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Date:: Fri Nov 5 18:18:02 2021 UTC
Message:: LINE_DOWNLOAD_INFO doesn't have an alt to render
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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 "compat.h"
34 
35 #include <assert.h>
36 #include <curses.h>
37 #include <locale.h>
38 #include <signal.h>
39 #include <stdarg.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <unistd.h>
43 
44 #include "defaults.h"
45 #include "minibuffer.h"
46 #include "session.h"
47 #include "telescope.h"
48 #include "ui.h"
49 #include "utf8.h"
50 
51 static struct event	stdioev, winchev;
52 
53 static void		 restore_curs_x(struct buffer *);
54 
55 static int		 readkey(void);
56 static void		 dispatch_stdio(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 void		 line_prefix_and_text(struct vline *, char *, size_t, const char **, const char **);
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_download(void);
65 static void		 redraw_help(void);
66 static void		 redraw_body(struct tab*);
67 static void		 redraw_modeline(struct tab*);
68 static void		 redraw_minibuffer(void);
69 static void		 do_redraw_echoarea(void);
70 static void		 do_redraw_minibuffer(void);
71 static void		 do_redraw_minibuffer_compl(void);
72 static void		 place_cursor(int);
73 static void		 redraw_tab(struct tab*);
74 static void		 update_loading_anim(int, short, void*);
75 static void		 stop_loading_anim(struct tab*);
76 
77 static int		 should_rearrange_windows;
78 static int		 show_tab_bar;
79 static int		 too_small;
80 static int		 x_offset;
81 
82 struct thiskey	 thiskey;
83 struct tab	*current_tab;
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 /* not static so we can see them from help.c */
94 struct buffer		 helpwin;
95 int			 help_lines, help_cols;
96 
97 static WINDOW		*download;
98 /* not static so we can see them from download.c */
99 struct buffer		 downloadwin;
100 int			 download_lines;
101 
102 static int		 side_window;
103 static int		 in_side_window;
104 
105 static struct timeval	loadingev_timer = { 0, 250000 };
106 
107 static char	keybuf[64];
108 
109 /* XXX: don't forget to init these in main() */
110 struct kmap global_map,
111 	minibuffer_map,
112 	*current_map,
113 	*base_map;
114 
115 static inline void
116 update_x_offset(void)
117 {
118 	if (olivetti_mode && fill_column < body_cols)
119 		x_offset = (body_cols - fill_column)/2;
120 	else
121 		x_offset = 0;
122 }
123 
124 void
125 save_excursion(struct excursion *place, struct buffer *buffer)
126 {
127 	place->curs_x = buffer->curs_x;
128 	place->curs_y = buffer->curs_y;
129 	place->line_off = buffer->line_off;
130 	place->top_line = buffer->top_line;
131 	place->current_line = buffer->current_line;
132 	place->cpoff = buffer->cpoff;
133 }
134 
135 void
136 restore_excursion(struct excursion *place, struct buffer *buffer)
137 {
138 	buffer->curs_x = place->curs_x;
139 	buffer->curs_y = place->curs_y;
140 	buffer->line_off = place->line_off;
141 	buffer->top_line = place->top_line;
142 	buffer->current_line = place->current_line;
143 	buffer->cpoff = place->cpoff;
144 }
145 
146 static void
147 restore_curs_x(struct buffer *buffer)
148 {
149 	struct vline	*vl;
150 	const char	*prfx, *text;
151 
152 	vl = buffer->current_line;
153 	if (vl == NULL || vl->line == NULL)
154 		buffer->curs_x = buffer->cpoff = 0;
155 	else if (vl->parent->data != NULL) {
156 		text = vl->parent->data;
157 		buffer->curs_x = utf8_snwidth(text + 1, buffer->cpoff) + 1;
158 	} else
159 		buffer->curs_x = utf8_snwidth(vl->line, buffer->cpoff);
160 
161 	/* small hack: don't olivetti-mode the download pane */
162 	if (buffer != &downloadwin)
163 		buffer->curs_x += x_offset;
164 
165 	if (vl == NULL)
166 		return;
167 
168 	if (vl->parent->data != NULL)
169 		buffer->curs_x += utf8_swidth_between(vl->parent->line,
170 		    vl->parent->data);
171 	else {
172 		prfx = line_prefixes[vl->parent->type].prfx1;
173 		buffer->curs_x += utf8_swidth(prfx);
174 	}
175 }
176 
177 void
178 global_key_unbound(void)
179 {
180 	message("%s is undefined", keybuf);
181 }
182 
183 struct buffer *
184 current_buffer(void)
185 {
186 	if (in_minibuffer)
187 		return &ministate.buffer;
188 	if (in_side_window & SIDE_WINDOW_LEFT)
189 		return &helpwin;
