_builtins;

    QQmlJSResourceFileMapper *m_mapper = nullptr;
    QQmlJSResourceFileMapper *m_metaDataMapper = nullptr;
    QQmlJSImporterFlags m_flags;
    bool useOptionalImports() const { return m_flags.testFlag(UseOptionalImports); };
    bool preferQmlFilesFromSourceFolder() const
    {
        return m_flags.testFlag(PreferQmlFilesFromSourceFolder);
    };

    ImportVisitor m_importVisitor;
};

QT_END_NAMESPACE

#endif // QQMLJSIMPORTER_P_H
