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  * This way is easy to scroll: just call wscrl and then render the
27  * first/last line!
28  *
29  * This means that on every resize we have to clear our list of lines
30  * and re-render everything.  A clever approach would be to do this
31  * ``on-demand'', but it's still missing.
32  *
33  */
34 
35 #include "telescope.h"
36 #include "cmd.gen.h"
37 
38 #include <assert.h>
39 #include <curses.h>
40 #include <event.h>
41 #include <limits.h>
42 #include <locale.h>
43 #include <signal.h>
44 #include <stdarg.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <unistd.h>
48 
49 #define TAB_CURRENT	0x1
50 #define TAB_URGENT	0x2
51 
52 #define NEW_TAB_URL	"about:new"
53 
54 static struct event	stdioev, winchev;
55 
56 static void		 load_default_keys(void);
57 static void		 restore_cursor(struct buffer*);
58 
59 static void		 global_key_unbound(void);
60 static void		 minibuffer_hist_save_entry(void);
61 static void		 minibuffer_taint_hist(void);
62 static void		 minibuffer_self_insert(void);
63 static void		 eecmd_self_insert(void);
64 static void		 eecmd_select(void);
65 static void		 ir_self_insert(void);
66 static void		 ir_select(void);
67 static void		 lu_self_insert(void);
68 static void		 lu_select(void);
69 static void		 bp_select(void);
70 static void		 yornp_self_insert(void);
71 static void		 yornp_abort(void);
72 static void		 read_self_insert(void);
73 static void		 read_abort(void);
74 static void		 read_select(void);
75 
76 static struct vline	*nth_line(struct buffer*, size_t);
77 static struct tab	*current_tab(void);
78 static struct buffer	*current_buffer(void);
79 static int		 readkey(void);
80 static void		 dispatch_stdio(int, short, void*);
81 static void		 handle_clear_minibuf(int, short, void*);
82 static void		 handle_resize(int, short, void*);
83 static void		 handle_resize_nodelay(int, short, void*);
84 static int		 wrap_page(struct buffer*, int);
85 static void		 print_vline(WINDOW*, struct vline*);
86 static void		 redraw_tabline(void);
87 static void		 redraw_window(WINDOW*, int, struct buffer*);
88 static void		 redraw_help(void);
89 static void		 redraw_body(struct tab*);
90 static void		 redraw_modeline(struct tab*);
91 static void		 redraw_minibuffer(void);
92 static void		 redraw_tab(struct tab*);
93 static void		 emit_help_item(char*, void*);
94 static void		 rec_compute_help(struct kmap*, char*, size_t);
95 static void		 recompute_help(void);
96 static void		 vmessage(const char*, va_list);
97 static void		 message(const char*, ...) __attribute__((format(printf, 1, 2)));
98 static void		 start_loading_anim(struct tab*);
99 static void		 update_loading_anim(int, short, void*);
100 static void		 stop_loading_anim(struct tab*);
101 static void		 load_url_in_tab(struct tab*, const char*);
102 static void		 enter_minibuffer(void(*)(void), void(*)(void), void(*)(void), struct histhead*);
103 static void		 exit_minibuffer(void);
104 static void		 switch_to_tab(struct tab*);
105 static struct tab	*new_tab(const char*);
106 static void		 session_new_tab_cb(const char*);
107 static void		 usage(void);
108 
109 static int		 x_offset;
110 
111 static struct { short meta; int key; uint32_t cp; } thiskey;
112 
113 static struct event	resizeev;
114 static struct timeval	resize_timer = { 0, 250000 };
115 
116 static WINDOW	*tabline, *body, *modeline, *minibuf;
117 static int	 body_lines, body_cols;
118 
119 static WINDOW		*help;
120 static struct buffer	 helpwin;
121 static int		 help_lines, help_cols;
122 
123 static int		 side_window;
124 
125 static struct event	clminibufev;
126 static struct timeval	clminibufev_timer = { 5, 0 };
127 static struct timeval	loadingev_timer = { 0, 250000 };
128 
129 static uint32_t		 tab_counter;
130 
131 static char	keybuf[64];
132 
133 static void (*yornp_cb)(int, unsigned int);
134 static unsigned int yornp_data;
135 
136 static void (*read_cb)(const char*, unsigned int);
137 static unsigned int read_data;
138 
139 struct kmap global_map,
140 	minibuffer_map,
141 	*current_map,
142 	*base_map;
143 
144 static struct histhead eecmd_history,
145 	ir_history,
146 	lu_history,
147 	read_history;
148 
149 static int	in_minibuffer;
150 
151 static struct {
152 	char		*curmesg;
153 
154 	char		 prompt[64];
155 	void		 (*donefn)(void);
156 	void		 (*abortfn)(void);
157 
158 	char		 buf[1025];
159 	struct line	 line;
160 	struct vline	 vline;
161 	struct buffer	 buffer;
162 
163 	struct histhead	*history;
164 	struct hist	*hist_cur;
165 	size_t		 hist_off;
166 } ministate;
167 
168 static inline void
169 update_x_offset()
170 {
171 	if (olivetti_mode && fill_column < body_cols)
172 		x_offset = (body_cols - fill_column)/2;
173 	else
174 		x_offset = 0;
175 }
176 
177 static inline void
178 global_set_key(const char *key, void (*fn)(struct buffer*))
179 {
180 	if (!kmap_define_key(&global_map, key, fn))
181 		_exit(1);
182 }
183 
184 static inline void
185 minibuffer_set_key(const char *key, void (*fn)(struct buffer*))
186 {
187 	if (!kmap_define_key(&minibuffer_map, key, fn))
188 		_exit(1);
189 }
190 
191 static void
192 load_default_keys(void)
193 {
194 	/* === global map === */
195 
196 	/* emacs */
197 	global_set_key("C-p",		cmd_previous_line);
198 	global_set_key("C-n",		cmd_next_line);
199 	global_set_key("C-f",		cmd_forward_char);
200 	global_set_key("C-b",		cmd_backward_char);
201 	global_set_key("M-{",		cmd_backward_paragraph);
202 	global_set_key("M-}",		cmd_forward_paragraph);
203 	global_set_key("C-a",		cmd_move_beginning_of_line);
204 	global_set_key("C-e",		cmd_move_end_of_line);
205 
206 	global_set_key("M-v",		cmd_scroll_up);
207 	global_set_key("C-v",		cmd_scroll_down);
208 	global_set_key("M-space",	cmd_scroll_up);
209 	global_set_key("space",		cmd_scroll_down);
210 
211 	global_set_key("M-<",		cmd_beginning_of_buffer);
212 	global_set_key("M->",		cmd_end_of_buffer);
213 
214 	global_set_key("C-x C-c",	cmd_kill_telescope);
215 
216 	global_set_key("C-g",		cmd_clear_minibuf);
217 
218 	global_set_key("M-x",		cmd_execute_extended_command);
219 	global_set_key("C-x C-f",	cmd_load_url);
220 	global_set_key("C-x M-f",	cmd_load_current_url);
221 
222 	global_set_key("C-x t 0",	cmd_tab_close);
223 	global_set_key("C-x t 1",	cmd_tab_close_other);
224 	global_set_key("C-x t 2",	cmd_tab_new);
225 	global_set_key("C-x t o",	cmd_tab_next);
226 	global_set_key("C-x t O",	cmd_tab_previous);
227 	global_set_key("C-x t m",	cmd_tab_move);
228 	global_set_key("C-x t M",	cmd_tab_move_to);
229 
230 	global_set_key("C-M-b",		cmd_previous_page);
231 	global_set_key("C-M-f",		cmd_next_page);
232 
233 	global_set_key("<f7> a",	cmd_bookmark_page);
234 	global_set_key("<f7> <f7>",	cmd_list_bookmarks);
235 
236 	/* vi/vi-like */
237 	global_set_key("k",		cmd_previous_line);
238 	global_set_key("j",		cmd_next_line);
239 	global_set_key("l",		cmd_forward_char);
240 	global_set_key("h",		cmd_backward_char);
241 	global_set_key("{",		cmd_backward_paragraph);
242 	global_set_key("}",		cmd_forward_paragraph);
243 	global_set_key("^",		cmd_move_beginning_of_line);
244 	global_set_key("$",		cmd_move_end_of_line);
245 
246 	global_set_key("K",		cmd_scroll_line_up);
247 	global_set_key("J",		cmd_scroll_line_down);
248 
