/* $OpenBSD: wsemul_dumb.c,v 1.14 2020/05/25 09:55:49 jsg Exp $ */
/* $NetBSD: wsemul_dumb.c,v 1.7 2000/01/05 11:19:36 drochner Exp $ */

/*
 * Copyright (c) 1996, 1997 Christopher G. Demetriou.  All rights reserved.
 *
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by Christopher G. Demetriou
 *      for the NetBSD Project.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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 <sys/param.h>
#include <sys/systm.h>
#include <sys/time.h>
#include <sys/malloc.h>
#include <sys/fcntl.h>

#include <dev/wscons/wsconsio.h>
#include <dev/wscons/wsdisplayvar.h>
#include <dev/wscons/wsemulvar.h>
#include <dev/wscons/ascii.h>

void    *wsemul_dumb_cnattach(const struct wsscreen_descr *, void *,
                                   int, int, uint32_t);
void    *wsemul_dumb_attach(int, const struct wsscreen_descr *,
                                 void *, int, int, void *, uint32_t);
u_int   wsemul_dumb_output(void *, const u_char *, u_int, int);
int     wsemul_dumb_translate(void *, kbd_t, keysym_t, const u_char **);
void    wsemul_dumb_detach(void *, u_int *, u_int *);
void    wsemul_dumb_resetop(void *, enum wsemul_resetops);

const struct wsemul_ops wsemul_dumb_ops = {
        "dumb",
        wsemul_dumb_cnattach,
        wsemul_dumb_attach,
        wsemul_dumb_output,
        wsemul_dumb_translate,
        wsemul_dumb_detach,
        wsemul_dumb_resetop
};

struct wsemul_dumb_emuldata {
        const struct wsdisplay_emulops *emulops;
        struct wsemul_abortstate abortstate;
        void *emulcookie;
        void *cbcookie;
        int crippled;
        u_int nrows, ncols, crow, ccol;
        uint32_t defattr;
};

struct wsemul_dumb_emuldata wsemul_dumb_console_emuldata;

void *
wsemul_dumb_cnattach(const struct wsscreen_descr *type, void *cookie, int ccol,
    int crow, uint32_t defattr)
{
        struct wsemul_dumb_emuldata *edp;
        const struct wsdisplay_emulops *emulops;

        edp = &wsemul_dumb_console_emuldata;

        edp->emulops = emulops = type->textops;
        edp->emulcookie = cookie;
        edp->nrows = type->nrows;
        edp->ncols = type->ncols;
        edp->crow = crow;
        edp->ccol = ccol;
        edp->defattr = defattr;
        edp->cbcookie = NULL;
        edp->crippled = emulops->cursor == NULL ||
            emulops->copycols == NULL || emulops->copyrows == NULL ||
            emulops->erasecols == NULL || emulops->eraserows == NULL;
        wsemul_reset_abortstate(&edp->abortstate);

        return (edp);
}

void *
wsemul_dumb_attach(int console, const struct wsscreen_descr *type, void *cookie,
    int ccol, int crow, void *cbcookie, uint32_t defattr)
{
        struct wsemul_dumb_emuldata *edp;

        if (console)
                edp = &wsemul_dumb_console_emuldata;
        else {
                edp = malloc(sizeof *edp, M_DEVBUF, M_WAITOK);

                edp->emulops = type->textops;
                edp->emulcookie = cookie;
                edp->nrows = type->nrows;
                edp->ncols = type->ncols;
                edp->crow = crow;
                edp->ccol = ccol;
                edp->defattr = defattr;
                wsemul_reset_abortstate(&edp->abortstate);
        }

        edp->cbcookie = cbcookie;

        return (edp);
}

u_int
wsemul_dumb_output(void *cookie, const u_char *data, u_int count, int kernel)
{
        struct wsemul_dumb_emuldata *edp = cookie;
        u_int processed = 0;
        u_char c;
        int n;
        int rc = 0;

        if (edp->crippled) {
                while (count-- > 0) {
                        wsemul_resume_abort(&edp->abortstate);

