#include <mongoc/mongoc.h>

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

int
main(int argc, char *argv[])
{
   const char *uri_string = "mongodb://localhost:27017/?appname=new-gridfs-example";
   mongoc_client_t *client;
   mongoc_database_t *db;
   mongoc_stream_t *file_stream;
   mongoc_gridfs_bucket_t *bucket;
   mongoc_cursor_t *cursor;
   bson_t filter;
   bool res;
   bson_value_t file_id;
   bson_error_t error;
   const bson_t *doc;
   char *str;
   mongoc_init();

   if (argc != 3) {
      fprintf(stderr, "usage: %s SOURCE_FILE_PATH FILE_COPY_PATH\n", argv[0]);
      return EXIT_FAILURE;
   }

   /* 1. Make a bucket. */
   client = mongoc_client_new(uri_string);
   db = mongoc_client_get_database(client, "test");
   bucket = mongoc_gridfs_bucket_new(db, NULL, NULL, &error);
   if (!bucket) {
      printf("Error creating gridfs bucket: %s\n", error.message);
      return EXIT_FAILURE;
   }

   /* 2. Insert a file.  */
   file_stream = mongoc_stream_file_new_for_path(argv[1], O_RDONLY, 0);
   res = mongoc_gridfs_bucket_upload_from_stream(bucket, "my-file", file_stream, NULL, &file_id, &error);
   if (!res) {
      printf("Error uploading file: %s\n", error.message);
      return EXIT_FAILURE;
   }

   mongoc_stream_close(file_stream);
   mongoc_stream_destroy(file_stream);

   /* 3. Download the file in GridFS to a local file. */
   file_stream = mongoc_stream_file_new_for_path(argv[2], O_CREAT | O_RDWR, 0);
   if (!file_stream) {
      perror("Error opening file stream");
      return EXIT_FAILURE;
   }

   res = mongoc_gridfs_bucket_download_to_stream(bucket, &file_id, file_stream, &error);
   if (!res) {
      printf("Error downloading file to stream: %s\n", error.message);
      return EXIT_FAILURE;
   }
   mongoc_stream_close(file_stream);
   mongoc_stream_destroy(file_stream);

   /* 4. List what files are available in GridFS. */
   bson_init(&filter);
   cursor = mongoc_gridfs_bucket_find(bucket, &filter, NULL);

   while (mongoc_cursor_next(cursor, &doc)) {
      str = bson_as_canonical_extended_json(doc, NULL);
      printf("%s\n", str);
      bson_free(str);
   }

   /* 5. Delete the file that we added. */
   res = mongoc_gridfs_bucket_delete_by_id(bucket, &file_id, &error);
   if (!res) {
      printf("Error deleting the file: %s\n", error.message);
      return EXIT_FAILURE;
   }

   /* 6. Cleanup. */
   mongoc_stream_close(file_stream);
   mongoc_stream_destroy(file_stream);
   mongoc_cursor_destroy(cursor);
   bson_destroy(&filter);
   mongoc_gridfs_bucket_destroy(bucket);
   mongoc_database_destroy(db);
   mongoc_client_destroy(client);
   mongoc_cleanup();

   return EXIT_SUCCESS;
}
