Retrieves the path or URL of an attachment’s attached file.

If the attached file is not present on the local filesystem (usually due to replication plugins),
then the URL of the file is returned if `allow_url_fopen` is supported.

function _load_image_to_edit_path( $attachment_id, $size = 'full' ) {
	$filepath = get_attached_file( $attachment_id );

	if ( $filepath && file_exists( $filepath ) ) {
		if ( 'full' !== $size ) {
			$data = image_get_intermediate_size( $attachment_id, $size );

			if ( $data ) {
				$filepath = path_join( dirname( $filepath ), $data['file'] );

				/**
				 * Filters the path to an attachment's file when editing the image.
				 *
				 * The filter is evaluated for all image sizes except 'full'.
				 *
				 * @since 3.1.0
				 *
				 * @param string       $path          Path to the current image.
				 * @param int          $attachment_id Attachment ID.
				 * @param string|int[] $size          Requested image size. Can be any registered image size name, or
				 *                                    an array of width and height values in pixels (in that order).
				 */
				$filepath = apply_filters( 'load_image_to_edit_filesystempath', $filepath, $attachment_id, $size );
			}
		}
	} elseif ( function_exists( 'fopen' ) && ini_get( 'allow_url_fopen' ) ) {
		/**
		 * Filters the path to an attachment's URL when editing the image.
		 *
		 * The filter is only evaluated if the file isn't stored locally and `allow_url_fopen` is enabled on the server.
		 *
		 * @since 3.1.0
		 *
		 * @param string|false $image_url     Current image URL.
		 * @param int          $attachment_id Attachment ID.
		 * @param string|int[] $size          Requested image size. Can be any registered image size name, or
		 *                                    an array of width and height values in pixels (in that order).
		 */
		$filepath = apply_filters( 'load_image_to_edit_attachmenturl', wp_get_attachment_url( $attachment_id ), $attachment_id, $size );
	}

	/**
	 * Filters the returned path or URL of the current image.
	 *
	 * @since 2.9.0
	 *
	 * @param string|false $filepath      File path or URL to current image, or false.
	 * @param int          $attachment_id Attachment ID.
	 * @param string|int[] $size          Requested image size. Can be any registered image size name, or
	 *                                    an array of width and height values in pixels (in that order).
	 */
	return apply_filters( 'load_image_to_edit_path', $filepath, $attachment_id, $size );
}