/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (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 2004 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * m_cc.c
 *
 * XCurses Library
 *
 * Copyright 1990, 1995 by Mortice Kern Systems Inc.  All rights reserved.
 *
 */

#if M_RCSID
#ifndef lint
static char rcsID[] = "$Header: /rd/src/libc/xcurses/rcs/m_cc.c 1.8 1995/09/20 15:26:52 ant Exp $";
#endif
#endif

#include <private.h>
#include <errno.h>
#include <limits.h>
#include <string.h>
#include <m_wio.h>

typedef struct {
        int max;
        int used;
        char *mbs;
} t_string;

static int
write_string(byte, sp)
int byte;
t_string *sp;
{
        if (sp->max <= sp->used)
                return EOF;

        sp->mbs[sp->used++] = byte;

        return byte;
}

/*
 * Convert a wint_t string into a multibyte string.
 *
 * The conversion stops at the end of string or the first WEOF.
 * Return the number of bytes successfully placed into mbs.
 */
int
wistombs(mbs, wis, n)
char *mbs;
const wint_t *wis;
int n;
{
        int last;
        t_string string = { 0 };
        t_wide_io convert = { 0 };

        string.max = n;
        string.mbs = mbs;
        convert.object = (void *) &string;
        convert.put = (int (*)(int, void *)) write_string;

        for (;; ++wis) {
                /* In case of error, rewind string to the last character. */
                last = string.used;

                if (m_wio_put(*wis, &convert) < 0) {
                        string.used = last;
                        break;
                }

                /* Test for end of string AFTER trying to copy into the
                 * buffer, because m_wio_put() has to handle state changes
                 * back to the initial state on '\0' or WEOF.
                 */
                if (*wis == '\0' || *wis == WEOF)
                        break;
        }

        /* m_wio_put() does not write '\0', because the "stream"
         * object is considered to be in "text" mode, which in the
         * case of file I/O produces undefined results for systems
         * using locking-shift character sets.
         */
        string.mbs[string.used] = '\0';

        return string.used;
}

/*
 * Convert a wint_t string (filled in by wgetn_wstr()) to a wchar_t string.
 * The conversion stops at the end of string or the first WEOF.  Return the
 * number of successfully copied characters.
 *
 * This routinue should be used when sizeof (wchar_t) < sizeof (wint_t).
 */
int
wistowcs(wcs, wis, n)
wchar_t *wcs;
const wint_t *wis;
int n;
{
        wchar_t *start;

        if (n < 0)
                n = INT_MAX;

        for (start = wcs; *wis != '\0' && 0 < n; ++wis, ++wcs, --n) {
                if (*wis == WEOF)
                        break;
                *wcs = (wchar_t) *wis;
        }
        *wcs = '\0';

        return (int) (wcs - start);
}

/*
 * Convert a chtype to a cchar_t.
 */
int
__m_chtype_cc(ch, cc)
chtype ch;
cchar_t *cc;
{
        char mb;

        cc->_f = 1;
        cc->_n = 1;
        mb = (char)(ch & A_CHARTEXT);

        if (mbtowc(cc->_wc, &mb, 1) < 0)
                return ERR;

        cc->_co = (short) PAIR_NUMBER(ch);
        cc->_at = (attr_t) ((ch & (A_ATTRIBUTES & ~A_COLOR)) >> 16);

        return OK;
}

/*
 * Return a complex character as a chtype.
 */
chtype
__m_cc_chtype(cc)
const cchar_t *cc;
{
        chtype ch;
        unsigned char mb[MB_LEN_MAX];