249 	global_set_key("g g",		cmd_beginning_of_buffer);
250 	global_set_key("G",		cmd_end_of_buffer);
251 
252 	global_set_key("g D",		cmd_tab_close);
253 	global_set_key("g N",		cmd_tab_new);
254 	global_set_key("g t",		cmd_tab_next);
255 	global_set_key("g T",		cmd_tab_previous);
256 	global_set_key("g M-t",		cmd_tab_move);
257 	global_set_key("g M-T",		cmd_tab_move_to);
258 
259 	global_set_key("H",		cmd_previous_page);
260 	global_set_key("L",		cmd_next_page);
261 
262 	/* tmp */
263 	global_set_key("q",		cmd_kill_telescope);
264 
265 	global_set_key("esc",		cmd_clear_minibuf);
266 
267 	global_set_key(":",		cmd_execute_extended_command);
268 
269 	/* cua */
270 	global_set_key("<up>",		cmd_previous_line);
271 	global_set_key("<down>",	cmd_next_line);
272 	global_set_key("<right>",	cmd_forward_char);
273 	global_set_key("<left>",	cmd_backward_char);
274 	global_set_key("<prior>",	cmd_scroll_up);
275 	global_set_key("<next>",	cmd_scroll_down);
276 
277 	global_set_key("M-<left>",	cmd_previous_page);
278 	global_set_key("M-<right>",	cmd_next_page);
279 
280 	/* "ncurses standard" */
281 	global_set_key("C-l",		cmd_redraw);
282 
283 	/* global */
284 	global_set_key("<f1>",		cmd_toggle_help);
285 	global_set_key("C-m",		cmd_push_button);
286 	global_set_key("M-enter",	cmd_push_button_new_tab);
287 	global_set_key("M-tab",		cmd_previous_button);
288 	global_set_key("backtab",	cmd_previous_button);
289 	global_set_key("tab",		cmd_next_button);
290 
291 	/* === minibuffer map === */
292 	minibuffer_set_key("ret",		cmd_mini_complete_and_exit);
293 	minibuffer_set_key("C-g",		cmd_mini_abort);
294 	minibuffer_set_key("esc",		cmd_mini_abort);
295 	minibuffer_set_key("C-d",		cmd_mini_delete_char);
296 	minibuffer_set_key("del",		cmd_mini_delete_backward_char);
297 	minibuffer_set_key("backspace",		cmd_mini_delete_backward_char);
298 	minibuffer_set_key("C-h",		cmd_mini_delete_backward_char);
299 
300 	minibuffer_set_key("C-b",		cmd_backward_char);
301 	minibuffer_set_key("C-f",		cmd_forward_char);
302 	minibuffer_set_key("<left>",		cmd_backward_char);
303 	minibuffer_set_key("<right>",		cmd_forward_char);
304 	minibuffer_set_key("C-e",		cmd_move_end_of_line);
305 	minibuffer_set_key("C-a",		cmd_move_beginning_of_line);
306 	minibuffer_set_key("<end>",		cmd_move_end_of_line);
307 	minibuffer_set_key("<home>",		cmd_move_beginning_of_line);
308 	minibuffer_set_key("C-k",		cmd_mini_kill_line);
309 
310 	minibuffer_set_key("M-p",		cmd_mini_previous_history_element);
311 	minibuffer_set_key("M-n",		cmd_mini_next_history_element);
312 	minibuffer_set_key("<up>",		cmd_mini_previous_history_element);
313 	minibuffer_set_key("<down>",		cmd_mini_next_history_element);
314 }
315 
316 static void
317 restore_cursor(struct buffer *buffer)
318 {
319 	struct vline	*vl;
320 	const char	*prfx;
321 
322 	vl = buffer->current_line;
323 	if (vl == NULL || vl->line == NULL)
324 		buffer->curs_x = buffer->cpoff = 0;
325 	else
326 		buffer->curs_x = utf8_snwidth(vl->line, buffer->cpoff);
327 
328 	buffer->curs_x += x_offset;
329 
330 	if (vl != NULL) {
331 		prfx = line_prefixes[vl->parent->type].prfx1;
332 		buffer->curs_x += utf8_swidth(prfx);
333 	}
334 }
335 
336 void
337 cmd_previous_line(struct buffer *buffer)
338 {
339 	struct vline	*vl;
340 
341 	if (buffer->current_line == NULL
342 	    || (vl = TAILQ_PREV(buffer->current_line, vhead, vlines)) == NULL)
343 		return;
344 
345 	if (--buffer->curs_y < 0) {
346 		buffer->curs_y = 0;
347 		cmd_scroll_line_up(buffer);
348 		return;
349 	}
350 
351 	buffer->current_line = vl;
352 	restore_cursor(buffer);
353 }
354 
355 void
356 cmd_next_line(struct buffer *buffer)
357 {
358 	struct vline	*vl;
359 
360 	if (buffer->current_line == NULL
361 	    || (vl = TAILQ_NEXT(buffer->current_line, vlines)) == NULL)
362 		return;
363 
364 	if (++buffer->curs_y > body_lines-1) {
365 		buffer->curs_y = body_lines-1;
366 		cmd_scroll_line_down(buffer);
367 		return;
368 	}
369 
370 	buffer->current_line = vl;
371 	restore_cursor(buffer);
372 }
373 
374 void
375 cmd_backward_char(struct buffer *buffer)
376 {
377 	if (buffer->cpoff != 0)
378 		buffer->cpoff--;
379 	restore_cursor(buffer);
380 }
381 
382 void
383 cmd_forward_char(struct buffer *buffer)
384 {
385 	size_t len = 0;
386 
387 	if (buffer->current_line->line != NULL)
388 		len = utf8_cplen(buffer->current_line->line);
389 	if (++buffer->cpoff > len)
390 		buffer->cpoff = len;
391 	restore_cursor(buffer);
392 }
393 
394 void
395 cmd_backward_paragraph(struct buffer *buffer)
396 {
397 	do {
398 		if (buffer->current_line == NULL ||
399 		    buffer->current_line == TAILQ_FIRST(&buffer->head)) {
400 			message("No previous paragraph");
401 			return;
402 		}
403 		cmd_previous_line(buffer);
404 	} while (buffer->current_line->line != NULL ||
405 	    buffer->current_line->parent->type != LINE_TEXT);
406 }
407 
408 void
409 cmd_forward_paragraph(struct buffer *buffer)
410 {
411 	do {
412 		if (buffer->current_line == NULL ||
413 		    buffer->current_line == TAILQ_LAST(&buffer->head, vhead)) {
414 			message("No next paragraph");
415 			return;
416 		}
417 		cmd_next_line(buffer);
418 	} while (buffer->current_line->line != NULL ||
419 	    buffer->current_line->parent->type != LINE_TEXT);
420 }
421 
422 void
423 cmd_move_beginning_of_line(struct buffer *buffer)
424 {
425 	buffer->cpoff = 0;
426 	restore_cursor(buffer);
427 }
428 
429 void
430 cmd_move_end_of_line(struct buffer *buffer)
431 {
432 	struct vline	*vl;
433 
434 	vl = buffer->current_line;
435 	if (vl->line == NULL)
436 		return;
437 	buffer->cpoff = utf8_cplen(vl->line);
438 	restore_cursor(buffer);
439 }
440 
441 void
442 cmd_redraw(struct buffer *buffer)
443 {
444 	handle_resize(0, 0, NULL);
445 }
446 
447 void
448 cmd_scroll_line_up(struct buffer *buffer)
449 {
450 	struct vline	*vl;
451 
452 	if (buffer->line_off == 0)
453 		return;
454 
455 	vl = nth_line(buffer, --buffer->line_off);
456 	wscrl(body, -1);
457 	wmove(body, 0, 0);
458 	print_vline(body, vl);
459 
460 	buffer->current_line = TAILQ_PREV(buffer->current_line, vhead, vlines);
461 	restore_cursor(buffer);
462 }
463 
464 void
465 cmd_scroll_line_down(struct buffer *buffer)
466 {
467 	struct vline	*vl;
468 
469 	vl = buffer->current_line;
470 	if ((vl = TAILQ_NEXT(vl, vlines)) == NULL)
471 		return;
472 	buffer->current_line = vl;
473 
474 	buffer->line_off++;
475 	wscrl(body, 1);
476 
477 	if (buffer->line_max - buffer->line_off < (size_t)body_lines)
478 		return;
479 
480 	vl = nth_line(buffer, buffer->line_off + body_lines-1);
481 	wmove(body, body_lines-1, 0);
482 	print_vline(body, vl);
483 
484 	restore_cursor(buffer);
485 }
486 
487 void
488 cmd_scroll_up(struct buffer *buffer)
489 {
490 	size_t off;
491 
492 	off = body_lines-1;
493 
494 	for (; off > 0; --off)
495 		cmd_scroll_line_up(buffer);
496 }
497 
498 void
499 cmd_scroll_down(struct buffer *buffer)
500 {
501 	size_t off;
502 
503 	off = body_lines-1;
504 
505 	for (; off > 0; --off)
506 		cmd_scroll_line_down(buffer);
507 }
508 
509 void
510 cmd_beginning_of_buffer(struct buffer *buffer)
511 {
512 	buffer->current_line = TAILQ_FIRST(&buffer->head);
513 	buffer->line_off = 0;
514 	buffer->curs_y = 0;
515 	buffer->cpoff = 0;
516 	restore_cursor(buffer);
517 }
518 
519 void
520 cmd_end_of_buffer(struct buffer *buffer)
