/**

 * @file metadata.c

 * @author Radek Krejci <rkrejci@cesnet.cz>

 * @brief libyang extension plugin - Metadata (RFC 7952)

 *

 * Copyright (c) 2019 CESNET, z.s.p.o.

 *

 * This source code is licensed under BSD 3-Clause License (the "License").

 * You may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *     https://opensource.org/licenses/BSD-3-Clause

 */

#include "metadata.h"

#include <stdint.h>

#include <stdlib.h>

#include <string.h>

#include "libyang.h"

#include "plugins_exts.h"

/**

 * @brief Representation of the compiled metadata substatements - simplify storage for the items available via

 * ::lysc_ext_substmt.

 */

struct lyext_metadata {

    struct lysc_type *type;            /**< type of the metadata (mandatory) */

    const char *units;                 /**< units of the leaf's type */

    struct lysc_iffeature *iffeatures; /**< list of if-feature expressions ([sized array](@ref sizedarrays)) */

    const char *dsc;                   /**< description */

    const char *ref;                   /**< reference */

    uint16_t flags;                    /**< [schema node flags](@ref snodeflags) - only LYS_STATUS_* values are allowed */

};

/**

 * @brief Compile annotation extension instances.

 *

 * Implementation of ::lyplg_ext_compile_clb callback set as lyext_plugin::compile.

 */

static LY_ERR

annotation_compile(struct lysc_ctx *cctx, const struct lysp_ext_instance *p_ext, struct lysc_ext_instance *c_ext)

{

    LY_ERR ret;

    struct lyext_metadata *annotation;

    struct lysc_module *mod_c;

    LY_ARRAY_COUNT_TYPE u;

    /* annotations can appear only at the top level of a YANG module or submodule */

    if ((c_ext->parent_stmt != LY_STMT_MODULE) && (c_ext->parent_stmt != LY_STMT_SUBMODULE)) {

        lyplg_ext_log(c_ext, LY_LLERR, LY_EVALID, lysc_ctx_get_path(cctx),

                "Extension %s is allowed only at the top level of a YANG module or submodule, but it is placed in \"%s\" statement.",

                p_ext->name, ly_stmt2str(c_ext->parent_stmt));

        return LY_EVALID;

    }

    /* check mandatory argument */

    if (!c_ext->argument) {

        lyplg_ext_log(c_ext, LY_LLERR, LY_EVALID, lysc_ctx_get_path(cctx),

                "Extension %s is instantiated without mandatory argument representing metadata name.", p_ext->name);

        return LY_EVALID;

    }

    mod_c = (struct lysc_module *)c_ext->parent;

    /* check for duplication */

    LY_ARRAY_FOR(mod_c->exts, u) {

        if ((&mod_c->exts[u] != c_ext) && (mod_c->exts[u].def == c_ext->def) && !strcmp(mod_c->exts[u].argument, c_ext->argument)) {

            /* duplication of the same annotation extension in a single module */

            lyplg_ext_log(c_ext, LY_LLERR, LY_EVALID, lysc_ctx_get_path(cctx), "Extension %s is instantiated multiple times.", p_ext->name);

            return LY_EVALID;

        }

    }

    /* compile annotation substatements */

    c_ext->data = annotation = calloc(1, sizeof *annotation);

    if (!annotation) {

        goto emem;

    }

    LY_ARRAY_CREATE_GOTO(lysc_ctx_get_ctx(cctx), c_ext->substmts, 6, ret, emem);

    LY_ARRAY_INCREMENT(c_ext->substmts);

    c_ext->substmts[ANNOTATION_SUBSTMT_IFF].stmt = LY_STMT_IF_FEATURE;

    c_ext->substmts[ANNOTATION_SUBSTMT_IFF].cardinality = LY_STMT_CARD_ANY;

    c_ext->substmts[ANNOTATION_SUBSTMT_IFF].storage = &annotation->iffeatures;