190 	if (in_side_window & SIDE_WINDOW_BOTTOM)
191 		return &downloadwin;
192 	return &current_tab->buffer;
193 }
194 
195 static int
196 readkey(void)
197 {
198 	uint32_t state = 0;
199 
200 	if ((thiskey.key = wgetch(body)) == ERR)
201 		return 0;
202 
203 	thiskey.meta = thiskey.key == 27;
204 	if (thiskey.meta) {
205 		thiskey.key = wgetch(body);
206 		if (thiskey.key == ERR || thiskey.key == 27) {
207 			thiskey.meta = 0;
208 			thiskey.key = 27;
209 		}
210 	}
211 
212 	thiskey.cp = 0;
213 
214 	if ((unsigned int)thiskey.key >= UINT8_MAX)
215 		return 1;
216 
217 	while (1) {
218 		if (!utf8_decode(&state, &thiskey.cp, (uint8_t)thiskey.key))
219 			break;
220 		if ((thiskey.key = wgetch(body)) == ERR) {
221 			message("Error decoding user input");
222 			return 0;
223 		}
224 	}
225 
226 	return 1;
227 }
228 
229 static void
230 dispatch_stdio(int fd, short ev, void *d)
231 {
232 	struct keymap	*k;
233 	const char	*keyname;
234 	char		 tmp[5] = {0};
235 
236 	/* TODO: schedule a redraw? */
237 	if (too_small)
238 		return;
239 
240 	if (!readkey())
241 		return;
242 
243 	if (keybuf[0] != '\0')
244 		strlcat(keybuf, " ", sizeof(keybuf));
245 	if (thiskey.meta)
246 		strlcat(keybuf, "M-", sizeof(keybuf));
247 	if (thiskey.cp != 0) {
248 		utf8_encode(thiskey.cp, tmp);
249 		strlcat(keybuf, tmp, sizeof(keybuf));
250 	} else if ((keyname = unkbd(thiskey.key)) != NULL) {
251 		strlcat(keybuf, keyname, sizeof(keybuf));
252 	} else {
253 		tmp[0] = thiskey.key;
254 		strlcat(keybuf, tmp, sizeof(keybuf));
255 	}
256 
257 	TAILQ_FOREACH(k, &current_map->m, keymaps) {
258 		if (k->meta == thiskey.meta &&
259 		    k->key == thiskey.key) {
260 			if (k->fn == NULL)
261 				current_map = &k->map;
262 			else {
263 				current_map = base_map;
264 				strlcpy(keybuf, "", sizeof(keybuf));
265 				k->fn(current_buffer());
266 			}
267 			goto done;
268 		}
269 	}
270 
271 	if (current_map->unhandled_input != NULL)
272 		current_map->unhandled_input();
273 	else
274 		global_key_unbound();
275 
276 	strlcpy(keybuf, "", sizeof(keybuf));
277 	current_map = base_map;
278 
279 done:
280 	if (side_window & SIDE_WINDOW_LEFT)
281 		recompute_help();
282 
283 	if (should_rearrange_windows)
284 		rearrange_windows();
285 	redraw_tab(current_tab);
286 }
287 
288 static void
289 handle_resize(int sig, short ev, void *d)
290 {
291 	if (event_pending(&resizeev, EV_TIMEOUT, NULL)) {
292 		event_del(&resizeev);
293 	}
294 	evtimer_set(&resizeev, handle_resize_nodelay, NULL);
295 	evtimer_add(&resizeev, &resize_timer);
296 }
297 
298 static void
299 handle_resize_nodelay(int s, short ev, void *d)
300 {
301 	endwin();
302 	refresh();
303 	clear();
304 
305 	rearrange_windows();
306 }
307 
308 static inline int
309 should_show_tab_bar(void)
310 {
311 	if (tab_bar_show == -1)
312 		return 0;
313 	if (tab_bar_show == 0)
314 		return 1;
315 
316 	return TAILQ_NEXT(TAILQ_FIRST(&tabshead), tabs) != NULL;
317 }
318 
319 static void
320 rearrange_windows(void)
321 {
322 	int		 lines;
323 	int		 minibuffer_lines;
324 
325 	should_rearrange_windows = 0;
326 	show_tab_bar = should_show_tab_bar();
327 
328 	lines = LINES;
329 
330 	/* 3 lines for the ui and 12 for the  */
331 	if ((too_small = lines < 15)) {
332 		erase();
333 		printw("Window too small.");
334 		refresh();
335 		return;
336 	}
337 
338 	/* move and resize the windows, in reverse order! */
339 
340 	if (in_minibuffer == MB_COMPREAD) {
341 		minibuffer_lines = MIN(10, lines/2);
342 		mvwin(minibuffer, lines - minibuffer_lines, 0);
343 		wresize(minibuffer, minibuffer_lines, COLS);
344 		lines -= minibuffer_lines;
345 
346 		wrap_page(&ministate.compl.buffer, COLS);
347 	}
348 
349 	mvwin(echoarea, --lines, 0);
350 	wresize(echoarea, 1, COLS);
351 
352 	mvwin(modeline, --lines, 0);
353 	wresize(modeline, 1, COLS);
354 
355 	if (side_window & SIDE_WINDOW_BOTTOM) {
356 		download_lines = MIN(5, lines/2);
357 		mvwin(download, lines - download_lines, 0);
358 		wresize(download, download_lines, COLS);
359 		lines -= download_lines;
360 
361 		wrap_page(&downloadwin, COLS);
362 	}
363 
364 	body_lines = show_tab_bar ? --lines : lines;
365 	body_cols = COLS;
366 
367 	/*
368 	 * Here we make the assumption that show_tab_bar is either 0
369 	 * or 1, and reuse that as argument to mvwin.