521 {
522 	ssize_t off;
523 
524 	off = buffer->line_max - body_lines;
525 	off = MAX(0, off);
526 
527 	buffer->line_off = off;
528 	buffer->curs_y = MIN((size_t)body_lines, buffer->line_max-1);
529 
530 	buffer->current_line = TAILQ_LAST(&buffer->head, vhead);
531 	buffer->cpoff = body_cols;
532 	restore_cursor(buffer);
533 }
534 
535 void
536 cmd_kill_telescope(struct buffer *buffer)
537 {
538 	save_session();
539 	event_loopbreak();
540 }
541 
542 void
543 cmd_push_button(struct buffer *buffer)
544 {
545 	struct vline	*vl;
546 	size_t		 nth;
547 
548 	nth = buffer->line_off + buffer->curs_y;
549 	if (nth >= buffer->line_max)
550 		return;
551 	vl = nth_line(buffer, nth);
552 	if (vl->parent->type != LINE_LINK)
553 		return;
554 
555 	load_url_in_tab(current_tab(), vl->parent->alt);
556 }
557 
558 void
559 cmd_push_button_new_tab(struct buffer *buffer)
560 {
561 	struct vline	*vl;
562 	size_t		 nth;
563 
564 	nth = buffer->line_off + buffer->curs_y;
565 	if (nth > buffer->line_max)
566 		return;
567 	vl = nth_line(buffer, nth);
568 	if (vl->parent->type != LINE_LINK)
569 		return;
570 
571 	new_tab(vl->parent->alt);
572 }
573 
574 void
575 cmd_previous_button(struct buffer *buffer)
576 {
577 	do {
578 		if (buffer->current_line == NULL ||
579 		    buffer->current_line == TAILQ_FIRST(&buffer->head)) {
580 			message("No previous link");
581 			return;
582 		}
583 		cmd_previous_line(buffer);
584 	} while (buffer->current_line->parent->type != LINE_LINK);
585 }
586 
587 void
588 cmd_next_button(struct buffer *buffer)
589 {
590 	do {
591 		if (buffer->current_line == NULL ||
592 		    buffer->current_line == TAILQ_LAST(&buffer->head, vhead)) {
593 			message("No next link");
594 			return;
595 		}
596 		cmd_next_line(buffer);
597 	} while (buffer->current_line->parent->type != LINE_LINK);
598 }
599 
600 void
601 cmd_previous_page(struct buffer *buffer)
602 {
603 	struct tab *tab = current_tab();
604 
605 	if (!load_previous_page(tab))
606 		message("No previous page");
607 	else
608 		start_loading_anim(tab);
609 }
610 
611 void
612 cmd_next_page(struct buffer *buffer)
613 {
614 	struct tab *tab = current_tab();
615 
616 	if (!load_next_page(tab))
617 		message("No next page");
618 	else
619 		start_loading_anim(tab);
620 }
621 
622 void
623 cmd_clear_minibuf(struct buffer *buffer)
624 {
625 	handle_clear_minibuf(0, 0, NULL);
626 }
627 
628 void
629 cmd_execute_extended_command(struct buffer *buffer)
630 {
631 	size_t	 len;
632 
633 	if (in_minibuffer) {
634 		message("We don't have enable-recursive-minibuffers");
635 		return;
636 	}
637 
638 	enter_minibuffer(eecmd_self_insert, eecmd_select, exit_minibuffer,
639 	    &eecmd_history);
640 
641 	len = sizeof(ministate.prompt);
642 	strlcpy(ministate.prompt, "", len);
643 
644 	if (thiskey.meta)
645 		strlcat(ministate.prompt, "M-", len);
646 
647 	strlcat(ministate.prompt, keyname(thiskey.key), len);
648 
649 	if (thiskey.meta)
650 		strlcat(ministate.prompt, " ", len);
651 }
652 
653 void
654 cmd_tab_close(struct buffer *buffer)
655 {
656 	struct tab *tab, *t;
657 
658 	tab = current_tab();
659 	if (TAILQ_PREV(tab, tabshead, tabs) == NULL &&
660 	    TAILQ_NEXT(tab, tabs) == NULL) {
661 		message("Can't close the only tab.");
662 		return;
663 	}
664 
665 	if (evtimer_pending(&tab->loadingev, NULL))
666 		evtimer_del(&tab->loadingev);
667 
668 	stop_tab(tab);
669 
670 	if ((t = TAILQ_PREV(tab, tabshead, tabs)) == NULL)
671 		t = TAILQ_NEXT(tab, tabs);
672 	TAILQ_REMOVE(&tabshead, tab, tabs);
673 	free(tab);
674 
675 	switch_to_tab(t);
676 }
677 
678 void
679 cmd_tab_close_other(struct buffer *buffer)
680 {
681 	struct tab *t, *i;
682 
683 	TAILQ_FOREACH_SAFE(t, &tabshead, tabs, i) {
684 		if (t->flags & TAB_CURRENT)
685 			continue;
686 
687 		stop_tab(t);
688 		TAILQ_REMOVE(&tabshead, t, tabs);
689 		free(t);
690 	}
691 }
692 
693 void
694 cmd_tab_new(struct buffer *buffer)
695 {
696 	const char *url;
697 
698 	if ((url = new_tab_url) == NULL)
699 		url = NEW_TAB_URL;
700 
701 	new_tab(url);
702 }
703 
704 void
705 cmd_tab_next(struct buffer *buffer)
706 {
707 	struct tab *tab, *t;
708 
709 	tab = current_tab();
710 	tab->flags &= ~TAB_CURRENT;
711 
712 	if ((t = TAILQ_NEXT(tab, tabs)) == NULL)
713 		t = TAILQ_FIRST(&tabshead);
714 	t->flags |= TAB_CURRENT;
715 	t->flags &= ~TAB_URGENT;
716 }
717 
718 void
719 cmd_tab_previous(struct buffer *buffer)
720 {
721 	struct tab *tab, *t;
722 
723 	tab = current_tab();
724 	tab->flags &= ~TAB_CURRENT;
725 
726 	if ((t = TAILQ_PREV(tab, tabshead, tabs)) == NULL)
727 		t = TAILQ_LAST(&tabshead, tabshead);
728 	t->flags |= TAB_CURRENT;
729 	t->flags &= ~TAB_URGENT;
730 }
731 
732 void
733 cmd_tab_move(struct buffer *buffer)
734 {
735 	struct tab *tab, *t;
736 
737 	tab = current_tab();
738 	t = TAILQ_NEXT(tab, tabs);
739 	TAILQ_REMOVE(&tabshead, tab, tabs);
740 
741 	if (t == NULL)
742 		TAILQ_INSERT_HEAD(&tabshead, tab, tabs);
743 	else
744 		TAILQ_INSERT_AFTER(&tabshead, t, tab, tabs);
745 }
746 
747 void
748 cmd_tab_move_to(struct buffer *buffer)
749 {
750 	struct tab *tab, *t;
751 
752 	tab = current_tab();
753 	t = TAILQ_PREV(tab, tabshead, tabs);
754 	TAILQ_REMOVE(&tabshead, tab, tabs);
755 
756 	if (t == NULL) {
757 		if (TAILQ_EMPTY(&tabshead))
758 			TAILQ_INSERT_HEAD(&tabshead, tab, tabs);
759 		else
760 			TAILQ_INSERT_TAIL(&tabshead, tab, tabs);
761 	} else
762 		TAILQ_INSERT_BEFORE(t, tab, tabs);
763 }
764 
765 void
766 cmd_load_url(struct buffer *buffer)
767 {
768 	if (in_minibuffer) {
769 		message("We don't have enable-recursive-minibuffers");
770 		return;
771 	}
772 
773 	enter_minibuffer(lu_self_insert, lu_select, exit_minibuffer,
774 	    &lu_history);
775 	strlcpy(ministate.prompt, "Load URL: ", sizeof(ministate.prompt));
776 	strlcpy(ministate.buf, "gemini://", sizeof(ministate.buf));
777 	cmd_move_end_of_line(&ministate.buffer);
778 }
779 
780 void
781 cmd_load_current_url(struct buffer *buffer)
782 {
783 	struct tab *tab = current_tab();
784 
785 	if (in_minibuffer) {
786 		message("We don't have enable-recursive-minibuffers");
787 		return;
788 	}
789 
790 	enter_minibuffer(lu_self_insert, lu_select, exit_minibuffer,
791 	    &lu_history);
792 	strlcpy(ministate.prompt, "Load URL: ", sizeof(ministate.prompt));
793 	strlcpy(ministate.buf, tab->hist_cur->h, sizeof(ministate.buf));
794 	ministate.buffer.cpoff = utf8_cplen(ministate.buf);
795 }
796 
797 void
798 cmd_bookmark_page(struct buffer *buffer)
799 {
800 	struct tab *tab = current_tab();
801 
802 	enter_minibuffer(lu_self_insert, bp_select, exit_minibuffer, NULL);
803 	strlcpy(ministate.prompt, "Bookmark URL: ", sizeof(ministate.prompt));
804 	strlcpy(ministate.buf, tab->hist_cur->h, sizeof(ministate.buf));
805 	ministate.buffer.cpoff = utf8_cplen(ministate.buf);
806 }
807 
808 void
809 cmd_list_bookmarks(struct buffer *buffer)
810 {
811 	load_url_in_tab(current_tab(), "about:bookmarks");
812 }
813 
814 void
815 cmd_toggle_help(struct buffer *buffer)
816 {
817 	side_window = !side_window;
818 	if (side_window)
819 		recompute_help();
820 
821 	/*
822 	 * ugly hack, but otherwise the window doesn't get updated
823 	 * until I call handle_resize a second time (i.e. C-l).  I
824 	 * will be happy to know why something like this is needed.
