/* This software is licensed by the MIT License, see LICENSE file */
/*                                Copyright © 2022 Gregory Lirent */

#include "../../include/set.h"
#include "../__internal/rbtree.h"

static inline hash_t rbnode_hash(const rbnode_t* s, vtype t) {
    return vnode_hash(&s->value, t);
}

/*#####################################################################################################################*/

size_t vset_size(const set_t* x) {
    stack_t   z;
    size_t    n;
    rbnode_t* c;

    stack_init(&z);
    stack_push(&z, x->root);

    n = 0;

    if (!rbnode_is_empty(x->root)) {
        while ((c = stack_pop(&z))) {
            ++n;
            if (!rbnode_is_empty(c->right)) stack_push(&z, c->right);
            if (!rbnode_is_empty(c->left))  stack_push(&z, c->left);
        }
    }

    return n;
}


hash_t vset_hash(const set_t* s) {

    stack_t         z;
    rbnode_t *c0, *c1;
    hash_t    hash, v;

    if (rbnode_is_empty(s->root))
        return 0;

    stack_init(&z);
    stack_push(&z, s->root->left);

    hash = 1;

    if (!rbnode_is_empty(c0 = stack_pop(&z))) {
        do {
            ++hash;
            if (!rbnode_is_empty(c0->right)) stack_push(&z,      c0->right);
            if (!rbnode_is_empty(c0->left))  stack_push(&z, c1 = c0->left);
        } while (!is_null(c0 = stack_pop(&z)));
    }

    v  = rbnode_hash(c1, s->type);
    stack_push(&z, s->root->right);

    if (!rbnode_is_empty(c0 = stack_pop(&z))) {
        do {
            ++hash;
            if (!rbnode_is_empty(c0->right)) stack_push(&z, c1 = c0->right);
            if (!rbnode_is_empty(c0->left))  stack_push(&z,      c0->left);
        } while (!is_null(c0 = stack_pop(&z)));
    }

    v += rbnode_hash(c1, s->type);

    return (hash ^ v) + VTYPE_SET;
}