/* word buffer */
#include <ctype.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "roff.h"

/* the current font, size and color */
#define R_F(wb)		((wb)->r_f >= 0 ? (wb)->r_f : n_f)	/* current font */
#define R_S(wb)		((wb)->r_s >= 0 ? (wb)->r_s : n_s)	/* current size */
#define R_M(wb)		((wb)->r_m >= 0 ? (wb)->r_m : n_m)	/* current color */
/* italic correction */
#define glyph_ic(g)	(MAX(0, (g)->urx - (g)->wid))
#define glyph_icleft(g)	(MAX(0, -(g)->llx))
/* the maximum and minimum values of bounding box coordinates */
#define BBMAX		(1 << 29)
#define BBMIN		-BBMAX

static void wb_flushsub(struct wb *wb);

void wb_init(struct wb *wb)
{
	memset(wb, 0, sizeof(*wb));
	sbuf_init(&wb->sbuf);
	wb->sub_collect = 1;
	wb->f = -1;
	wb->s = -1;
	wb->m = -1;
	wb->r_f = -1;
	wb->r_s = -1;
	wb->r_m = -1;
	wb->llx = BBMAX;
	wb->lly = BBMAX;
	wb->urx = BBMIN;
	wb->ury = BBMIN;
}

void wb_done(struct wb *wb)
{
	sbuf_done(&wb->sbuf);
}

/* update wb->st and wb->sb */
static void wb_stsb(struct wb *wb)
{
	wb->st = MIN(wb->st, wb->v - (wb->s * SC_IN / 72));
	wb->sb = MAX(wb->sb, wb->v);
}

/* update bounding box */
static void wb_bbox(struct wb *wb, int llx, int lly, int urx, int ury)
{
	wb->llx = MIN(wb->llx, wb->h + llx);
	wb->lly = MIN(wb->lly, -wb->v + lly);
	wb->urx = MAX(wb->urx, wb->h + urx);
	wb->ury = MAX(wb->ury, -wb->v + ury);
}

/* pending font, size or color changes */
static int wb_pendingfont(struct wb *wb)
{
	return wb->f != R_F(wb) || wb->s != R_S(wb) ||
			(!n_cp && wb->m != R_M(wb));
}

/* append font and size to the buffer if needed */
static void wb_flushfont(struct wb *wb)
{
	if (wb->f != R_F(wb)) {
		sbuf_printf(&wb->sbuf, "%cf(%02d", c_ec, R_F(wb));
		wb->f = R_F(wb);
	}
	if (wb->s != R_S(wb)) {
		sbuf_printf(&wb->sbuf, "%cs(%02d", c_ec, R_S(wb));
		wb->s = R_S(wb);
	}
	if (!n_cp && wb->m != R_M(wb)) {
		sbuf_printf(&wb->sbuf, "%cm[%s]", c_ec, clr_str(R_M(wb)));
		wb->m = R_M(wb);
	}
	wb_stsb(wb);
}

/* apply font and size changes and flush the collected subword */
static void wb_flush(struct wb *wb)
{
	wb_flushsub(wb);
	wb_flushfont(wb);
}

void wb_hmov(struct wb *wb, int n)
{
	wb_flushsub(wb);
	wb->h += n;
	sbuf_printf(&wb->sbuf, "%ch'%du'", c_ec, n);
}

void wb_vmov(struct wb *wb, int n)
{
	wb_flushsub(wb);
	wb->v += n;
	sbuf_printf(&wb->sbuf, "%cv'%du'", c_ec, n);
}

void wb_els(struct wb *wb, int els)
{
	wb_flushsub(wb);
	if (els > wb->els_pos)
		wb->els_pos = els;
	if (els < wb->els_neg)
		wb->els_neg = els;
	sbuf_printf(&wb->sbuf, "%cx'%du'", c_ec, els);
}

void wb_etc(struct wb *wb, char *x)
{
	wb_flush(wb);
	sbuf_printf(&wb->sbuf, "%cX%s", c_ec, x);
}

