/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *
 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "cx/tree.h"
#include "cx/linked_list.h"

#define CX_TR_PTR(cur, off) *((void**)(((char*)(cur))+(off)))

void cx_tree_add_sibling(void *node, ptrdiff_t loc_prev, ptrdiff_t loc_next, ptrdiff_t loc_parent, void *new_node) {
    cx_linked_list_add(&node, NULL, loc_prev, loc_next, new_node);

    // optional parent link
    if (loc_parent >= 0) {
        CX_TR_PTR(new_node, loc_parent) = CX_TR_PTR(node, loc_parent);
    }
}

void cx_tree_add_child(void **children_begin, void **children_end,
                  ptrdiff_t loc_prev, ptrdiff_t loc_next, void *new_node,
                  ptrdiff_t loc_parent, void *parent) {
    cx_linked_list_add(children_begin, children_end, loc_prev, loc_next, new_node);

    // optional parent link
    if (loc_parent >= 0) {
        CX_TR_PTR(new_node, loc_parent) = parent;
    }
}