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

#include "output.h"
#include "util/http/http.h"
#include "device/buffer.h"
#include "device/buffer_lock.h"

#define PART_BOUNDARY "123456789000000000000987654321"
#define CONTENT_TYPE "image/jpeg"
#define CONTENT_LENGTH "Content-Length"

static const char *const STREAM_HEADER = "HTTP/1.0 200 OK\r\n"
                                         "Access-Control-Allow-Origin: *\r\n"
                                         "Connection: close\r\n"
                                         "Content-Type: multipart/x-mixed-replace;boundary=" PART_BOUNDARY "\r\n"
                                         "\r\n"
                                         "--" PART_BOUNDARY "\r\n";
static const char *const STREAM_PART = "Content-Type: " CONTENT_TYPE "\r\n" CONTENT_LENGTH ": %u\r\n\r\n";
static const char *const STREAM_BOUNDARY = "\r\n"
                                           "--" PART_BOUNDARY "\r\n";

int http_snapshot_buf_part(buffer_lock_t *buf_lock, buffer_t *buf, int frame, FILE *stream)
{
  fprintf(stream, "HTTP/1.1 200 OK\r\n");
  fprintf(stream, "Content-Type: image/jpeg\r\n");
  fprintf(stream, "Content-Length: %zu\r\n", buf->used);
  fprintf(stream, "\r\n");
  fwrite(buf->start, buf->used, 1, stream);
  return 1;
}

void http_snapshot(http_worker_t *worker, FILE *stream)
{
  int n = buffer_lock_write_loop(&snapshot_lock, 1, 0, (buffer_write_fn)http_snapshot_buf_part, stream);

  if (n <= 0) {
    http_500(stream, NULL);
    fprintf(stream, "No snapshot captured yet.\r\n");
  }
}

int http_stream_buf_part(buffer_lock_t *buf_lock, buffer_t *buf, int frame, FILE *stream)
{
  if (!frame && !fputs(STREAM_HEADER, stream)) {
    return -1;
  }
  if (!fprintf(stream, STREAM_PART, buf->used)) {
    return -1;
  }
  if (!fwrite(buf->start, buf->used, 1, stream)) {
    return -1;
  }
  if (!fputs(STREAM_BOUNDARY, stream)) {
    return -1;
  }

  return 1;
}

void http_stream(http_worker_t *worker, FILE *stream)
{
  int n = buffer_lock_write_loop(&stream_lock, 0, 0, (buffer_write_fn)http_stream_buf_part, stream);

  if (n == 0) {
    http_500(stream, NULL);
    fprintf(stream, "No frames.\n");
  } else if (n < 0) {
    fprintf(stream, "Interrupted. Received %d frames", -n);
  }
}