#include "tweetnacl.h"

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

void randombytes(unsigned char * ptr,unsigned int length);

int main() {
	unsigned char sk[crypto_box_SECRETKEYBYTES];
	unsigned char pk[crypto_box_PUBLICKEYBYTES];
	unsigned char sk2[crypto_box_SECRETKEYBYTES];
	unsigned char pk2[crypto_box_PUBLICKEYBYTES];
	unsigned char nonce[crypto_box_NONCEBYTES];

  const int message_len = 1370;
  unsigned char *message = malloc(message_len);
  randombytes(message, message_len);

	randombytes(nonce, crypto_box_NONCEBYTES);

	assert(!crypto_box_keypair(pk, sk));
	assert(!crypto_box_keypair(pk2, sk2));

  unsigned char *plaintext = calloc(1, message_len + crypto_box_ZEROBYTES);
  memcpy(plaintext + crypto_box_ZEROBYTES, message, message_len);

  unsigned char *ciphertext = malloc(message_len + crypto_box_ZEROBYTES);

  assert(!crypto_box(ciphertext, plaintext, message_len + crypto_box_ZEROBYTES,
                     nonce, pk2, sk));

  /* crypto_box leaves some blank padding at the beginning of the
     ciphertext, which we will want to strip when transimitting. */
  for (int i=0; i<crypto_box_BOXZEROBYTES; i++) assert(!ciphertext[i]);

  unsigned char *cipherciphertext = malloc(message_len + 2*crypto_box_ZEROBYTES - crypto_box_BOXZEROBYTES);
  unsigned char *newplaintext = calloc(1, message_len + 2*crypto_box_ZEROBYTES - crypto_box_BOXZEROBYTES);
  memcpy(newplaintext + crypto_box_ZEROBYTES,
         ciphertext + crypto_box_ZEROBYTES,
         message_len + crypto_box_ZEROBYTES);
  assert(!crypto_box(cipherciphertext,
                     newplaintext,
                     message_len + crypto_box_ZEROBYTES,
                     nonce, pk2, sk));

  for (int i=0;i<message_len + crypto_box_ZEROBYTES; i++) {
    printf("%02x == %02x\n", cipherciphertext[i], plaintext[i]);
    if (i >= crypto_box_ZEROBYTES) assert(cipherciphertext[i] == plaintext[i]);
  }
  return 0;
}