#include "server.h"

#include <stdio.h>
#include <string.h>

#include <errno.h>
#include <netdb.h>
#include <netinet/in.h>
#include <sys/epoll.h>
#include <sys/socket.h>
#include <unistd.h>

/*
 * Macros
 */
#define LISTEN_BACKLOG      (2048)

/*
 * Data
 */
static int _fd = -1;

/*
 * Private API
 */
bool _accept() {
    close(accept(_fd, 0, 0));
    return true;
}

/*
 * Public API
 */
int server_open(const char* host, int port) {
    struct hostent *he = gethostbyname(host);
    if (!he) {
        fprintf(stderr, "[!] gethostbyname failed: %d (h_errno)\n", h_errno);
        return -1;
    }
    _fd = socket(
        AF_INET,
        SOCK_STREAM | SOCK_NONBLOCK,
        IPPROTO_TCP
    );
    if (_fd == -1) {
        fprintf(stderr, "[!] socket failed: %d\n", errno);
        return -1;
    }
    const int opt = 1;
    if (setsockopt(_fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt)) < 0) {
        close(_fd);
        fprintf(stderr, "[!] setsockopt failed: %d\n", errno);
        return -1;
    }
    struct sockaddr_in addr;
    addr.sin_family = AF_INET;
    addr.sin_port = htobe16(port);
    memcpy(&addr.sin_addr, he->h_addr, he->h_length);
    if (bind(_fd, (const void *)&addr, sizeof(addr)) == -1) {
        close(_fd);
        fprintf(stderr, "[!] bind failed: %d\n", errno);
        return -1;
    }
    if (listen(_fd, LISTEN_BACKLOG) == -1) {
        close(_fd);
        fprintf(stderr, "[!] listen failed: %d\n", errno);
        return -1;
    }
    return _fd;
}

void server_close() {
    shutdown(_fd, SHUT_RDWR);
    close(_fd);
}

bool server_event(uint32_t events) {
    if (events & EPOLLIN) {
        return _accept();
    }
    // we assume any event other than EPOLLIN is error
    return false;
}