/*      @(#)ttzapple.c  8.1 (Berkeley) 6/6/93   */
/*      $NetBSD: ttzapple.c,v 1.9 2009/04/14 08:50:06 lukem Exp $       */

/*
 * Copyright (c) 1989, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Edward Wang at The University of California, Berkeley.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <stdio.h>
#include "ww.h"
#include "tt.h"
#include "char.h"

/*
zz|zapple|perfect apple:\
        :am:pt:co#80:li#24:le=^H:nd=^F:up=^K:do=^J:\
        :ho=\E0:ll=\E1:cm=\E=%+ %+ :ch=\E<%+ :cv=\E>%+ :\
        :cl=\E4:ce=\E2:cd=\E3:rp=\E@%.%+ :\
        :so=\E+:se=\E-:\
        :dc=\Ec:DC=\EC%+ :ic=\Ei:IC=\EI%+ :\
        :al=\Ea:AL=\EA%+ :dl=\Ed:DL=\ED%+ :\
        :sf=\Ef:SF=\EF%+ :sr=\Er:SR=\ER%+ :cs=\E?%+ %+ :\
        :is=\E-\ET :
*/

#define NCOL            80
#define NROW            24
#define TOKEN_MAX       32

extern short gen_frame[];

        /* for error correction */
int zz_ecc;
int zz_lastc;

        /* for checkpointing */
int zz_sum;

void    zz_checkpoint(void);
void    zz_checksum(char *, int);
void    zz_clear(void);
void    zz_clreol(void);
void    zz_clreos(void);
void    zz_compress(int);
void    zz_delchar(int);
void    zz_delline(int);
void    zz_end(void);
void    zz_insline(int);
void    zz_insspace(int);
void    zz_move(int, int);
void    zz_put_token(int, const char *, int);
void    zz_putc(char);
void    zz_reset(void);
int     zz_rint(char *, int);
void    zz_scroll_down(int);
void    zz_scroll_up(int);
void    zz_setmodes(int);
void    zz_setscroll(int, int);
void    zz_set_token(int, char *, int);
void    zz_start(void);
void    zz_write(const char *, int);

void
zz_setmodes(int new)
{
        if (new & WWM_REV) {
                if ((tt.tt_modes & WWM_REV) == 0)
                        ttesc('+');
        } else
                if (tt.tt_modes & WWM_REV)
                        ttesc('-');
        tt.tt_modes = new;
}

void
zz_insline(int n)
{
        if (n == 1)
                ttesc('a');
        else {
                ttesc('A');
                ttputc(n + ' ');
        }
}

void
zz_delline(int n)
{
        if (n == 1)
                ttesc('d');
        else {
                ttesc('D');
                ttputc(n + ' ');
        }
}

void
zz_putc(char c)
{
        if (tt.tt_nmodes != tt.tt_modes)
                zz_setmodes(tt.tt_nmodes);
        ttputc(c);
        if (++tt.tt_col == NCOL)
                tt.tt_col = 0, tt.tt_row++;
}

void
zz_write(const char *p, int n)
{
        if (tt.tt_nmodes != tt.tt_modes)
                zz_setmodes(tt.tt_nmodes);
        ttwrite(p, n);
        tt.tt_col += n;
        if (tt.tt_col == NCOL)
                tt.tt_col = 0, tt.tt_row++;
}

void
zz_move(int row, int col)
{
        int x;