        /* Is it a single-byte character? */
        if (cc->_n != 1 || wctomb((char *) mb, cc->_wc[0]) != 1)
                return (chtype) ERR;

        ch = ((chtype) cc->_at << 16) & ~A_COLOR;
        ch |= COLOR_PAIR(cc->_co) | mb[0];

        return ch;
}

/*
 * Convert a complex character's "character" into a multibyte string.
 * The attribute and colour are ignored.
 *
 * If 0 < n, set a new multibyte string and convert the first character,
 * returning either -1 on error or the number of bytes used to convert the
 * character.
 *
 * If n == 0, continue appending to the current multibyte string and return
 * a value as for 0 < n case.
 *
 * If n < 0, return the accumulated byte length of the current multibyte
 * string and do nothing else.
 *
 * When converting a character, a null cchar_t pointer will force the initial
 * shift state and append a '\0' to the multibyte string.  The return value
 * will instead by the number of bytes used to shift to the initial state,
 * and exclude the '\0'.
 */
int
__m_cc_mbs(cc, mbs, n)
const cchar_t *cc;
char *mbs;
int n;
{
        cchar_t *cp;
        int i, bytes, count, last;
        mbstate_t initial = { 0 };
        static t_string string = { 0 };
        static t_wide_io convert = { 0 };

        if (n < 0) {
                /* Return total number of bytes written to multibyte string. */
                return string.used;
        } else if (0 < n) {
                /* Start a new conversion. */
                string.max = n;
                string.used = 0;
                string.mbs = mbs;

                convert._state = initial;
                convert._next = convert._size = 0;
                convert.object = (void *) &string;
                convert.put = (int (*)(int, void *)) write_string;
        } /* else n == 0, continue appending to previous mbs. */

        /* In case of error, rewind string to the last character. */
        last = string.used;

        if (cc == (cchar_t *) 0) {
                /* Force initial shift state. */
                if ((count = m_wio_put('\0', &convert)) < 0) {
                        string.used = last;
                        return -1;
                }

                if (string.used < string.max)
                        string.mbs[string.used++] = '\0';
        } else {
                for (count = i = 0; i < cc->_n; ++i, count += bytes)
                        if ((bytes = m_wio_put(cc->_wc[i], &convert)) < 0) {
                                string.used = last;
                                return -1;
                        }
        }

        return count;
}

/*
 * Convert a stty character into a wchar_t.
 */
int
__m_tty_wc(index, wcp)
int index;
wchar_t *wcp;
{
        char mb;
        int code;

        /* Refer to _shell instead of _prog, since _shell will
         * correctly reflect the user's prefered settings, whereas
         * _prog may not have been initialised if both input and
         * output have been redirected.
         */
        mb = cur_term->_shell.c_cc[index];
        code = mbtowc(wcp, &mb, 1) < 0 ? ERR : OK;

        return code;
}

/*
 * Build a cchar_t from the leading spacing and non-spacing characters
 * in the multibyte character string.  Only one spacing character is copied
 * from the multibyte character string.
 *
 * Return the number of characters copied from the string, or -1 on error.
 */
int
__m_mbs_cc(const char *mbs, attr_t at, short co, cchar_t *cc)
{
        wchar_t wc;
        const char *start;
        int i, nbytes, width, have_one;

        for (start = mbs, have_one = i = 0; *mbs != '\0'; mbs += nbytes, ++i) {
                if (sizeof cc->_wc <= i)
                        /* Too many characters. */
                        return -1;

                if ((nbytes = mbtowc(&wc, mbs, UINT_MAX)) < 0)
                        /* Invalid multibyte sequence. */
                        return -1;

                if (nbytes == 0)
                        /* Remainder of string evaluates to the null byte. */
                        break;

                if (iscntrl(*mbs))
                        /* Treat control codes like a spacing character. */
                        width = 1;
                else if ((width = wcwidth(wc)) < 0)
                        return -1;

                /* Do we have a spacing character? */
                if (0 < width) {
                        if (have_one)
                                break;
                        have_one = 1;
                }

                cc->_wc[i] = wc;
        }

        cc->_f = 1;
        cc->_n = i;
        cc->_co = co;
        cc->_at = at;