370 	 */
371 	if (side_window & SIDE_WINDOW_LEFT) {
372 		help_cols = 0.3 * COLS;
373 		help_lines = lines;
374 		mvwin(help, show_tab_bar, 0);
375 		wresize(help, help_lines, help_cols);
376 
377 		wrap_page(&helpwin, help_cols);
378 
379 		body_cols = COLS - help_cols - 1;
380 		mvwin(body, show_tab_bar, help_cols);
381 	} else
382 		mvwin(body, show_tab_bar, 0);
383 
384 	update_x_offset();
385 	wresize(body, body_lines, body_cols);
386 
387 	if (show_tab_bar)
388 		wresize(tabline, 1, COLS);
389 
390 	wrap_page(&current_tab->buffer, body_cols);
391 	redraw_tab(current_tab);
392 }
393 
394 static void
395 line_prefix_and_text(struct vline *vl, char *buf, size_t len,
396     const char **prfx_ret, const char **text_ret)
397 {
398 	int type, i, cont, width;
399 	char *space, *t;
400 
401 	if ((*text_ret = vl->line) == NULL)
402 		*text_ret = "";
403 
404 	cont = vl->flags & L_CONTINUATION;
405 	type = vl->parent->type;
406 	if (!cont)
407 		*prfx_ret = line_prefixes[type].prfx1;
408 	else
409 		*prfx_ret = line_prefixes[type].prfx2;
410 
411 	space = vl->parent->data;
412 	if (!emojify_link || type != LINE_LINK || space == NULL)
413 		return;
414 
415 	if (cont) {
416 		memset(buf, 0, len);
417 		width = utf8_swidth_between(vl->parent->line, space);
418 		for (i = 0; i < width + 1; ++i)
419 			strlcat(buf, " ", len);
420 	} else {
421 		strlcpy(buf, *text_ret, len);
422 		if ((t = strchr(buf, ' ')) != NULL)
423 			*t = '\0';
424 		strlcat(buf, " ", len);
425 
426 		/* skip the emoji */
427 		*text_ret += (space - vl->parent->line) + 1;
428 	}
429 
430 	*prfx_ret = buf;
431 }
432 
433 static inline void
434 print_vline_descr(int width, WINDOW *window, struct vline *vl)
435 {
436 	int x, y, goal;
437 
438 	switch (vl->parent->type) {
439 	case LINE_COMPL:
440 	case LINE_COMPL_CURRENT:
441 		goal = width/2;
442 		break;
443 	case LINE_DOWNLOAD:
444 	case LINE_DOWNLOAD_DONE:
445 		goal = width/4;
446 		break;
447 	case LINE_HELP:
448 		goal = 8;
449 		break;
450 	default:
451 		return;
452 	}
453 
454 	if (vl->parent->alt == NULL)
455 		return;
456 
457 	(void)y;
458 	getyx(window, y, x);
459 
460 	if (goal <= x)
461 		wprintw(window, " ");
462 	for (; goal > x; ++x)
463 		wprintw(window, " ");
464 
465 	wprintw(window, "%s", vl->parent->alt);
466 }
467 
468 /*
469  * Core part of the rendering.  It prints a vline starting from the
470  * current cursor position.  Printing a vline consists of skipping
471  * `off' columns (for olivetti-mode), print the correct prefix (which
472  * may be the emoji in case of emojified links-lines), printing the
473  * text itself, filling until width - off and filling off columns
474  * again.
475  */
476 static void
477 print_vline(int off, int width, WINDOW *window, struct vline *vl)
478 {
479 	/*
480 	 * Believe me or not, I've seen emoji ten code points long!
481 	 * That means, to stay large, 4*10 bytes + NUL.
