/*********************************************************************************
 *      Copyright:  (C) 2018 LingYun IoT Studio
 *                  All rights reserved.
 *
 *       Filename:  ddns_client.c
 *    Description:  This is a ddns client code to report public IP address to 
 *                  server, it just need to send the domain name, and server 
 *                  can get its public IP address.
 *                 
 *        Version:  1.0.0(1/1/2019)
 *         Author:  Guo Wenxue <guowenxue@gmail.com>
 *      ChangeLog:  1, Release initial version on "2019-1-1 01:38:08 PM"
 *                 
 ********************************************************************************/
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <getopt.h>
#include <libgen.h>

#include "iniparser.h"

#define MAX_HOSTS             3
#define PROG_VERSION          "v1.0.0"

int socket_send_domain(char *serverip, int port, char *msg);

static void program_usage(char *progname)
{ 
	printf("Usage: %s [OPTION]...\n", progname); 
	printf(" %s is LingYun studio DDNS client program to report public IP address\n", progname); 

	printf("\nMandatory arguments to long options are mandatory for short options too:\n"); 
	printf(" -c[conf    ]  Specify configure file\n"); 
	printf(" -h[help    ]  Display this help information\n"); 
	printf(" -v[version ]  Display the program version\n"); 
	
	printf("\n%s version %s\n", progname, PROG_VERSION); return;
}

int main(int argc, char **argv)
{
    char              *conf_file = "./ddns.conf";
    char              *progname=NULL;
    int                opt;
    dictionary        *ini;
    char              *str;
    int                val;
    char              *domain;
    char              *serverip;
    int                port;
    int                i;
    char               key[64];

    struct option long_options[] = { 
        {"conf", required_argument, NULL, 'c'},
        {"version", no_argument, NULL, 'v'},
        {"help", no_argument, NULL, 'h'},
        {NULL, 0, NULL, 0}
    }; 

    progname = (char *)basename(argv[0]);

    /*  Parser the command line parameters */ 
    while ((opt = getopt_long(argc, argv, "c:dvh", long_options, NULL)) != -1) 
    {   
        switch (opt)
        {   
            case 'c': /*  Set configure file */ 
                conf_file = optarg;
                break; 

            case 'v':  /*  Get software version */ 
                printf("%s version %s\n", progname, PROG_VERSION); 
                return 0; 

            case 'h':  /*  Get help information */ 
                program_usage(progname); 
                return 0; 

            default:
                break;
        } 
    } 

    ini = iniparser_load(conf_file); 
    if( !ini ) 
    {   
        printf("ERROR: cannot parse file: '%s'\n", conf_file); 
        return -1; 
    }   

    domain=iniparser_getstring(ini, "common:domain", NULL);
    if( !domain )
    {
        printf("ERROR: cannot parse domain in '%s'\n", conf_file); 
        return -1; 
    }

    for(i=1; i<MAX_HOSTS; i++)
    {
        memset(key, 0, sizeof(key));
        snprintf(key, sizeof(key), "host%d:ip", i);

        serverip = iniparser_getstring(ini, key, NULL);

        snprintf(key, sizeof(key), "host%d:port", i);
        port = iniparser_getint(ini, key, 0);

        if( !serverip || !port )
        {
            continue;
        }

        printf("==> Start send domain '%s' to [%s:%d]\n", domain, serverip, port);
        socket_send_domain(serverip, port, domain);
        printf("\n");
    }

    iniparser_freedict(ini);
}

int socket_send_domain(char *serverip, int port, char *msg)
{
    int                     conn_fd = -1;
    int                     rv = -1;    
    struct sockaddr_in      serv_addr;

    struct sockaddr_in      addr;
    struct timeval          timeo = {6, 0};
    socklen_t               len = sizeof(timeo);

    conn_fd = socket(AF_INET, SOCK_STREAM, 0);
    if(conn_fd < 0)
    {
        printf("ERROR: create socket failure: %s\n", strerror(errno));
        return -1;
    }


    memset(&serv_addr, 0, sizeof(serv_addr));
    serv_addr.sin_family = AF_INET;
    serv_addr.sin_port = htons(port);
    inet_aton( serverip, &serv_addr.sin_addr );


    setsockopt(conn_fd, SOL_SOCKET, SO_SNDTIMEO, &timeo, len);

    if( connect(conn_fd, (struct sockaddr *)&serv_addr, sizeof(serv_addr))  < 0)
    {
        printf("ERROR: connect to server [%s:%d] failure: %s\n", serverip, port, strerror(errno));
        goto cleanup;
    }
    
    if( write(conn_fd, msg, strlen(msg)) < 0 )
    {
        printf("ERROR: Write data to server [%s:%d] failure: %s\n", serverip, port, strerror(errno)); 
        goto cleanup;
    }
    printf("ok\n");

    sleep(1);
    
cleanup:
    close(conn_fd);
}