/**
 * @file tree_schema_internal.h
 * @author Radek Krejci <rkrejci@cesnet.cz>
 * @brief internal functions for YANG schema trees.
 *
 * Copyright (c) 2015 - 2018 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
 */

#ifndef LY_TREE_SCHEMA_INTERNAL_H_
#define LY_TREE_SCHEMA_INTERNAL_H_

/**
 * @brief List of YANG statement groups - the (sub)module's substatements
 */
enum yang_module_stmt {
    Y_MOD_MODULE_HEADER,
    Y_MOD_LINKAGE,
    Y_MOD_META,
    Y_MOD_REVISION,
    Y_MOD_BODY
};

/**
 * @brief Types of arguments of YANG statements
 */
enum yang_arg {
    Y_IDENTIF_ARG,        /**< YANG "identifier-arg-str" rule */
    Y_PREF_IDENTIF_ARG,   /**< YANG "identifier-ref-arg-str" rule */
    Y_STR_ARG,            /**< YANG "string" rule */
    Y_MAYBE_STR_ARG       /**< optional YANG "string" rule */
};

/**
 * @brief internal context for schema parsers
 */
struct ly_parser_ctx {
    struct ly_ctx *ctx;
    uint64_t line;      /* line number */
    uint64_t indent;    /* current position on the line for YANG indentation */
};

/**
 * @brief Check the currently present prefixes in the module for collision with the new one.
 *
 * @param[in] ctx yang parser context.
 * @param[in] module Schema tree to check.
 * @param[in] value Newly added prefix value (including its location to distinguish collision with itself).
 * @return LY_EEXIST when prefix is already used in the module, LY_SUCCESS otherwise
 */
LY_ERR lysp_check_prefix(struct ly_parser_ctx *ctx, struct lysp_module *module, const char **value);

/**
 * @brief Check date string (4DIGIT "-" 2DIGIT "-" 2DIGIT)
 *
 * @param[in] ctx Context to store log message.
 * @param[in] date Date string to check (non-necessarily terminated by \0)
 * @param[in] date_len Length of the date string, 10 expected.
 * @param[in] stmt Statement name for error message.
 * @return LY_ERR value.
 */
LY_ERR lysp_check_date(struct ly_ctx *ctx, const char *date, int date_len, const char *stmt);

/**
 * @brief Just move the newest revision into the first position, does not sort the rest
 * @param[in] revs Sized-array of the revisions in a printable schema tree.
 */
void lysp_sort_revisions(struct lysp_revision *revs);

/**
 * @brief Find the module referenced by prefix in the provided mod.
 *
 * @param[in] mod Schema module where the prefix was used.
 * @param[in] prefix Prefix used to reference a module.
 * @param[in] len Length of the prefix since it is not necessary NULL-terminated.
 * @return Pointer to the module or NULL if the module is not found.
 */
struct lysc_module *lysc_module_find_prefix(struct lysc_module *mod, const char *prefix, size_t len);

/**
 * @brief Free the schema structure. It just frees, it does not remove the schema from its context.
 * @param[in,out] module Schema module structure to free.
 * @param[in] private_destructor Function to remove private data from the compiled schema tree.
 */
void lys_module_free(struct lys_module *module, void (*private_destructor)(const struct lysc_node *node, void *priv));

/**
 * @brief
 */
LY_ERR yang_parse(struct ly_ctx *ctx, const char *data, struct lysp_module **mod_p);

#endif /* LY_TREE_SCHEMA_INTERNAL_H_ */