825 	 */
826 	handle_resize_nodelay(0, 0, NULL);
827 	handle_resize_nodelay(0, 0, NULL);
828 }
829 
830 void
831 cmd_olivetti_mode(struct buffer *buffer)
832 {
833 	olivetti_mode = !olivetti_mode;
834 	if (olivetti_mode)
835 		message("olivetti-mode enabled");
836 	else
837 		message("olivetti-mode disabled");
838 
839 	handle_resize_nodelay(0, 0, NULL);
840 }
841 
842 void
843 cmd_mini_delete_char(struct buffer *buffer)
844 {
845 	char *c, *n;
846 
847 	if (!in_minibuffer) {
848 		message("text is read-only");
849 		return;
850 	}
851 
852 	minibuffer_taint_hist();
853 
854 	c = utf8_nth(buffer->current_line->line, buffer->cpoff);
855 	if (*c == '\0')
856 		return;
857 	n = utf8_next_cp(c);
858 
859 	memmove(c, n, strlen(n)+1);
860 }
861 
862 void
863 cmd_mini_delete_backward_char(struct buffer *buffer)
864 {
865 	char *c, *p, *start;
866 
867 	if (!in_minibuffer) {
868 		message("text is read-only");
869 		return;
870 	}
871 
872 	minibuffer_taint_hist();
873 
874 	c = utf8_nth(buffer->current_line->line, buffer->cpoff);
875 	start = buffer->current_line->line;
876 	if (c == start)
877 		return;
878 	p = utf8_prev_cp(c-1, start);
879 
880 	memmove(p, c, strlen(c)+1);
881 	buffer->cpoff--;
882 }
883 
884 void
885 cmd_mini_kill_line(struct buffer *buffer)
886 {
887 	char *c;
888 
889 	if (!in_minibuffer) {
890 		message("text is read-only");
891 		return;
892 	}
893 
894 	minibuffer_taint_hist();
895 	c = utf8_nth(buffer->current_line->line, buffer->cpoff);
896 	*c = '\0';
897 }
898 
899 void
900 cmd_mini_abort(struct buffer *buffer)
901 {
902 	if (!in_minibuffer)
903 		return;
904 
905 	ministate.abortfn();
906 }
907 
908 void
909 cmd_mini_complete_and_exit(struct buffer *buffer)
910 {
911 	if (!in_minibuffer)
912 		return;
913 
914 	minibuffer_taint_hist();
915 	ministate.donefn();
916 }
917 
918 void
919 cmd_mini_previous_history_element(struct buffer *buffer)
920 {
921 	if (ministate.history == NULL) {
922 		message("No history");
923 		return;
924 	}
925 
926 	if (ministate.hist_cur == NULL ||
927 	    (ministate.hist_cur = TAILQ_PREV(ministate.hist_cur, mhisthead, entries)) == NULL) {
928 		ministate.hist_cur = TAILQ_LAST(&ministate.history->head, mhisthead);
929 		ministate.hist_off = ministate.history->len - 1;
930 		if (ministate.hist_cur == NULL)
931 			message("No prev item");
932 	} else {
933 		ministate.hist_off--;
934 	}
935 
936 	if (ministate.hist_cur != NULL)
937 		buffer->current_line->line = ministate.hist_cur->h;
938 }
939 
940 void
941 cmd_mini_next_history_element(struct buffer *buffer)
942 {
943 	if (ministate.history == NULL) {
944 		message("No history");
945 		return;
946 	}
947 
948 	if (ministate.hist_cur == NULL ||
949 	    (ministate.hist_cur = TAILQ_NEXT(ministate.hist_cur, entries)) == NULL) {
950 		ministate.hist_cur = TAILQ_FIRST(&ministate.history->head);
951 		ministate.hist_off = 0;
952 		if (ministate.hist_cur == NULL)
953 			message("No next item");
954 	} else {
955 		ministate.hist_off++;
956 	}
957 
958 	if (ministate.hist_cur != NULL)
959 		buffer->current_line->line = ministate.hist_cur->h;
960 }
961 
962 static void
963 global_key_unbound(void)
964 {
965 	message("%s is undefined", keybuf);
966 }
967 
968 static void
969 minibuffer_hist_save_entry(void)
970 {
971 	struct hist	*hist;
972 
973 	if (ministate.history == NULL)
974 		return;
975 
976 	if ((hist = calloc(1, sizeof(*hist))) == NULL)
977 		abort();
978 
979 	strlcpy(hist->h, ministate.buf, sizeof(hist->h));
980 
981 	if (TAILQ_EMPTY(&ministate.history->head))
982 		TAILQ_INSERT_HEAD(&ministate.history->head, hist, entries);
983 	else
984 		TAILQ_INSERT_TAIL(&ministate.history->head, hist, entries);
985 	ministate.history->len++;
986 }
987 
988 /*
989  * taint the minibuffer cache: if we're currently showing a history
990  * element, copy that to the current buf and reset the "history
991  * navigation" thing.
992  */
993 static void
994 minibuffer_taint_hist(void)
995 {
996 	if (ministate.hist_cur == NULL)
997 		return;
998 
999 	strlcpy(ministate.buf, ministate.hist_cur->h, sizeof(ministate.buf));
1000 	ministate.hist_cur = NULL;
1001 }
1002 
1003 static void
1004 minibuffer_self_insert(void)
1005 {
1006 	char	*c, tmp[5] = {0};
1007 	size_t	len;
1008 
1009 	minibuffer_taint_hist();
1010 
1011 	if (thiskey.cp == 0)
1012 		return;
1013 
1014 	len = utf8_encode(thiskey.cp, tmp);
1015 	c = utf8_nth(ministate.buffer.current_line->line, ministate.buffer.cpoff);
1016 	if (c + len > ministate.buf + sizeof(ministate.buf) - 1)
1017 		return;
1018 
1019 	memmove(c + len, c, strlen(c)+1);
1020 	memcpy(c, tmp, len);
1021 	ministate.buffer.cpoff++;
1022 }
1023 
1024 static void
1025 eecmd_self_insert(void)
1026 {
1027 	if (thiskey.meta || unicode_isspace(thiskey.cp) ||
1028 	    !unicode_isgraph(thiskey.cp)) {
1029 		global_key_unbound();
1030 		return;
1031 	}
1032 
1033 	minibuffer_self_insert();
1034 }
1035 
1036 static void
1037 eecmd_select(void)
1038 {
1039 	struct cmds *cmd;
1040 
1041 	for (cmd = cmds; cmd->cmd != NULL; ++cmd) {
1042 		if (!strcmp(cmd->cmd, ministate.buf)) {
1043 			exit_minibuffer();
1044 			minibuffer_hist_save_entry();
1045 			cmd->fn(current_buffer());
1046 			return;
1047 		}
1048 	}
1049 
1050 	message("No match");
1051 }
1052 
1053 static void
1054 ir_self_insert(void)
1055 {
1056 	minibuffer_self_insert();
1057 }
1058 
1059 static void
1060 ir_select(void)
1061 {
1062 	char		 buf[1025] = {0};
1063 	struct phos_uri	 uri;
1064 	struct tab	*tab;
1065 
1066 	tab = current_tab();
1067 
1068 	exit_minibuffer();
1069 	minibuffer_hist_save_entry();
1070 
1071 	/* a bit ugly but... */
1072 	memcpy(&uri, &tab->uri, sizeof(tab->uri));
1073 	phos_uri_set_query(&uri, ministate.buf);
1074 	phos_serialize_uri(&uri, buf, sizeof(buf));
1075 	load_url_in_tab(tab, buf);
1076 }
1077 
1078 static void
1079 lu_self_insert(void)
1080 {
1081 	if (thiskey.meta || unicode_isspace(thiskey.key) ||
1082 	    !unicode_isgraph(thiskey.key)) {
1083 		global_key_unbound();
1084 		return;
1085 	}
1086 
1087 	minibuffer_self_insert();
1088 }
1089 
1090 static void
1091 lu_select(void)
1092 {
1093 	exit_minibuffer();
1094 	minibuffer_hist_save_entry();
1095 	load_url_in_tab(current_tab(), ministate.buf);
1096 }
1097 
1098 static void
1099 bp_select(void)
1100 {
1101 	exit_minibuffer();
