/**

 * @file tree_data_free.c

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

 * @author Michal Vasko <mvasko@cesnet.cz>

 * @brief Freeing functions for data tree structures

 *

 * Copyright (c) 2019 - 2026 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 <assert.h>

#include <stdlib.h>

#include "dict.h"

#include "hash_table.h"

#include "log.h"

#include "ly_common.h"

#include "plugins_exts/metadata.h"

#include "plugins_internal.h"

#include "plugins_types.h"

#include "tree.h"

#include "tree_data.h"

#include "tree_data_internal.h"

#include "tree_data_sorted.h"

#include "tree_schema.h"

static void

lyd_free_meta(struct lyd_meta *meta, ly_bool siblings)

{

    struct lyd_meta *iter;

    if (!meta) {

        return;

    }

    if (meta->parent) {

        if (meta->parent->meta == meta) {

            if (siblings) {

                meta->parent->meta = NULL;

            } else {

                meta->parent->meta = meta->next;

            }

        } else {

            for (iter = meta->parent->meta; iter->next != meta; iter = iter->next) {}

            if (iter->next) {

                if (siblings) {

                    iter->next = NULL;

                } else {

                    iter->next = meta->next;

                }

            }

        }

    }

    if (!siblings) {

        meta->next = NULL;

    }

    for (iter = meta; iter; ) {

        meta = iter;

        iter = iter->next;

        lydict_remove(meta->annotation->module->ctx, meta->name);

        LYSC_GET_TYPE_PLG(meta->value.realtype->plugin_ref)->free(meta->annotation->module->ctx, &meta->value);

        free(meta);

    }

}

LIBYANG_API_DEF void

lyd_free_meta_single(struct lyd_meta *meta)

{

    lyd_free_meta(meta, 0);

}

LIBYANG_API_DEF void

lyd_free_meta_siblings(struct lyd_meta *meta)

{

    lyd_free_meta(meta, 1);

}

static void

lyd_free_attr(const struct ly_ctx *ctx, struct lyd_attr *attr, ly_bool siblings)

{

    struct lyd_attr *iter;

    LY_CHECK_ARG_RET(NULL, ctx, );

    if (!attr) {

        return;

    }

    if (attr->parent) {

        if (attr->parent->attr == attr) {

            if (siblings) {

                attr->parent->attr = NULL;

            } else {

                attr->parent->attr = attr->next;

            }

        } else {

            for (iter = attr->parent->attr; iter->next != attr; iter = iter->next) {}

            if (iter->next) {

                if (siblings) {

                    iter->next = NULL;

                } else {

                    iter->next = attr->next;

                }

            }

        }

    }

    if (!siblings) {

        attr->next = NULL;

    }

    for (iter = attr; iter; ) {

        attr = iter;

        iter = iter->next;

        ly_free_prefix_data(attr->format, attr->val_prefix_data);

        lydict_remove(ctx, attr->name.name);

        lydict_remove(ctx, attr->name.prefix);

        lydict_remove(ctx, attr->name.module_ns);

        lydict_remove(ctx, attr->value);

        free(attr);

    }

}

LIBYANG_API_DEF void

lyd_free_attr_single(const struct ly_ctx *ctx, struct lyd_attr *attr)

{

    lyd_free_attr(ctx, attr, 0);

}

LIBYANG_API_DEF void

lyd_free_attr_siblings(const struct ly_ctx *ctx, struct lyd_attr *attr)

{

    lyd_free_attr(ctx, attr, 1);

}

void

lyd_free_leafref_links_rec(struct lyd_leafref_links_rec *rec)

{

    LY_ARRAY_COUNT_TYPE u;

    struct lyd_leafref_links_rec *rec2;

    assert(rec);

    /* remove links of leafref nodes */

    LY_ARRAY_FOR(rec->leafref_nodes, u) {

        if (lyd_get_or_create_leafref_links_record(rec->leafref_nodes[u], &rec2, 0) == LY_SUCCESS) {

            LY_ARRAY_REMOVE_VALUE(rec2->target_nodes, rec->node);

            if ((LY_ARRAY_COUNT(rec2->leafref_nodes) == 0) && (LY_ARRAY_COUNT(rec2->target_nodes) == 0)) {

                lyd_free_leafref_nodes(rec->leafref_nodes[u]);

            }

        }

    }

    LY_ARRAY_FREE(rec->leafref_nodes);

    rec->leafref_nodes = NULL;

    /* remove links of target nodes */

    LY_ARRAY_FOR(rec->target_nodes, u) {

        if (lyd_get_or_create_leafref_links_record(rec->target_nodes[u], &rec2, 0) == LY_SUCCESS) {

            LY_ARRAY_REMOVE_VALUE(rec2->leafref_nodes, rec->node);

            if ((LY_ARRAY_COUNT(rec2->leafref_nodes) == 0) && (LY_ARRAY_COUNT(rec2->target_nodes) == 0)) {

                lyd_free_leafref_nodes(rec->target_nodes[u]);

