/*
 * Ouroboros - Copyright (C) 2016
 *
 * The IPC Resource Manager - Application Instance Table
 *
 *    Dimitri Staessens <dimitri.staessens@intec.ugent.be>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <ouroboros/config.h>
#include <ouroboros/list.h>
#include <ouroboros/errno.h>
#include <ouroboros/time_utils.h>

#include "api_table.h"
#include "registry.h"

#include <stdlib.h>
#include <unistd.h>
#include <limits.h>

struct api_entry * api_entry_create(pid_t api, char * apn)
{
        struct api_entry * e;

        if (apn == NULL)
                return NULL;

        e = malloc(sizeof(*e));
        if (e == NULL)
                return NULL;

        INIT_LIST_HEAD(&e->next);
        INIT_LIST_HEAD(&e->names);

        e->api      = api;
        e->apn      = apn;
        e->daf_name = NULL;

        e->re       = NULL;

        e->state    = API_INIT;

        pthread_mutex_init(&e->state_lock, NULL);
        pthread_cond_init(&e->state_cond, NULL);

        return e;
}

void api_entry_destroy(struct api_entry * e)
{
        struct list_head * p;
        struct list_head * h;

        if (e == NULL)
                return;

        pthread_mutex_lock(&e->state_lock);

        if (e->state == API_DESTROY) {
                pthread_mutex_unlock(&e->state_lock);
                return;
        }

        if (e->state == API_SLEEP)
                e->state = API_DESTROY;

        pthread_cond_signal(&e->state_cond);

        while (e->state != API_INIT)
                pthread_cond_wait(&e->state_cond, &e->state_lock);

        pthread_mutex_unlock(&e->state_lock);

        pthread_cond_destroy(&e->state_cond);
        pthread_mutex_destroy(&e->state_lock);

        if (e->apn != NULL)
                free(e->apn);

        list_for_each_safe(p, h, &e->names) {
                struct str_el * n = list_entry(p, struct str_el, next);
                list_del(&n->next);
                if (n->str != NULL)
                        free(n->str);
                free(n);
        }

        free(e);
}

int api_entry_add_name(struct api_entry * e, char * name)
{
        struct str_el * s;
        if (e == NULL || name == NULL)
                return -EINVAL;

        s = malloc(sizeof(*s));
        if (s == NULL)
                return -ENOMEM;

        s->str = name;
        list_add(&s->next, &e->names);

        return 0;
}

void api_entry_del_name(struct api_entry * e, char * name)
{
        struct list_head * p = NULL;
        struct list_head * h = NULL;

        list_for_each_safe(p, h, &e->names) {
                struct str_el * s = list_entry(p, struct str_el, next);
                if (!wildcard_match(name, s->str)) {
                        list_del(&s->next);
                        if (s->str != NULL)
                                free(s->str);
                        free(s);
                }
        }
}

int api_entry_sleep(struct api_entry * e)
{
        struct timespec timeout = {(IRMD_ACCEPT_TIMEOUT / 1000),
                                   (IRMD_ACCEPT_TIMEOUT % 1000) * MILLION};
        struct timespec now;
        struct timespec dl;

        int ret = 0;

        if (e == NULL)
                return -EINVAL;

        e->re = NULL;

        clock_gettime(CLOCK_REALTIME, &now);

        ts_add(&now, &timeout, &dl);

        pthread_mutex_lock(&e->state_lock);
        if (e->state != API_INIT) {
                pthread_mutex_unlock(&e->state_lock);
                return -EINVAL;
        }

        e->state = API_SLEEP;

        while (e->state == API_SLEEP) {
                if ((ret = -pthread_cond_timedwait(&e->state_cond,
                                                   &e->state_lock,
                                                   &dl)) == -ETIMEDOUT) {
                        break;
                }
        }

        if (e->state == API_DESTROY)
                ret = -1;

        e->state = API_INIT;
        pthread_cond_broadcast(&e->state_cond);
        pthread_mutex_unlock(&e->state_lock);

        return ret;
}

void api_entry_wake(struct api_entry * e, struct reg_entry * re)
{
        if (e == NULL)
                return;

        pthread_mutex_lock(&e->state_lock);

        if (e->state != API_SLEEP) {
                pthread_mutex_unlock(&e->state_lock);
                return;
        }

        e->state = API_WAKE;
        e->re    = re;

        pthread_cond_broadcast(&e->state_cond);

        while (e->state == API_WAKE)
                pthread_cond_wait(&e->state_cond, &e->state_lock);

        pthread_mutex_unlock(&e->state_lock);
}

int api_table_add(struct list_head * api_table, struct api_entry * e)
{
        if (api_table == NULL || e == NULL)
                return -EINVAL;

        list_add(&e->next, api_table);

        return 0;
}

void api_table_del(struct list_head * api_table, pid_t api)
{
        struct list_head * p;
        struct list_head * h;

        list_for_each_safe(p, h, api_table) {
                struct api_entry * e = list_entry(p, struct api_entry, next);
                if (api == e->api) {
                        list_del(&e->next);
                        api_entry_destroy(e);
                }
        }
}

struct api_entry * api_table_get(struct list_head * api_table, pid_t api)
{
        struct list_head * h;

        list_for_each(h, api_table) {
                struct api_entry * e = list_entry(h, struct api_entry, next);
                if (api == e->api)
                        return e;
        }

        return NULL;
}