bbp_check_for_duplicate( array $post_data = array() )

function bbp_check_for_duplicate( $post_data = array() ) {

	// No duplicate checks for those who can throttle
	if ( current_user_can( 'throttle' ) )
		return true;

	// Define global to use get_meta_sql() and get_var() methods
	global $wpdb;

	// Parse arguments against default values
	$r = bbp_parse_args( $post_data, array(
		'post_author'    => 0,
		'post_type'      => array( bbp_get_topic_post_type(), bbp_get_reply_post_type() ),
		'post_parent'    => 0,
		'post_content'   => '',
		'post_status'    => bbp_get_trash_status_id(),
		'anonymous_data' => false
	), 'check_for_duplicate' );

	// Check for anonymous post
	if ( empty( $r['post_author'] ) && ( !empty( $r['anonymous_data'] ) && !empty( $r['anonymous_data']['bbp_anonymous_email'] ) ) ) {
		$clauses = get_meta_sql( array( array(
			'key'   => '_bbp_anonymous_email',
			'value' => sanitize_email( $r['anonymous_data']['bbp_anonymous_email'] )
		) ), 'post', $wpdb->posts, 'ID' );

		$join    = $clauses['join'];
		$where   = $clauses['where'];
	} else {
		$join    = $where = '';
	}

	// Unslash $r to pass through $wpdb->prepare()
	//
	// @see: http://bbpress.trac.wordpress.org/ticket/2185/
	// @see: http://core.trac.wordpress.org/changeset/23973/
	$r = function_exists( 'wp_unslash' ) ? wp_unslash( $r ) : stripslashes_deep( $r );

	// Prepare duplicate check query
	$query  = $wpdb->prepare( "SELECT ID FROM {$wpdb->posts} {$join} WHERE post_type = %s AND post_status != %s AND post_author = %d AND post_content = %s {$where}", $r['post_type'], $r['post_status'], $r['post_author'], $r['post_content'] );
	$query .= !empty( $r['post_parent'] ) ? $wpdb->prepare( " AND post_parent = %d", $r['post_parent'] ) : '';
	$query .= " LIMIT 1";
	$dupe   = apply_filters( 'bbp_check_for_duplicate_query', $query, $r );

	if ( $wpdb->get_var( $dupe ) ) {
		do_action( 'bbp_check_for_duplicate_trigger', $post_data );
		return false;
	}

	return true;
}