static void wb_putbuf(struct wb *wb, char *c)
{
	struct glyph *g;
	int zerowidth;
	if (c[0] == '\t' || c[0] == '
' ||
			(c[0] == c_ni && (c[1] == '\t' || c[1] == '
'))) {
		sbuf_append(&wb->sbuf, c);
		return;
	}
	g = dev_glyph(c, wb->f);
	zerowidth = !strcmp(c_hc, c) || !strcmp(c_bp, c);
	if (!g && c[0] == c_ec && !zerowidth) {	/* unknown escape */
		memmove(c, c + 1, strlen(c));
		g = dev_glyph(c, wb->f);
	}
	if (g && !zerowidth && wb->icleft && glyph_icleft(g))
		wb_hmov(wb, font_wid(g->font, wb->s, glyph_icleft(g)));
	wb->icleft = 0;
	if (!c[1] || c[0] == c_ec || c[0] == c_ni || utf8one(c)) {
		if (c[0] == c_ni && c[1] == c_ec)
			sbuf_printf(&wb->sbuf, "%c%c", c_ec, c_ec);
		else
			sbuf_append(&wb->sbuf, c);
	} else {
		if (c[1] && !c[2])
			sbuf_printf(&wb->sbuf, "%c(%s", c_ec, c);
		else
			sbuf_printf(&wb->sbuf, "%cC'%s'", c_ec, c);
	}
	if (!zerowidth) {
		if (!n_cp && g)
			wb_bbox(wb, font_wid(g->font, wb->s, g->llx),
				font_wid(g->font, wb->s, g->lly),
				font_wid(g->font, wb->s, g->urx),
				font_wid(g->font, wb->s, g->ury));
		wb->h += g ? font_gwid(g->font, dev_font(wb->f), wb->s, g->wid) : 0;
		wb->ct |= g ? g->type : 0;
		wb_stsb(wb);
	}
}

int c_isdash(char *c)
{
	return !strcmp("-", c) || !strcmp("em", c) || !strcmp("hy", c);
}

/* return nonzero if it cannot be hyphenated */
static int wb_hyph(char src[][GNLEN], int src_n, char *src_hyph, int flg)
{
	char word[WORDLEN * GNLEN];	/* word to pass to hyphenate() */
	char hyph[WORDLEN * GNLEN];	/* hyphenation points of word */
	int smap[WORDLEN];		/* the mapping from src[] to word[] */
	char *s, *d;
	int i;
	d = word;
	*d = '\0';
	for (i = 0; i < src_n; i++) {
		s = src[i];
		smap[i] = d - word;
		if (c_isdash(s) || !strcmp(c_hc, s))
			return 1;
		if (!strcmp(c_bp, s))
			continue;
		if (!utf8one(s) || (!s[1] && !isalpha((unsigned char) s[0])))
			strcpy(d, ".");
		else
			strcpy(d, s);
		d = strchr(d, '\0');
	}
	memset(hyph, 0, (d - word) * sizeof(hyph[0]));
	hyphenate(hyph, word, flg);
	for (i = 0; i < src_n; i++)
		src_hyph[i] = hyph[smap[i]];
	return 0;
}

static int wb_collect(struct wb *wb, int val)
{
	int old = wb->sub_collect;
	wb->sub_collect = val;
	return old;
}

static void wb_flushsub(struct wb *wb)
{
	struct font *fn;
	struct glyph *gsrc[WORDLEN];
	struct glyph *gdst[WORDLEN];
	int x[WORDLEN], y[WORDLEN], xadv[WORDLEN], yadv[WORDLEN];
	int dmap[WORDLEN];
	char src_hyph[WORDLEN];
	int dst_n, i;
	if (!wb->sub_n || !wb->sub_collect)
		return;
	wb->sub_collect = 0;
	fn = dev_font(wb->f);
	if (!n_hy || wb_hyph(wb->sub_c, wb->sub_n, src_hyph, n_hy))
		memset(src_hyph, 0, sizeof(src_hyph));
	for (i = 0; i < wb->sub_n; i++)
		gsrc[i] = font_find(fn, wb->sub_c[i]);
	dst_n = font_layout(fn, gsrc, wb->sub_n, wb->s,
			gdst, dmap, x, y, xadv, yadv, n_lg, n_kn);
	for (i = 0; i < dst_n; i++) {
		if (x[i])
			wb_hmov(wb, font_wid(fn, wb->s, x[i]));
		if (y[i])
			wb_vmov(wb, font_wid(fn, wb->s, y[i]));
		if (src_hyph[dmap[i]])
			wb_putbuf(wb, c_hc);
		if (gdst[i] == gsrc[dmap[i]])
			wb_putbuf(wb, wb->sub_c[dmap[i]]);
		else
			wb_putbuf(wb, gdst[i]->name);
		if (x[i] || xadv[i])
			wb_hmov(wb, font_wid(fn, wb->s, xadv[i] - x[i]));
		if (y[i] || yadv[i])
			wb_vmov(wb, font_wid(fn, wb->s, yadv[i] - y[i]));
	}
	wb->sub_n = 0;
	wb->icleft = 0;
	wb->sub_collect = 1;
}

