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Date:: Fri Jul 16 11:26:34 2021 UTC
Message:: emojified link lines!!
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1 /*
2  * Copyright (c) 2021 Omar Polo <op@omarpolo.com>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 /*
18  * Ncurses UI for telescope.
19  *
20  * Text scrolling
21  * ==============
22  *
23  * ncurses allows you to scroll a window, but when a line goes out of
24  * the visible area it's forgotten.  We keep a list of formatted lines
25  * (``visual lines'') that we know fits in the window, and draw them.
26  *
27  * This means that on every resize we have to clear our list of lines
28  * and re-render everything.  A clever approach would be to do this
29  * ``on-demand'', but it's still missing.
30  *
31  */
32 
33 #include <assert.h>
34 #include <curses.h>
35 #include <event.h>
36 #include <locale.h>
37 #include <signal.h>
38 #include <stdarg.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <unistd.h>
42 
43 #include "defaults.h"
44 #include "minibuffer.h"
45 #include "telescope.h"
46 #include "ui.h"
47 #include "utf8.h"
48 
49 static struct event	stdioev, winchev;
50 
51 static void		 restore_curs_x(struct buffer *);
52 
53 static struct vline	*nth_line(struct buffer*, size_t);
54 static int		 readkey(void);
55 static void		 dispatch_stdio(int, short, void*);
56 static void		 handle_clear_echoarea(int, short, void*);
57 static void		 handle_resize(int, short, void*);
58 static void		 handle_resize_nodelay(int, short, void*);
59 static void		 rearrange_windows(void);
60 static int		 wrap_page(struct buffer*, int);
61 static void		 print_vline(int, int, WINDOW*, struct vline*);
62 static void		 redraw_tabline(void);
63 static void		 redraw_window(WINDOW*, int, int, int, struct buffer*);
64 static void		 redraw_help(void);
65 static void		 redraw_body(struct tab*);
66 static void		 redraw_modeline(struct tab*);
67 static void		 redraw_minibuffer(void);
68 static void		 do_redraw_echoarea(void);
69 static void		 do_redraw_minibuffer(void);
70 static void		 do_redraw_minibuffer_compl(void);
71 static void		 place_cursor(int);
72 static void		 redraw_tab(struct tab*);
73 static void		 emit_help_item(char*, void*);
74 static void		 rec_compute_help(struct kmap*, char*, size_t);
75 static void		 recompute_help(void);
76 static void		 update_loading_anim(int, short, void*);
77 static void		 stop_loading_anim(struct tab*);
78 
79 static int		 should_rearrange_windows;
80 static int		 too_small;
81 static int		 x_offset;
82 
83 struct thiskey thiskey;
84 
85 static struct event	resizeev;
86 static struct timeval	resize_timer = { 0, 250000 };
87 
88 static WINDOW	*tabline, *body, *modeline, *echoarea, *minibuffer;
89 
90 int			 body_lines, body_cols;
91 
92 static WINDOW		*help;
93 static struct buffer	 helpwin;
94 static int		 help_lines, help_cols;
95 
96 static int		 side_window;
97 
98 static struct event	clechoev;
99 static struct timeval	clechoev_timer = { 5, 0 };
100 static struct timeval	loadingev_timer = { 0, 250000 };
101 
102 static uint32_t		 tab_counter;
103 
104 static char	keybuf[64];
105 
106 struct kmap global_map,
107 	minibuffer_map,
108 	*current_map,
109 	*base_map;
110 
111 int in_minibuffer;
112 
113 static inline void
114 update_x_offset(void)
115 {
116 	if (olivetti_mode && fill_column < body_cols)
117 		x_offset = (body_cols - fill_column)/2;
118 	else
119 		x_offset = 0;
120 }
121 
122 void
123 save_excursion(struct excursion *place, struct buffer *buffer)
124 {
125 	place->curs_x = buffer->curs_x;
126 	place->curs_y = buffer->curs_y;
127 	place->line_off = buffer->line_off;
128 	place->current_line = buffer->current_line;
129 	place->cpoff = buffer->cpoff;
130 }
131 
132 void
133 restore_excursion(struct excursion *place, struct buffer *buffer)
134 {
135 	buffer->curs_x = place->curs_x;
136 	buffer->curs_y = place->curs_y;
137 	buffer->line_off = place->line_off;
138 	buffer->current_line = place->current_line;
139 	buffer->cpoff = place->cpoff;
140 }
141 
142 static void
143 restore_curs_x(struct buffer *buffer)