1102 	if (*ministate.buf != '\0')
1103 		add_to_bookmarks(ministate.buf);
1104 	else
1105 		message("Abort.");
1106 }
1107 
1108 static void
1109 yornp_self_insert(void)
1110 {
1111 	if (thiskey.key != 'y' && thiskey.key != 'n') {
1112 		message("Please answer y or n");
1113 		return;
1114 	}
1115 
1116 	exit_minibuffer();
1117 	yornp_cb(thiskey.key == 'y', yornp_data);
1118 }
1119 
1120 static void
1121 yornp_abort(void)
1122 {
1123 	exit_minibuffer();
1124 	yornp_cb(0, yornp_data);
1125 }
1126 
1127 static void
1128 read_self_insert(void)
1129 {
1130 	if (thiskey.meta || !unicode_isgraph(thiskey.cp)) {
1131 		global_key_unbound();
1132 		return;
1133 	}
1134 
1135 	minibuffer_self_insert();
1136 }
1137 
1138 static void
1139 read_abort(void)
1140 {
1141 	exit_minibuffer();
1142 	read_cb(NULL, read_data);
1143 }
1144 
1145 static void
1146 read_select(void)
1147 {
1148         exit_minibuffer();
1149 	minibuffer_hist_save_entry();
1150 	read_cb(ministate.buf, read_data);
1151 }
1152 
1153 static struct vline *
1154 nth_line(struct buffer *buffer, size_t n)
1155 {
1156 	struct vline	*vl;
1157 	size_t		 i;
1158 
1159 	i = 0;
1160 	TAILQ_FOREACH(vl, &buffer->head, vlines) {
1161 		if (i == n)
1162 			return vl;
1163 		i++;
1164 	}
1165 
1166 	/* unreachable */
1167 	abort();
1168 }
1169 
1170 static struct tab *
1171 current_tab(void)
1172 {
1173 	struct tab *t;
1174 
1175 	TAILQ_FOREACH(t, &tabshead, tabs) {
1176 		if (t->flags & TAB_CURRENT)
1177 			return t;
1178 	}
1179 
1180 	/* unreachable */
1181 	abort();
1182 }
1183 
1184 static struct buffer *
1185 current_buffer(void)
1186 {
1187 	if (in_minibuffer)
1188 		return &ministate.buffer;
1189 	return &current_tab()->buffer;
1190 }
1191 
1192 static int
1193 readkey(void)
1194 {
1195 	uint32_t state = 0;
1196 
1197 	if ((thiskey.key = wgetch(body)) == ERR)
1198 		return 0;
1199 
1200 	thiskey.meta = thiskey.key == 27;
1201 	if (thiskey.meta) {
1202 		thiskey.key = wgetch(body);
1203 		if (thiskey.key == ERR || thiskey.key == 27) {
1204 			thiskey.meta = 0;
1205 			thiskey.key = 27;
1206 		}
1207 	}
1208 
1209 	thiskey.cp = 0;
1210 	if ((unsigned int)thiskey.key < UINT8_MAX) {
1211 		while (1) {
1212 			if (!utf8_decode(&state, &thiskey.cp, (uint8_t)thiskey.key))
1213 				break;
1214 			if ((thiskey.key = wgetch(body)) == ERR) {
1215 				message("Error decoding user input");
1216 				return 0;
1217 			}
1218 		}
1219 	}
1220 
1221 	return 1;
1222 }
1223 
1224 static void
1225 dispatch_stdio(int fd, short ev, void *d)
1226 {
1227 	struct keymap	*k;
1228 	const char	*keyname;
1229 	char		 tmp[5] = {0};
1230 
1231 	if (!readkey())
1232 		return;
1233 
1234 	if (keybuf[0] != '\0')
1235 		strlcat(keybuf, " ", sizeof(keybuf));
1236 	if (thiskey.meta)
1237 		strlcat(keybuf, "M-", sizeof(keybuf));
1238 	if (thiskey.cp != 0) {
1239 		utf8_encode(thiskey.cp, tmp);
1240 		strlcat(keybuf, tmp, sizeof(keybuf));
1241 	} else {
1242 		if ((keyname = unkbd(thiskey.key)) != NULL)
1243 			strlcat(keybuf, keyname, sizeof(keybuf));
1244 		else {
1245 			tmp[0] = thiskey.key;
1246 			strlcat(keybuf, tmp, sizeof(keybuf));
1247 		}
1248 	}
1249 
1250 	TAILQ_FOREACH(k, &current_map->m, keymaps) {
1251 		if (k->meta == thiskey.meta &&
1252 		    k->key == thiskey.key) {
1253 			if (k->fn == NULL)
1254 				current_map = &k->map;
1255 			else {
1256 				current_map = base_map;
1257 				strlcpy(keybuf, "", sizeof(keybuf));
1258 				k->fn(current_buffer());
1259 			}
1260 			goto done;
1261 		}
1262 	}
1263 
1264 	if (current_map->unhandled_input != NULL)
1265 		current_map->unhandled_input();
1266 	else {
1267 		global_key_unbound();
1268 	}
1269 
1270 	strlcpy(keybuf, "", sizeof(keybuf));
1271 	current_map = base_map;
1272 
1273 done:
1274 	if (side_window)
1275 		recompute_help();
1276 
1277 	redraw_tab(current_tab());
1278 }
1279 
1280 static void
1281 handle_clear_minibuf(int fd, short ev, void *d)
1282 {
1283 	free(ministate.curmesg);
1284 	ministate.curmesg = NULL;
1285 
1286 	redraw_minibuffer();
1287 	if (in_minibuffer) {
1288 		wrefresh(body);
1289 		wrefresh(minibuf);
1290 	} else {
1291 		wrefresh(minibuf);
1292 		wrefresh(body);
1293 	}
1294 }
1295 
1296 static void
1297 handle_resize(int sig, short ev, void *d)
1298 {
1299 	if (event_pending(&resizeev, EV_TIMEOUT, NULL)) {
1300 		event_del(&resizeev);
1301 	}
1302 	evtimer_set(&resizeev, handle_resize_nodelay, NULL);
1303 	evtimer_add(&resizeev, &resize_timer);
1304 }
1305 
1306 static void
1307 handle_resize_nodelay(int s, short ev, void *d)
1308 {
1309 	struct tab	*tab;
1310 
1311 	endwin();
1312 	refresh();
1313 	clear();
1314 
1315 	/* move and resize the windows, in reverse order! */
1316 
1317 	mvwin(minibuf, LINES-1, 0);
1318 	wresize(minibuf, 1, COLS);
1319 
1320 	mvwin(modeline, LINES-2, 0);
1321 	wresize(modeline, 1, COLS);
1322 
1323 	body_lines = LINES-3;
1324 	body_cols = COLS;
1325 
1326 	if (side_window) {
1327 		help_cols = 0.3 * COLS;
1328 		help_lines = LINES-3;
1329 		mvwin(help, 1, 0);
1330 		wresize(help, help_lines, help_cols);
1331 
1332 		wrap_page(&helpwin, help_cols);
1333 
1334 		body_cols = COLS - help_cols - 1;
1335 		mvwin(body, 1, help_cols);
1336 	} else
1337 		mvwin(body, 1, 0);
1338 
1339 	update_x_offset();
1340 	wresize(body, body_lines, body_cols);
1341 
1342 	wresize(tabline, 1, COLS);
1343 
1344 	tab = current_tab();
1345 
1346 	wrap_page(&tab->buffer, body_cols);
1347 	redraw_tab(tab);
1348 }
1349 
1350 static int
1351 wrap_page(struct buffer *buffer, int width)
1352 {
1353 	struct line		*l;
1354 	const struct line	*orig;
1355 	struct vline		*vl;
1356 	int			 pre_width;
1357 	const char		*prfx;
1358 
1359 	orig = buffer->current_line == NULL
1360 		? NULL
1361 		: buffer->current_line->parent;
1362 	buffer->current_line = NULL;
1363 
1364 	buffer->curs_y = 0;
1365 	buffer->line_off = 0;
1366 
1367 	empty_vlist(buffer);
1368 
1369 	TAILQ_FOREACH(l, &buffer->page.head, lines) {
1370 		prfx = line_prefixes[l->type].prfx1;
1371 		switch (l->type) {
1372 		case LINE_TEXT:
1373 		case LINE_LINK:
1374 		case LINE_TITLE_1:
1375 		case LINE_TITLE_2:
1376 		case LINE_TITLE_3:
1377 		case LINE_ITEM:
1378 		case LINE_QUOTE:
1379 		case LINE_PRE_START:
1380 		case LINE_PRE_END:
1381 			wrap_text(buffer, prfx, l, MIN(fill_column, width));
1382 			break;
