schemaRegistry.h

//
// Copyright 2016 Pixar
//
// Licensed under the Apache License, Version 2.0 (the "Apache License")
// with the following modification; you may not use this file except in
// compliance with the Apache License and the following modification to it:
// Section 6. Trademarks. is deleted and replaced with:
//
// 6. Trademarks. This License does not grant permission to use the trade
//    names, trademarks, service marks, or product names of the Licensor
//    and its affiliates, except as required to comply with Section 4(c) of
//    the License and to reproduce the content of the NOTICE file.
//
// You may obtain a copy of the Apache License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the Apache License with the above modification is
// distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied. See the Apache License for the specific
// language governing permissions and limitations under the Apache License.
//
#ifndef PXR_USD_USD_SCHEMA_REGISTRY_H
#define PXR_USD_USD_SCHEMA_REGISTRY_H

#include "pxr/pxr.h"
#include "pxr/usd/usd/api.h"
#include "pxr/usd/usd/common.h"

#include "pxr/usd/sdf/layer.h"
#include "pxr/usd/sdf/primSpec.h"

#include "pxr/base/tf/hash.h"
#include "pxr/base/tf/singleton.h"

#include <unordered_map>
#include <vector>

PXR_NAMESPACE_OPEN_SCOPE

SDF_DECLARE_HANDLES(SdfAttributeSpec);
SDF_DECLARE_HANDLES(SdfRelationshipSpec);

class UsdSchemaBase;
class UsdPrimDefinition;

using UsdSchemaVersion = unsigned int;

class UsdSchemaRegistry : public TfWeakBase {
    UsdSchemaRegistry(const UsdSchemaRegistry&) = delete;
    UsdSchemaRegistry& operator=(const UsdSchemaRegistry&) = delete;
public:
    using TokenToTokenVectorMap = 
        std::unordered_map<TfToken, TfTokenVector, TfHash>;

    struct SchemaInfo {

        TfToken identifier;

        TfType type;

        TfToken family;

        UsdSchemaVersion version;

        UsdSchemaKind kind;
    };

    USD_API
    static UsdSchemaRegistry& GetInstance() {
        return TfSingleton<UsdSchemaRegistry>::GetInstance();
    }

    USD_API
    static TfToken
    MakeSchemaIdentifierForFamilyAndVersion(
        const TfToken &schemaFamily, 
        UsdSchemaVersion schemaVersion);

    USD_API
    static std::pair<TfToken, UsdSchemaVersion> 
    ParseSchemaFamilyAndVersionFromIdentifier(const TfToken &schemaIdentifier);

    USD_API
    static bool
    IsAllowedSchemaFamily(const TfToken &schemaFamily);

    USD_API
    static bool
    IsAllowedSchemaIdentifier(const TfToken &schemaIdentifier);

    USD_API
    static const SchemaInfo *
    FindSchemaInfo(const TfType &schemaType);

    template <class SchemaType>
    static const SchemaInfo *
    FindSchemaInfo() {
        static_assert(std::is_base_of<UsdSchemaBase, SchemaType>::value,
            "Provided type must derive UsdSchemaBase.");
        return FindSchemaInfo(SchemaType::_GetStaticTfType());
    }

    USD_API
    static const SchemaInfo *
    FindSchemaInfo(const TfToken &schemaIdentifier);

    USD_API
    static const SchemaInfo *
    FindSchemaInfo(const TfToken &schemaFamily, UsdSchemaVersion schemaVersion);

    enum class VersionPolicy {
        All,
        GreaterThan,
        GreaterThanOrEqual,
        LessThan,
        LessThanOrEqual
    };

    USD_API
    static const std::vector<const SchemaInfo *> &
    FindSchemaInfosInFamily(
        const TfToken &schemaFamily);

    USD_API
    static std::vector<const SchemaInfo *>
    FindSchemaInfosInFamily(
        const TfToken &schemaFamily, 
        UsdSchemaVersion schemaVersion, 
        VersionPolicy versionPolicy);

    USD_API
    static TfToken GetSchemaTypeName(const TfType &schemaType);

    template <class SchemaType>
    static
    TfToken GetSchemaTypeName() {
        return GetSchemaTypeName(SchemaType::_GetStaticTfType());
    }

    USD_API
    static TfToken GetConcreteSchemaTypeName(const TfType &schemaType);

    USD_API
    static TfToken GetAPISchemaTypeName(const TfType &schemaType);

    USD_API
    static TfType GetTypeFromSchemaTypeName(const TfToken &typeName);

    USD_API
    static TfType GetConcreteTypeFromSchemaTypeName(const TfToken &typeName);

    USD_API
    static TfType GetAPITypeFromSchemaTypeName(const TfToken &typeName);

    USD_API
    static bool IsDisallowedField(const TfToken &fieldName);

    USD_API
    static bool IsTyped(const TfType& primType);

    USD_API 
    static UsdSchemaKind GetSchemaKind(const TfType &schemaType);

    USD_API 
    static UsdSchemaKind GetSchemaKind(const TfToken &typeName);

    USD_API
    static bool IsConcrete(const TfType& primType);

    USD_API
    static bool IsConcrete(const TfToken& primType);

    USD_API
    static bool IsAbstract(const TfType& primType);

    USD_API
    static bool IsAbstract(const TfToken& primType);