482 	 */
483 	char emojibuf[41] = {0};
484 	const char *text, *prfx;
485 	struct line_face *f;
486 	int i, left, x, y;
487 
488 	f = &line_faces[vl->parent->type];
489 
490 	/* unused, set by getyx */
491 	(void)y;
492 
493 	line_prefix_and_text(vl, emojibuf, sizeof(emojibuf), &prfx, &text);
494 
495 	wattr_on(window, body_face.left, NULL);
496 	for (i = 0; i < off; i++)
497 		waddch(window, ' ');
498 	wattr_off(window, body_face.left, NULL);
499 
500 	wattr_on(window, f->prefix, NULL);
501 	wprintw(window, "%s", prfx);
502 	wattr_off(window, f->prefix, NULL);
503 
504 	wattr_on(window, f->text, NULL);
505 	wprintw(window, "%s", text);
506 	print_vline_descr(width, window, vl);
507 	wattr_off(window, f->text, NULL);
508 
509 	getyx(window, y, x);
510 
511 	left = width - x;
512 
513 	wattr_on(window, f->trail, NULL);
514 	for (i = 0; i < left - off; ++i)
515 		waddch(window, ' ');
516 	wattr_off(window, f->trail, NULL);
517 
518 	wattr_on(window, body_face.right, NULL);
519 	for (i = 0; i < off; i++)
520 		waddch(window, ' ');
521 	wattr_off(window, body_face.right, NULL);
522 
523 }
524 
525 static void
526 redraw_tabline(void)
527 {
528 	struct tab	*tab;
529 	size_t		 toskip, ots, tabwidth, space, x;
530 	int		 current, y, truncated, pair;
531 	const char	*title;
532 	char		 buf[25];
533 
534 	x = 0;
535 
536 	/* unused, but setted by a getyx */
537 	(void)y;
538 
539 	tabwidth = sizeof(buf)+1;
540 	space = COLS-2;
541 
542 	toskip = 0;
543 	TAILQ_FOREACH(tab, &tabshead, tabs) {
544 		toskip++;
545 		if (tab == current_tab)
546 			break;
547 	}
548 
549 	if (toskip * tabwidth < space)
550 		toskip = 0;
551 	else {
552 		ots = toskip;
553 		toskip--;
554 		while (toskip != 0 &&
555 		    (ots - toskip+1) * tabwidth < space)
556 			toskip--;
557 	}
558 
559 	werase(tabline);
560 	wattr_on(tabline, tab_face.background, NULL);
561 	wprintw(tabline, toskip == 0 ? " " : "<");
562 	wattr_off(tabline, tab_face.background, NULL);
563 
564 	truncated = 0;
565 	TAILQ_FOREACH(tab, &tabshead, tabs) {
566 		if (truncated)
567 			break;
568 		if (toskip != 0) {
569 			toskip--;
570 			continue;
571 		}
572 
573 		getyx(tabline, y, x);
574 		if (x + sizeof(buf)+2 >= (size_t)COLS)
575 			truncated = 1;
576 
577 		current = tab == current_tab;
578 
579 		if (*(title = tab->buffer.page.title) == '\0')
580 			title = tab->hist_cur->h;
581 
582 		if (tab->flags & TAB_URGENT)
583 			strlcpy(buf, "!", sizeof(buf));
584 		else
585 			strlcpy(buf, " ", sizeof(buf));
586 
587 		if (strlcat(buf, title, sizeof(buf)) >= sizeof(buf)) {
588 			/* truncation happens */
589 			strlcpy(&buf[sizeof(buf)-4], "...", 4);
590 		} else {
591 			/* pad with spaces */
592 			while (strlcat(buf, "    ", sizeof(buf)) < sizeof(buf))
593 				/* nop */ ;
594 		}
595 
596 		pair = current ? tab_face.current : tab_face.tab;
597 		wattr_on(tabline, pair, NULL);
598 		wprintw(tabline, "%s", buf);
599 		wattr_off(tabline, pair, NULL);
600 
601 		wattr_on(tabline, tab_face.background, NULL);
602 		if (TAILQ_NEXT(tab, tabs) != NULL)
603 			wprintw(tabline, "┃");
604 		wattr_off(tabline, tab_face.background, NULL);
605 	}
606 
607 	wattr_on(tabline, tab_face.background, NULL);
608 	for (; x < (size_t)COLS; ++x)
609 		waddch(tabline, ' ');
610 	if (truncated)
611 		mvwprintw(tabline, 0, COLS-1, ">");
612 	wattr_off(tabline, tab_face.background, NULL);
613 }
614 
615 /*
616  * Compute the first visible line around vl.  Try to search forward
617  * until the end of the buffer; if a visible line is not found, search
618  * backward.  Return NULL if no viable line was found.
619  */
620 struct vline *
621 adjust_line(struct vline *vl, struct buffer *buffer)
622 {
623 	struct vline *t;
624 
625 	if (vl == NULL)
626 		return NULL;
627 
628 	if (!(vl->parent->flags & L_HIDDEN))
629 		return vl;
630 
631 	/* search forward */
632 	for (t = vl;
633 	     t != NULL && t->parent->flags & L_HIDDEN;
634 	     t = TAILQ_NEXT(t, vlines))
635 		;		/* nop */
636 
637 	if (t != NULL)
638 		return t;
639 
640 	/* search backward */
641 	for (t = vl;
642 	     t != NULL && t->parent->flags & L_HIDDEN;
643 	     t = TAILQ_PREV(t, vhead, vlines))
644 		;		/* nop */
645 
646 	return t;
647 }
648 
649 static void
650 redraw_window(WINDOW *win, int off, int height, int width,
651     struct buffer *buffer)
652 {
653 	struct vline	*vl;
654 	int		 l, onscreen;
655 
656 	restore_curs_x(buffer);
657 
658 	/*
659 	 * TODO: ignoring buffer->force_update and always
660 	 * re-rendering.  In theory we can recompute the y position
661 	 * without a re-render, and optimize here.  It's not the only
662 	 * optimisation possible here, wscrl wolud also be an
663 	 * interesting one.