    LY_ARRAY_INCREMENT(c_ext->substmts);

    c_ext->substmts[ANNOTATION_SUBSTMT_UNITS].stmt = LY_STMT_UNITS;

    c_ext->substmts[ANNOTATION_SUBSTMT_UNITS].cardinality = LY_STMT_CARD_OPT;

    c_ext->substmts[ANNOTATION_SUBSTMT_UNITS].storage = &annotation->units;

    LY_ARRAY_INCREMENT(c_ext->substmts);

    c_ext->substmts[ANNOTATION_SUBSTMT_STATUS].stmt = LY_STMT_STATUS;

    c_ext->substmts[ANNOTATION_SUBSTMT_STATUS].cardinality = LY_STMT_CARD_OPT;

    c_ext->substmts[ANNOTATION_SUBSTMT_STATUS].storage = &annotation->flags;

    LY_ARRAY_INCREMENT(c_ext->substmts);

    c_ext->substmts[ANNOTATION_SUBSTMT_TYPE].stmt = LY_STMT_TYPE;

    c_ext->substmts[ANNOTATION_SUBSTMT_TYPE].cardinality = LY_STMT_CARD_MAND;

    c_ext->substmts[ANNOTATION_SUBSTMT_TYPE].storage = &annotation->type;

    LY_ARRAY_INCREMENT(c_ext->substmts);

    c_ext->substmts[ANNOTATION_SUBSTMT_DSC].stmt = LY_STMT_DESCRIPTION;

    c_ext->substmts[ANNOTATION_SUBSTMT_DSC].cardinality = LY_STMT_CARD_OPT;

    c_ext->substmts[ANNOTATION_SUBSTMT_DSC].storage = &annotation->dsc;

    LY_ARRAY_INCREMENT(c_ext->substmts);

    c_ext->substmts[ANNOTATION_SUBSTMT_REF].stmt = LY_STMT_REFERENCE;

    c_ext->substmts[ANNOTATION_SUBSTMT_REF].cardinality = LY_STMT_CARD_OPT;

    c_ext->substmts[ANNOTATION_SUBSTMT_REF].storage = &annotation->ref;

    ret = lys_compile_extension_instance(cctx, p_ext, c_ext);

    return ret;

emem:

    lyplg_ext_log(c_ext, LY_LLERR, LY_EMEM, lysc_ctx_get_path(cctx), "Memory allocation failed (%s()).", __func__);

    return LY_EMEM;

}

/**

 * @brief INFO printer

 *

 * Implementation of ::lyplg_ext_schema_printer_clb set as ::lyext_plugin::sprinter

 */

static LY_ERR

annotation_schema_printer(struct lyspr_ctx *ctx, struct lysc_ext_instance *ext, ly_bool *flag)

{

    lysc_print_extension_instance(ctx, ext, flag);

    return LY_SUCCESS;

}

/**

 * @brief Free annotation extension instances' data.

 *

 * Implementation of ::lyplg_ext_free_clb callback set as ::lyext_plugin::free.

 */

static void

annotation_free(struct ly_ctx *ctx, struct lysc_ext_instance *ext)

{

    if (!ext->substmts) {

        return;

    }

    lyplg_ext_instance_substatements_free(ctx, ext->substmts);

    free(ext->data);

}

/**

 * @brief Plugin descriptions for the Metadata's annotation extension

 *

 * Note that external plugins are supposed to use:

 *

 *   LYPLG_EXTENSIONS = {

 */

const struct lyplg_ext_record plugins_metadata[] = {

    {

        .module = "ietf-yang-metadata",

        .revision = "2016-08-05",

        .name = "annotation",

        .plugin.id = "libyang 2 - metadata, version 1",

        .plugin.compile = &annotation_compile,

        .plugin.validate = NULL,

        .plugin.sprinter = &annotation_schema_printer,

        .plugin.free = annotation_free

    },

    {0}     /* terminating zeroed record */

};