/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright (c) 1989, 2010, Oracle and/or its affiliates. All rights reserved.
 */

/*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/*        All Rights Reserved   */


/* Copyright (c) 1981 Regents of the University of California */

#include "ex.h"
#include "ex_tty.h"
#include "ex_vis.h"

/*
 * Routines to adjust the window, showing specified lines
 * in certain positions on the screen, and scrolling in both
 * directions.  Code here is very dependent on mode (open versus visual).
 */

/*
 * Move in a nonlocal way to line addr.
 * If it isn't on screen put it in specified context.
 * New position for cursor is curs.
 * Like most routines here, we vsave().
 */
void
vmoveto(addr, curs, context)
        line *addr;
        unsigned char *curs;
        unsigned char context;
{

        markit(addr);
        vsave();
        vjumpto(addr, curs, context);
}

/*
 * Vjumpto is like vmoveto, but doesn't mark previous
 * context or save linebuf as current line.
 */
void
vjumpto(line *addr, unsigned char *curs, unsigned char context)
{

        noteit(0);
        if (context != 0)
                vcontext(addr, context);
        else
                vshow(addr, NOLINE);
        noteit(1);
        vnline(curs);
}

/*
 * Go up or down cnt (negative is up) to new position curs.
 */
void
vupdown(int cnt, unsigned char *curs)
{

        if (cnt > 0)
                vdown(cnt, 0, 0);
        else if (cnt < 0)
                vup(-cnt, 0, 0);
        if (vcnt == 0)
                vrepaint(curs);
        else
                vnline(curs);
}

/*
 * Go up cnt lines, afterwards preferring to be ind
 * logical lines from the top of the screen.
 * If scroll, then we MUST use a scroll.
 * Otherwise clear and redraw if motion is far.
 */
void
vup(int cnt, int ind, bool scroll)
{
        int i, tot;

        if (dot == one) {
                (void) beep();
                return;
        }
        vsave();
        i = lineDOT() - 1;
        if (cnt > i) {
                ind -= cnt - i;
                if (ind < 0)
                        ind = 0;
                cnt = i;
        }
        if (!scroll && cnt <= vcline) {
                vshow(dot - cnt, NOLINE);
                return;
        }
        cnt -= vcline, dot -= vcline, vcline = 0;
        if (hold & HOLDWIG)
                goto contxt;
        if (state == VISUAL && !insert_line && !scroll_reverse &&
            cnt <= WTOP - ZERO && vfit(dot - cnt, cnt) <= WTOP - ZERO)
                goto okr;
        tot = WECHO - WTOP;
        if (state != VISUAL || (!insert_line && !scroll_reverse) || (!scroll && (cnt > tot || vfit(dot - cnt, cnt) > tot / 3 + 1))) {
                if (ind > basWLINES / 2)
                        ind = basWLINES / 3;
contxt:
                vcontext(dot + ind - cnt, '.');
                return;
        }
okr:
        vrollR(cnt);
        if (scroll) {
                vcline += ind, dot += ind;
                if (vcline >= vcnt)
                        dot -= vcline - vcnt + 1, vcline = vcnt - 1;
                getDOT();
        }
}

/*
 * Like vup, but scrolling down.
 */
void
vdown(int cnt, int ind, bool scroll)
{
        int i, tot;

        if (dot == dol) {
                (void) beep();
                return;
        }
        vsave();
        i = dol - dot;
        if (cnt > i) {
                ind -= cnt - i;
                if (ind < 0)
                        ind = 0;
                cnt = i;
        }
        i = vcnt - vcline - 1;
        if (!scroll && cnt <= i) {
                vshow(dot + cnt, NOLINE);
                return;
        }
        cnt -= i, dot += i, vcline += i;
        if (hold & HOLDWIG)
                goto dcontxt;
        if (!scroll) {
                tot = WECHO - WTOP;
                if (state != VISUAL || cnt - tot > 0 || vfit(dot, cnt) > tot / 3 + 1) {
dcontxt:
                        vcontext(dot + cnt, '.');
                        return;
                }
        }
        if (cnt > 0)
                vroll(cnt);
        if (state == VISUAL && scroll) {
                vcline -= ind, dot -= ind;
                if (vcline < 0)
                        dot -= vcline, vcline = 0;
                getDOT();
        }
}

