dynamicFileFormatContext.h

//
// Copyright 2019 Pixar
//
// Licensed under the terms set forth in the LICENSE.txt file available at
// https://openusd.org/license.
//
#ifndef PXR_USD_PCP_DYNAMIC_FILE_FORMAT_CONTEXT_H
#define PXR_USD_PCP_DYNAMIC_FILE_FORMAT_CONTEXT_H

#include "pxr/pxr.h"
#include "pxr/usd/pcp/api.h"
#include "pxr/usd/pcp/node.h"

PXR_NAMESPACE_OPEN_SCOPE

class PcpPrimIndex_StackFrame;
class PcpCache;

class PcpDynamicFileFormatContext
{
public:
    using VtValueVector = std::vector<VtValue>;

    PCP_API
    ~PcpDynamicFileFormatContext() = default;

    PCP_API
    bool ComposeValue(const TfToken &field, VtValue *value) const;

    PCP_API
    bool ComposeValueStack(const TfToken &field, 
                           VtValueVector *values) const;

    PCP_API
    bool ComposeAttributeDefaultValue(
        const TfToken &attributeName, VtValue *value) const;

private:
    PcpDynamicFileFormatContext(
        const PcpNodeRef &parentNode, 
        const SdfPath &pathInNode,
        int arcNum,
        PcpPrimIndex_StackFrame *previousFrame,
        TfToken::Set *composedFieldNames,
        TfToken::Set *composedAttributeNames);

    friend PcpDynamicFileFormatContext Pcp_CreateDynamicFileFormatContext(
        const PcpNodeRef &, const SdfPath&, int, PcpPrimIndex_StackFrame *, 
        TfToken::Set *, TfToken::Set *);

    bool _IsAllowedFieldForArguments(
        const TfToken &field, bool *fieldValueIsDictionary = nullptr) const;

private:
    PcpNodeRef _parentNode;
    SdfPath _pathInNode;
    int _arcNum;
    PcpPrimIndex_StackFrame *_previousStackFrame;

    // Cached names of fields that had values composed by this context.
    TfToken::Set *_composedFieldNames;

    // Cached names of attributes that had default values composed by this 
    // context.
    TfToken::Set *_composedAttributeNames;

    // Declare private helper.
    class _ComposeValueHelper;
};

PXR_NAMESPACE_CLOSE_SCOPE

#endif // PXR_USD_PCP_DYNAMIC_FILE_FORMAT_CONTEXT_H