1383 		case LINE_PRE_CONTENT:
1384 			if (olivetti_mode)
1385 				pre_width = MIN(fill_column, width);
1386 			else
1387 				pre_width = width;
1388 			hardwrap_text(buffer, l, pre_width);
1389 			break;
1390 		}
1391 
1392 		if (orig == l && buffer->current_line == NULL) {
1393 			buffer->line_off = buffer->line_max-1;
1394 			buffer->current_line = TAILQ_LAST(&buffer->head, vhead);
1395 
1396 			while (1) {
1397 				vl = TAILQ_PREV(buffer->current_line, vhead, vlines);
1398 				if (vl == NULL || vl->parent != orig)
1399 					break;
1400 				buffer->current_line = vl;
1401 				buffer->line_off--;
1402 			}
1403 		}
1404 	}
1405 
1406         if (buffer->current_line == NULL)
1407 		buffer->current_line = TAILQ_FIRST(&buffer->head);
1408 
1409 	return 1;
1410 }
1411 
1412 static void
1413 print_vline(WINDOW *window, struct vline *vl)
1414 {
1415 	const char *text = vl->line;
1416 	const char *prfx;
1417 	int prefix_face = line_faces[vl->parent->type].prefix_prop;
1418 	int text_face = line_faces[vl->parent->type].text_prop;
1419 
1420 	if (!vl->flags)
1421 		prfx = line_prefixes[vl->parent->type].prfx1;
1422 	else
1423 		prfx = line_prefixes[vl->parent->type].prfx2;
1424 
1425 	if (text == NULL)
1426 		text = "";
1427 
1428 	wattron(window, prefix_face);
1429 	wprintw(window, "%s", prfx);
1430 	wattroff(window, prefix_face);
1431 
1432 	wattron(window, text_face);
1433 	wprintw(window, "%s", text);
1434 	wattroff(window, text_face);
1435 }
1436 
1437 static void
1438 redraw_tabline(void)
1439 {
1440 	struct tab	*tab;
1441 	size_t		 toskip, ots, tabwidth, space, x;
1442 	int		 current, y, truncated;
1443 	const char	*title;
1444 	char		 buf[25];
1445 
1446 	tabwidth = sizeof(buf)+1;
1447 	space = COLS-2;
1448 
1449 	toskip = 0;
1450 	TAILQ_FOREACH(tab, &tabshead, tabs) {
1451 		toskip++;
1452 		if (tab->flags & TAB_CURRENT)
1453 			break;
1454 	}
1455 
1456 	if (toskip * tabwidth < space)
1457 		toskip = 0;
1458 	else {
1459 		ots = toskip;
1460 		toskip--;
1461                 while (toskip != 0 &&
1462 		    (ots - toskip+1) * tabwidth < space)
1463 			toskip--;
1464 	}
1465 
1466 	werase(tabline);
1467 	wattron(tabline, tab_face.background);
1468 	wprintw(tabline, toskip == 0 ? " " : "<");
1469 	wattroff(tabline, tab_face.background);
1470 
1471 	truncated = 0;
1472 	TAILQ_FOREACH(tab, &tabshead, tabs) {
1473 		if (truncated)
1474 			break;
1475 		if (toskip != 0) {
1476 			toskip--;
1477 			continue;
1478 		}
1479 
1480 		getyx(tabline, y, x);
1481 		if (x + sizeof(buf)+2 >= (size_t)COLS)
1482 			truncated = 1;
1483 
1484 		current = tab->flags & TAB_CURRENT;
1485 
1486 		if (*(title = tab->buffer.page.title) == '\0')
1487 			title = tab->hist_cur->h;
1488 
1489 		if (tab->flags & TAB_URGENT)
1490 			strlcpy(buf, "!", sizeof(buf));
1491 		else
1492 			strlcpy(buf, " ", sizeof(buf));
1493 
1494                 if (strlcat(buf, title, sizeof(buf)) >= sizeof(buf)) {
1495 			/* truncation happens */
1496 			strlcpy(&buf[sizeof(buf)-4], "...", 4);
1497 		} else {
1498 			/* pad with spaces */
1499 			while (strlcat(buf, "    ", sizeof(buf)) < sizeof(buf))
1500 				/* nop */ ;
1501 		}
1502 
1503 		if (current)
1504 			wattron(tabline, tab_face.current_tab);
1505 		else
1506 			wattron(tabline, tab_face.tab);
1507 
1508 		wprintw(tabline, "%s", buf);
1509 		if (TAILQ_NEXT(tab, tabs) != NULL)
1510 			wprintw(tabline, " ");
1511 
1512 		if (current)
1513 			wattroff(tabline, tab_face.current_tab);
1514 		else
1515 			wattroff(tabline, tab_face.tab);
1516 	}
1517 
1518 	wattron(tabline, tab_face.background);
1519 	for (; x < (size_t)COLS; ++x)
1520 		waddch(tabline, ' ');
1521 	if (truncated)
1522 		mvwprintw(tabline, 0, COLS-1, ">");
1523 }
1524 
1525 static void
1526 redraw_window(WINDOW *win, int height, struct buffer *buffer)
1527 {
1528 	struct vline	*vl;
1529 	int		 l;
1530 
1531 	werase(win);
1532 
1533 	buffer->line_off = MIN(buffer->line_max-1, buffer->line_off);
1534 	if (TAILQ_EMPTY(&buffer->head))
1535 		return;
1536 
1537 	l = 0;
1538 	vl = nth_line(buffer, buffer->line_off);
1539 	for (; vl != NULL; vl = TAILQ_NEXT(vl, vlines)) {
1540 		wmove(win, l, x_offset);
1541 		print_vline(win, vl);
1542 		l++;
1543 		if (l == height)
1544 			break;
1545 	}
1546 
1547 	wmove(win, buffer->curs_y, buffer->curs_x);
1548 }
1549 
1550 static void
1551 redraw_help(void)
1552 {
1553 	redraw_window(help, help_lines, &helpwin);
1554 }
1555 
1556 static void
1557 redraw_body(struct tab *tab)
1558 {
1559 	redraw_window(body, body_lines, &tab->buffer);
1560 }
1561 
1562 static inline char
1563 trust_status_char(enum trust_state ts)
1564 {
1565 	switch (ts) {
1566 	case TS_UNKNOWN:	return 'u';
1567 	case TS_UNTRUSTED:	return '!';
1568 	case TS_TRUSTED:	return 'v';
1569 	case TS_VERIFIED:	return 'V';
1570 	}
1571 }
1572 
1573 static void
1574 redraw_modeline(struct tab *tab)
1575 {
1576 	double		 pct;
1577 	int		 x, y, max_x, max_y;
1578 	const char	*mode = tab->buffer.page.name;
1579 	const char	*spin = "-\\|/";
1580 
1581 	werase(modeline);
1582 	wattron(modeline, modeline_face.background);
1583 	wmove(modeline, 0, 0);
1584 
1585 	wprintw(modeline, "-%c%c %s ",
1586 	    spin[tab->loading_anim_step],
1587 	    trust_status_char(tab->trust),
1588 	    mode == NULL ? "(none)" : mode);
1589 
1590 	pct = (tab->buffer.line_off + tab->buffer.curs_y) * 100.0 / tab->buffer.line_max;
1591 
1592 	if (tab->buffer.line_max <= (size_t)body_lines)
1593                 wprintw(modeline, "All ");
1594 	else if (tab->buffer.line_off == 0)
1595                 wprintw(modeline, "Top ");
1596 	else if (tab->buffer.line_off + body_lines >= tab->buffer.line_max)
1597 		wprintw(modeline, "Bottom ");
1598 	else
1599 		wprintw(modeline, "%.0f%% ", pct);
1600 
1601 	wprintw(modeline, "%d/%d %s ",
1602 	    tab->buffer.line_off + tab->buffer.curs_y,
1603 	    tab->buffer.line_max,
1604 	    tab->hist_cur->h);
1605 
1606 	getyx(modeline, y, x);
1607 	getmaxyx(modeline, max_y, max_x);
1608 
1609 	(void)y;
1610 	(void)max_y;
1611 
1612 	for (; x < max_x; ++x)
1613 		waddstr(modeline, "-");
1614 
1615 	wattroff(modeline, modeline_face.background);
1616 }
1617 
1618 static void
1619 redraw_minibuffer(void)
1620 {
1621 	struct tab *tab;
1622 	size_t off_y, off_x = 0;
1623 	char *start, *c;
1624 