                        c = *data++;
                        if (c == ASCII_BEL)
                                wsdisplay_emulbell(edp->cbcookie);
                        else {
                                WSEMULOP(rc, edp, &edp->abortstate, putchar,
                                    (edp->emulcookie, 0, 0, c, 0));
                                if (rc != 0)
                                        break;
                        }
                        processed++;
                }
                if (rc != 0)
                        wsemul_abort_other(&edp->abortstate);
                return processed;
        }

        switch (edp->abortstate.state) {
        case ABORT_FAILED_CURSOR:
                /*
                 * If we could not display the cursor back, we pretended not
                 * having been able to display the last character. But this
                 * is a lie, so compensate here.
                 */
                data++, count--;
                processed++;
                wsemul_reset_abortstate(&edp->abortstate);
                break;
        case ABORT_OK:
                /* remove cursor image */
                rc = (*edp->emulops->cursor)
                    (edp->emulcookie, 0, edp->crow, edp->ccol);
                if (rc != 0)
                        return 0;
                break;
        default:
                break;
        }

        while (count-- > 0) {
                wsemul_resume_abort(&edp->abortstate);

                c = *data++;
                switch (c) {
                case ASCII_BEL:
                        wsdisplay_emulbell(edp->cbcookie);
                        break;

                case ASCII_BS:
                        if (edp->ccol > 0)
                                edp->ccol--;
                        break;

                case ASCII_CR:
                        edp->ccol = 0;
                        break;

                case ASCII_HT:
                        n = min(8 - (edp->ccol & 7),
                            edp->ncols - edp->ccol - 1);
                        WSEMULOP(rc, edp, &edp->abortstate, erasecols,
                             (edp->emulcookie, edp->crow, edp->ccol, n,
                              edp->defattr));
                        if (rc != 0)
                                break;
                        edp->ccol += n;
                        break;

                case ASCII_FF:
                        WSEMULOP(rc, edp, &edp->abortstate, eraserows,
                            (edp->emulcookie, 0, edp->nrows, edp->defattr));
                        if (rc != 0)
                                break;
                        edp->ccol = 0;
                        edp->crow = 0;
                        break;

                case ASCII_VT:
                        if (edp->crow > 0)
                                edp->crow--;
                        break;

                default:
                        WSEMULOP(rc, edp, &edp->abortstate, putchar,
                            (edp->emulcookie, edp->crow, edp->ccol, c,
                             edp->defattr));
                        if (rc != 0)
                                break;
                        edp->ccol++;

                        /* if cur col is still on cur line, done. */
                        if (edp->ccol < edp->ncols)
                                break;

                        /* wrap the column around. */
                        edp->ccol = 0;

                        /* FALLTHROUGH */

                case ASCII_LF:
                        /* if the cur line isn't the last, incr and leave. */
                        if (edp->crow < edp->nrows - 1) {
                                edp->crow++;
                                break;
                        }
                        n = 1;          /* number of lines to scroll */
                        WSEMULOP(rc, edp, &edp->abortstate, copyrows,
                            (edp->emulcookie, n, 0, edp->nrows - n));
                        if (rc == 0)
                                WSEMULOP(rc, edp, &edp->abortstate, eraserows,
                                    (edp->emulcookie, edp->nrows - n, n,
                                     edp->defattr));
                        if (rc != 0) {
                                /* undo wrap-at-eol processing if necessary */
                                if (c != ASCII_LF)
                                        edp->ccol = edp->ncols - 1;
                                break;
                        }
                        edp->crow -= n - 1;
                        break;
                }
                if (rc != 0)
                        break;
                processed++;
        }

        if (rc != 0)
                wsemul_abort_other(&edp->abortstate);
        else {
                /* put cursor image back */
                rc = (*edp->emulops->cursor)
                    (edp->emulcookie, 1, edp->crow, edp->ccol);
                if (rc != 0) {
                        /*
                         * Fail the last character output, remembering that
                         * only the cursor operation really needs to be done.
                         */
                        wsemul_abort_cursor(&edp->abortstate);
                        processed--;
                }
        }

        if (rc == 0)
                wsemul_reset_abortstate(&edp->abortstate);

        return processed;
}

int
wsemul_dumb_translate(void *cookie, kbd_t layout, keysym_t in,
    const u_char **out)
{
        return (0);
}

void
wsemul_dumb_detach(void *cookie, u_int *crowp, u_int *ccolp)
{
        struct wsemul_dumb_emuldata *edp = cookie;

        *crowp = edp->crow;
        *ccolp = edp->ccol;
        if (edp != &wsemul_dumb_console_emuldata)
                free(edp, M_DEVBUF, sizeof *edp);
}

void
wsemul_dumb_resetop(void *cookie, enum wsemul_resetops op)
{
        struct wsemul_dumb_emuldata *edp = cookie;

        if (edp->crippled)
                return;

        switch (op) {
        case WSEMUL_CLEARSCREEN:
                (*edp->emulops->eraserows)(edp->emulcookie, 0, edp->nrows,
                                           edp->defattr);
                edp->ccol = edp->crow = 0;
                (*edp->emulops->cursor)(edp->emulcookie, 1, 0, 0);
                break;
        case WSEMUL_CLEARCURSOR:
                (*edp->emulops->cursor)(edp->emulcookie, 0,
                    edp->crow, edp->ccol);
                break;
        default:
                break;
        }
}