        (void) __m_cc_sort(cc);

        return (int) (mbs - start);
}

/*
 * Build a cchar_t from the leading spacing and non-spacing characters
 * in the wide character string.  Only one spacinig character is copied
 * from the wide character string.
 *
 * Return the number of characters copied from the string, or -1 on error.
 */
int
__m_wcs_cc(const wchar_t *wcs, attr_t at, short co, cchar_t *cc)
{
        short i;
        int width, have_one;
        const wchar_t *start;

        for (start = wcs, have_one = i = 0; *wcs != '\0'; ++wcs, ++i) {
                if (sizeof cc->_wc <= i)
                        /* Too many characters. */
                        return -1;

                if ((width = wcwidth(*wcs)) < 0)
                        return -1;

                if (0 < width) {
                        if (have_one)
                                break;
                        have_one = 1;
                }

                cc->_wc[i] = *wcs;
        }

        cc->_f = 1;
        cc->_n = i;
        cc->_co = co;
        cc->_at = at;

        (void) __m_cc_sort(cc);

        return (int) (wcs - start);
}

/*
 * Convert a single wide character into a complex character.
 */
int
__m_wc_cc(wint_t wc, cchar_t *cc)
{
        wchar_t wcs[2];

        if (wc == WEOF)
                return -1;

        wcs[0] = (wchar_t)wc;
        wcs[1] = '\0';
        (void) __m_wcs_cc(wcs, WA_NORMAL, 0, cc);

        return 0;
}

/*
 * Sort a complex character into a spacing character followed
 * by any non-spacing characters in increasing order of oridinal
 * values.  This facilitates both comparision and writting of
 * complex characters.  More than one spacing character is
 * considered an error.
 *
 * Return the spacing character's column width or -1 if more
 * than one spacing character appears in cc.
 */
int
__m_cc_sort(cc)
cchar_t *cc;
{
        wchar_t wc;
        int width, i, j, spacing;

        /* Find spacing character and place in as first element. */
        for (width = spacing = i = 0; i < cc->_n; ++i) {
                j = wcwidth(cc->_wc[i]);
                if (0 < j) {
                        /* More than one spacing character is an error. */
                        if (0 < width)
                                return -1;

                        wc = cc->_wc[0];
                        cc->_wc[0] = cc->_wc[i];
                        cc->_wc[i]  = wc;

                        spacing = 1;
                        width = j;
                        break;
                }
        }

        /* Bubble sort small array. */
        for (i = spacing; i < cc->_n; ++i) {
                for (j = cc->_n - 1; i < j; --j) {
                        if (cc->_wc[j-1] > cc->_wc[j]) {
                                wc = cc->_wc[j];
                                cc->_wc[j] = cc->_wc[j-1];
                                cc->_wc[j-1]  = wc;
                        }
                }
        }

        return width;
}

/*
 * Return width inn screen columns of the character.
 */
int
__m_cc_width(cc)
const cchar_t *cc;
{
        return wcwidth(cc->_wc[0]);
}

/*
 * Return the first column of a multi-column character, in window.
 */
int
__m_cc_first(w, y, x)
WINDOW *w;
int y, x;
{
        register cchar_t *lp;

        for (lp = w->_line[y]; 0 < x; --x) {
                if (lp[x]._f)
                        break;
        }

        return x;
}

/*
 * Return the start of the next multi-column character, in window.
 */
int
__m_cc_next(w, y, x)
WINDOW *w;
int y, x;
{
        cchar_t *lp;

        for (lp = w->_line[y]; ++x < w->_maxx; ) {
                if (lp[x]._f)
                        break;
        }

        return x;
}

/*
 * Return true if valid last column of a multi-column character.
 */
int
__m_cc_islast(w, y, x)
WINDOW *w;
int y, x;
{
        int first, width;

        first = __m_cc_first(w, y, x);
        width = __m_cc_width(&w->_line[y][x]);

        return first + width == x + 1;
}

/*
 * Replace the character at the current cursor location
 * according to the column width of the character.  The
 * cursor does not advance.
 *
 * Return -1 if the character won't fit on the line and the background
 * was written in its place; else return the width of the character in
 * screen columns.
 */
int
__m_cc_replace(w, y, x, cc, as_is)
WINDOW *w;
int y, x;
const cchar_t *cc;
int as_is;
{
        int i, width;
        cchar_t *cp, *np;

        width = __m_cc_width(cc);

