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

#include "ql_type.h"
#include "ql_func.h"
#include "ql_application.h"

#include "ql_data_call.h"
#include "ql_xlat.h"

#include "ip6_addr.h"
#include "sockets.h"

/* ========= Minimal config ========= */
#define PROFILE_IDX       1
#define IP_VER_V6         1               /* 1 = IPv6 only */
#define APN_NAME          "diginet"        /* DigiNet */

/* Send 1 UDP packet to an IPv4 destination (no reply needed) */
#define DST_IPV4_HEX      0x08080808       /* 8.8.8.8 */
#define DST_PORT          12345

static void print_ipv6_bytes(const unsigned char *p16)
{
    for (int i = 0; i < 16; i++)
    {
        printf("%02X", p16[i]);
        if (i != 15) printf(":");
    }
    printf("\r\n");
}

static int start_ipv6_pdp(void)
{
    int ret;
    struct ql_data_call_info info;

    /* Give SIM/RF some time */
    ql_rtos_task_sleep_ms(5000);

    printf("[XLAT] wait network register...\r\n");
    ret = ql_network_register_wait(180);
    printf("[XLAT] network register ret=%d\r\n", ret);
    if (ret != 0) return -1;

    /* Set default netif for this profile (good practice) */
    (void)ql_set_lwip_netif_default_by_profile_idx(PROFILE_IDX);

    printf("[XLAT] start IPv6 PDP: profile=%d apn=%s\r\n", PROFILE_IDX, APN_NAME);
    ret = ql_start_data_call(PROFILE_IDX, IP_VER_V6, (char *)APN_NAME, NULL, NULL, 0);
    printf("[XLAT] ql_start_data_call ret=%d\r\n", ret);
    if (ret != 0) return -2;

    memset(&info, 0, sizeof(info));
    ret = ql_get_data_call_info(PROFILE_IDX, IP_VER_V6, &info);
    printf("[XLAT] ql_get_data_call_info ret=%d\r\n", ret);
    if (ret != 0) return -3;

    printf("[XLAT] IPv6 addr = ");
    print_ipv6_bytes((unsigned char *)info.v6.addr.ip.s6_addr);

    return 0;
}

static int enable_clat_min(void)
{
    int ret;
    int prefix_len;
    ip6_addr_t prefix;

    printf("[XLAT] clat_is_enable(before)=%d\r\n", (int)ql_clat_is_enable());

    prefix_len = ql_get_clat_prefix_len();
    printf("[XLAT] nat64 prefix_len=%d\r\n", prefix_len);

    memset(&prefix, 0, sizeof(prefix));
    ret = ql_get_clat_prefix_addr(&prefix);
    printf("[XLAT] get_prefix_addr ret=%d\r\n", ret);

    if (prefix_len <= 0 || prefix_len > 128)
    {
        printf("[XLAT] invalid prefix_len, stop\r\n");
        return -1;
    }

    ret = ql_set_clat(TRUE, &prefix, (char)prefix_len);
    printf("[XLAT] ql_set_clat ret=%d\r\n", ret);

    printf("[XLAT] clat_is_enable(after)=%d\r\n", (int)ql_clat_is_enable());
    return ret;
}

static int send_one_ipv4_udp(void)
{
    int fd;
    struct sockaddr_in dst;
    const char payload[] = "XLAT_MIN_PROOF";

    fd = socket(AF_INET, SOCK_DGRAM, 0);
    if (fd < 0)
    {
        printf("[XLAT] socket(AF_INET,UDP) fail\r\n");
        return -1;
    }

    memset(&dst, 0, sizeof(dst));
    dst.sin_family = AF_INET;
    dst.sin_port   = htons(DST_PORT);
    dst.sin_addr.s_addr = htonl(DST_IPV4_HEX);

    printf("[XLAT] send UDP via IPv4 socket to %d.%d.%d.%d:%d\r\n",
           (DST_IPV4_HEX >> 24) & 0xFF,
           (DST_IPV4_HEX >> 16) & 0xFF,
           (DST_IPV4_HEX >>  8) & 0xFF,
           (DST_IPV4_HEX >>  0) & 0xFF,
           DST_PORT);

    int n = sendto(fd, payload, (int)sizeof(payload) - 1, 0,
                   (struct sockaddr *)&dst, sizeof(dst));

    if (n > 0) printf("[XLAT] sendto OK, bytes=%d\r\n", n);
    else       printf("[XLAT] sendto FAIL, ret=%d\r\n", n);

    /* IMPORTANT: use close(), not closesocket() */
    close(fd);
    return (n > 0) ? 0 : -2;
}

static void xlat_min_task(void *arg)
{
    (void)arg;

    printf("\r\n[XLAT] ===== XLAT MIN UDP PROOF START =====\r\n");

    if (start_ipv6_pdp() == 0)
    {
        if (enable_clat_min() == 0)
        {
            int ret = send_one_ipv4_udp();
            if (ret == 0)
                printf("[XLAT] >>> MIN PASS (local): IPv4 UDP send succeeded on IPv6 PDP\r\n");
            else
                printf("[XLAT] >>> MIN FAIL: send failed\r\n");
        }
        else
        {
            printf("[XLAT] >>> FAIL: enable CLAT failed\r\n");
        }
    }
    else
    {
        printf("[XLAT] >>> FAIL: IPv6 PDP/network not ready\r\n");
    }

    printf("[XLAT] ===== XLAT MIN UDP PROOF END =====\r\n\r\n");
}

/* Register app at global scope */
//application_init(xlat_min_task, "xlat_min", 10, 0);