144 {
145 	struct vline	*vl;
146 	const char	*prfx;
147 
148 	vl = buffer->current_line;
149 	if (vl == NULL || vl->line == NULL)
150 		buffer->curs_x = buffer->cpoff = 0;
151 	else if (vl->parent->data != NULL)
152 		buffer->curs_x = utf8_snwidth(vl->parent->data+1, buffer->cpoff) + 1;
153 	else
154 		buffer->curs_x = utf8_snwidth(vl->line, buffer->cpoff);
155 
156 	buffer->curs_x += x_offset;
157 
158 	if (vl != NULL) {
159 		prfx = line_prefixes[vl->parent->type].prfx1;
160 		buffer->curs_x += utf8_swidth(prfx);
161 	}
162 }
163 
164 void
165 global_key_unbound(void)
166 {
167 	message("%s is undefined", keybuf);
168 }
169 
170 static struct vline *
171 nth_line(struct buffer *buffer, size_t n)
172 {
173 	struct vline	*vl;
174 	size_t		 i;
175 
176 	i = 0;
177 	TAILQ_FOREACH(vl, &buffer->head, vlines) {
178 		if (i == n)
179 			return vl;
180 		i++;
181 	}
182 
183 	/* unreachable */
184 	abort();
185 }
186 
187 struct tab *
188 current_tab(void)
189 {
190 	struct tab *t;
191 
192 	TAILQ_FOREACH(t, &tabshead, tabs) {
193 		if (t->flags & TAB_CURRENT)
194 			return t;
195 	}
196 
197 	/* unreachable */
198 	abort();
199 }
200 
201 struct buffer *
202 current_buffer(void)
203 {
204 	if (in_minibuffer)
205 		return &ministate.buffer;
206 	return &current_tab()->buffer;
207 }
208 
209 static int
210 readkey(void)
211 {
212 	uint32_t state = 0;
213 
214 	if ((thiskey.key = wgetch(body)) == ERR)
215 		return 0;
216 
217 	thiskey.meta = thiskey.key == 27;
218 	if (thiskey.meta) {
219 		thiskey.key = wgetch(body);
220 		if (thiskey.key == ERR || thiskey.key == 27) {
221 			thiskey.meta = 0;
222 			thiskey.key = 27;
223 		}
224 	}
225 
226 	thiskey.cp = 0;
227 	if ((unsigned int)thiskey.key < UINT8_MAX) {
228 		while (1) {
229 			if (!utf8_decode(&state, &thiskey.cp, (uint8_t)thiskey.key))
230 				break;
231 			if ((thiskey.key = wgetch(body)) == ERR) {
232 				message("Error decoding user input");
233 				return 0;
234 			}
235 		}
236 	}
237 
238 	return 1;
239 }
240 
241 static void
242 dispatch_stdio(int fd, short ev, void *d)
243 {
244 	struct keymap	*k;
245 	const char	*keyname;
246 	char		 tmp[5] = {0};
247 
248 	/* TODO: schedule a redraw? */
249 	if (too_small)
250 		return;
251 
252 	if (!readkey())
253 		return;
254 
255 	if (keybuf[0] != '\0')
256 		strlcat(keybuf, " ", sizeof(keybuf));
257 	if (thiskey.meta)
258 		strlcat(keybuf, "M-", sizeof(keybuf));
259 	if (thiskey.cp != 0) {
260 		utf8_encode(thiskey.cp, tmp);
261 		strlcat(keybuf, tmp, sizeof(keybuf));
262 	} else if ((keyname = unkbd(thiskey.key)) != NULL) {
263 		strlcat(keybuf, keyname, sizeof(keybuf));
264 	} else {
265 		tmp[0] = thiskey.key;
266 		strlcat(keybuf, tmp, sizeof(keybuf));
267 	}
268 
269 	TAILQ_FOREACH(k, &current_map->m, keymaps) {
270 		if (k->meta == thiskey.meta &&
271 		    k->key == thiskey.key) {
272 			if (k->fn == NULL)
273 				current_map = &k->map;
274 			else {
275 				current_map = base_map;
276 				strlcpy(keybuf, "", sizeof(keybuf));
277 				k->fn(current_buffer());
278 			}
279 			goto done;
280 		}
281 	}
282 
283 	if (current_map->unhandled_input != NULL)
284 		current_map->unhandled_input();
285 	else
286 		global_key_unbound();
287 
288 	strlcpy(keybuf, "", sizeof(keybuf));
289 	current_map = base_map;
290 
291 done:
292 	if (side_window)
293 		recompute_help();
294 
295 	if (should_rearrange_windows)
296 		rearrange_windows();
297 	redraw_tab(current_tab());
298 }
299 
300 static void
301 handle_clear_echoarea(int fd, short ev, void *d)
302 {
303 	free(ministate.curmesg);
304 	ministate.curmesg = NULL;
305 
306 	redraw_minibuffer();
307 	place_cursor(0);
308 }
309 
310 static void
311 handle_resize(int sig, short ev, void *d)
312 {
313 	if (event_pending(&resizeev, EV_TIMEOUT, NULL)) {
314 		event_del(&resizeev);
315 	}
316 	evtimer_set(&resizeev, handle_resize_nodelay, NULL);
317 	evtimer_add(&resizeev, &resize_timer);
318 }
319 
320 static void
321 handle_resize_nodelay(int s, short ev, void *d)
322 {
323 	endwin();
324 	refresh();
325 	clear();
326 
327 	rearrange_windows();
328 }
329 
330 static void
