#include <esp_wifi_types.h>
#include <esp_wifi.h>
#include <esp_log.h>
#include <fcntl.h>
#include <sys/socket.h>

#include "httpd_utils/fd_to_ipv4.h"

static const char *TAG = "fd2ipv4";

/**
 * Get IP address for a FD
 *
 * @param fd
 * @param[out] ipv4
 * @return success
 */
esp_err_t fd_to_ipv4(int fd, in_addr_t *ipv4)
{
    struct sockaddr_in6 addr;
    size_t len = sizeof(addr);
    int rv = getpeername(fd, (struct sockaddr *) &addr, &len);
    if (rv != 0) {
        ESP_LOGE(TAG, "Failed to get IP addr for fd %d", fd);
        return ESP_FAIL;
    }

    uint32_t client_addr = 0;
    if (addr.sin6_family == AF_INET6) {
        // this would fail in a real ipv6 network
        // with ipv4 the addr is simply in the last ipv6 byte
        struct sockaddr_in6 *s = &addr;
        client_addr = s->sin6_addr.un.u32_addr[3];
    }
    else {
        struct sockaddr_in *s = (struct sockaddr_in *) &addr;
        client_addr = s->sin_addr.s_addr;
    }

    *ipv4 = client_addr;
    return ESP_OK;
}