void wb_put(struct wb *wb, char *c)
{
	if (c[0] == '\n') {
		wb->part = 0;
		return;
	}
	if (c[0] == ' ') {
		wb_flushsub(wb);
		wb_hmov(wb, font_swid(dev_font(R_F(wb)), R_S(wb), n_ss));
		return;
	}
	if (wb_pendingfont(wb) || wb->sub_n == LEN(wb->sub_c))
		wb_flush(wb);
	if (wb->sub_collect) {
		if (font_find(dev_font(wb->f), c))
			strcpy(wb->sub_c[wb->sub_n++], c);
		else
			wb_putraw(wb, c);
	} else {
		wb_putbuf(wb, c);
	}
}

/* just like wb_put() but disable subword collection */
void wb_putraw(struct wb *wb, char *c)
{
	int collect;
	wb_flushsub(wb);
	collect = wb_collect(wb, 0);
	wb_put(wb, c);
	wb_collect(wb, collect);
}

/* just like wb_put(), but call cdef_expand() if c is defined */
void wb_putexpand(struct wb *wb, char *c)
{
	if (cdef_expand(wb, c, R_F(wb)))
		wb_put(wb, c);
}

int wb_part(struct wb *wb)
{
	return wb->part;
}

void wb_setpart(struct wb *wb)
{
	wb->part = 1;
}

void wb_drawl(struct wb *wb, int c, int h, int v)
{
	wb_flush(wb);
	sbuf_printf(&wb->sbuf, "%cD'%c %du %du'", c_ec, c, h, v);
	wb->h += h;
	wb->v += v;
	wb_stsb(wb);
}

void wb_drawc(struct wb *wb, int c, int r)
{
	wb_flush(wb);
	sbuf_printf(&wb->sbuf, "%cD'%c %du'", c_ec, c, r);
	wb->h += r;
}

void wb_drawe(struct wb *wb, int c, int h, int v)
{
	wb_flush(wb);
	sbuf_printf(&wb->sbuf, "%cD'%c %du %du'", c_ec, c, h, v);
	wb->h += h;
}

void wb_drawa(struct wb *wb, int c, int h1, int v1, int h2, int v2)
{
	wb_flush(wb);
	sbuf_printf(&wb->sbuf, "%cD'%c %du %du %du %du'",
			c_ec, c, h1, v1, h2, v2);
	wb->h += h1 + h2;
	wb->v += v1 + v2;
	wb_stsb(wb);
}

void wb_drawxbeg(struct wb *wb, int c)
{
	wb_flush(wb);
	sbuf_printf(&wb->sbuf, "%cD'%c", c_ec, c);
}

void wb_drawxdot(struct wb *wb, int h, int v)
{
	sbuf_printf(&wb->sbuf, " %du %du", h, v);
	wb->h += h;
	wb->v += v;
	wb_stsb(wb);
}