        /* If we try to write a broad character that would exceed the
         * right margin, then write the background character instead.
         */
        if (0 < width && w->_maxx < x + width) {
                (void) __m_cc_erase(w, y, x, y, w->_maxx-1);
                return -1;
        }

        /* Erase the region to be occupied by the new character.
         * __m_cc_erase() will erase whole characters so that
         * writing a multicolumn character that overwrites the
         * trailing and leading portions of two already existing
         * multicolumn characters, erases the remaining portions.
         */
        (void) __m_cc_erase(w, y, x, y, x + width - 1);

        /* Write the first column of the character. */
        cp = &w->_line[y][x++];
        if (cc->_wc[0] == ' ' || cc->_wc[0] == M_MB_L(' ')) {
                *cp = w->_bg;
                cp->_at |= cc->_at;
                if (cc->_co != 0)
                        cp->_co = cc->_co;
        } else {
                (void) __m_wacs_cc(cc, cp);
                if (cc->_co == 0)
                        cp->_co = w->_fg._co;
        }

        cp->_at |= w->_fg._at | w->_bg._at;

        /* Mark this as the first column of the character. */
        cp->_f = 1;

        /* Duplicate the character in every column the character occupies. */
        for (np = cp + 1, i = 1; i < width; ++i, ++x, ++np) {
                *np = *cp;
                np->_f = 0;
        }

        return width;
}

int
__m_do_scroll(WINDOW *w, int y, int x, int *yp, int *xp)
{
        if (w->_maxx <= x)
                x = w->_maxx-1;

        ++y;

        if (y == w->_bottom) {
                --y;
                if (w->_flags & W_CAN_SCROLL) {
                        if (wscrl(w, 1) == ERR)
                                return ERR;
                        x = 0;
                }
        } else if (w->_maxy <= y) {
                y = w->_maxy-1;
        } else {
                /* The cursor wraps for any line (in and out of the scroll
                 * region) except for the last line of the scroll region.
                 */
                x = 0;
        }

        *yp = y;
        *xp = x;

        return OK;
}

/*
 * Add the character at the current cursor location
 * according to the column width of the character.
 * The cursor will be advanced.
 *
 * Return ERR if adding the character causes the
 * screen to scroll, when it is disallowed.
 */
int
__m_cc_add(w, y, x, cc, as_is, yp, xp)
WINDOW *w;
int y, x;
const cchar_t *cc;
int as_is, *yp, *xp;
{
        int nx, width, code = ERR;

#ifdef M_CURSES_TRACE
        __m_trace(
                "__m_cc_add(%p, %d, %d, %p, %d, %p, %p)",
                w, y, x, cc, as_is, yp, xp
        );
#endif

        switch (cc->_wc[0]) {
        case '\t':
                nx = x + (8 - (x & 07));
                if (__m_cc_erase(w, y, x, y, nx-1) == -1)
                        goto error;
                x = nx;

                if (w->_maxx <= x) {
                        if (__m_do_scroll(w, y, x, &y, &x) == ERR)
                                goto error;
                }
                break;
        case '\n':
                if (__m_cc_erase(w, y, x, y, w->_maxx-1) == -1)
                        goto error;

                if (__m_do_scroll(w, y, x, &y, &x) == ERR)
                        goto error;
                break;
        case '\r':
                x = 0;
                break;
        case '\b':
                if (0 < x)
                        --x;
                break;
        default:
                width = __m_cc_replace(w, y, x, cc, as_is);

                x += width;

                if (width < 0 || w->_maxx <= x) {
                        if (__m_do_scroll(w, y, x, &y, &x) == ERR)
                                goto error;

