/* Public Domain Curses */

#include <curspriv.h>

RCSID("$Id: kernel.c,v 1.78 2008/07/15 17:13:26 wmcbrine Exp $")

/*man-start**************************************************************

  Name:                                                         kernel

  Synopsis:
        int def_prog_mode(void);
        int def_shell_mode(void);
        int reset_prog_mode(void);
        int reset_shell_mode(void);
        int resetty(void);
        int savetty(void);
        int ripoffline(int line, int (*init)(WINDOW *, int));
        int curs_set(int visibility);
        int napms(int ms);

        int draino(int ms);
        int resetterm(void);
        int fixterm(void);
        int saveterm(void);

  Description:
        def_prog_mode() and def_shell_mode() save the current terminal
        modes as the "program" (in curses) or "shell" (not in curses)
        state for use by the reset_prog_mode() and reset_shell_mode()
        functions.  This is done automatically by initscr().

        reset_prog_mode() and reset_shell_mode() restore the terminal to
        "program" (in curses) or "shell" (not in curses) state.  These
        are done automatically by endwin() and doupdate() after an
        endwin(), so they would normally not be called before these
        functions.

        savetty() and resetty() save and restore the state of the
        terminal modes. savetty() saves the current state in a buffer,
        and resetty() restores the state to what it was at the last call
        to savetty().

        curs_set() alters the appearance of the cursor. A visibility of
        0 makes it disappear; 1 makes it appear "normal" (usually an
        underline) and 2 makes it "highly visible" (usually a block).

        ripoffline() reduces the size of stdscr by one line.  If the
        "line" parameter is positive, the line is removed from the top
        of the screen; if negative, from the bottom. Up to 5 lines can
        be ripped off stdscr by calling ripoffline() repeatedly. The
        function argument, init, is called from within initscr() or
        newterm(), so ripoffline() must be called before either of these
        functions.  The init function receives a pointer to a one-line
        WINDOW, and the width of the window. Calling ripoffline() with a
        NULL init function pointer is an error.

        napms() suspends the program for the specified number of
        milliseconds. draino() is an archaic equivalent.

        resetterm(), fixterm() and saveterm() are archaic equivalents
        for reset_shell_mode(), reset_prog_mode() and def_prog_mode(),
        respectively.

  Return Value:
        All functions return OK on success and ERR on error, except
        curs_set(), which returns the previous visibility.

  Portability                                X/Open    BSD    SYS V
        def_prog_mode                           Y       Y       Y
        def_shell_mode                          Y       Y       Y
        reset_prog_mode                         Y       Y       Y
        reset_shell_mode                        Y       Y       Y
        resetty                                 Y       Y       Y
        savetty                                 Y       Y       Y
        ripoffline                              Y       -      3.0
        curs_set                                Y       -      3.0
        napms                                   Y       Y       Y
        draino                                  -
        resetterm                               -
        fixterm                                 -
        saveterm                                -

**man-end****************************************************************/

#include <string.h>

RIPPEDOFFLINE linesripped[5];
char linesrippedoff = 0;

static struct cttyset
{
    bool been_set;
    SCREEN saved;
} ctty[3];

enum { PDC_SH_TTY, PDC_PR_TTY, PDC_SAVE_TTY };

static void _save_mode(int i)
{
    ctty[i].been_set = TRUE;

    memcpy(&(ctty[i].saved), SP, sizeof(SCREEN));

    PDC_save_screen_mode(i);
}

static int _restore_mode(int i)
{
    if (ctty[i].been_set == TRUE)
    {
        memcpy(SP, &(ctty[i].saved), sizeof(SCREEN));

        if (ctty[i].saved.raw_out)
            raw();

        PDC_restore_screen_mode(i);

        if ((LINES != ctty[i].saved.lines) ||
            (COLS != ctty[i].saved.cols))
            resize_term(ctty[i].saved.lines, ctty[i].saved.cols);

        PDC_curs_set(ctty[i].saved.visibility);

        PDC_gotoyx(ctty[i].saved.cursrow, ctty[i].saved.curscol);
    }

    return ctty[i].been_set ? OK : ERR;
}

int def_prog_mode(void)
{
    PDC_LOG(("def_prog_mode() - called\n"));

    _save_mode(PDC_PR_TTY);

    return OK;
}

int def_shell_mode(void)
{
    PDC_LOG(("def_shell_mode() - called\n"));

    _save_mode(PDC_SH_TTY);

    return OK;
}

int reset_prog_mode(void)
{
    PDC_LOG(("reset_prog_mode() - called\n"));

    _restore_mode(PDC_PR_TTY);
    PDC_reset_prog_mode();

    return OK;
}

int reset_shell_mode(void)
{
    PDC_LOG(("reset_shell_mode() - called\n"));

    _restore_mode(PDC_SH_TTY);
    PDC_reset_shell_mode();

    return OK;
}

int resetty(void)
{
    PDC_LOG(("resetty() - called\n"));

    return _restore_mode(PDC_SAVE_TTY);
}

int savetty(void)
{
    PDC_LOG(("savetty() - called\n"));

    _save_mode(PDC_SAVE_TTY);

    return OK;
}

int curs_set(int visibility)
{
    int ret_vis;

    PDC_LOG(("curs_set() - called: visibility=%d\n", visibility));

    if ((visibility < 0) || (visibility > 2))
        return ERR;

    ret_vis = PDC_curs_set(visibility);

    /* If the cursor is changing from invisible to visible, update
       its position */

    if (visibility && !ret_vis)
        PDC_gotoyx(SP->cursrow, SP->curscol);

    return ret_vis;
}

int napms(int ms)
{
    PDC_LOG(("napms() - called: ms=%d\n", ms));

    if (ms)
        PDC_napms(ms);

    return OK;
}

int ripoffline(int line, int (*init)(WINDOW *, int))
{
    PDC_LOG(("ripoffline() - called: line=%d\n", line));

    if (linesrippedoff < 5 && line && init)
    {
        linesripped[(int)linesrippedoff].line = line;
        linesripped[(int)linesrippedoff++].init = init;

        return OK;
    }

    return ERR;
}

int draino(int ms)
{
    PDC_LOG(("draino() - called\n"));

    return napms(ms);
}

int resetterm(void)
{
    PDC_LOG(("resetterm() - called\n"));

    return reset_shell_mode();
}

int fixterm(void)
{
    PDC_LOG(("fixterm() - called\n"));

    return reset_prog_mode();
}

int saveterm(void)
{
    PDC_LOG(("saveterm() - called\n"));

    return def_prog_mode();
}