331 rearrange_windows(void)
332 {
333 	struct tab	*tab;
334 	int		 lines;
335 
336 	should_rearrange_windows = 0;
337 
338 	lines = LINES;
339 
340 	if ((too_small = lines < 15)) {
341 		erase();
342 		printw("Window too small.");
343 		refresh();
344 		return;
345 	}
346 
347 	/* move and resize the windows, in reverse order! */
348 
349 	if (in_minibuffer == MB_COMPREAD) {
350 		mvwin(minibuffer, lines-10, 0);
351 		wresize(minibuffer, 10, COLS);
352 		lines -= 10;
353 
354 		wrap_page(&ministate.compl.buffer, COLS);
355 	}
356 
357 	mvwin(echoarea, --lines, 0);
358 	wresize(echoarea, 1, COLS);
359 
360 	mvwin(modeline, --lines, 0);
361 	wresize(modeline, 1, COLS);
362 
363 	body_lines = --lines;
364 	body_cols = COLS;
365 
366 	if (side_window) {
367 		help_cols = 0.3 * COLS;
368 		help_lines = lines;
369 		mvwin(help, 1, 0);
370 		wresize(help, help_lines, help_cols);
371 
372 		wrap_page(&helpwin, help_cols);
373 
374 		body_cols = COLS - help_cols - 1;
375 		mvwin(body, 1, help_cols);
376 	} else
377 		mvwin(body, 1, 0);
378 
379 	update_x_offset();
380 	wresize(body, body_lines, body_cols);
381 
382 	wresize(tabline, 1, COLS);
383 
384 	tab = current_tab();
385 
386 	wrap_page(&tab->buffer, body_cols);
387 	redraw_tab(tab);
388 }
389 
390 static int
391 wrap_page(struct buffer *buffer, int width)
392 {
393 	struct line		*l;
394 	const struct line	*top_orig, *orig;
395 	struct vline		*vl;
396 	int			 pre_width;
397 	const char		*prfx;
398 
399 	top_orig = buffer->top_line == NULL ? NULL : buffer->top_line->parent;
400 	orig = buffer->current_line == NULL ? NULL : buffer->current_line->parent;
401 
402 	buffer->top_line = NULL;
403 	buffer->current_line = NULL;
404 
405 	buffer->force_redraw = 1;
406 	buffer->curs_y = 0;
407 	buffer->line_off = 0;
408 
409 	empty_vlist(buffer);
410 
411 	TAILQ_FOREACH(l, &buffer->page.head, lines) {
412 		prfx = line_prefixes[l->type].prfx1;
413 		switch (l->type) {
414 		case LINE_TEXT:
415 		case LINE_LINK:
416 		case LINE_TITLE_1:
417 		case LINE_TITLE_2:
418 		case LINE_TITLE_3:
419 		case LINE_ITEM:
420 		case LINE_QUOTE:
421 		case LINE_PRE_START:
422 		case LINE_PRE_END:
423 			wrap_text(buffer, prfx, l, MIN(fill_column, width));
424 			break;
425 		case LINE_PRE_CONTENT:
426 			if (olivetti_mode)
427 				pre_width = MIN(fill_column, width);
428 			else
429 				pre_width = width;
430 			hardwrap_text(buffer, l, pre_width);
431 			break;
432 		case LINE_COMPL:
433 		case LINE_COMPL_CURRENT:
434 			wrap_one(buffer, prfx, l, width);
435 			break;
436 		}
437 
438 		if (top_orig == l && buffer->top_line == NULL) {
439 			buffer->line_off = buffer->line_max-1;
440 			buffer->top_line = TAILQ_LAST(&buffer->head, vhead);
441 
442 			while (1) {
443 				vl = TAILQ_PREV(buffer->top_line, vhead, vlines);
444 				if (vl == NULL || vl->parent != orig)
445 					break;
446 				buffer->top_line = vl;
447 				buffer->line_off--;
448 			}
449 		}
450 
451 		if (orig == l && buffer->current_line == NULL) {
452 			buffer->current_line = TAILQ_LAST(&buffer->head, vhead);
453 
454 			while (1) {
455 				vl = TAILQ_PREV(buffer->current_line, vhead, vlines);
456 				if (vl == NULL || vl->parent != orig)
457 					break;
458 				buffer->current_line = vl;
459 			}
460 		}
461 	}
462 
463         if (buffer->current_line == NULL)
464 		buffer->current_line = TAILQ_FIRST(&buffer->head);
465 
466 	if (buffer->top_line == NULL)
467 		buffer->top_line = buffer->current_line;
468 
469 	return 1;
470 }
471 
472 /*
473  * Core part of the rendering.  It prints a vline starting from the
474  * current cursor position.  Printing a vline consists of skipping
475  * `off' columns (for olivetti-mode), print the correct prefix (which
476  * may be the emoji in case of emojified links-lines), printing the
477  * text itself, filling until width - off and filling off columns
478  * again.
479  */
480 static void
481 print_vline(int off, int width, WINDOW *window, struct vline *vl)
482 {
483 	/*
484 	 * Believe me or not, I've seen emoji ten code points long!
485 	 * That means, to stay large, 4*10 bytes + NUL.