1625 	wattron(minibuf, minibuffer_face.background);
1626 	werase(minibuf);
1627 
1628 	if (in_minibuffer) {
1629 		mvwprintw(minibuf, 0, 0, "%s", ministate.prompt);
1630 		if (ministate.hist_cur != NULL)
1631 			wprintw(minibuf, "(%zu/%zu) ",
1632 			    ministate.hist_off + 1,
1633 			    ministate.history->len);
1634 
1635 		getyx(minibuf, off_y, off_x);
1636 
1637 		start = ministate.hist_cur != NULL
1638 			? ministate.hist_cur->h
1639 			: ministate.buf;
1640 		c = utf8_nth(ministate.buffer.current_line->line,
1641 		    ministate.buffer.cpoff);
1642 		while (utf8_swidth_between(start, c) > (size_t)COLS/2) {
1643 			start = utf8_next_cp(start);
1644 		}
1645 
1646 		waddstr(minibuf, start);
1647 	}
1648 
1649 	if (ministate.curmesg != NULL)
1650                 wprintw(minibuf, in_minibuffer ? "  [%s]" : "%s",
1651 		    ministate.curmesg);
1652 
1653 	if (!in_minibuffer && ministate.curmesg == NULL)
1654 		waddstr(minibuf, keybuf);
1655 
1656 	/* If nothing else, show the URL at point */
1657 	if (!in_minibuffer && ministate.curmesg == NULL && *keybuf == '\0') {
1658 		tab = current_tab();
1659 		if (tab->buffer.current_line != NULL &&
1660 		    tab->buffer.current_line->parent->type == LINE_LINK)
1661 			waddstr(minibuf, tab->buffer.current_line->parent->alt);
1662 	}
1663 
1664 	if (in_minibuffer)
1665 		wmove(minibuf, 0, off_x + utf8_swidth_between(start, c));
1666 
1667 	wattroff(minibuf, minibuffer_face.background);
1668 }
1669 
1670 static void
1671 redraw_tab(struct tab *tab)
1672 {
1673 	if (side_window) {
1674 		redraw_help();
1675 		wnoutrefresh(help);
1676 	}
1677 
1678 	restore_cursor(&tab->buffer);
1679 
1680 	redraw_tabline();
1681 	redraw_body(tab);
1682 	redraw_modeline(tab);
1683 	redraw_minibuffer();
1684 
1685 	wnoutrefresh(tabline);
1686 	wnoutrefresh(modeline);
1687 
1688 	if (in_minibuffer) {
1689 		wnoutrefresh(body);
1690 		wnoutrefresh(minibuf);
1691 	} else {
1692 		wnoutrefresh(minibuf);
1693 		wnoutrefresh(body);
1694 	}
1695 
1696 	doupdate();
1697 }
1698 
1699 static void
1700 emit_help_item(char *prfx, void *fn)
1701 {
1702 	struct line	*l;
1703 	struct cmds	*cmd;
1704 
1705 	for (cmd = cmds; cmd->cmd != NULL; ++cmd) {
1706 		if (fn == cmd->fn)
1707 			break;
1708 	}
1709 	assert(cmd != NULL);
1710 
1711 	if ((l = calloc(1, sizeof(*l))) == NULL)
1712 		abort();
1713 
1714 	l->type = LINE_TEXT;
1715 	l->alt = NULL;
1716 
1717 	asprintf(&l->line, "%s %s", prfx, cmd->cmd);
1718 
1719 	if (TAILQ_EMPTY(&helpwin.page.head))
1720 		TAILQ_INSERT_HEAD(&helpwin.page.head, l, lines);
1721 	else
1722 		TAILQ_INSERT_TAIL(&helpwin.page.head, l, lines);
1723 }
1724 
1725 static void
1726 rec_compute_help(struct kmap *keymap, char *prfx, size_t len)
1727 {
1728 	struct keymap	*k;
1729 	char		 p[32];
1730 	const char	*kn;
1731 
1732 	TAILQ_FOREACH(k, &keymap->m, keymaps) {
1733 		strlcpy(p, prfx, sizeof(p));
1734 		if (*p != '\0')
1735 			strlcat(p, " ", sizeof(p));
1736 		if (k->meta)
1737 			strlcat(p, "M-", sizeof(p));
1738 		if ((kn = unkbd(k->key)) != NULL)
1739 			strlcat(p, kn, sizeof(p));
1740 		else
1741 			strlcat(p, keyname(k->key), sizeof(p));
1742 
1743 		if (k->fn == NULL)
1744 			rec_compute_help(&k->map, p, sizeof(p));
1745 		else
1746 			emit_help_item(p, k->fn);
1747 	}
1748 }
1749 
1750 static void
1751 recompute_help(void)
1752 {
1753 	char	p[32] = { 0 };
1754 
1755 	empty_vlist(&helpwin);
1756 	empty_linelist(&helpwin);
1757 	rec_compute_help(current_map, p, sizeof(p));
1758 	wrap_page(&helpwin, help_cols);
1759 }
1760 
1761 static void
1762 vmessage(const char *fmt, va_list ap)
1763 {
1764 	if (evtimer_pending(&clminibufev, NULL))
1765 		evtimer_del(&clminibufev);
1766 	evtimer_set(&clminibufev, handle_clear_minibuf, NULL);
1767 	evtimer_add(&clminibufev, &clminibufev_timer);
1768 
1769 	free(ministate.curmesg);
1770 
1771 	/* TODO: what to do if the allocation fails here? */
1772 	if (vasprintf(&ministate.curmesg, fmt, ap) == -1)
1773 		ministate.curmesg = NULL;
1774 
1775 	redraw_minibuffer();
1776 	if (in_minibuffer) {
1777 		wrefresh(body);
1778 		wrefresh(minibuf);
1779 	} else {
1780 		wrefresh(minibuf);
1781 		wrefresh(body);
1782 	}
1783 }
1784 
1785 static void
1786 message(const char *fmt, ...)
1787 {
1788 	va_list ap;
1789 
1790 	va_start(ap, fmt);
1791 	vmessage(fmt, ap);
1792 	va_end(ap);
1793 }
1794 
1795 static void
1796 start_loading_anim(struct tab *tab)
1797 {
1798 	if (tab->loading_anim)
1799 		return;
1800 	tab->loading_anim = 1;
1801 	evtimer_set(&tab->loadingev, update_loading_anim, tab);
1802 	evtimer_add(&tab->loadingev, &loadingev_timer);
1803 }
1804 
1805 static void
1806 update_loading_anim(int fd, short ev, void *d)
1807 {
1808 	struct tab	*tab = d;
1809 
1810 	tab->loading_anim_step = (tab->loading_anim_step+1)%4;
1811 
1812 	if (tab->flags & TAB_CURRENT) {
1813 		redraw_modeline(tab);
1814 		wrefresh(modeline);
1815 		wrefresh(body);
1816 		if (in_minibuffer)
1817 			wrefresh(minibuf);
1818 	}
1819 
1820 	evtimer_add(&tab->loadingev, &loadingev_timer);
1821 }
1822 
1823 static void
1824 stop_loading_anim(struct tab *tab)
1825 {
1826 	if (!tab->loading_anim)
1827 		return;
1828 	evtimer_del(&tab->loadingev);
1829 	tab->loading_anim = 0;
1830 	tab->loading_anim_step = 0;
1831 
1832 	if (!(tab->flags & TAB_CURRENT))
1833 		return;
1834 
1835 	redraw_modeline(tab);
1836 
1837 	wrefresh(modeline);
1838 	wrefresh(body);
1839 	if (in_minibuffer)
1840 		wrefresh(minibuf);
1841 }
1842 
1843 static void
1844 load_url_in_tab(struct tab *tab, const char *url)
1845 {
1846 	message("Loading %s...", url);
1847 	start_loading_anim(tab);
1848 	load_url(tab, url);
1849 
1850 	tab->buffer.curs_x = 0;
1851 	tab->buffer.curs_y = 0;
1852 	redraw_tab(tab);
1853 }
1854 
1855 static void
1856 enter_minibuffer(void (*self_insert_fn)(void), void (*donefn)(void),
1857     void (*abortfn)(void), struct histhead *hist)
1858 {
1859 	in_minibuffer = 1;
1860 	base_map = &minibuffer_map;
1861 	current_map = &minibuffer_map;
1862 
1863 	base_map->unhandled_input = self_insert_fn;
1864 
1865 	ministate.donefn = donefn;
1866 	ministate.abortfn = abortfn;
1867 	memset(ministate.buf, 0, sizeof(ministate.buf));
1868 	ministate.buffer.current_line = &ministate.vline;
1869 	ministate.buffer.current_line->line = ministate.buf;
1870 	ministate.buffer.cpoff = 0;