        if (tt.tt_row == row) {
same_row:
                if ((x = col - tt.tt_col) == 0)
                        return;
                if (col == 0) {
                        ttctrl('m');
                        goto out;
                }
                switch (x) {
                case 2:
                        ttctrl('f');
                        /* FALLTHROUGH */
                case 1:
                        ttctrl('f');
                        goto out;
                case -2:
                        ttctrl('h');
                        /* FALLTHROUGH */
                case -1:
                        ttctrl('h');
                        goto out;
                }
                if ((col & 7) == 0 && x > 0 && x <= 16) {
                        ttctrl('i');
                        if (x > 8)
                                ttctrl('i');
                        goto out;
                }
                ttesc('<');
                ttputc(col + ' ');
                goto out;
        }
        if (tt.tt_col == col) {
                switch (row - tt.tt_row) {
                case 2:
                        ttctrl('j');
                        /* FALLTHROUGH */
                case 1:
                        ttctrl('j');
                        goto out;
                case -2:
                        ttctrl('k');
                        /* FALLTHROUGH */
                case -1:
                        ttctrl('k');
                        goto out;
                }
                if (col == 0) {
                        if (row == 0)
                                goto home;
                        if (row == NROW - 1)
                                goto ll;
                }
                ttesc('>');
                ttputc(row + ' ');
                goto out;
        }
        if (col == 0) {
                if (row == 0) {
home:
                        ttesc('0');
                        goto out;
                }
                if (row == tt.tt_row + 1) {
                        /*
                         * Do newline first to match the sequence
                         * for scroll down and return
                         */
                        ttctrl('j');
                        ttctrl('m');
                        goto out;
                }
                if (row == NROW - 1) {
ll:
                        ttesc('1');
                        goto out;
                }
        }
        /* favor local motion for better compression */
        if (row == tt.tt_row + 1) {
                ttctrl('j');
                goto same_row;
        }
        if (row == tt.tt_row - 1) {
                ttctrl('k');
                goto same_row;
        }
        ttesc('=');
        ttputc(' ' + row);
        ttputc(' ' + col);
out:
        tt.tt_col = col;
        tt.tt_row = row;
}

void
zz_start(void)
{
        ttesc('T');
        ttputc(TOKEN_MAX + ' ');
        ttesc('U');
        ttputc('!');
        zz_ecc = 1;
        zz_lastc = -1;
        ttesc('v');
        ttflush();
        zz_sum = 0;
        zz_setscroll(0, NROW - 1);
        zz_clear();
        zz_setmodes(0);
}

void
zz_reset(void)
{
        zz_setscroll(0, NROW - 1);
        tt.tt_modes = WWM_REV;
        zz_setmodes(0);
        tt.tt_col = tt.tt_row = -10;
}

void
zz_end(void)
{
        ttesc('T');
        ttputc(' ');
        ttesc('U');
        ttputc(' ');
        zz_ecc = 0;
}

void
zz_clreol(void)
{
        ttesc('2');
}

void
zz_clreos(void)
{
        ttesc('3');
}

void
zz_clear(void)
{
        ttesc('4');
        tt.tt_col = tt.tt_row = 0;
}

void
zz_insspace(int n)
{
        if (n == 1)
                ttesc('i');
        else {
                ttesc('I');
                ttputc(n + ' ');
        }
}

void
zz_delchar(int n)
{
        if (n == 1)
                ttesc('c');
        else {
                ttesc('C');
                ttputc(n + ' ');
        }
}

void
zz_scroll_down(int n)
{
        if (n == 1) {
                if (tt.tt_row == NROW - 1)
                        ttctrl('j');
                else
                        ttesc('f');
        } else {
                ttesc('F');
                ttputc(n + ' ');
        }
}

void
zz_scroll_up(int n)
{
        if (n == 1)
                ttesc('r');
        else {
                ttesc('R');
                ttputc(n + ' ');
        }
}

void
zz_setscroll(int top, int bot)
{
        ttesc('?');
        ttputc(top + ' ');
        ttputc(bot + ' ');
        tt.tt_scroll_top = top;
        tt.tt_scroll_bot = bot;
}

int zz_debug = 0;

void
zz_set_token(int t, char *s, int n)
{
        if (tt.tt_nmodes != tt.tt_modes)
                zz_setmodes(tt.tt_nmodes);
        if (zz_debug) {
                char buf[100];
                zz_setmodes(WWM_REV);
                (void) sprintf(buf, "%02x=", t);
                ttputs(buf);
                tt.tt_col += 3;
        }
        ttputc(0x80);
        ttputc(t + 1);
        s[n - 1] |= 0x80;
        ttwrite(s, n);
        s[n - 1] &= ~0x80;
}

