DEFINITION MODULE Term ;

(* Screen/keyboard layer for the TP3 shell.
   Implements raw keyboard input via POSIX termios and paints the
   character screen using ANSI escape sequences. *)

PROCEDURE Open ;
(* switch terminal to raw mode, clear screen *)

PROCEDURE Close ;
(* restore terminal state *)

PROCEDURE ClrScr ;
(* home cursor and clear the whole screen *)

PROCEDURE GotoXY (row, col : CARDINAL) ;
(* position the cursor, 1-based (row, col) *)

PROCEDURE PutCh (ch : CHAR) ;

PROCEDURE PutStr (s : ARRAY OF CHAR) ;

PROCEDURE PutCard (n : CARDINAL) ;
(* decimal, no leading zeros (0 -> "0") *)

PROCEDURE PutLongCard (n : LONGCARD) ;

PROCEDURE ScrnWide (n : CARDINAL) ;
(* write n spaces *)

PROCEDURE Marked ;   (* switch to highlighted attribute (command letters) *)
PROCEDURE Normal ;   (* back to normal attribute *)

PROCEDURE GetCh (VAR ch : CHAR) ;
(* blocking read of a single raw key *)

PROCEDURE Avail () : BOOLEAN ;
(* true if a key is already waiting (non-blocking) *)

PROCEDURE GetKey (VAR ch : CHAR) ;
(* read one byte if available, else ch := 0C *)

PROCEDURE Beep ;

END Term.