664 	 */
665 
666 again:
667 	werase(win);
668 	buffer->curs_y = 0;
669 
670 	if (TAILQ_EMPTY(&buffer->head))
671 		goto end;
672 
673 	if (buffer->top_line == NULL)
674 		buffer->top_line = TAILQ_FIRST(&buffer->head);
675 
676 	buffer->top_line = adjust_line(buffer->top_line, buffer);
677 	if (buffer->top_line == NULL)
678 		goto end;
679 
680 	buffer->current_line = adjust_line(buffer->current_line, buffer);
681 
682 	l = 0;
683 	onscreen = 0;
684 	for (vl = buffer->top_line; vl != NULL; vl = TAILQ_NEXT(vl, vlines)) {
685 		if (vl->parent->flags & L_HIDDEN)
686 			continue;
687 
688 		wmove(win, l, 0);
689 		print_vline(off, width, win, vl);
690 
691 		if (vl == buffer->current_line)
692 			onscreen = 1;
693 
694 		if (!onscreen)
695 			buffer->curs_y++;
696 
697 		l++;
698 		if (l == height)
699 			break;
700 	}
701 
702 	if (!onscreen) {
703 		for (; vl != NULL; vl = TAILQ_NEXT(vl, vlines)) {
704 			if (vl == buffer->current_line)
705 				break;
706 			if (vl->parent->flags & L_HIDDEN)
707 				continue;
708 			buffer->line_off++;
709 			buffer->top_line = TAILQ_NEXT(buffer->top_line, vlines);
710 		}
711 
712 		if (vl != NULL)
713 			goto again;
714 	}
715 
716 	buffer->last_line_off = buffer->line_off;
717 	buffer->force_redraw = 0;
718 end:
719 	wmove(win, buffer->curs_y, buffer->curs_x);
720 }
721 
722 static void
723 redraw_download(void)
724 {
725 	redraw_window(download, 0, download_lines, COLS, &downloadwin);
726 }
727 
728 static void
729 redraw_help(void)
730 {
731 	redraw_window(help, 0, help_lines, help_cols, &helpwin);
732 }
733 
734 static void
735 redraw_body(struct tab *tab)
736 {
737 	static struct tab *last_tab;
738 
739 	if (last_tab != tab)
740 		tab->buffer.force_redraw =1;
741 	last_tab = tab;
742 
743 	redraw_window(body, x_offset, body_lines, body_cols, &tab->buffer);
744 }
745 
746 static inline char
747 trust_status_char(enum trust_state ts)
748 {
749 	switch (ts) {
750 	case TS_UNKNOWN:	return '-';
751 	case TS_UNTRUSTED:	return '!';
752 	case TS_TEMP_TRUSTED:	return '!';
753 	case TS_TRUSTED:	return 'v';
754 	case TS_VERIFIED:	return 'V';
755 	default:		return 'X';
756 	}
757 }
758 
759 static void
760 redraw_modeline(struct tab *tab)
761 {
762 	struct buffer	*buffer;
763 	double		 pct;
764 	int		 x, y, max_x, max_y;
765 	const char	*mode;
766 	const char	*spin = "-\\|/";
767 
768 	buffer = current_buffer();
769 	mode = buffer->page.name;
770 
771 	werase(modeline);
772 	wattr_on(modeline, modeline_face.background, NULL);
773 	wmove(modeline, 0, 0);
774 
775 	wprintw(modeline, "-%c%c %s ",
776 	    spin[tab->loading_anim_step],
777 	    trust_status_char(tab->trust),
778 	    mode == NULL ? "(none)" : mode);
779 
780 	pct = (buffer->line_off + buffer->curs_y) * 100.0
781 		/ buffer->line_max;
782 
783 	if (buffer->line_max <= (size_t)body_lines)
784 		wprintw(modeline, "All ");
785 	else if (buffer->line_off == 0)
786 		wprintw(modeline, "Top ");
787 	else if (buffer->line_off + body_lines >= buffer->line_max)
788 		wprintw(modeline, "Bottom ");
789 	else
790 		wprintw(modeline, "%.0f%% ", pct);
791 
792 	wprintw(modeline, "%d/%d %s ",
793 	    buffer->line_off + buffer->curs_y,
794 	    buffer->line_max,
795 	    tab->hist_cur->h);
796 
797 	getyx(modeline, y, x);
798 	getmaxyx(modeline, max_y, max_x);
799 
800 	(void)y;
801 	(void)max_y;
802 
803 	for (; x < max_x; ++x)
804 		waddstr(modeline, "-");
805 
806 	wattr_off(modeline, modeline_face.background, NULL);
807 }
808 
809 static void
810 redraw_minibuffer(void)
811 {
812 	wattr_on(echoarea, minibuffer_face.background, NULL);
813 	werase(echoarea);
814 
815 	if (in_minibuffer)
816 		do_redraw_minibuffer();
817 	else
818 		do_redraw_echoarea();
819 
820 	if (in_minibuffer == MB_COMPREAD)
821 		do_redraw_minibuffer_compl();
822 