            }

        }

    }

    LY_ARRAY_FREE(rec->target_nodes);

    rec->target_nodes = NULL;

}

void

lyd_free_leafref_nodes(const struct lyd_node_term *node)

{

    struct ly_ctx_shared_data *ctx_data;

    uint32_t hash;

    struct lyd_leafref_links_rec *rec;

    assert(node);

    if (lyd_get_or_create_leafref_links_record(node, &rec, 0)) {

        return;

    }

    /* free entry content */

    lyd_free_leafref_links_rec(rec);

    /* free entry itself from hash table */

    ctx_data = ly_ctx_shared_data_get(LYD_CTX(node));

    hash = lyht_hash((const char *)&node, sizeof node);

    /* LL LOCK */

    pthread_mutex_lock(&ctx_data->leafref_links_lock);

    lyht_remove(ctx_data->leafref_links_ht, &rec, hash);

    /* LL UNLOCK */

    pthread_mutex_unlock(&ctx_data->leafref_links_lock);

    free(rec);

}

/**

 * @brief Free Data (sub)tree.

 *

 * @param[in] node Data node to be freed.

 */

static void

lyd_free_subtree(struct lyd_node *node)

{

    struct lyd_node *iter, *next;

    struct lyd_node_opaq *opaq = NULL;

    assert(node);

    if (!node->schema) {

        opaq = (struct lyd_node_opaq *)node;

        /* free the children */

        LY_LIST_FOR_SAFE(lyd_child(node), next, iter) {

            lyd_free_subtree(iter);

        }

        lydict_remove(LYD_CTX(opaq), opaq->name.name);

        lydict_remove(LYD_CTX(opaq), opaq->name.prefix);

        lydict_remove(LYD_CTX(opaq), opaq->name.module_ns);

        lydict_remove(LYD_CTX(opaq), opaq->value);

        ly_free_prefix_data(opaq->format, opaq->val_prefix_data);

    } else if (node->schema->nodetype & LYD_NODE_INNER) {

        /* remove children hash table in case of inner data node */

        lyht_free(((struct lyd_node_inner *)node)->children_ht, NULL);

        /* free the children */

        LY_LIST_FOR_SAFE(lyd_child(node), next, iter) {

            lyd_free_subtree(iter);

        }

    } else if (node->schema->nodetype & LYD_NODE_ANY) {

        assert(!((struct lyd_node_any *)node)->children_ht);

        /* only frees the value this way */

        lyd_any_copy_value(node, NULL, 0, 0);

    } else if (node->schema->nodetype & LYD_NODE_TERM) {

        struct lyd_node_term *node_term = (struct lyd_node_term *)node;

        LYSC_GET_TYPE_PLG(((struct lysc_node_leaf *)node->schema)->type->plugin_ref)->free(LYD_CTX(node), &node_term->value);

        lyd_free_leafref_nodes(node_term);

    }

    if (!node->schema) {

        lyd_free_attr_siblings(LYD_CTX(node), opaq->attr);

    } else {

        /* free the node's metadata */

        lyd_free_meta_siblings(node->meta);

    }

    free(node);

}

LIBYANG_API_DEF void

lyd_free_tree(struct lyd_node *node)

{

    if (!node) {

        return;

    }

    if (lysc_is_key(node->schema) && node->parent) {

        LOGERR(LYD_CTX(node), LY_EINVAL, "Cannot free a list key \"%s\", free the list instance instead.", LYD_NAME(node));

        return;

    }

    lyd_unlink(node);

    lyd_free_subtree(node);

}

static void

lyd_free_(struct lyd_node *node)

{

    struct lyd_node *iter, *next, *first_sibling = NULL;

    if (!node) {

        return;

    }

    LY_LIST_FOR_SAFE(lyd_first_sibling(node), next, iter) {

        if (lysc_is_key(iter->schema) && iter->parent) {

            LOGERR(LYD_CTX(iter), LY_EINVAL, "Cannot free a list key \"%s\", free the list instance instead.", LYD_NAME(iter));

            return;

        }

        /* in case of the top-level nodes (node->parent is NULL), no unlinking needed */

        if (iter->parent) {

            lyds_free_metadata(iter);

            lyd_unlink_ignore_lyds(&first_sibling, iter);

        }

        lyd_free_subtree(iter);

    }

}

LIBYANG_API_DEF void

lyd_free_siblings(struct lyd_node *node)

{

    lyd_free_(node);

}

LIBYANG_API_DEF void

lyd_free_all(struct lyd_node *node)

{

    if (!node) {

        return;

    }

    /* get top-level node */

    for ( ; node->parent; node = node->parent) {}

    lyd_free_(node);

}