void wb_drawxend(struct wb *wb)
{
	sbuf_printf(&wb->sbuf, "'");
}

void wb_reset(struct wb *wb)
{
	wb_done(wb);
	wb_init(wb);
}

char *wb_buf(struct wb *wb)
{
	wb_flushsub(wb);
	return sbuf_buf(&wb->sbuf);
}

static void wb_putc(struct wb *wb, int t, char *s)
{
	if (t && t != 'C')
		wb_flushsub(wb);
	switch (t) {
	case 0:
	case 'C':
		wb_put(wb, s);
		break;
	case 'D':
		ren_dcmd(wb, s);
		break;
	case 'f':
		wb->r_f = atoi(s);
		break;
	case 'h':
		wb_hmov(wb, atoi(s));
		break;
	case 'm':
		wb->r_m = clr_get(s);
		break;
	case 's':
		wb->r_s = atoi(s);
		break;
	case 'v':
		wb_vmov(wb, atoi(s));
		break;
	case 'x':
		wb_els(wb, atoi(s));
		break;
	case 'X':
		wb_etc(wb, s);
		break;
	}
}

void wb_cat(struct wb *wb, struct wb *src)
{
	char *s;
	char d[ILNLEN];
	int c, part;
	int collect;
	wb_flushsub(src);
	wb_flushsub(wb);
	collect = wb_collect(wb, 0);
	s = sbuf_buf(&src->sbuf);
	while ((c = escread(&s, d)) >= 0)
		wb_putc(wb, c, d);
	part = src->part;
	wb->r_s = -1;
	wb->r_f = -1;
	wb->r_m = -1;
	wb_reset(src);
	src->part = part;
	wb_collect(wb, collect);
}

int wb_wid(struct wb *wb)
{
	wb_flushsub(wb);
	return wb->h;
}

int wb_hpos(struct wb *wb)
{
	wb_flushsub(wb);
	return wb->h;
}

int wb_vpos(struct wb *wb)
{
	wb_flushsub(wb);
	return wb->v;
}

int wb_empty(struct wb *wb)
{
	return !wb->sub_n && sbuf_empty(&wb->sbuf);
}

/* return 1 if wb ends a sentence (.?!) */
int wb_eos(struct wb *wb)
{
	int i = wb->sub_n - 1;
	while (i > 0 && strchr("'\")]*", wb->sub_c[i][0]))
		i--;
	return i >= 0 && strchr(".?!", wb->sub_c[i][0]);
}

void wb_wconf(struct wb *wb, int *ct, int *st, int *sb,
		int *llx, int *lly, int *urx, int *ury)
{
	wb_flushsub(wb);
	*ct = wb->ct;
	*st = -wb->st;
	*sb = -wb->sb;
	*llx = wb->llx < BBMAX ? wb->llx : 0;
	*lly = wb->lly < BBMAX ? -wb->lly : 0;
	*urx = wb->urx > BBMIN ? wb->urx : 0;
	*ury = wb->ury > BBMIN ? -wb->ury : 0;
}

static struct glyph *wb_prevglyph(struct wb *wb)
{
	return wb->sub_n ? dev_glyph(wb->sub_c[wb->sub_n - 1], wb->f) : NULL;
}

void wb_italiccorrection(struct wb *wb)
{
	struct glyph *g = wb_prevglyph(wb);
	if (g && glyph_ic(g))
		wb_hmov(wb, font_wid(g->font, wb->s, glyph_ic(g)));
}

void wb_italiccorrectionleft(struct wb *wb)
{
	wb_flushsub(wb);
	wb->icleft = 1;
}

void wb_fnszget(struct wb *wb, int *fn, int *sz, int *m)
{
	wb_flushsub(wb);
	*fn = wb->r_f;
	*sz = wb->r_s;
	*m = wb->r_m;
}

void wb_fnszset(struct wb *wb, int fn, int sz, int m)
{
	wb->r_f = fn;
	wb->r_s = sz;
	wb->r_m = m;
}

void wb_catstr(struct wb *wb, char *s, char *end)
{
	char d[ILNLEN];
	int collect, c;
	wb_flushsub(wb);
	collect = wb_collect(wb, 0);
	while (s < end && (c = escread(&s, d)) >= 0)
		wb_putc(wb, c, d);
	wb_collect(wb, collect);
}

/* return the size of \(hy if appended to wb */
int wb_dashwid(struct wb *wb)
{
	struct glyph *g = dev_glyph("hy", wb->f);
	return g ? font_gwid(g->font, dev_font(wb->f), wb->s, g->wid) : 0;
}