/*
 * Show line addr in context where on the screen.
 * Work here is in determining new top line implied by
 * this placement of line addr, since we always draw from the top.
 */
void
vcontext(line *addr, unsigned char where)
{
        line *top;

        getaline(*addr);
        if (state != VISUAL)
                top = addr;
        else switch (where) {

        case '^':
                addr = vback(addr, basWLINES - vdepth());
                getaline(*addr);
                /* FALLTHROUGH */

        case '-':
                top = vback(addr, basWLINES - vdepth());
                getaline(*addr);
                break;

        case '.':
                top = vback(addr, basWLINES / 2 - vdepth());
                getaline(*addr);
                break;

        default:
                top = addr;
                break;
        }
        if (state == ONEOPEN && LINE(0) == WBOT)
                vup1();
        vcnt = vcline = 0;
        vclean();
        if (state == CRTOPEN)
                vup1();
        vshow(addr, top);
}

/*
 * Get a clean line.  If we are in a hard open
 * we may be able to reuse the line we are on
 * if it is blank.  This is a real win.
 */
void
vclean(void)
{

        if (state != VISUAL && state != CRTOPEN) {
                destcol = 0;
                if (!ateopr())
                        vup1();
                vcnt = 0;
        }
}

/*
 * Show line addr with the specified top line on the screen.
 * Top may be 0; in this case have vcontext compute the top
 * (and call us recursively).  Eventually, we clear the screen
 * (or its open mode equivalent) and redraw.
 */
void
vshow(line *addr, line *top)
{
#ifndef CBREAK
        bool fried = 0;
#endif
        int cnt = addr - dot;
        int i = vcline + cnt;
        short oldhold = hold;

        if (state != HARDOPEN && state != ONEOPEN && i >= 0 && i < vcnt) {
                dot = addr;
                getDOT();
                vcline = i;
                return;
        }
        if (state != VISUAL) {
                dot = addr;
                vopen(dot, WBOT);
                return;
        }
        if (top == 0) {
                vcontext(addr, '.');
                return;
        }
        dot = top;
#ifndef CBREAK
        if (vcookit(2))
                fried++, vcook();
#endif
        oldhold = hold;
        hold |= HOLDAT;
        vclear();
        vreset(0);
        vredraw(WTOP);
        /* error if vcline >= vcnt ! */
        vcline = addr - top;
        dot = addr;
        getDOT();
        hold = oldhold;
        vsync(LASTLINE);
#ifndef CBREAK
        if (fried)
                flusho(), vraw();
#endif
}

/*
 * reset the state.
 * If inecho then leave us at the beginning of the echo
 * area;  we are called this way in the middle of a :e escape
 * from visual, e.g.
 */
void
vreset(bool inecho)
{

        vcnt = vcline = 0;
        WTOP = basWTOP;
        WLINES = basWLINES;
        if (inecho)
                splitw = 1, vgoto(WECHO, 0);
}

/*
 * Starting from which line preceding tp uses almost (but not more
 * than) cnt physical lines?
 */
line *
vback(tp, cnt)
        int cnt;
        line *tp;
{
        int d;

        if (cnt > 0)
                for (; tp > one; tp--) {
                        getaline(tp[-1]);
                        d = vdepth();
                        if (d > cnt)
                                break;
                        cnt -= d;
                }
        return (tp);
}

