/*
   sslh-ev: mono-processus server based on libev

# Copyright (C) 2021  Yves Rutschle
# 
# 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.
# 
# The full text for the General Public License is here:
# http://www.gnu.org/licenses/gpl.html

*/

#include <stdlib.h>
#include <ev.h>
#include "gap.h"
#include "log.h"
#include "udp-listener.h"
#include "tcp-listener.h"


const char* server_type = "sslh-ev";

static struct ev_loop* loop;

/* Libev watchers */
struct watchers {
    /* one set of ev_io for read, one for write, indexed by file descriptor */
    gap_array *ev_ior, *ev_iow;

    struct listen_endpoint* listen_sockets;
    gap_array* fd2ls;  /* Array indexed by file descriptor, pointing to listen_sockets */

    int max_fd; /* legacy to be removed, still required for UDP */
};

static void cnx_read_cb(EV_P_ ev_io *w, int revents);
static void cnx_write_cb(EV_P_ ev_io *w, int wevents);
static void cnx_accept_cb(EV_P_ ev_io *w, int revents);


static void watchers_init(watchers** w, struct listen_endpoint* listen_sockets, 
                          int num_addr_listen)
{
    *w = malloc(sizeof(**w));
    (*w)->ev_ior = gap_init(num_addr_listen);
    (*w)->ev_iow = gap_init(num_addr_listen);
    (*w)->listen_sockets = listen_sockets;
    (*w)->fd2ls = gap_init(0);

    /* Create watchers for listen sockets */
    for (int i = 0; i < num_addr_listen; i++) {
        ev_io* io = malloc(sizeof(*io));

        ev_io_init(io, &cnx_accept_cb, listen_sockets[i].socketfd, EV_READ);
        ev_io_start(EV_A_  io);
        gap_set((*w)->ev_ior, i, io);
        gap_set((*w)->fd2ls, listen_sockets[i].socketfd, &listen_sockets[i]);
        set_nonblock(listen_sockets[i].socketfd);
    }
}

void watchers_add_read(watchers* w, int fd)
{
    ev_io* io = gap_get(w->ev_ior, fd);
    if (!io) {
        io = malloc(sizeof(*io));
        ev_io_init(io, &cnx_read_cb, fd, EV_READ);
        ev_io_set(io, fd, EV_READ);

        gap_set(w->ev_ior, fd, io);
    }
    ev_io_start(loop, io);

    if (fd > w->max_fd) w->max_fd = fd + 1;
}

void watchers_del_read(watchers* w, int fd)
{
    ev_io* io = gap_get(w->ev_ior, fd);
    if (io) ev_io_stop(EV_A_ io);
}

void watchers_add_write(watchers* w, int fd)
{
    ev_io* io = gap_get(w->ev_iow, fd);
    if (!io) {
        io = malloc(sizeof(*io));
        ev_io_init(io, &cnx_write_cb, fd, EV_WRITE);
        ev_io_set(io, fd, EV_WRITE);

        gap_set(w->ev_iow, fd, io);
    }
    ev_io_start(loop, io);

    if (fd > w->max_fd) w->max_fd = fd + 1;
}

void watchers_del_write(watchers* w, int fd)
{
    ev_io* io = gap_get(w->ev_iow, fd);
    if (io) ev_io_stop(EV_A_ io);
}

/* /watchers */

#include "processes.h"

/* Libev callbacks */
static void cnx_read_cb(EV_P_ ev_io *w, int revents)
{
    struct loop_info* info = ev_userdata(EV_A);
    cnx_read_process(info, w->fd);
}

static void cnx_write_cb(EV_P_ ev_io *w, int wevents)
{
    struct loop_info* info = ev_userdata(EV_A);
    cnx_write_process(info, w->fd);
}


static void cnx_accept_cb(EV_P_ ev_io *w, int revents)
{
    struct loop_info* info = ev_userdata(EV_A);
    cnx_accept_process(info, gap_get(info->watchers->fd2ls, w->fd));
}

void main_loop(struct listen_endpoint listen_sockets[], int num_addr_listen)
{
    struct loop_info ev_info = {0};
    loop = EV_DEFAULT;

    ev_info.collection = collection_init(0);
    ev_info.probing_list = gap_init(0);
    udp_init(&ev_info);
    tcp_init();

    watchers_init(&ev_info.watchers, listen_sockets, num_addr_listen);
    ev_set_userdata(EV_A_ &ev_info);

    ev_run(EV_A_ 0);
}

void start_shoveler(int listen_socket) {
    print_message(msg_config_error, "inetd mode is not supported in libev mode\n");
    exit(1);
}