486 	 */
487 	char emojibuf[41] = {0};
488 	char *space, *t;
489 	const char *text, *prfx;
490 	struct line_face *f;
491 	int i, left, x, y, emojified, cont;
492 	long len = sizeof(emojibuf);
493 
494 	f = &line_faces[vl->parent->type];
495 
496 	/* unused, set by getyx */
497 	(void)y;
498 
499 	cont = vl->flags & L_CONTINUATION;
500 	if (!cont)
501 		prfx = line_prefixes[vl->parent->type].prfx1;
502 	else
503 		prfx = line_prefixes[vl->parent->type].prfx2;
504 
505 	text = vl->line;
506 	if (text == NULL)
507 		text = "";
508 
509 	wattr_on(window, body_face.left, NULL);
510 	for (i = 0; i < off; i++)
511 		waddch(window, ' ');
512 	wattr_off(window, body_face.left, NULL);
513 
514 	wattr_on(window, f->prefix, NULL);
515 	emojified = 0;
516 	space = vl->parent->data;
517 	if (vl->parent->type == LINE_LINK && space != NULL) {
518 		emojified = 1;
519 		if (cont) {
520 			len = utf8_swidth_between(vl->parent->line, space) + 1;
521 			for (i = 0; i < len; ++i)
522 				wprintw(window, " ");
523 		} else {
524 			strlcpy(emojibuf, text, sizeof(emojibuf));
525 			if ((t = strchr(emojibuf, ' ')) != NULL)
526 				*t = '\0';
527 			wprintw(window, "%s ", emojibuf);
528 		}
529 	} else {
530 		wprintw(window, "%s", prfx);
531 	}
532 	wattr_off(window, f->prefix, NULL);
533 
534 	wattr_on(window, f->text, NULL);
535 	if (emojified && !cont)
536 		wprintw(window, "%s", text + (space - vl->parent->line) + 1);
537 	else
538 		wprintw(window, "%s", text);
539 	wattr_off(window, f->text, NULL);
540 
541 	getyx(window, y, x);
542 
543 	left = width - x;
544 
545 	wattr_on(window, f->trail, NULL);
546 	for (i = 0; i < left - off; ++i)
547 		waddch(window, ' ');
548 	wattr_off(window, f->trail, NULL);
549 
550 	wattr_on(window, body_face.right, NULL);
551 	for (i = 0; i < off; i++)
552 		waddch(window, ' ');
553 	wattr_off(window, body_face.right, NULL);
554 
555 }
556 
557 static void
558 redraw_tabline(void)
559 {
560 	struct tab	*tab;
561 	size_t		 toskip, ots, tabwidth, space, x;
562 	int		 current, y, truncated;
563 	const char	*title;
564 	char		 buf[25];
565 
566 	x = 0;
567 
568 	/* unused, but setted by a getyx */
569 	(void)y;
570 
571 	tabwidth = sizeof(buf)+1;
572 	space = COLS-2;
573 
574 	toskip = 0;
575 	TAILQ_FOREACH(tab, &tabshead, tabs) {
576 		toskip++;
577 		if (tab->flags & TAB_CURRENT)
578 			break;
579 	}
580 
581 	if (toskip * tabwidth < space)
582 		toskip = 0;
583 	else {
584 		ots = toskip;
585 		toskip--;
586                 while (toskip != 0 &&
587 		    (ots - toskip+1) * tabwidth < space)
588 			toskip--;
589 	}
590 
591 	werase(tabline);
592 	wattr_on(tabline, tab_face.background, NULL);
593 	wprintw(tabline, toskip == 0 ? " " : "<");
594 	wattr_off(tabline, tab_face.background, NULL);
595 
596 	truncated = 0;
597 	TAILQ_FOREACH(tab, &tabshead, tabs) {
598 		if (truncated)
599 			break;
600 		if (toskip != 0) {
601 			toskip--;
602 			continue;
603 		}
604 
605 		getyx(tabline, y, x);
606 		if (x + sizeof(buf)+2 >= (size_t)COLS)
607 			truncated = 1;
608 
609 		current = tab->flags & TAB_CURRENT;
610 
611 		if (*(title = tab->buffer.page.title) == '\0')
612 			title = tab->hist_cur->h;
613 
614 		if (tab->flags & TAB_URGENT)
615 			strlcpy(buf, "!", sizeof(buf));
616 		else
617 			strlcpy(buf, " ", sizeof(buf));
618 
619                 if (strlcat(buf, title, sizeof(buf)) >= sizeof(buf)) {
620 			/* truncation happens */
621 			strlcpy(&buf[sizeof(buf)-4], "...", 4);
622 		} else {
623 			/* pad with spaces */
624 			while (strlcat(buf, "    ", sizeof(buf)) < sizeof(buf))
625 				/* nop */ ;
626 		}
627 
628 		if (current)
629 			wattr_on(tabline, tab_face.current, NULL);
630 		else
631 			wattr_on(tabline, tab_face.tab, NULL);
632 
633 		wprintw(tabline, "%s", buf);
634 		if (TAILQ_NEXT(tab, tabs) != NULL)
635 			wprintw(tabline, " ");
636 
637 		if (current)
638 			wattr_off(tabline, tab_face.current, NULL);
639 		else
640 			wattr_off(tabline, tab_face.tab, NULL);
641 	}
642 
643 	wattr_on(tabline, tab_face.background, NULL);
644 	for (; x < (size_t)COLS; ++x)
645 		waddch(tabline, ' ');
646 	if (truncated)
647 		mvwprintw(tabline, 0, COLS-1, ">");
648 	wattr_off(tabline, tab_face.background, NULL);
649 }
650 
651 /*
652  * Compute the first visible line around vl.  Try to search forward
653  * until the end of the buffer; if a visible line is not found, search
654  * backward.  Return NULL if no viable line was found.
655  */
656 struct vline *
657 adjust_line(struct vline *vl, struct buffer *buffer)
658 {
659 	struct vline *t;
660 
661 	if (vl == NULL)
662 		return NULL;
663 
664 	if (!(vl->parent->flags & L_HIDDEN))
665 		return vl;
666 
667 	/* search forward */
668 	for (t = vl;
669 	     t != NULL && t->parent->flags & L_HIDDEN;
670 	     t = TAILQ_NEXT(t, vlines))
671 		;		/* nop */
672 
673 	if (t != NULL)
674 		return t;
675 
676 	/* search backward */
677 	for (t = vl;
678 	     t != NULL && t->parent->flags & L_HIDDEN;
679 	     t = TAILQ_PREV(t, vhead, vlines))
680 		;		/* nop */
681 
682 	return t;
683 }
684 
685 static void
686 redraw_window(WINDOW *win, int off, int height, int width, struct buffer *buffer)
687 {
688         struct vline	*vl;
689 	int		 l, onscreen;
690 
691 	restore_curs_x(buffer);
692 
693 	/*
694 	 * TODO: ignoring buffer->force_update and always
695 	 * re-rendering.  In theory we can recompute the y position
696 	 * without a re-render, and optimize here.  It's not the only
697 	 * optimisation possible here, wscrl wolud also be an
698 	 * interesting one.
