/* $Id$ */
#include "bbs.h"

#define o_clear()     output(clearbuf,clearbuflen)
#define o_cleol()     output(cleolbuf,cleolbuflen)
#define o_scrollrev() output(scrollrev,scrollrevlen)
#define o_standup()   output(strtstandout,strtstandoutlen)
#define o_standdown() output(endstandout,endstandoutlen)

static unsigned char cur_ln = 0, cur_col = 0;
static unsigned char docls, downfrom = 0;
static unsigned char standing = NA;
static int      scrollcnt, tc_col, tc_line;

#define MODIFIED (1)        /* if line has been modifed, screen output */
#define STANDOUT (2)        /* if this line has a standout region */


void
initscr()
{
    if (!big_picture) {
    big_picture = (screenline_t *) calloc(scr_lns, sizeof(screenline_t));
    docls = YEA;
    }
}

void
move(int y, int x)
{
    cur_col = x;
    cur_ln = y;
}

void
getyx(int *y, int *x)
{
    *y = cur_ln;
    *x = cur_col;
}

static void
rel_move(int was_col, int was_ln, int new_col, int new_ln)
{
    if (new_ln >= t_lines || new_col >= t_columns)
    return;

    tc_col = new_col;
    tc_line = new_ln;
    if (new_col == 0) {
    if (new_ln == was_ln) {
        if (was_col)
        ochar('\r');
        return;
    } else if (new_ln == was_ln + 1) {
        ochar('\n');
        if (was_col)
        ochar('\r');
        return;
    }
    }
    if (new_ln == was_ln) {
    if (was_col == new_col)
        return;

    if (new_col == was_col - 1) {
        ochar(Ctrl('H'));
        return;
    }
    }
    do_move(new_col, new_ln);
}

static void
standoutput(char *buf, int ds, int de, int sso, int eso)
{
    int             st_start, st_end;

    if (eso <= ds || sso >= de) {
    output(buf + ds, de - ds);
    } else {
    st_start = MAX(sso, ds);
    st_end = MIN(eso, de);
    if (sso > ds)
        output(buf + ds, sso - ds);
    o_standup();
    output(buf + st_start, st_end - st_start);
    o_standdown();
    if (de > eso)
        output(buf + eso, de - eso);
    }
}

void
redoscr()
{
    register screenline_t *bp;
    register int    i, j, len;

    o_clear();
    for (tc_col = tc_line = i = 0, j = roll; i < scr_lns; i++, j++) {
    if (j >= scr_lns)
        j = 0;
    bp = &big_picture[j];
    if ((len = bp->len)) {
        rel_move(tc_col, tc_line, 0, i);
        if (bp->mode & STANDOUT) {
        standoutput((char *)bp->data, 0, len, bp->sso, bp->eso);
        }
        else
        output((char *)bp->data, len);
        tc_col += len;
        if (tc_col >= t_columns) {
        /* XXX Is this code right? */
        if (automargins)
            tc_col = t_columns - 1;
        else {
            tc_col -= t_columns;
            tc_line++;
            if (tc_line >= t_lines)
            tc_line = b_lines;
        }
        }
        bp->mode &= ~(MODIFIED);
        bp->oldlen = len;
    }
    }
    rel_move(tc_col, tc_line, cur_col, cur_ln);
    docls = scrollcnt = 0;
    oflush();
}

void
refresh()
{
    /* TODO remove unnecessary refresh() call, to save CPU time */
    register screenline_t *bp = big_picture;
    register int    i, j, len;
    if (num_in_buf())
    return;

    if ((docls) || (abs(scrollcnt) >= (scr_lns - 3))) {
    redoscr();
    return;
    }
    if (scrollcnt < 0) {
    if (!scrollrevlen) {
        redoscr();
        return;
    }
    rel_move(tc_col, tc_line, 0, 0);
    do {
        o_scrollrev();
    } while (++scrollcnt);
    } else if (scrollcnt > 0) {
    rel_move(tc_col, tc_line, 0, b_lines);
    do {
        ochar('\n');
    } while (--scrollcnt);
    }
    for (i = 0, j = roll; i < scr_lns; i++, j++) {
    if (j >= scr_lns)
        j = 0;
    bp = &big_picture[j];
    len = bp->len;
    if (bp->mode & MODIFIED && bp->smod < len) {
        bp->mode &= ~(MODIFIED);
        if (bp->emod >= len)
        bp->emod = len - 1;
        rel_move(tc_col, tc_line, bp->smod, i);