/*
 * How much scrolling will it take to roll cnt lines starting at tp?
 */
int
vfit(line *tp, int cnt)
{
        int j;

        j = 0;
        while (cnt > 0) {
                cnt--;
                getaline(tp[cnt]);
                j += vdepth();
        }
        if (tp > dot)
                j -= WBOT - LASTLINE;
        return (j);
}

/*
 * Roll cnt lines onto the screen.
 */
void
vroll(int cnt)
{
#ifndef CBREAK
        bool fried = 0;
#endif
        short oldhold = hold;

#ifdef ADEBUG
        if (trace)
                tfixnl(), fprintf(trace, "vroll(%d)\n", cnt);
#endif
        if (state != VISUAL)
                hold |= HOLDAT|HOLDROL;
        if (WBOT == WECHO) {
                vcnt = 0;
                if (state == ONEOPEN)
                        vup1();
        }
#ifndef CBREAK
        if (vcookit(cnt))
                fried++, vcook();
#endif
        for (; cnt > 0 && Peekkey != ATTN; cnt--) {
                dot++, vcline++;
                vopen(dot, LASTLINE);
                vscrap();
        }
        hold = oldhold;
        if (state == HARDOPEN)
                sethard();
        vsyncCL();
#ifndef CBREAK
        if (fried)
                flusho(), vraw();
#endif
}

/*
 * Roll backwards (scroll up).
 */
void
vrollR(int cnt)
{
        bool fried = 0;
        short oldhold = hold;

#ifdef ADEBUG
        if (trace)
                tfixnl(), fprintf(trace, "vrollR(%d), dot=%d\n", cnt, lineDOT());
#endif
#ifndef CBREAK
        if (vcookit(cnt))
                fried++, vcook();
#endif
        if (WBOT == WECHO)
                vcnt = 0;
        heldech = 0;
        hold |= HOLDAT|HOLDECH;
        for (; cnt > 0 && Peekkey != ATTN; cnt--) {
                dot--;
                vopen(dot, WTOP);
                vscrap();
        }
        hold = oldhold;
        if (heldech)
                vclrech(0);
        vsync(LINE(vcnt-1));
#ifndef CBREAK
        if (fried)
                flusho(), vraw();
#endif
}

/*
 * Go into cooked mode (allow interrupts) during
 * a scroll if we are at less than 1200 baud and not
 * a 'vi' command, of if we are in a 'vi' command and the
 * scroll is more than 2 full screens.
 *
 * BUG:         An interrupt during a scroll in this way
 *              dumps to command mode.
 */
int
vcookit(int cnt)
{

        return (cnt > 1 && (ospeed < B1200 && !initev || cnt > lines * 2));
}

/*
 * Determine displayed depth of current line.
 */
int
vdepth(void)
{
        int d;

        d = (column(NOSTR) + WCOLS - 1 + (Putchar == listchar) + insert_null_glitch) / WCOLS;
#ifdef ADEBUG
        if (trace)
                tfixnl(), fprintf(trace, "vdepth returns %d\n", d == 0 ? 1 : d);
#endif
        return (d == 0 ? 1 : d);
}

/*
 * Move onto a new line, with cursor at position curs.
 */
void
vnline(unsigned char *curs)
{
        unsigned char *owcursor;
        int j;
        if (curs) {
                if(curs >= strend(linebuf)) {
                        if(!*linebuf)
                                wcursor = linebuf;
                        else {
                                wcursor = strend(linebuf);
                                wcursor = lastchr(linebuf, wcursor);
                        }
                } else {
                        owcursor = wcursor = curs;
                        j = wcursor - linebuf;
                        for(wcursor = linebuf; wcursor - linebuf < j; ) {
                                owcursor = wcursor;
                                wcursor = nextchr(wcursor);
                        }
                        if(wcursor - linebuf > j)
                                wcursor = owcursor;
                }

        } else if (vmoving)
                wcursor = vfindcol(vmovcol);
        else
                wcursor = vskipwh(linebuf);
        cursor = linebuf;
        (void) vmove();
}