823 	wattr_off(echoarea, minibuffer_face.background, NULL);
824 }
825 
826 static void
827 do_redraw_echoarea(void)
828 {
829 	struct vline *vl;
830 
831 	if (ministate.curmesg != NULL)
832 		wprintw(echoarea, "%s", ministate.curmesg);
833 	else if (*keybuf != '\0')
834 		waddstr(echoarea, keybuf);
835 	else {
836 		/* If nothing else, show the URL at point */
837 		vl = current_tab->buffer.current_line;
838 		if (vl != NULL && vl->parent->type == LINE_LINK)
839 			waddstr(echoarea, vl->parent->alt);
840 	}
841 }
842 
843 static void
844 do_redraw_minibuffer(void)
845 {
846 	struct buffer	*cmplbuf, *buffer;
847 	size_t		 off_y, off_x = 0;
848 	const char	*start, *c;
849 
850 	cmplbuf = &ministate.compl.buffer;
851 	buffer = &ministate.buffer;
852 	(void)off_y;		/* unused, set by getyx */
853 
854 	wmove(echoarea, 0, 0);
855 
856 	if (in_minibuffer == MB_COMPREAD)
857 		wprintw(echoarea, "(%2d) ",
858 		    cmplbuf->line_max);
859 
860 	wprintw(echoarea, "%s", ministate.prompt);
861 	if (ministate.hist_cur != NULL)
862 		wprintw(echoarea, "(%zu/%zu) ",
863 		    ministate.hist_off + 1,
864 		    ministate.history->len);
865 
866 	getyx(echoarea, off_y, off_x);
867 
868 	start = ministate.hist_cur != NULL
869 		? ministate.hist_cur->h
870 		: ministate.buf;
871 	c = utf8_nth(buffer->current_line->line, buffer->cpoff);
872 	while (utf8_swidth_between(start, c) > (size_t)COLS/2) {
873 		start = utf8_next_cp(start);
874 	}
875 
876 	waddstr(echoarea, start);
877 
878 	if (ministate.curmesg != NULL)
879 		wprintw(echoarea, " [%s]", ministate.curmesg);
880 
881 	wmove(echoarea, 0, off_x + utf8_swidth_between(start, c));
882 }
883 
884 static void
885 do_redraw_minibuffer_compl(void)
886 {
887 	redraw_window(minibuffer, 0, 10, COLS,
888 	    &ministate.compl.buffer);
889 }
890 
891 /*
892  * Place the cursor in the right ncurses window.  If soft is 1, use
893  * wnoutrefresh (which shouldn't cause any I/O); otherwise use
894  * wrefresh.
895  */
896 static void
897 place_cursor(int soft)
898 {
899 	int (*touch)(WINDOW *);
900 
901 	if (soft)
902 		touch = wnoutrefresh;
903 	else
904 		touch = wrefresh;
905 
906 	if (in_minibuffer) {
907 		if (side_window & SIDE_WINDOW_LEFT)
908 			touch(help);
909 		if (side_window & SIDE_WINDOW_BOTTOM)
910 			touch(download);
911 		touch(body);
912 		touch(echoarea);
913 	} else if (in_side_window & SIDE_WINDOW_LEFT) {
914 		touch(body);
915 		touch(echoarea);
916                 if (in_side_window & SIDE_WINDOW_BOTTOM)
917 			touch(download);
918 		touch(help);
919 	} else if (in_side_window & SIDE_WINDOW_BOTTOM) {
920 		touch(body);
921 		touch(echoarea);
922 		if (in_side_window & SIDE_WINDOW_LEFT)
923 			touch(help);
924 		touch(download);
925 	} else {
926 		if (side_window & SIDE_WINDOW_LEFT)
927 			touch(help);
928 		if (side_window & SIDE_WINDOW_BOTTOM)
929 			touch(download);
930 		touch(echoarea);
931 		touch(body);
932 	}
933 }
934 
935 static void
936 redraw_tab(struct tab *tab)
937 {
938 	if (too_small)
939 		return;
940 
941 	if (side_window & SIDE_WINDOW_LEFT) {
942 		redraw_help();
943 		wnoutrefresh(help);
944 	}
945 
946 	if (side_window & SIDE_WINDOW_BOTTOM) {
947 		redraw_download();
948 		wnoutrefresh(download);
949 	}
950 
951 	if (show_tab_bar)
952 		redraw_tabline();
953 
954 	redraw_body(tab);
955 	redraw_modeline(tab);
956 	redraw_minibuffer();
957 
958 	wnoutrefresh(tabline);
959 	wnoutrefresh(modeline);
960 
961 	if (in_minibuffer == MB_COMPREAD)
962 		wnoutrefresh(minibuffer);
963 
964 	place_cursor(1);
965 
966 	doupdate();
967 
968 	if (set_title)
969 		dprintf(1, "\033]2;%s - Telescope\a",
970 		    current_tab->buffer.page.title);
971 }
972 
973 void
974 start_loading_anim(struct tab *tab)
975 {
976 	if (tab->loading_anim)
977 		return;
978 	tab->loading_anim = 1;