        if (bp->mode & STANDOUT)
        standoutput((char *)bp->data, bp->smod, bp->emod + 1,
                bp->sso, bp->eso);
        else
        output((char *)&bp->data[bp->smod], bp->emod - bp->smod + 1);
        tc_col = bp->emod + 1;
        if (tc_col >= t_columns) {
        /* XXX Is this code right? */
        if (automargins)
            tc_col = t_columns - 1;
        else {
            tc_col -= t_columns;
            tc_line++;
            if (tc_line >= t_lines)
            tc_line = b_lines;
        }
        }
    }
    if (bp->oldlen > len) {
        /* XXX len/oldlen also count the length of escape sequence,
         * before we fix it, we must print \033[K everywhere */
        rel_move(tc_col, tc_line, len, i);
        o_cleol();
    }
    bp->oldlen = len;

    }

    rel_move(tc_col, tc_line, cur_col, cur_ln);

    oflush();
}

void
clear()
{
    register screenline_t *slp;

    register int    i;

    docls = YEA;
    cur_col = cur_ln = roll = downfrom = 0;
    for(i=0; i<scr_lns; i++) {
    slp = &big_picture[i];
    slp->mode = slp->len = slp->oldlen = 0;
    }
}

void
clrtoeol()
{
    register screenline_t *slp;
    register int    ln;

    standing = NA;
    if ((ln = cur_ln + roll) >= scr_lns)
    ln -= scr_lns;
    slp = &big_picture[ln];
    if (cur_col <= slp->sso)
    slp->mode &= ~STANDOUT;

    if (cur_col > slp->oldlen) {
    for (ln = slp->len; ln <= cur_col; ln++)
        slp->data[ln] = ' ';
    }
    if (cur_col < slp->oldlen) {
    for (ln = slp->len; ln >= cur_col; ln--)
        slp->data[ln] = ' ';
    }
    slp->len = cur_col;
}

/**
 * 從目前的行數(scr_ln) clear 到第 line 行
 */
void
clrtoline(int line)
{
    register screenline_t *slp;
    register int    i, j;

    for (i = cur_ln, j = i + roll; i < line; i++, j++) {
    if (j >= scr_lns)
        j -= scr_lns;
    slp = &big_picture[j];
    slp->mode = slp->len = 0;
    if (slp->oldlen)
        slp->oldlen = 255;
    }
}

/**
 * 從目前的行數(scr_ln) clear 到底
 */
inline void
clrtobot()
{
    clrtoline(scr_lns);
}

void
outc(unsigned char c)
{
    register screenline_t *slp;
    register int    i;

    if ((i = cur_ln + roll) >= scr_lns)
    i -= scr_lns;
    slp = &big_picture[i];

    if (c == '\n' || c == '\r') {
    if (standing) {
        slp->eso = MAX(slp->eso, cur_col);
        standing = NA;
    }
    if ((i = cur_col - slp->len) > 0)
        memset(&slp->data[slp->len], ' ', i + 1);
    slp->len = cur_col;
    cur_col = 0;
    if (cur_ln < scr_lns)
        cur_ln++;
    return;
    }
    /*
     * else if(c != '\033' && !isprint2(c)) { c = '*'; //substitute a '*' for
     * non-printable }
     */
    if (cur_col >= slp->len) {
    for (i = slp->len; i < cur_col; i++)
        slp->data[i] = ' ';
    slp->data[cur_col] = '\0';
    slp->len = cur_col + 1;
    }
    if (slp->data[cur_col] != c) {
    slp->data[cur_col] = c;
    if (!(slp->mode & MODIFIED))
        slp->smod = slp->emod = cur_col;
    slp->mode |= MODIFIED;
    if (cur_col > slp->emod)
        slp->emod = cur_col;
    if (cur_col < slp->smod)
        slp->smod = cur_col;
    }
#if 1
    ++cur_col;
#else
    /* this comparison is always false (cur_col is unsigned char and scr_cols
     * is 511). */
    if (++cur_col >= scr_cols) {
    if (standing && (slp->mode & STANDOUT)) {
        standing = 0;
        slp->eso = MAX(slp->eso, cur_col);
    }
    cur_col = 0;
    if (cur_ln < scr_lns)
        cur_ln++;
    }
#endif
}