                        if (width < 0)
                                x += __m_cc_replace(w, y, x, cc, as_is);
                }
        }

        code = OK;
error:
        *yp = y;
        *xp = x;

        return __m_return_code("__m_cc_add", code);
}

/*
 * Erase region from (y,x) to (ly, lx) inclusive.  The
 * region is extended left and right in the case where
 * the portions of a multicolumn characters are erased.
 *
 * Return -1 if the region is not an integral multiple
 * of the background character, else zero for success.
 */
int
__m_cc_erase(w, y, x, ly, lx)
WINDOW *w;
int y, x, ly, lx;
{
        cchar_t *cp;
        int i, width;

        if (ly < y)
                return -1;

        if (w->_maxy <= ly)
                ly = w->_maxy - 1;
        if (w->_maxx <= lx)
                lx = w->_maxx - 1;

        /* Erase from first whole character (inclusive) to next
         * character (exclusive).
         */
        x = __m_cc_first(w, y, x);
        lx = __m_cc_next(w, ly, lx) - 1;

        /* Is the region to blank out an integral width of the
         * background character?
         */
        width = __m_cc_width(&w->_bg);

        if (y < ly && (lx + 1) % width != 0)
                return -1;
        if ((lx - x + 1) % width != 0)
                return -1;

        for (; y < ly; ++y, x = 0) {
                if (x < w->_first[y])
                        w->_first[y] = (short) x;

                for (cp = w->_line[y], i = 0; x < w->_maxx; ++x, ++i) {
                        cp[x] = w->_bg;

                        /* The start of each new character will be set true
                         * while internal columns of the character will be
                         * reset to false.
                         */
                        cp[x]._f = (short) (i % width == 0);
                }

                if (w->_last[y] < x)
                        w->_last[y] = (short) x;
        }

        if (x < w->_first[y])
                w->_first[y] = (short) x;

        for (cp = w->_line[y], i = 0; x <= lx; ++x, ++i) {
                cp[x] = w->_bg;

                /* The start of each new character will be set true
                 * while internal columns of the character will be
                 * reset to false.
                 */
                cp[x]._f = (short) (i % width == 0);
        }

        if (w->_last[y] < x)
                w->_last[y] = (short) x;

        return 0;
}

/*
 * Expand the character to the left or right of the given position.
 * Return the value returned by __m_cc_replace().
 */
int
__m_cc_expand(w, y, x, side)
WINDOW *w;
int y, x, side;
{
        cchar_t cc;
        int dx, width;

        width = __m_cc_width(&w->_line[y][x]);

        if (side < 0)
                dx = __m_cc_next(w, y, x) - width;
        else if (0 < side)
                dx = __m_cc_first(w, y, x);
        else
                return -1;

        /* __m_cc_replace() will erase the region containing
         * the character we want to expand.
         */
        cc = w->_line[y][x];

        return __m_cc_replace(w, y, dx, &cc, 0);
}

/*
 * Return true if characters are equal.
 *
 * NOTE to guarantee correct results, make sure that both
 * characters have been passed through __m_cc_sort().
 */
int
__m_cc_compare(c1, c2, exact)
const cchar_t *c1, *c2;
int exact;
{
        int i;

        if (exact && c1->_f != c2->_f)
                return 0;
        if (c1->_n != c2->_n)
                return 0;
        if ((c1->_at & ~WA_COOKIE) != (c2->_at & ~WA_COOKIE))
                return 0;
        if (c1->_co != c2->_co)
                return 0;

        for (i = 0; i < c1->_n; ++i)
                if (c1->_wc[i] != c2->_wc[i])
                        return 0;

        return 1;
}

/*
 * Write to the stream the character portion of a cchar_t.
 */
int
__m_cc_write(cc)
const cchar_t *cc;
{
        size_t i, j;
        char mb[MB_LEN_MAX];

        errno = 0;
        for (i = 0; i < cc->_n; ++i) {
                j = wcrtomb(mb, cc->_wc[i], &__m_screen->_state);
                if (errno != 0)
                        return EOF;
                if (fwrite(mb, sizeof *mb, j, __m_screen->_of) == 0)
                        return EOF;
        }

        return 0;
}