979 	evtimer_set(&tab->loadingev, update_loading_anim, tab);
980 	evtimer_add(&tab->loadingev, &loadingev_timer);
981 }
982 
983 static void
984 update_loading_anim(int fd, short ev, void *d)
985 {
986 	struct tab	*tab = d;
987 
988 	tab->loading_anim_step = (tab->loading_anim_step+1)%4;
989 
990 	if (tab == current_tab) {
991 		redraw_modeline(tab);
992 		wrefresh(modeline);
993 		wrefresh(body);
994 		if (in_minibuffer)
995 			wrefresh(echoarea);
996 	}
997 
998 	evtimer_add(&tab->loadingev, &loadingev_timer);
999 }
1000 
1001 static void
1002 stop_loading_anim(struct tab *tab)
1003 {
1004 	if (!tab->loading_anim)
1005 		return;
1006 	evtimer_del(&tab->loadingev);
1007 	tab->loading_anim = 0;
1008 	tab->loading_anim_step = 0;
1009 
1010 	if (tab != current_tab)
1011 		return;
1012 
1013 	redraw_modeline(tab);
1014 
1015 	wrefresh(modeline);
1016 	wrefresh(body);
1017 	if (in_minibuffer)
1018 		wrefresh(echoarea);
1019 }
1020 
1021 int
1022 ui_print_colors(void)
1023 {
1024 	int colors = 0, pairs = 0, can_change = 0;
1025 	int columns = 16, lines, color, i, j;
1026 
1027 	initscr();
1028 	if (has_colors()) {
1029 		start_color();
1030 		use_default_colors();
1031 
1032 		colors = COLORS;
1033 		pairs = COLOR_PAIRS;
1034 		can_change = can_change_color();
1035 	}
1036 	endwin();
1037 
1038 	printf("Term info:\n");
1039 	printf("TERM=%s COLORS=%d COLOR_PAIRS=%d can_change_colors=%d\n",
1040 	    getenv("TERM"), colors, pairs, can_change);
1041 	printf("\n");
1042 
1043 	if (colors == 0) {
1044 		printf("No color support\n");
1045 		return 0;
1046 	}
1047 
1048 	printf("Available colors:\n\n");
1049 	lines = (colors - 1) / columns + 1;
1050 	color = 0;
1051 	for (i = 0; i < lines; ++i) {
1052 		for (j = 0; j < columns; ++j, ++color) {
1053 			printf("\033[0;38;5;%dm %03d", color, color);
1054 		}
1055 		printf("\n");
1056 	}
1057 
1058 	printf("\033[0m");
1059 	fflush(stdout);
1060 	return 0;
1061 }
1062 
1063 int
1064 ui_init()
1065 {
1066 	setlocale(LC_ALL, "");
1067 
1068 	if (TAILQ_EMPTY(&global_map.m)) {
1069 		fprintf(stderr, "no keys defined!\n");
1070 		return 0;
1071 	}
1072 
1073 	minibuffer_init();
1074 
1075 	/* initialize download window */
1076 	TAILQ_INIT(&downloadwin.head);
1077 	TAILQ_INIT(&downloadwin.page.head);
1078 
1079 	/* initialize help window */
1080 	TAILQ_INIT(&helpwin.head);
1081 	TAILQ_INIT(&helpwin.page.head);
1082 
1083 	base_map = &global_map;
1084 	current_map = &global_map;
1085 
1086 	initscr();
1087 
1088 	if (enable_colors) {
1089 		if (has_colors()) {
1090 			start_color();
1091 			use_default_colors();
1092 		} else
1093 			enable_colors = 0;
1094 	}
1095 
1096 	config_apply_style();
1097 
1098 	raw();
1099 	noecho();
1100 	nonl();
1101 	intrflush(stdscr, FALSE);
1102 
1103 	if ((tabline = newwin(1, 1, 0, 0)) == NULL)
1104 		return 0;
1105 	if ((body = newwin(1, 1, 0, 0)) == NULL)
1106 		return 0;
1107 	if ((modeline = newwin(1, 1, 0, 0)) == NULL)
1108 		return 0;
1109 	if ((echoarea = newwin(1, 1, 0, 0)) == NULL)
1110 		return 0;
1111 	if ((minibuffer = newwin(1, 1, 0, 0)) == NULL)
1112 		return 0;
1113 	if ((download = newwin(1, 1, 0, 0)) == NULL)
1114 		return 0;
1115 	if ((help = newwin(1, 1, 0, 0)) == NULL)
1116 		return 0;
1117 
1118 	wbkgd(body, body_face.body);
1119 	wbkgd(download, download_face.background);
1120 	wbkgd(echoarea, minibuffer_face.background);
1121 
1122 	update_x_offset();
1123 
1124 	keypad(body, TRUE);
1125 	scrollok(body, FALSE);
1126 
1127 	/* non-blocking input */
1128 	wtimeout(body, 0);
1129 	wtimeout(help, 0);
1130 
1131 	mvwprintw(body, 0, 0, "");
1132 
1133 	evtimer_set(&resizeev, handle_resize, NULL);
1134 
1135 	event_set(&stdioev, 0, EV_READ | EV_PERSIST, dispatch_stdio, NULL);
1136 	event_add(&stdioev, NULL);
1137 
1138 	signal_set(&winchev, SIGWINCH, handle_resize, NULL);
