package syncapi

import (
	"fmt"

	"github.com/dariuszjaniak/warp/server/internal/matrix/id"
)

// The component's errors are plain wrapped sentinels rather than HTTP
// errors, the same as the roomserver's: this package is called from the
// Client-Server handlers and, later, from the application service API, and
// a component that returned HTTP statuses would be deciding something that
// is not its to decide. The handler maps them; see clientapi.syncError.

// errForbiddenf is a refusal the caller is told the reason for.
//
// The reason is passed through to the client on purpose, as it is in the
// roomserver: "M_FORBIDDEN" on its own sends a user to their operator and
// the operator to the logs, and nothing in these messages is anything the
// caller could not work out from the room's state.
func errForbiddenf(format string, args ...any) error {
	return fmt.Errorf("%w: %s", ErrForbidden, fmt.Sprintf(format, args...))
}

// errInvalidParamf is a request parameter this server will not accept.
func errInvalidParamf(format string, args ...any) error {
	return fmt.Errorf("%w: %s", ErrInvalidParam, fmt.Sprintf(format, args...))
}

// errInvalidTokenf is a ?since= or ?from= that could not be read.
func errInvalidTokenf(format string, args ...any) error {
	return fmt.Errorf("%w: %s", ErrInvalidToken, fmt.Sprintf(format, args...))
}

// localpartOf returns the localpart of a user ID of this server.
func (s *API) localpartOf(userID string) (string, bool) {
	localpart, serverName, err := id.SplitUserID(userID)
	if err != nil || serverName != s.serverName {
		return "", false
	}
	return localpart, true
}

// isLocal reports whether a user ID belongs to this server.
func (s *API) isLocal(userID string) bool {
	_, ok := s.localpartOf(userID)
	return ok
}