int
edit_outs(const char *text)
{
    register int    column = 0;
    register char   ch;
    while ((ch = *text++) && (++column < t_columns))
    outc(ch == 27 ? '*' : ch);

    return 0;
}

void
outs(const char *str)
{
    while (*str) {
    outc(*str++);
    }
}

/* Jaky */
void
out_lines(const char *str, int line)
{
    while (*str && line) {
    outc(*str);
    if (*str == '\n')
        line--;
    str++;
    }
}

void
outmsg(char *msg)
{
    move(b_lines, 0);
    clrtoeol();
    outs(msg);
}

void
prints(const char *fmt,...)
{
    va_list         args;
    char            buff[1024];

    va_start(args, fmt);
    vsnprintf(buff, sizeof(buff), fmt, args);
    va_end(args);
    outs(buff);
}

void
mouts(int y, int x, char *str)
{
    move(y, x);
    clrtoeol();
    outs(str);
}

void
scroll()
{
    scrollcnt++;
    if (++roll >= scr_lns)
    roll = 0;
    move(b_lines, 0);
    clrtoeol();
}

void
rscroll()
{
    scrollcnt--;
    if (--roll < 0)
    roll = b_lines;
    move(0, 0);
    clrtoeol();
}

void
region_scroll_up(int top, int bottom)
{
    int             i;

    if (top > bottom) {
    i = top;
    top = bottom;
    bottom = i;
    }
    if (top < 0 || bottom >= scr_lns)
    return;

    for (i = top; i < bottom; i++)
    big_picture[i] = big_picture[i + 1];
    memset(big_picture + i, 0, sizeof(*big_picture));
    memset(big_picture[i].data, ' ', scr_cols);
    save_cursor();
    change_scroll_range(top, bottom);
    do_move(0, bottom);
    scroll_forward();
    change_scroll_range(0, scr_lns - 1);
    restore_cursor();
    refresh();
}

void
standout()
{
    if (!standing && strtstandoutlen) {
    register screenline_t *slp;

    slp = &big_picture[((cur_ln + roll) % scr_lns)];
    standing = YEA;
    slp->sso = slp->eso = cur_col;
    slp->mode |= STANDOUT;
    }
}

void
standend()
{
    if (standing && strtstandoutlen) {
    register screenline_t *slp;

    slp = &big_picture[((cur_ln + roll) % scr_lns)];
    standing = NA;
    slp->eso = MAX(slp->eso, cur_col);
    }
}

void screen_backup(int len, screenline_t *bp, void *buf)
{
    int i;
    size_t offset=0;
    for(i=0;i<len;i++) {
    memcpy((char*)buf+offset, &bp[i], ((char*)&bp[i].data-(char*)&bp[i]));
    offset+=((char*)&bp[i].data-(char*)&bp[i]);
    memcpy((char*)buf+offset, &bp[i].data, bp[i].len);
    offset+=bp[i].len;
    }
}

size_t screen_backupsize(int len, screenline_t *bp)
{
    int i;
    size_t sum=0;
    for(i=0;i<len;i++)
    sum+=((char*)&bp[i].data-(char*)&bp[i]) + bp[i].len;
    return sum;
}

void screen_restore(int len, screenline_t *bp, void *buf)
{
    int i;
    size_t offset=0;
    for(i=0;i<len;i++) {
    memcpy(&bp[i], (char*)buf+offset, ((char*)&bp[i].data-(char*)&bp[i]));
    offset+=((char*)&bp[i].data-(char*)&bp[i]);
    memcpy(&bp[i].data, (char*)buf+offset, bp[i].len);
    offset+=bp[i].len;
    }
}