699 	 */
700 
701 again:
702 	werase(win);
703 	buffer->curs_y = 0;
704 
705 	if (TAILQ_EMPTY(&buffer->head))
706 		goto end;
707 
708 	if (buffer->top_line == NULL)
709 		buffer->top_line = TAILQ_FIRST(&buffer->head);
710 
711 	buffer->top_line = adjust_line(buffer->top_line, buffer);
712 	if (buffer->top_line == NULL)
713 		goto end;
714 
715 	buffer->current_line = adjust_line(buffer->current_line, buffer);
716 
717 	l = 0;
718 	onscreen = 0;
719 	for (vl = buffer->top_line; vl != NULL; vl = TAILQ_NEXT(vl, vlines)) {
720 		if (vl->parent->flags & L_HIDDEN)
721 			continue;
722 
723 		wmove(win, l, 0);
724 		print_vline(off, width, win, vl);
725 
726 		if (vl == buffer->current_line)
727 			onscreen = 1;
728 
729 		if (!onscreen)
730 			buffer->curs_y++;
731 
732 		l++;
733 		if (l == height)
734 			break;
735 	}
736 
737 	if (!onscreen) {
738 		for (; vl != NULL; vl = TAILQ_NEXT(vl, vlines)) {
739 			if (vl == buffer->current_line)
740 				break;
741 			if (vl->parent->flags & L_HIDDEN)
742 				continue;
743 			buffer->line_off++;
744 			buffer->top_line = TAILQ_NEXT(buffer->top_line, vlines);
745 		}
746 
747 		if (vl != NULL)
748 			goto again;
749 	}
750 
751 	buffer->last_line_off = buffer->line_off;
752 	buffer->force_redraw = 0;
753 end:
754 	wmove(win, buffer->curs_y, buffer->curs_x);
755 }
756 
757 static void
758 redraw_help(void)
759 {
760 	redraw_window(help, 0, help_lines, help_cols, &helpwin);
761 }
762 
763 static void
764 redraw_body(struct tab *tab)
765 {
766 	static struct tab *last_tab;
767 
768 	if (last_tab != tab)
769 		tab->buffer.force_redraw =1;
770 	last_tab = tab;
771 
772 	redraw_window(body, x_offset, body_lines, body_cols, &tab->buffer);
773 }
774 
775 static inline char
776 trust_status_char(enum trust_state ts)
777 {
778 	switch (ts) {
779 	case TS_UNKNOWN:	return 'u';
780 	case TS_UNTRUSTED:	return '!';
781 	case TS_TEMP_TRUSTED:	return '!';
782 	case TS_TRUSTED:	return 'v';
783 	case TS_VERIFIED:	return 'V';
784 	default:		return 'X';
785 	}
786 }
787 
788 static void
789 redraw_modeline(struct tab *tab)
790 {
791 	double		 pct;
792 	int		 x, y, max_x, max_y;
793 	const char	*mode = tab->buffer.page.name;
794 	const char	*spin = "-\\|/";
795 
796 	werase(modeline);
797 	wattr_on(modeline, modeline_face.background, NULL);
798 	wmove(modeline, 0, 0);
799 
800 	wprintw(modeline, "-%c%c %s ",
801 	    spin[tab->loading_anim_step],
802 	    trust_status_char(tab->trust),
803 	    mode == NULL ? "(none)" : mode);
804 
805 	pct = (tab->buffer.line_off + tab->buffer.curs_y) * 100.0
806 		/ tab->buffer.line_max;
807 
808 	if (tab->buffer.line_max <= (size_t)body_lines)
809                 wprintw(modeline, "All ");
810 	else if (tab->buffer.line_off == 0)
811                 wprintw(modeline, "Top ");
812 	else if (tab->buffer.line_off + body_lines >= tab->buffer.line_max)
813 		wprintw(modeline, "Bottom ");
814 	else
815 		wprintw(modeline, "%.0f%% ", pct);
816 
817 	wprintw(modeline, "%d/%d %s ",
818 	    tab->buffer.line_off + tab->buffer.curs_y,
819 	    tab->buffer.line_max,
820 	    tab->hist_cur->h);
821 
822 	getyx(modeline, y, x);
823 	getmaxyx(modeline, max_y, max_x);
824 
825 	(void)y;
826 	(void)max_y;
827 
828 	for (; x < max_x; ++x)
829 		waddstr(modeline, "-");
830 
831 	wattr_off(modeline, modeline_face.background, NULL);
832 }
833 
834 static void
835 redraw_minibuffer(void)
836 {
837 	wattr_on(echoarea, minibuffer_face.background, NULL);
838 	werase(echoarea);
839 
840 	if (in_minibuffer)
841 		do_redraw_minibuffer();
842 	else
843 		do_redraw_echoarea();
844 
845 	if (in_minibuffer == MB_COMPREAD)
846 		do_redraw_minibuffer_compl();
847 
848 	wattr_off(echoarea, minibuffer_face.background, NULL);
849 }
850 
851 static void
852 do_redraw_echoarea(void)
853 {
854 	struct tab *tab;
855 
856 	if (ministate.curmesg != NULL)
857                 wprintw(echoarea, "%s", ministate.curmesg);
858 	else if (*keybuf != '\0')
859 		waddstr(echoarea, keybuf);
860 	else {
861 		/* If nothing else, show the URL at point */
862 		tab = current_tab();
863 		if (tab->buffer.current_line != NULL &&
864 		    tab->buffer.current_line->parent->type == LINE_LINK)
865 			waddstr(echoarea,
866 			    tab->buffer.current_line->parent->alt);
867 	}
868 }
869 
