#include <sys/types.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <netinet/in.h>
#include <net/if.h>
#include <net/if_arp.h>
#include <stdio.h>
#include <errno.h>
#include <fcntl.h>
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <netdb.h>

#include "rpc.h"
#include "ipconfig.h"

/* call ioctl system call */
ret_code if_ioctl(unsigned long request, caddr_t ifreq, int *ret)
{
    int sock;
    int err = 0;

    if(ret)
    {
        *ret = 0;
    }

    sock = socket(AF_INET, SOCK_DGRAM, 0);
    if (sock < 0) 
    {
        rpc_log_error("Cannot create UDP socket");
        return RET_SOCKERR;
    }
    if ((err = ioctl(sock, request, ifreq)) < 0)
    {
        rpc_log_error("Ioctl error: %s\n", strerror(errno));

    }
    
    close(sock);

    if (err < 0) 
    {
        if(ret)
        {
            *ret = err;
        }
        return RET_SYSERR;
    }

    return RET_OK;
}


/* Set a certain interface flag. */
static int if_set_flag(char *ifname, short flag, int *code)
{
    struct ifreq ifr = {0};
    ret_code ret = RET_OK;
    
    strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name) - 1);

    ret = if_ioctl(SIOCGIFFLAGS, &ifr, code);
    ASSERT_RET(ret);

    strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name) - 1);
    ifr.ifr_flags |= flag;

    ret = if_ioctl(SIOCSIFFLAGS, &ifr, code);
    ASSERT_RET(ret);
    
    return ret;
}


/* Clear a certain interface flag. */
static int if_clear_flag(char *ifname, short flag,  int *code)
{
    struct ifreq ifr = {0};
    ret_code ret;

    safe_strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name) - 1);

    ret = if_ioctl(SIOCGIFFLAGS, &ifr, code);
    ASSERT_RET(ret);
     
    safe_strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name) - 1);
    ifr.ifr_flags &= ~flag;

    ret = if_ioctl(SIOCSIFFLAGS, &ifr)
    ASSERT_RET(ret);

    return ret;
}

ret_code if_set_prefix(ip_config_t *ip_conf,  int *code)
{
    ret_code ret;
    struct ifreq ifreq = {0};
    struct sockaddr_in addr;
    struct sockaddr_in mask;

    strncpy(ifreq.ifr_name, ip_conf->ifname, sizeof(ifreq.ifr_name) - 1);
    addr.sin_addr   = ip_conf->prefix;
    addr.sin_family = ip_conf->family;
    memcpy(&ifreq.ifr_addr, &addr, sizeof(struct sockaddr_in));

    ret = if_ioctl(SIOCSIFADDR, (caddr_t)&ifreq, code);
    ASSERT_RET(ret);

    if(ip_conf->prefix.s_addr != 0)
    {
        masklen2ip(ip_conf->prefixlen, &mask.sin_addr);
        mask.sin_family = ip_conf->family;
        memcpy(&ifreq.ifr_netmask, &mask, sizeof(struct sockaddr_in));
        
        ret = if_ioctl(SIOCSIFNETMASK, (caddr_t)&ifreq, code);
        ASSERT_RET(ret);
    }


    return RET_OK;
}

ret_code if_get_prefix_all(pointer output, int *output_len, int *code)
{    
    struct ifreq ifreq[MAX_IF_NUM];    
    struct sockaddr_in *addr;    
    struct ifreq netmask;
    ip_config_t *ip_conf;
    struct ifconf ifc;    
    int if_count = 0;
    ret_code ret;
    int mask_ret;
    int i;

    memset(&ifc,   0, sizeof(struct ifconf));
    memset(&ifreq, 0, MAX_IF_NUM * sizeof(struct ifreq));
    
    ifc.ifc_len = MAX_IF_NUM * sizeof(struct ifreq);
    ifc.ifc_buf = (char *)ifreq;

    ret = if_ioctl(SIOCGIFCONF, (caddr_t)&ifc, code);
    ASSERT_RET(ret);

    if_count = ifc.ifc_len / (sizeof(struct ifreq));

    rpc_log_info("if num is %d\n", if_count);
    
    if((if_count * sizeof(ip_config_t) > CM_BUFF_SIZE)
        || (if_count == 0))
    {
        ret = RET_NOMEM;
        ASSERT_RET(ret);
    }
        
    ip_conf = rpc_new(ip_config_t, MAX_IF_NUM);
    if(ip_conf == NULL)
    {
        return RET_NOMEM;
    }
    memset(ip_conf, 0, MAX_IF_NUM * sizeof(ip_config_t));

    for(i = 0; i < if_count; i++)
    {
        rpc_log_info("get interface %s info\n", ifreq[i].ifr_name);
        strncpy(ip_conf[i].ifname, ifreq[i].ifr_name, INTERFACE_NAMSIZ - 1);
        ip_conf[i].family = AF_INET;
        ip_conf[i].prefix = ((struct sockaddr_in *)&(ifreq[i].ifr_addr))->sin_addr;

        memset(&netmask, 0, sizeof(netmask));
        strncpy(netmask.ifr_name, ifreq[i].ifr_name, sizeof(netmask.ifr_name) - 1);
        
        ret = if_ioctl(SIOCGIFNETMASK, (caddr_t)&netmask, &mask_ret);
        ASSERT_RET_NO(ret);

        addr = ( struct sockaddr_in * )&(netmask.ifr_netmask );
        ip_conf[i].prefixlen = ip_masklen(addr->sin_addr);
    }

    ip_config_format_json_array(CM_CONFIG_GET, ip_conf, if_count, output, output_len);
    
    rpc_free(ip_conf);
    return RET_OK;
}

ret_code if_get_prefix(ip_config_t *ip_conf, int *code)
{
    struct sockaddr_in *addr;
    struct ifreq netmask;    
    struct ifreq ifreq;
    ret_code ret = RET_OK;
    int mask_ret;
    int i;

    if(ip_conf->family != AF_INET)
    {
        ret = RET_INPUTERR;
    }
    
    ASSERT_RET(ret);
    
    memset(&ifreq, 0, sizeof(struct ifreq));
    
    rpc_log_info("get interface %s info\n", ip_conf->ifname);

    strncpy(ifreq.ifr_name, ip_conf->ifname, sizeof(ifreq.ifr_name) - 1);

    ret = if_ioctl(SIOCGIFADDR, (caddr_t)&ifreq, code);
    ASSERT_RET(ret);
    
    
    ip_conf->prefix = ((struct sockaddr_in *)&(ifreq.ifr_addr))->sin_addr;

    memset(&ifreq, 0, sizeof(ifreq));
    strncpy(ifreq.ifr_name, ip_conf->ifname, sizeof(ifreq.ifr_name) - 1);
    
    ret = if_ioctl(SIOCGIFNETMASK, (caddr_t)&ifreq, &mask_ret);
    ASSERT_RET_NO(ret);

    addr =  ( struct sockaddr_in * )&(ifreq.ifr_netmask);
    ip_conf->prefixlen = ip_masklen(addr->sin_addr);

    return ret;
}

ret_code if_set_up(char *ifname, int *code)
{
    return if_set_flag(ifname, (IFF_UP | IFF_RUNNING),  code);
}

ret_code if_set_down(char *ifname, int *code)
{
    return if_clear_flag(ifname, IFF_UP,  code);
}