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

#include "include.h"

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

static void dict_rehash(dict_t* s, size_t capacity) {
    dnode_t **nodes, *c, *n, **p;
    size_t  i;

    i     = s->capacity;
    nodes = calloc(sizeof(*nodes), capacity);

    while (i--) {
        c = s->nodes[i];

        while (!is_null(c)) {
            p  = nodes + (vnode_hash(&c->key, c->key_type) % capacity);
            n  = c->prev;
            c->prev = *p;

           *p = c;
            c = n;
        }
    }

    free(s->nodes);
    s->nodes    = nodes;
    s->capacity = capacity;
}

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

bool libcdsb_dict_shrink_to_fit(dict_t* s) {

    size_t capacity;

    capacity  = (s->size / CAPACITY_BLOCK) + 1;
    capacity *= CAPACITY_BLOCK;

    while (((double)s->size / capacity) > 0.65)
        capacity += CAPACITY_BLOCK;

    if (capacity >= s->capacity)
        return false;

    dict_rehash(s, capacity);

    return true;
}


bool libcdsb_dict_update(dict_t* x, const void* k, vtype kt, const void* v, vtype vt) {
    dnode_t *c, **p;

    if (!x->capacity || (double)x->size / x->capacity > REBUILD_POINT_MAX)
        dict_rehash(x, x->capacity + CAPACITY_BLOCK);

    c = *(p = x->nodes + (vtype_hash(k, kt) % x->capacity));

    while (!is_null(c)) {
        if (vtype_compare(k, kt, vnode_peek(&c->key, c->key_type), c->key_type) == 0) {
            vnode_free(&c->value, c->value_type);

            c->value      = vnode_create(v, vt);
            c->value_type = vt;

            return true;
        } else c = c->prev;
    }

    c = malloc(sizeof(*c));

    c->prev       = *p;
    c->key        = vnode_create(k, kt);
    c->value      = vnode_create(v, vt);
    c->key_type   = kt;
    c->value_type = vt;

    *p = c;
    ++x->size;

    return false;
}


int libcdsb_dict_find(dict_t* x, const void* k, vtype t, void* dt, dict_access_callback callback, bool cut) {
    dnode_t *c, **p;
    int           r;
    void*       key;

    if (x->capacity) {
        c = *(p = x->nodes + (vtype_hash(k, t) % x->capacity));

        while (!is_null(c)) {
            key = vnode_peek(&c->key, c->key_type);
            if (vtype_compare(k, t, key, c->key_type) == 0) {
                r = (callback) ? callback(key, c->key_type, vnode_peek(&c->value, c->value_type), c->value_type, dt) : 0;

                if (cut) {
                    *p = c->prev;
                    vnode_free(&c->key,   c->key_type);
                    vnode_free(&c->value, c->value_type);
                    free(c);
                    --x->size;
                }

                return r;
            } else c = *(p = &c->prev);
        }
    }

    return -1;
}


int libcdsb_dict_foreach(dict_t* x, void* dt, dict_access_callback callback, bool flush) {
    dnode_t *c;
    ssize_t  i;
    int      r;

    r = 0;
    i = x->capacity;

    while (i) {
        c = x->nodes[--i];

        while (!is_null(c)) {
            r = callback(vnode_peek(&c->key,   c->key_type),   c->key_type,
                         vnode_peek(&c->value, c->value_type), c->value_type, dt);

            c = c->prev;

            if (r) {
                if (!flush) goto end_;
                else goto flush_loop_;
            } else if (flush) {
                vnode_free(&x->nodes[i]->key,   x->nodes[i]->key_type);
                vnode_free(&x->nodes[i]->value, x->nodes[i]->value_type);
                free(x->nodes[i]);

                x->nodes[i] = c;
            }
        }
    }

    if (flush) {
        while (i) {
            --i;

            while (!is_null(x->nodes[i])) { flush_loop_:
                vnode_free(&x->nodes[i]->key,   x->nodes[i]->key_type);
                vnode_free(&x->nodes[i]->value, x->nodes[i]->value_type);

                c = x->nodes[i]->prev;
                free(x->nodes[i]);

                x->nodes[i] = c;
            }
        }

        free(x->nodes);
        memset(x, 0, sizeof(*x));
    }

  end_:
    return r;
}