870 static void
871 do_redraw_minibuffer(void)
872 {
873 	size_t		 off_y, off_x = 0;
874 	const char	*start, *c;
875 
876 	/* unused, set by getyx */
877 	(void)off_y;
878 
879 	wmove(echoarea, 0, 0);
880 
881 	if (in_minibuffer == MB_COMPREAD)
882 		wprintw(echoarea, "(%2d) ",
883 		    ministate.compl.buffer.line_max);
884 
885 	wprintw(echoarea, "%s", ministate.prompt);
886 	if (ministate.hist_cur != NULL)
887 		wprintw(echoarea, "(%zu/%zu) ",
888 		    ministate.hist_off + 1,
889 		    ministate.history->len);
890 
891 	getyx(echoarea, off_y, off_x);
892 
893 	start = ministate.hist_cur != NULL
894 		? ministate.hist_cur->h
895 		: ministate.buf;
896 	c = utf8_nth(ministate.buffer.current_line->line,
897 	    ministate.buffer.cpoff);
898 	while (utf8_swidth_between(start, c) > (size_t)COLS/2) {
899 		start = utf8_next_cp(start);
900 	}
901 
902 	waddstr(echoarea, start);
903 
904 	if (ministate.curmesg != NULL)
905 		wprintw(echoarea, " [%s]", ministate.curmesg);
906 
907 	wmove(echoarea, 0, off_x + utf8_swidth_between(start, c));
908 }
909 
910 static void
911 do_redraw_minibuffer_compl(void)
912 {
913 	redraw_window(minibuffer, 0, 10, body_cols,
914 	    &ministate.compl.buffer);
915 }
916 
917 /*
918  * Place the cursor in the right ncurses window.  If soft is 1, use
919  * wnoutrefresh (which shouldn't cause any I/O); otherwise use
920  * wrefresh.
921  */
922 static void
923 place_cursor(int soft)
924 {
925 	int (*touch)(WINDOW *);
926 
927 	if (soft)
928 		touch = wnoutrefresh;
929 	else
930 		touch = wrefresh;
931 
932 	if (in_minibuffer) {
933 		touch(body);
934 		touch(echoarea);
935 	} else {
936 		touch(echoarea);
937 		touch(body);
938 	}
939 }
940 
941 static void
942 redraw_tab(struct tab *tab)
943 {
944 	if (too_small)
945 		return;
946 
947 	if (side_window) {
948 		redraw_help();
949 		wnoutrefresh(help);
950 	}
951 
952 	redraw_tabline();
953 	redraw_body(tab);
954 	redraw_modeline(tab);
955 	redraw_minibuffer();
956 
957 	wnoutrefresh(tabline);
958 	wnoutrefresh(modeline);
959 
960 	if (in_minibuffer == MB_COMPREAD)
961 		wnoutrefresh(minibuffer);
962 
963 	place_cursor(1);
964 
965 	doupdate();
966 }
967 
968 static void
969 emit_help_item(char *prfx, void *fn)
970 {
971 	struct line	*l;
972 	struct cmd	*cmd;
973 
974 	for (cmd = cmds; cmd->cmd != NULL; ++cmd) {
975 		if (fn == cmd->fn)
976 			break;
977 	}
978 	assert(cmd != NULL);
979 
980 	if ((l = calloc(1, sizeof(*l))) == NULL)
981 		abort();
982 
983 	l->type = LINE_TEXT;
984 	l->alt = NULL;
985 
986 	asprintf(&l->line, "%s %s", prfx, cmd->cmd);
987 
988 	if (TAILQ_EMPTY(&helpwin.page.head))
989 		TAILQ_INSERT_HEAD(&helpwin.page.head, l, lines);
990 	else
991 		TAILQ_INSERT_TAIL(&helpwin.page.head, l, lines);
992 }
993 
994 static void
995 rec_compute_help(struct kmap *keymap, char *prfx, size_t len)
996 {
997 	struct keymap	*k;
998 	char		 p[32];
999 	const char	*kn;
1000 
1001 	TAILQ_FOREACH(k, &keymap->m, keymaps) {
1002 		strlcpy(p, prfx, sizeof(p));
1003 		if (*p != '\0')
1004 			strlcat(p, " ", sizeof(p));
1005 		if (k->meta)
1006 			strlcat(p, "M-", sizeof(p));
1007 		if ((kn = unkbd(k->key)) != NULL)
1008 			strlcat(p, kn, sizeof(p));
1009 		else
1010 			strlcat(p, keyname(k->key), sizeof(p));
1011 
1012 		if (k->fn == NULL)
1013 			rec_compute_help(&k->map, p, sizeof(p));
1014 		else
1015 			emit_help_item(p, k->fn);
1016 	}
1017 }
1018 
1019 static void
1020 recompute_help(void)
1021 {
1022 	char	p[32] = { 0 };
1023 
1024 	empty_vlist(&helpwin);
1025 	empty_linelist(&helpwin);
1026 	rec_compute_help(current_map, p, sizeof(p));
1027 	wrap_page(&helpwin, help_cols);
1028 }
1029 
1030 void
1031 vmessage(const char *fmt, va_list ap)
1032 {
1033 	if (evtimer_pending(&clechoev, NULL))
1034 		evtimer_del(&clechoev);
1035 
1036 	free(ministate.curmesg);
1037 	ministate.curmesg = NULL;
1038 
1039 	if (fmt != NULL) {
1040 		evtimer_set(&clechoev, handle_clear_echoarea, NULL);
1041 		evtimer_add(&clechoev, &clechoev_timer);
1042 
1043 		/* TODO: what to do if the allocation fails here? */
1044 		if (vasprintf(&ministate.curmesg, fmt, ap) == -1)
1045 			ministate.curmesg = NULL;
1046 	}
1047 
1048 	redraw_minibuffer();
1049         place_cursor(0);
1050 }
1051 
1052 void
1053 message(const char *fmt, ...)