1871 	strlcpy(ministate.buf, "", sizeof(ministate.prompt));
1872 
1873 	ministate.history = hist;
1874 	ministate.hist_cur = NULL;
1875 	ministate.hist_off = 0;
1876 }
1877 
1878 static void
1879 exit_minibuffer(void)
1880 {
1881 	werase(minibuf);
1882 
1883 	in_minibuffer = 0;
1884 	base_map = &global_map;
1885 	current_map = &global_map;
1886 }
1887 
1888 static void
1889 switch_to_tab(struct tab *tab)
1890 {
1891 	struct tab	*t;
1892 
1893 	TAILQ_FOREACH(t, &tabshead, tabs) {
1894 		t->flags &= ~TAB_CURRENT;
1895 	}
1896 
1897 	tab->flags |= TAB_CURRENT;
1898 	tab->flags &= ~TAB_URGENT;
1899 }
1900 
1901 unsigned int
1902 tab_new_id(void)
1903 {
1904 	return tab_counter++;
1905 }
1906 
1907 static struct tab *
1908 new_tab(const char *url)
1909 {
1910 	struct tab	*tab;
1911 
1912 	if ((tab = calloc(1, sizeof(*tab))) == NULL) {
1913 		event_loopbreak();
1914 		return NULL;
1915 	}
1916 	tab->fd = -1;
1917 
1918 	TAILQ_INIT(&tab->hist.head);
1919 
1920 	TAILQ_INIT(&tab->buffer.head);
1921 
1922 	tab->id = tab_new_id();
1923 	switch_to_tab(tab);
1924 
1925 	if (TAILQ_EMPTY(&tabshead))
1926 		TAILQ_INSERT_HEAD(&tabshead, tab, tabs);
1927 	else
1928 		TAILQ_INSERT_TAIL(&tabshead, tab, tabs);
1929 
1930 	load_url_in_tab(tab, url);
1931 	return tab;
1932 }
1933 
1934 static void
1935 session_new_tab_cb(const char *url)
1936 {
1937 	new_tab(url);
1938 }
1939 
1940 static void
1941 usage(void)
1942 {
1943 	fprintf(stderr, "USAGE: %s [-hn] [-c config] [url]\n", getprogname());
1944 	fprintf(stderr, "version: " PACKAGE " " VERSION "\n");
1945 }
1946 
1947 int
1948 ui_init(int argc, char * const *argv)
1949 {
1950 	char path[PATH_MAX];
1951 	const char *url = NEW_TAB_URL;
1952 	int ch, configtest = 0, fonf = 0;
1953 
1954 	strlcpy(path, getenv("HOME"), sizeof(path));
1955 	strlcat(path, "/.telescope/config", sizeof(path));
1956 
1957 	while ((ch = getopt(argc, argv, "c:hn")) != -1) {
1958 		switch (ch) {
1959 		case 'c':
1960 			fonf = 1;
1961 			strlcpy(path, optarg, sizeof(path));
1962 			break;
1963 		case 'n':
1964 			configtest = 1;
1965 			break;
1966 		case 'h':
1967 			usage();
1968 			return 0;
1969 		default:
1970 			usage();
1971 			return 1;
1972 		}
1973 	}
1974 	argc -= optind;
1975 	argv += optind;
1976 
1977 	parseconfig(path, fonf);
1978 	if (configtest){
1979 		puts("config OK");
1980 		exit(0);
1981 	}
1982 
1983 	if (argc != 0)
1984 		url = argv[0];
1985 
1986 	setlocale(LC_ALL, "");
1987 
1988 	TAILQ_INIT(&global_map.m);
1989 	global_map.unhandled_input = global_key_unbound;
1990 
1991 	TAILQ_INIT(&minibuffer_map.m);
1992 
1993 	TAILQ_INIT(&eecmd_history.head);
1994 	TAILQ_INIT(&ir_history.head);
1995 	TAILQ_INIT(&lu_history.head);
1996 
1997 	ministate.line.type = LINE_TEXT;
1998 	ministate.vline.parent = &ministate.line;
1999 	ministate.buffer.current_line = &ministate.vline;
2000 
2001 	/* initialize help window */
2002 	TAILQ_INIT(&helpwin.head);
2003 
2004 	base_map = &global_map;
2005 	current_map = &global_map;
2006 	load_default_keys();
2007 
2008 	initscr();
2009 	raw();
2010 	noecho();
2011 
2012 	nonl();
2013 	intrflush(stdscr, FALSE);
2014 
2015 	if ((tabline = newwin(1, COLS, 0, 0)) == NULL)
2016 		return 0;
2017 	if ((body = newwin(LINES - 3, COLS, 1, 0)) == NULL)
2018 		return 0;
2019 	if ((modeline = newwin(1, COLS, LINES-2, 0)) == NULL)
2020 		return 0;
2021 	if ((minibuf = newwin(1, COLS, LINES-1, 0)) == NULL)
2022 		return 0;
2023 	if ((help = newwin(1, 1, 1, 0)) == NULL)
2024 		return 0;
2025 
2026 	body_lines = LINES-3;
2027 	body_cols = COLS;
2028 
2029 	update_x_offset();
2030 
2031 	keypad(body, TRUE);
2032 	scrollok(body, TRUE);
2033 
2034 	/* non-blocking input */
2035 	wtimeout(body, 0);
2036 
2037 	mvwprintw(body, 0, 0, "");
2038 
2039 	event_set(&stdioev, 0, EV_READ | EV_PERSIST, dispatch_stdio, NULL);
2040 	event_add(&stdioev, NULL);
2041 
2042 	signal_set(&winchev, SIGWINCH, handle_resize, NULL);
2043 	signal_add(&winchev, NULL);
2044 
2045 	load_last_session(session_new_tab_cb);
2046 	if (strcmp(url, NEW_TAB_URL) || TAILQ_EMPTY(&tabshead))
2047 		new_tab(url);
2048 
2049 	return 1;
2050 }
2051 
2052 void
2053 ui_on_tab_loaded(struct tab *tab)
2054 {
2055 	stop_loading_anim(tab);
2056 	message("Loaded %s", tab->hist_cur->h);
2057 
2058 	redraw_tabline();
2059 	wrefresh(tabline);
2060 	if (in_minibuffer)
2061 		wrefresh(minibuf);
2062 	else
2063 		wrefresh(body);
2064 }
2065 
2066 void
2067 ui_on_tab_refresh(struct tab *tab)
2068 {
2069 	wrap_page(&tab->buffer, body_cols);
2070 	if (tab->flags & TAB_CURRENT) {
2071 		restore_cursor(&tab->buffer);
2072 		redraw_tab(tab);
2073 	} else
2074 		tab->flags |= TAB_URGENT;
2075 }
2076 
2077 void
2078 ui_require_input(struct tab *tab, int hide)
2079 {
2080 	/* TODO: hard-switching to another tab is ugly */
2081 	switch_to_tab(tab);
2082 
2083 	enter_minibuffer(ir_self_insert, ir_select, exit_minibuffer,
2084 	    &ir_history);
2085 	strlcpy(ministate.prompt, "Input required: ",
2086 	    sizeof(ministate.prompt));
2087 	redraw_tab(tab);
2088 }
2089 
2090 void
2091 ui_yornp(const char *prompt, void (*fn)(int, unsigned int),
2092     unsigned int data)
2093 {
2094 	size_t len;
2095 
2096 	if (in_minibuffer) {
2097 		fn(0, data);
2098 		return;
2099 	}
2100 
2101 	yornp_cb = fn;
2102 	yornp_data = data;
2103 	enter_minibuffer(yornp_self_insert, yornp_self_insert,
2104 	    yornp_abort, NULL);
2105 
2106 	len = sizeof(ministate.prompt);
2107 	strlcpy(ministate.prompt, prompt, len);
2108 	strlcat(ministate.prompt, " (y or n) ", len);
2109 	redraw_tab(current_tab());
2110 }
2111 
2112 void
2113 ui_read(const char *prompt, void (*fn)(const char*, unsigned int),
2114     unsigned int data)
2115 {
2116 	size_t len;
2117 
2118 	if (in_minibuffer)
2119 		return;
2120 
2121 	read_cb = fn;
2122 	read_data = data;
2123 	enter_minibuffer(read_self_insert, read_select, read_abort,
2124 	    &read_history);
2125 
2126 	len = sizeof(ministate.prompt);
2127 	strlcpy(ministate.prompt, prompt, len);
2128 	strlcat(ministate.prompt, ": ", len);
2129 	redraw_tab(current_tab());
2130 }
2131 
2132 void
2133 ui_notify(const char *fmt, ...)
2134 {
2135 	va_list ap;
2136 
2137 	va_start(ap, fmt);
2138 	vmessage(fmt, ap);
2139 	va_end(ap);
2140 }
2141 
2142 void
2143 ui_end(void)
2144 {
2145 	endwin();
2146 }