    USD_API
    static bool IsAppliedAPISchema(const TfType& apiSchemaType);

    USD_API
    static bool IsAppliedAPISchema(const TfToken& apiSchemaType);

    USD_API
    static bool IsMultipleApplyAPISchema(const TfType& apiSchemaType);
    
    USD_API
    static bool IsMultipleApplyAPISchema(const TfToken& apiSchemaType);
        
    USD_API
    static TfType GetTypeFromName(const TfToken& typeName);

    USD_API
    static std::pair<TfToken, TfToken> GetTypeNameAndInstance(
            const TfToken &apiSchemaName);

    USD_API
    static bool IsAllowedAPISchemaInstanceName(
        const TfToken &apiSchemaName,
        const TfToken &instanceName);

    USD_API
    static const TfTokenVector &GetAPISchemaCanOnlyApplyToTypeNames(
        const TfToken &apiSchemaName, 
        const TfToken &instanceName = TfToken());

    USD_API
    static const TokenToTokenVectorMap &GetAutoApplyAPISchemas();

    USD_API
    static void CollectAddtionalAutoApplyAPISchemasFromPlugins(
        TokenToTokenVectorMap *autoApplyAPISchemas);

    USD_API
    static TfToken MakeMultipleApplyNameTemplate(
        const std::string &namespacePrefix, 
        const std::string &baseName);

    USD_API
    static TfToken MakeMultipleApplyNameInstance(
        const std::string &nameTemplate,
        const std::string &instanceName);

    USD_API
    static TfToken GetMultipleApplyNameTemplateBaseName(
        const std::string &nameTemplate);

    USD_API
    static bool IsMultipleApplyNameTemplate(
        const std::string &nameTemplate);

    const UsdPrimDefinition* FindConcretePrimDefinition(
        const TfToken &typeName) const {
        const auto it = _concreteTypedPrimDefinitions.find(typeName);
        return it != _concreteTypedPrimDefinitions.end() ? 
            it->second.get() : nullptr;
    }

    const UsdPrimDefinition *FindAppliedAPIPrimDefinition(
        const TfToken &typeName) const {
        const auto it = _appliedAPIPrimDefinitions.find(typeName);
        return it != _appliedAPIPrimDefinitions.end() ?
            it->second.primDef.get() : nullptr;
    }

    const UsdPrimDefinition *GetEmptyPrimDefinition() const {
        return _emptyPrimDefinition;
    }

    USD_API
    std::unique_ptr<UsdPrimDefinition>
    BuildComposedPrimDefinition(
        const TfToken &primType, const TfTokenVector &appliedAPISchemas) const;

    const VtDictionary &GetFallbackPrimTypes() const {
        return _fallbackPrimTypes;
    }

private:
    friend class TfSingleton<UsdSchemaRegistry>;

    UsdSchemaRegistry();

    using _FamilyAndInstanceToVersionMap = 
        std::unordered_map<std::pair<TfToken, TfToken>, UsdSchemaVersion, TfHash>;

    void _ComposeAPISchemasIntoPrimDefinition(
        UsdPrimDefinition *primDef, 
        const TfTokenVector &appliedAPISchemas,
        _FamilyAndInstanceToVersionMap *seenSchemaFamilyVersions,
        bool allowDupes = false) const;

    // Private class for helping initialize the schema registry. Defined 
    // entirely in the implementation. Declared here for private access to the
    // registry.
    class _SchemaDefInitHelper;

    std::vector<SdfLayerRefPtr> _schematicsLayers;

    std::unordered_map<TfToken, const std::unique_ptr<UsdPrimDefinition>,
         TfHash> _concreteTypedPrimDefinitions;

    struct _APISchemaDefinitionInfo {
        std::unique_ptr<UsdPrimDefinition> primDef;
        bool applyExpectsInstanceName;
    };
    std::unordered_map<TfToken, const _APISchemaDefinitionInfo, TfHash> 
        _appliedAPIPrimDefinitions;

    UsdPrimDefinition *_emptyPrimDefinition;

    VtDictionary _fallbackPrimTypes;

    friend class UsdPrimDefinition;
};

USD_API_TEMPLATE_CLASS(TfSingleton<UsdSchemaRegistry>);

// Utility function for extracting the metadata about applying API schemas from
// the plugin metadata for the schema's type. It is useful for certain clients
// to be able to access this plugin data in the same way that the 
// UsdSchemaRegistry does.
void Usd_GetAPISchemaPluginApplyToInfoForType(
    const TfType &apiSchemaType,
    const TfToken &apiSchemaName,
    UsdSchemaRegistry::TokenToTokenVectorMap *autoApplyAPISchemasMap,
    UsdSchemaRegistry::TokenToTokenVectorMap *canOnlyApplyAPISchemasMap,
    TfHashMap<TfToken, TfToken::Set, TfHash> *allowedInstanceNamesMap);

// Utility for sorting a list of auto-applied API schemas. It is useful for 
// certain clients to be able to make sure they can perform this type of sort
// in the exact same way as UsdSchemaRegistry does.
void Usd_SortAutoAppliedAPISchemas(
    TfTokenVector *autoAppliedAPISchemas);

PXR_NAMESPACE_CLOSE_SCOPE

#endif //PXR_USD_USD_SCHEMA_REGISTRY_H