1054 {
1055 	va_list ap;
1056 
1057 	va_start(ap, fmt);
1058 	vmessage(fmt, ap);
1059 	va_end(ap);
1060 }
1061 
1062 void
1063 start_loading_anim(struct tab *tab)
1064 {
1065 	if (tab->loading_anim)
1066 		return;
1067 	tab->loading_anim = 1;
1068 	evtimer_set(&tab->loadingev, update_loading_anim, tab);
1069 	evtimer_add(&tab->loadingev, &loadingev_timer);
1070 }
1071 
1072 static void
1073 update_loading_anim(int fd, short ev, void *d)
1074 {
1075 	struct tab	*tab = d;
1076 
1077 	tab->loading_anim_step = (tab->loading_anim_step+1)%4;
1078 
1079 	if (tab->flags & TAB_CURRENT) {
1080 		redraw_modeline(tab);
1081 		wrefresh(modeline);
1082 		wrefresh(body);
1083 		if (in_minibuffer)
1084 			wrefresh(echoarea);
1085 	}
1086 
1087 	evtimer_add(&tab->loadingev, &loadingev_timer);
1088 }
1089 
1090 static void
1091 stop_loading_anim(struct tab *tab)
1092 {
1093 	if (!tab->loading_anim)
1094 		return;
1095 	evtimer_del(&tab->loadingev);
1096 	tab->loading_anim = 0;
1097 	tab->loading_anim_step = 0;
1098 
1099 	if (!(tab->flags & TAB_CURRENT))
1100 		return;
1101 
1102 	redraw_modeline(tab);
1103 
1104 	wrefresh(modeline);
1105 	wrefresh(body);
1106 	if (in_minibuffer)
1107 		wrefresh(echoarea);
1108 }
1109 
1110 void
1111 load_url_in_tab(struct tab *tab, const char *url)
1112 {
1113 	message("Loading %s...", url);
1114 	start_loading_anim(tab);
1115 	load_url(tab, url);
1116 
1117 	tab->buffer.curs_x = 0;
1118 	tab->buffer.curs_y = 0;
1119 	redraw_tab(tab);
1120 }
1121 
1122 void
1123 switch_to_tab(struct tab *tab)
1124 {
1125 	struct tab	*t;
1126 
1127 	TAILQ_FOREACH(t, &tabshead, tabs) {
1128 		t->flags &= ~TAB_CURRENT;
1129 	}
1130 
1131 	tab->flags |= TAB_CURRENT;
1132 	tab->flags &= ~TAB_URGENT;
1133 }
1134 
1135 unsigned int
1136 tab_new_id(void)
1137 {
1138 	return tab_counter++;
1139 }
1140 
1141 struct tab *
1142 new_tab(const char *url)
1143 {
1144 	struct tab	*tab;
1145 
1146 	if ((tab = calloc(1, sizeof(*tab))) == NULL) {
1147 		event_loopbreak();
1148 		return NULL;
1149 	}
1150 	tab->fd = -1;
1151 
1152 	TAILQ_INIT(&tab->hist.head);
1153 
1154 	TAILQ_INIT(&tab->buffer.head);
1155 
1156 	tab->id = tab_new_id();
1157 	switch_to_tab(tab);
1158 
1159 	if (TAILQ_EMPTY(&tabshead))
1160 		TAILQ_INSERT_HEAD(&tabshead, tab, tabs);
1161 	else
1162 		TAILQ_INSERT_TAIL(&tabshead, tab, tabs);
1163 
1164 	load_url_in_tab(tab, url);
1165 	return tab;
1166 }
1167 
1168 int
1169 ui_print_colors(void)
1170 {
1171 	int colors = 0, pairs = 0, can_change = 0;
1172 	int columns = 16, lines, color, i, j;
1173 
1174 	initscr();
1175 	if (has_colors()) {
1176 		start_color();
1177 		use_default_colors();
1178 
1179 		colors = COLORS;
1180 		pairs = COLOR_PAIRS;
1181 		can_change = can_change_color();
1182 	}
1183 	endwin();
1184 
1185 	printf("Term info:\n");
1186 	printf("TERM=%s COLORS=%d COLOR_PAIRS=%d can_change_colors=%d\n",
1187 	    getenv("TERM"), colors, pairs, can_change);
1188 	printf("\n");
1189 
1190 	if (colors == 0) {
1191 		printf("No color support\n");
1192 		return 0;
1193 	}
1194 
1195 	printf("Available colors:\n\n");
1196 	lines = (colors - 1) / columns + 1;
1197 	color = 0;
1198 	for (i = 0; i < lines; ++i) {
1199 		for (j = 0; j < columns; ++j, ++color) {
1200 			printf("\033[0;38;5;%dm %03d", color, color);
1201 		}
1202 		printf("\n");
1203 	}
1204 
1205 	printf("\033[0m");
1206 	fflush(stdout);
1207 	return 0;
1208 }
1209 
1210 int
1211 ui_init()
1212 {
1213 	setlocale(LC_ALL, "");
1214 
1215 	TAILQ_INIT(&eecmd_history.head);
1216 	TAILQ_INIT(&ir_history.head);
1217 	TAILQ_INIT(&lu_history.head);
1218 
1219 	ministate.line.type = LINE_TEXT;
1220 	ministate.vline.parent = &ministate.line;
1221 	ministate.buffer.current_line = &ministate.vline;
1222 
1223 	/* initialize help window */
1224 	TAILQ_INIT(&helpwin.head);
1225 
