/*
 * Copyright (c) 2012-2020 The Khronos Group Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef _VX_KHR_XML_H_
#define _VX_KHR_XML_H_

/*! \file
 * \brief The OpenVX XML Schema Extension Header.
 *
 * \defgroup group_xml Extension: XML API
 * \brief The Khronos Extension for OpenVX XML Import and Export Support.
 */

#define OPENVX_KHR_XML  "vx_khr_xml"

#include <VX/vx.h>

/*! \brief The Object Type Enumeration for Imports.
 * \ingroup group_xml
 */
enum vx_ext_import_type_e {
    VX_TYPE_IMPORT = 0x814,/*!< \brief A <tt>\ref vx_import</tt> */
};

/*! \brief The import type enumeration.
 * \ingroup group_xml
 * \see VX_IMPORT_ATTRIBUTE_TYPE
 */
enum vx_ext_import_types_e {
    VX_IMPORT_TYPE_XML = 0,/*!< \brief The XML import type */
};

/*! \brief The import attributes list
 * \ingroup group_xml
 * \see vxQueryImport
 */
enum vx_import_attribute_e {
    /*! \brief Returns the number of references in the import object. Use a <tt>\ref vx_uint32</tt> parameter.*/
    VX_IMPORT_ATTRIBUTE_COUNT = VX_ATTRIBUTE_BASE(VX_ID_KHRONOS, VX_TYPE_IMPORT) + 0x0,
    /*! \brief Returns the type of import. Use a <tt>\ref vx_ext_import_types_e </tt> parameter */
    VX_IMPORT_ATTRIBUTE_TYPE = VX_ATTRIBUTE_BASE(VX_ID_KHRONOS, VX_TYPE_IMPORT) + 0x1,
};

/*! \brief An abstract handle to an import object.
 * \ingroup group_xml
 * \extends vx_reference
 */
typedef struct _vx_import *vx_import;


#ifdef __cplusplus
extern "C" {
#endif

/*! \brief Exports all objects in the context to an XML file which uses the OpenVX
 * XML Schema.
 * \param [in] context The context to export.
 * \param [in] xmlfile The file name to write the XML into.
 * \note The reference numbers contained in the xml file can appear in any order but
 * should be inclusive from index number 0 to [number of references - 1]. For example,
 * if there are 20 references in the xml file, none of the reference indices should be >= 20.
 * \return A <tt>\ref vx_status_e</tt> enumeration.
 * \see https://www.khronos.org/registry/vx/schema/openvx-1-1.xsd
 * \ingroup group_xml
 */
VX_API_ENTRY vx_status VX_API_CALL vxExportToXML(vx_context context, vx_char xmlfile[]);


/*! \brief Imports all framework and data objects from an XML file into the given context.
 * \param [in] context The context to import into.
 * \param [in] xmlfile The XML file to read.
 * \note The reference indices in the import object corresponds with the reference numbers in the
 * XML file. It is assumed that the program has some means to know which references to use from
 * imported list (either by name: <tt>\ref vxGetImportReferenceByName</tt>, or by index from looking at the XML
 * file (debug use case): <tt>\ref vxGetImportReferenceByIndex</tt>).  Alternativly, the program can use
 * <tt>\ref vxGetImportReferenceByIndex</tt> in a loop and query each one to understand what was imported. After
 * all references of interest have been retrieved, this import obects should be released using
 * <tt>\ref vxReleaseImport</tt>.
 * \return \ref vx_import object containing references to the imported objects in the context
 * \see https://www.khronos.org/registry/vx/schema/openvx-1-1.xsd
 * \ingroup group_xml
 */
VX_API_ENTRY vx_import VX_API_CALL vxImportFromXML(vx_context context, vx_char xmlfile[]);

/*! \brief Used to retrieve a reference by name from the import when the name is known beforehand.  If
 *  multiple references have the same name, then *any* one of them may be returned.
 * \param [in] import The reference to the import object.
 * \param [in] name The reference string name.
 * \return <tt>\ref vx_reference</tt>
 * \retval 0 Invalid import object or name does not match a reference in the import object.
 * \retval * The reference matching the requested name.
 * \note Use <tt>\ref vxReleaseReference</tt> to release the reference before releasing the context.
 * \pre <tt>\ref vxImportFromXML</tt>
 * \ingroup group_xml
 */
VX_API_ENTRY vx_reference VX_API_CALL vxGetImportReferenceByName(vx_import import, const vx_char *name);

/*! \brief Used to retrieve a reference by the index from the import.
 * \param [in] import The reference to the import object.
 * \param [in] index The index of the reference in the import object to return.
 * \return <tt>\ref vx_reference</tt>
 * \retval 0 Invalid import object or index.
 * \retval * The reference at the requested index number.
 * \note Use <tt>\ref vxQueryImport</tt> with <tt>\ref VX_IMPORT_ATTRIBUTE_COUNT</tt> to retrieve
 * the upper limit of references in the import.
 * \note Use <tt>\ref vxReleaseReference</tt> to release the reference before releasing the context.
 * \pre <tt>\ref vxImportFromXML</tt>
 * \ingroup group_xml
 */
VX_API_ENTRY vx_reference VX_API_CALL vxGetImportReferenceByIndex(vx_import import, vx_uint32 index);

/*! \brief Used to query the import about its properties.
 * \param [in] import The reference to the import object.
 * \param [in] attribute The <tt>\ref vx_import_attribute_e</tt> value to query for.
 * \param [out] ptr The location at which the resulting value will be stored.
 * \param [in] size The size of the container to which ptr points.
 * \return A <tt>\ref vx_status_e</tt> enumeration.
 * \pre <tt>\ref vxImportFromXML</tt>
 * \ingroup group_xml
 */
VX_API_ENTRY vx_status VX_API_CALL vxQueryImport(vx_import import, vx_enum attribute, void *ptr, vx_size size);

/*! \brief Releases a reference to an import object.
 * Also internally releases its references to its imported objects. These
 * imported objects may not be garbage collected until their total reference
 * counts are zero.
 * \param [in] import The pointer to the import object to release.
 * \return A <tt>\ref vx_status_e</tt> enumeration.
 * \retval VX_SUCCESS No errors.
 * \retval VX_ERROR_INVALID_REFERENCE If import is not a <tt>\ref vx_import</tt>.
 * \note After returning from this function the reference will be zeroed.
 * \pre <tt>\ref vxImportFromXML</tt>
 * \ingroup group_xml
 */
VX_API_ENTRY vx_status VX_API_CALL vxReleaseImport(vx_import *import);

#ifdef __cplusplus
}
#endif

#endif