#include "tftp.h"

#include <string.h>
#include <stdio.h>
#include "lwip/mem.h"
#include "lwip/udp.h"
#include "uartPrintf/printf.h"

/* Define this to a server IP string */
#define LWIP_TFTP_EXAMPLE_CLIENT_REMOTEIP "192.168.225.20"


/* Define this to a file to get via tftp client */
#define LWIP_TFTP_EXAMPLE_CLIENT_FILENAME "somfile.txt"


/* Define a base directory for TFTP access
 * ATTENTION: This code does NOT check for sandboxing,
 * i.e. '..' in paths is not checked! */
#define LWIP_TFTP_EXAMPLE_BASE_DIR ""

#define TFTP_PORT 69

static char full_filename[256];

static void * tftp_open_file(const char* fname, u8_t is_write)
{
  snprintf(full_filename, sizeof(full_filename), "%s%s", LWIP_TFTP_EXAMPLE_BASE_DIR, fname);
  full_filename[sizeof(full_filename)-1] = 0;

  if (is_write) {
    return (void*)fopen(full_filename, "wb");
  } else {
    return (void*)fopen(full_filename, "rb");
  }
}

static void* tftp_open(const char* fname, const char* mode, u8_t is_write)
{
  LWIP_UNUSED_ARG(mode);
  return tftp_open_file(fname, is_write);
}

static void tftp_close(void* handle)
{
  fclose((FILE*)handle);
}

static int tftp_read(void* handle, void* buf, int bytes)
{
  int ret = fread(buf, 1, bytes, (FILE*)handle);
  if (ret <= 0) {
    return -1;
  }
  return ret;
}

static int tftp_write(void* handle, struct pbuf* p)
{
  while (p != NULL) {
    if (fwrite(p->payload, 1, p->len, (FILE*)handle) != (size_t)p->len) {
      return -1;
    }
    p = p->next;
  }

  return 0;
}

/* For TFTP client only */
static void tftp_error(void* handle, int err, const char* msg, int size)
{
  char message[100];

  LWIP_UNUSED_ARG(handle);

  memset(message, 0, sizeof(message));
  MEMCPY(message, msg, LWIP_MIN(sizeof(message)-1, (size_t)size));

  printf("TFTP error: %d (%s)", err, message);
}

static const struct tftp_context tftp = {
		  tftp_open,
		  tftp_close,
		  tftp_read,
		  tftp_write,
		  tftp_error
};

void tftp_example_init_client(void)
{
  void *f;
  err_t err;
  ip_addr_t srv;
  int ret = ipaddr_aton(LWIP_TFTP_EXAMPLE_CLIENT_REMOTEIP, &srv);
  if(ret != 1)
  {
	printf("ipaddr_aton failed \r\n");
  }

  err = tftp_init_client(&tftp);
  if(err != ERR_OK)
  {
	  printf("tftp_init_client failed, error : %d \r\n", err);
  }

  f = tftp_open_file(LWIP_TFTP_EXAMPLE_CLIENT_FILENAME, 1);
  if(f == NULL)
  {
	 printf("failed to open file \r\n");
  }

  err = tftp_get(f, &srv, TFTP_PORT, LWIP_TFTP_EXAMPLE_CLIENT_FILENAME, TFTP_MODE_OCTET);
  if(err != ERR_OK)
  {
	  printf("tftp_get failed \r\n");
  }

}