/* vview.c - drawing for the c64 vim clone: scroll, rows, status row. */

extern char *bfr;
extern unsigned blen;
extern unsigned lptr[];
extern int nlines, cy, cx, top, leftcol, mode, dirty;
extern char *note;
extern char fname[];
extern char ybuf[];
extern int ylen, yok;
extern int redraw;

/* decimal of v into t at p, returns the position after it */
dnum(t, p, v)
char *t;
int p, v;
{
    char d[6];
    int n;

    n = 0;
    if (v == 0) {
        t[p++] = 48;
        return p;
    }
    while (v > 0 && n < 5) {
        d[n++] = 48 + (v % 10);
        v = v / 10;
    }
    while (n > 0) t[p++] = d[--n];
    return p;
}

/* bring the cursor back into view */
scroll()
{
    if (cy < top) top = cy;
    if (cy > top + 23) top = cy - 23;
    if (top < 0) top = 0;
    if (cx < leftcol) leftcol = cx;
    if (cx > leftcol + 39) leftcol = cx - 39;
    if (leftcol < 0) leftcol = 0;
    return 0;
}

/* the status row: message, mode or name on the left; modified flag; line/total */
dstat()
{
    char t[40];
    char *s;
    int i, n, p;

    if (note != 0) s = note;
    else if (mode) s = "-- insert --";
    else if (fname[0] == 0) s = "[no name]";
    else s = fname;

    n = 0;
    for (i = 0; s[i] && i < 26; i++) t[n++] = s[i];
    while (n < 28) t[n++] = 32;
    if (dirty) t[n++] = 43;                     /* + */
    else t[n++] = 32;
    while (n < 31) t[n++] = 32;
    p = dnum(t, n, cy + 1);
    t[p++] = 47;                                /* / */
    p = dnum(t, p, nlines);

    mlrow((unsigned) t, p, 1984, 255, 128);     /* row 24 = $0400 + 960, reverse */
    return 0;
}

/* what the screen showed last time, so a key that only moves the cursor
   repaints two rows instead of 24 */
int ltop, lleft, lcy;

/* repaint what changed, then the status row. redraw is raised by the editing
   code: 1 = the cursor line changed, 2 = lines moved, repaint everything.
   (no double bar: power c cannot type it, see NOTES.md) */
dall()
{
    int crow, ccol, orow, full;

    crow = cy - top;
    ccol = cx - leftcol;
    full = 0;
    if (redraw == 2) full = 1;
    if (top != ltop) full = 1;
    if (leftcol != lleft) full = 1;
    if (full) {
        mlscr(0, 23, crow, ccol);               /* one call paints 24 rows */
    } else {
        orow = lcy - top;                       /* take the cursor off its old row */
        if (orow != crow && orow >= 0 && orow < 24) mlscr(orow, orow, crow, ccol);
        mlscr(crow, crow, crow, ccol);
    }
    ltop = top;
    lleft = leftcol;
    lcy = cy;
    redraw = 0;
    dstat();
    return 0;
}

/* end of vview.c */