/* terminal.h -- */
#ifndef __TERMINAL_H__
#define __TERMINAL_H__

#include "defines.h"    /* COLOR, SCROLLCODE */
#include "retcode.h"
#include "utf8.h"

/* The editor communicates with the display using a high level interface. A
 * "TERM" structure holds useful variables, and indirect pointers to routines
 * that do useful operations. The low level get and put routines are here too.
 * This lets a terminal, in addition to having non standard commands, have
 * funny get and put character code too. The calls might get changed to
 * "termp->t_field" style in the future, to make it possible to run more than
 * one terminal type.
 */
struct terminal {
    const short t_maxrow ;  /* max number of rows allowable         */
    const short t_maxcol ;  /* max number of columns allowable      */
    short t_mrow ;          /* max number of rows displayable       */
    short t_nrow ;          /* current number of rows displayed     */
    short t_mcol ;          /* max number of rows displayable       */
    short t_ncol ;          /* current number of columns displayed  */
    short t_margin;     /* min margin for extended lines */
    short t_scrsiz;     /* size of scroll region "      */
    int t_pause;        /* # times thru update to pause */
    void (*t_open)(void);   /* Open terminal at the start.  */
    void (*t_close)(void);  /* Close terminal at end.       */
    void (*t_kopen)(void);  /* Open keyboard                */
    void (*t_kclose)(void); /* close keyboard               */
    int (*t_getchar)(void); /* Get character from keyboard. */
    int (*t_putchar)( unicode_t) ;  /* Put character to display.    */
    void (*t_flush) (void); /* Flush output buffers.        */
    void (*t_move)(int, int);/* Move the cursor, origin 0.   */
    void (*t_eeol)(void);   /* Erase to end of line.        */
    void (*t_eeop)(void);   /* Erase to end of page.        */
    void (*t_beep)(void);   /* Beep.                        */
    void (*t_rev)(int); /* set reverse video state      */
    int (*t_rez)(char *);   /* change screen resolution     */
#if COLOR
    int (*t_setfor) (); /* set forground color          */
    int (*t_setback) ();    /* set background color         */
#endif
#if     SCROLLCODE
    void (*t_scroll)(int, int,int); /* scroll a region of the screen */
#endif
};

/* TEMPORARY macros for terminal I/O (to be placed in a machine dependant
   place later)
 */

#define TTopen      (*term.t_open)
#define TTclose     (*term.t_close)
#define TTkopen     (*term.t_kopen)
#define TTkclose    (*term.t_kclose)
#define TTgetc      (*term.t_getchar)
#define TTputc      (*term.t_putchar)
#define TTflush     (*term.t_flush)
#define TTmove      (*term.t_move)
#define TTeeol      (*term.t_eeol)
#define TTeeop      (*term.t_eeop)
#define TTbeep      (*term.t_beep)
#define TTrev       (*term.t_rev)
#define TTrez       (*term.t_rez)
#if COLOR
#define TTforg      (*term.t_setfor)
#define TTbacg      (*term.t_setback)
#endif

/* Terminal table defined only in term.c */
extern struct terminal term ;

extern int ttrow ;          /* Row location of HW cursor */
extern int ttcol ;          /* Column location of HW cursor */

extern boolean eolexist ;   /* does clear to EOL exist?     */
extern boolean revexist ;   /* does reverse video exist?    */
extern boolean sgarbf ;     /* State of screen unknown      */

extern char sres[] ;        /* Current screen resolution.   */
                            /* NORMAL, CGA, EGA, VGA    */

#endif
/* end of terminal.h */