1226 	base_map = &global_map;
1227 	current_map = &global_map;
1228 
1229 	initscr();
1230 
1231 	if (enable_colors) {
1232 		if (has_colors()) {
1233 			start_color();
1234 			use_default_colors();
1235 		} else
1236 			enable_colors = 0;
1237 	}
1238 
1239 	config_apply_style();
1240 
1241 	raw();
1242 	noecho();
1243 	nonl();
1244 	intrflush(stdscr, FALSE);
1245 
1246 	if ((tabline = newwin(1, COLS, 0, 0)) == NULL)
1247 		return 0;
1248 	if ((body = newwin(LINES - 3, COLS, 1, 0)) == NULL)
1249 		return 0;
1250 	if ((modeline = newwin(1, COLS, LINES-2, 0)) == NULL)
1251 		return 0;
1252 	if ((echoarea = newwin(1, COLS, LINES-1, 0)) == NULL)
1253 		return 0;
1254 	if ((minibuffer = newwin(1, COLS, LINES-1, 0)) == NULL)
1255 		return 0;
1256 	if ((help = newwin(1, 1, 1, 0)) == NULL)
1257 		return 0;
1258 
1259 	body_lines = LINES-3;
1260 	body_cols = COLS;
1261 
1262 	wbkgd(body, body_face.body);
1263 	wbkgd(echoarea, minibuffer_face.background);
1264 
1265 	update_x_offset();
1266 
1267 	keypad(body, TRUE);
1268 	scrollok(body, FALSE);
1269 
1270 	/* non-blocking input */
1271 	wtimeout(body, 0);
1272 
1273 	mvwprintw(body, 0, 0, "");
1274 
1275 	/*
1276 	 * Dummy so libevent2 won't complain that no event_base is set
1277 	 * when checking event_pending for the first time
1278 	 */
1279 	evtimer_set(&clechoev, handle_clear_echoarea, NULL);
1280 	evtimer_add(&clechoev, &clechoev_timer);
1281 	evtimer_set(&resizeev, handle_resize, NULL);
1282 	evtimer_add(&resizeev, &resize_timer);
1283 
1284 	event_set(&stdioev, 0, EV_READ | EV_PERSIST, dispatch_stdio, NULL);
1285 	event_add(&stdioev, NULL);
1286 
1287 	signal_set(&winchev, SIGWINCH, handle_resize, NULL);
1288 	signal_add(&winchev, NULL);
1289 
1290 	return 1;
1291 }
1292 
1293 void
1294 ui_on_tab_loaded(struct tab *tab)
1295 {
1296 	stop_loading_anim(tab);
1297 	message("Loaded %s", tab->hist_cur->h);
1298 
1299 	redraw_tabline();
1300 	wrefresh(tabline);
1301 	place_cursor(0);
1302 }
1303 
1304 void
1305 ui_on_tab_refresh(struct tab *tab)
1306 {
1307 	wrap_page(&tab->buffer, body_cols);
1308 	if (tab->flags & TAB_CURRENT)
1309 		redraw_tab(tab);
1310 	else
1311 		tab->flags |= TAB_URGENT;
1312 }
1313 
1314 const char *
1315 ui_keyname(int k)
1316 {
1317 	return keyname(k);
1318 }
1319 
1320 void
1321 ui_toggle_side_window(void)
1322 {
1323 	side_window = !side_window;
1324 	if (side_window)
1325 		recompute_help();
1326 
1327 	/*
1328 	 * ugly hack, but otherwise the window doesn't get updated
1329 	 * until I call rearrange_windows a second time (e.g. via
1330 	 * C-l).  I will be happy to know why something like this is
1331 	 * needed.
1332 	 */
1333 	rearrange_windows();
1334 	rearrange_windows();
1335 }
1336 
1337 void
1338 ui_schedule_redraw(void)
1339 {
1340 	should_rearrange_windows = 1;
1341 }
1342 
1343 void
1344 ui_require_input(struct tab *tab, int hide)
1345 {
1346 	/* TODO: hard-switching to another tab is ugly */
1347 	switch_to_tab(tab);
1348 
1349 	enter_minibuffer(ir_self_insert, ir_select, exit_minibuffer,
1350 	    &ir_history, NULL, NULL);
1351 	strlcpy(ministate.prompt, "Input required: ",
1352 	    sizeof(ministate.prompt));
1353 	redraw_tab(tab);
1354 }
1355 
1356 void
1357 ui_yornp(const char *prompt, void (*fn)(int, struct tab *),
1358     struct tab *data)
1359 {
1360 	yornp(prompt, fn, data);
1361 	redraw_tab(current_tab());
1362 }
1363 
1364 void
1365 ui_read(const char *prompt, void (*fn)(const char*, struct tab *),
1366     struct tab *data)
1367 {
1368 	completing_read(prompt, fn, data);
1369 	redraw_tab(current_tab());
1370 }
1371 
1372 void
1373 ui_suspend(void)
1374 {
1375 	endwin();
1376 
1377 	kill(getpid(), SIGSTOP);
1378 
1379 	refresh();
1380 	clear();
1381 	rearrange_windows();
1382 }
1383 
1384 void
1385 ui_end(void)
1386 {
1387 	endwin();
1388 }