1139 	signal_add(&winchev, NULL);
1140 
1141 	return 1;
1142 }
1143 
1144 void
1145 ui_main_loop(void)
1146 {
1147 	switch_to_tab(current_tab);
1148 	rearrange_windows();
1149 
1150 	event_dispatch();
1151 }
1152 
1153 void
1154 ui_on_tab_loaded(struct tab *tab)
1155 {
1156 	stop_loading_anim(tab);
1157 	message("Loaded %s", tab->hist_cur->h);
1158 
1159 	if (show_tab_bar)
1160 		redraw_tabline();
1161 
1162 	wrefresh(tabline);
1163 	place_cursor(0);
1164 }
1165 
1166 void
1167 ui_on_tab_refresh(struct tab *tab)
1168 {
1169 	wrap_page(&tab->buffer, body_cols);
1170 	if (tab == current_tab)
1171 		redraw_tab(tab);
1172 	else
1173 		tab->flags |= TAB_URGENT;
1174 }
1175 
1176 void
1177 ui_on_download_refresh(void)
1178 {
1179 	if (side_window & SIDE_WINDOW_BOTTOM) {
1180                 recompute_downloads();
1181 		redraw_tab(current_tab);
1182 	}
1183 }
1184 
1185 const char *
1186 ui_keyname(int k)
1187 {
1188 	return keyname(k);
1189 }
1190 
1191 void
1192 ui_toggle_side_window(int kind)
1193 {
1194 	if (in_side_window & kind)
1195 		ui_other_window();
1196 
1197 	side_window ^= kind;
1198 	if (side_window & SIDE_WINDOW_LEFT)
1199 		recompute_help();
1200 	if (side_window & SIDE_WINDOW_BOTTOM)
1201 		recompute_downloads();
1202 
1203 	/*
1204 	 * ugly hack, but otherwise the window doesn't get updated
1205 	 * until I call rearrange_windows a second time (e.g. via
1206 	 * C-l).  I will be happy to know why something like this is
1207 	 * needed.
1208 	 */
1209 	rearrange_windows();
1210 	rearrange_windows();
1211 }
1212 
1213 void
1214 ui_show_downloads_pane(void)
1215 {
1216 	if (!(side_window & SIDE_WINDOW_BOTTOM))
1217 		ui_toggle_side_window(SIDE_WINDOW_BOTTOM);
1218 }
1219 
1220 void
1221 ui_schedule_redraw(void)
1222 {
1223 	should_rearrange_windows = 1;
1224 }
1225 
1226 void
1227 ui_require_input(struct tab *tab, int hide, int proto)
1228 {
1229 	void (*fn)(void);
1230 
1231 	if (proto == PROTO_GEMINI)
1232 		fn = ir_select_gemini;
1233 	else if (proto == PROTO_GOPHER)
1234 		fn = ir_select_gopher;
1235 	else
1236 		abort();
1237 
1238 	/* TODO: hard-switching to another tab is ugly */
1239 	switch_to_tab(tab);
1240 
1241 	enter_minibuffer(sensible_self_insert, fn, exit_minibuffer,
1242 	    &ir_history, NULL, NULL);
1243 	strlcpy(ministate.prompt, "Input required: ",
1244 	    sizeof(ministate.prompt));
1245 	redraw_tab(tab);
1246 }
1247 
1248 void
1249 ui_after_message_hook(void)
1250 {
1251 	redraw_minibuffer();
1252 	place_cursor(0);
1253 }
1254 
1255 void
1256 ui_yornp(const char *prompt, void (*fn)(int, struct tab *),
1257     struct tab *data)
1258 {
1259 	yornp(prompt, fn, data);
1260 	redraw_tab(current_tab);
1261 }
1262 
1263 void
1264 ui_read(const char *prompt, void (*fn)(const char*, struct tab *),
1265     struct tab *data, const char *input)
1266 {
1267 	minibuffer_read(prompt, fn, data);
1268 
1269 	if (input != NULL) {
1270 		strlcpy(ministate.buf, input, sizeof(ministate.buf));
1271 		cmd_move_end_of_line(&ministate.buffer);
1272 	}
1273 
1274 	redraw_tab(current_tab);
1275 }
1276 
1277 void
1278 ui_other_window(void)
1279 {
1280 	if (in_side_window & SIDE_WINDOW_LEFT &&
1281 	    side_window & SIDE_WINDOW_BOTTOM)
1282 		in_side_window = SIDE_WINDOW_BOTTOM;
1283 	else if (in_side_window)
1284 		in_side_window = 0;
1285 	else if (!in_side_window && side_window & SIDE_WINDOW_LEFT)
1286 		in_side_window = SIDE_WINDOW_LEFT;
1287 	else if (!in_side_window && side_window)
1288 		in_side_window = SIDE_WINDOW_BOTTOM;
1289 	else
1290 		message("No other window to select");
1291 }
1292 
1293 void
1294 ui_suspend(void)
1295 {
1296 	endwin();
1297 
1298 	kill(getpid(), SIGSTOP);
1299 
1300 	refresh();
1301 	clear();
1302 	rearrange_windows();
1303 }
1304 
1305 void
1306 ui_end(void)
1307 {
1308 	endwin();
1309 }