void
zz_put_token(int t, const char *s __unused, int n __unused)
{
        if (tt.tt_nmodes != tt.tt_modes)
                zz_setmodes(tt.tt_nmodes);
        if (zz_debug) {
                char buf[100];
                zz_setmodes(WWM_REV);
                (void) sprintf(buf, "%02x>", t);
                ttputs(buf);
                tt.tt_col += 3;
        }
        ttputc(t + 0x81);
}

int
zz_rint(char *p, int n)
{
        int i;
        char *q;

        if (!zz_ecc)
                return n;
        for (i = n, q = p; --i >= 0;) {
                int c = (unsigned char) *p++;

                if (zz_lastc == 0) {
                        switch (c) {
                        case 0:
                                *q++ = 0;
                                zz_lastc = -1;
                                break;
                        case 1:         /* start input ecc */
                                zz_ecc = 2;
                                zz_lastc = -1;
                                wwnreadstat++;
                                break;
                        case 2:         /* ack checkpoint */
                                tt.tt_ack = 1;
                                zz_lastc = -1;
                                wwnreadack++;
                                break;
                        case 3:         /* nack checkpoint */
                                tt.tt_ack = -1;
                                zz_lastc = -1;
                                wwnreadnack++;
                                break;
                        default:
                                zz_lastc = c;
                                wwnreadec++;
                        }
                } else if (zz_ecc == 1) {
                        if (c)
                                *q++ = c;
                        else
                                zz_lastc = 0;
                } else {
                        if (zz_lastc < 0) {
                                zz_lastc = c;
                        } else if (zz_lastc == c) {
                                *q++ = zz_lastc;
                                zz_lastc = -1;
                        } else {
                                wwnreadec++;
                                zz_lastc = c;
                        }
                }
        }
        return q - (p - n);
}

void
zz_checksum(char *p, int n)
{
        while (--n >= 0) {
                int c = *p++ & 0x7f;
                c ^= zz_sum;
                zz_sum = c << 1 | (c >> 11 & 1);
        }
}

void
zz_compress(int flag)
{
        if (flag)
                tt.tt_checksum = 0;
        else
                tt.tt_checksum = zz_checksum;
}

void
zz_checkpoint(void)
{
        static char x[] = { ctrl('['), 'V', 0, 0 };

        zz_checksum(x, sizeof x);
        ttesc('V');
        ttputc(' ' + (zz_sum & 0x3f));
        ttputc(' ' + (zz_sum >> 6 & 0x3f));
        ttflush();
        zz_sum = 0;
}

int
tt_zapple(void)
{
        tt.tt_insspace = zz_insspace;
        tt.tt_delchar = zz_delchar;
        tt.tt_insline = zz_insline;
        tt.tt_delline = zz_delline;
        tt.tt_clreol = zz_clreol;
        tt.tt_clreos = zz_clreos;
        tt.tt_scroll_down = zz_scroll_down;
        tt.tt_scroll_up = zz_scroll_up;
        tt.tt_setscroll = zz_setscroll;
        tt.tt_availmodes = WWM_REV;
        tt.tt_wrap = 1;
        tt.tt_retain = 0;
        tt.tt_ncol = NCOL;
        tt.tt_nrow = NROW;
        tt.tt_start = zz_start;
        tt.tt_reset = zz_reset;
        tt.tt_end = zz_end;
        tt.tt_write = zz_write;
        tt.tt_putc = zz_putc;
        tt.tt_move = zz_move;
        tt.tt_clear = zz_clear;
        tt.tt_setmodes = zz_setmodes;
        tt.tt_frame = gen_frame;
        tt.tt_padc = TT_PADC_NONE;
        tt.tt_ntoken = 127;
        tt.tt_set_token = zz_set_token;
        tt.tt_put_token = zz_put_token;
        tt.tt_token_min = 1;
        tt.tt_token_max = TOKEN_MAX;
        tt.tt_set_token_cost = 2;
        tt.tt_put_token_cost = 1;
        tt.tt_compress = zz_compress;
        tt.tt_checksum = zz_checksum;
        tt.tt_checkpoint = zz_checkpoint;
        tt.tt_reset = zz_reset;
        tt.tt_rint = zz_rint;
        return 0;
}