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 #include <limits.h>
18 #include <stdlib.h>
19 #include <string.h>
20 
21 #include "telescope.h"
22 
23 void
24 cmd_previous_line(struct buffer *buffer)
25 {
26 	struct vline	*vl;
27 
28 	if (buffer->current_line == NULL
29 	    || (vl = TAILQ_PREV(buffer->current_line, vhead, vlines)) == NULL)
30 		return;
31 
32 	if (--buffer->curs_y < 0) {
33 		buffer->curs_y = 0;
34 		cmd_scroll_line_up(buffer);
35 		return;
36 	}
37 
38 	buffer->current_line = vl;
39 	restore_cursor(buffer);
40 }
41 
42 void
43 cmd_next_line(struct buffer *buffer)
44 {
45 	struct vline	*vl;
46 
47 	if (buffer->current_line == NULL
48 	    || (vl = TAILQ_NEXT(buffer->current_line, vlines)) == NULL)
49 		return;
50 
51 	if (++buffer->curs_y > body_lines-1) {
52 		buffer->curs_y = body_lines-1;
53 		cmd_scroll_line_down(buffer);
54 		return;
55 	}
56 
57 	buffer->current_line = vl;
58 	restore_cursor(buffer);
59 }
60 
61 void
62 cmd_backward_char(struct buffer *buffer)
63 {
64 	if (buffer->cpoff != 0)
65 		buffer->cpoff--;
66 	restore_cursor(buffer);
67 }
68 
69 void
70 cmd_forward_char(struct buffer *buffer)
71 {
72 	size_t len = 0;
73 
74 	if (buffer->current_line->line != NULL)
75 		len = utf8_cplen(buffer->current_line->line);
76 	if (++buffer->cpoff > len)
77 		buffer->cpoff = len;
78 	restore_cursor(buffer);
79 }
80 
81 void
82 cmd_backward_paragraph(struct buffer *buffer)
83 {
84 	do {
85 		if (buffer->current_line == NULL ||
86 		    buffer->current_line == TAILQ_FIRST(&buffer->head)) {
87 			message("No previous paragraph");
88 			return;
89 		}
90 		cmd_previous_line(buffer);
91 	} while (buffer->current_line->line != NULL ||
92 	    buffer->current_line->parent->type != LINE_TEXT);
93 }
94 
95 void
96 cmd_forward_paragraph(struct buffer *buffer)
97 {
98 	do {
99 		if (buffer->current_line == NULL ||
100 		    buffer->current_line == TAILQ_LAST(&buffer->head, vhead)) {
101 			message("No next paragraph");
102 			return;
103 		}
104 		cmd_next_line(buffer);
105 	} while (buffer->current_line->line != NULL ||
106 	    buffer->current_line->parent->type != LINE_TEXT);
107 }
108 
109 void
110 cmd_move_beginning_of_line(struct buffer *buffer)
111 {
112 	buffer->cpoff = 0;
113 	restore_cursor(buffer);
114 }
115 
116 void
117 cmd_move_end_of_line(struct buffer *buffer)
118 {
119 	struct vline	*vl;
120 
121 	vl = buffer->current_line;
122 	if (vl->line == NULL)
123 		return;
124 	buffer->cpoff = utf8_cplen(vl->line);
125 	restore_cursor(buffer);
126 }
127 
128 void
129 cmd_redraw(struct buffer *buffer)
130 {
131         ui_schedule_redraw();
132 }
133 
134 void
135 cmd_scroll_line_up(struct buffer *buffer)
136 {
137 	if (buffer->current_line == NULL)
138 		return;
139 
140 	if (buffer->line_off == 0)
141 		return;
142 
143 	buffer->line_off--;
144 	buffer->top_line = TAILQ_PREV(buffer->top_line, vhead, vlines);
145 	buffer->current_line = TAILQ_PREV(buffer->current_line, vhead, vlines);
146 	restore_cursor(buffer);
147 }
148 
149 void
150 cmd_scroll_line_down(struct buffer *buffer)
151 {
152 	struct vline	*vl;
153 
154 	if (buffer->current_line == NULL)
155 		return;
156 
157 	if ((vl = TAILQ_NEXT(buffer->current_line, vlines)) == NULL)
158 		return;
159 
160 	buffer->current_line = vl;
161 
162 	buffer->top_line = TAILQ_NEXT(buffer->top_line, vlines);
163 	buffer->line_off++;
164 
165 	restore_cursor(buffer);
166 }
167 
168 void
169 cmd_scroll_up(struct buffer *buffer)
170 {
171 	size_t off;
172 
173 	off = body_lines-1;
174 
175 	for (; off > 0; --off)
176 		cmd_scroll_line_up(buffer);
177 }
178 
179 void
180 cmd_scroll_down(struct buffer *buffer)
181 {
182 	size_t off;
183 
184 	off = body_lines-1;
185 
186 	for (; off > 0; --off)
187 		cmd_scroll_line_down(buffer);
188 }
189 
190 void
191 cmd_beginning_of_buffer(struct buffer *buffer)
192 {
193 	buffer->current_line = TAILQ_FIRST(&buffer->head);
194 	buffer->top_line = buffer->current_line;
195 	buffer->line_off = 0;
196 	buffer->curs_y = 0;
197 	buffer->cpoff = 0;
198 	restore_cursor(buffer);
199 }
200 
201 void
202 cmd_end_of_buffer(struct buffer *buffer)
203 {
204 	ssize_t off;
205 
206 	off = buffer->line_max - body_lines;
207 	off = MAX(0, off);
208 
209 	while (buffer->line_off > (size_t)off) {
210 		buffer->line_off--;
211 		buffer->top_line = TAILQ_PREV(buffer->top_line, vhead, vlines);
212 	}
213 	while (buffer->line_off < (size_t)off) {
214 		buffer->line_off++;
215 		buffer->top_line = TAILQ_NEXT(buffer->top_line, vlines);
216 	}
217 
218 	buffer->line_off = off;
219 	buffer->curs_y = MIN((size_t)body_lines-1, buffer->line_max-1);
220 
221 	buffer->current_line = TAILQ_LAST(&buffer->head, vhead);
222 	buffer->cpoff = body_cols;
223 	restore_cursor(buffer);
224 }
225 
226 void
227 cmd_kill_telescope(struct buffer *buffer)
228 {
229 	save_session();
230 	event_loopbreak();
231 }
232 
233 void
234 cmd_push_button(struct buffer *buffer)
235 {
236 	struct vline	*vl;
237 
238 	vl = buffer->current_line;
239 	if (vl->parent->type != LINE_LINK)
240 		return;
241 
242 	load_url_in_tab(current_tab(), vl->parent->alt);
243 }
244 
245 void
246 cmd_push_button_new_tab(struct buffer *buffer)
247 {
248 	struct vline	*vl;
249 
250 	vl = buffer->current_line;
251 	if (vl->parent->type != LINE_LINK)
252 		return;
253 
254 	new_tab(vl->parent->alt);
255 }
256 
257 void
258 cmd_previous_button(struct buffer *buffer)
259 {
260 	struct excursion place;
261 
262 	save_excursion(&place, buffer);
263 
264 	do {
265 		if (buffer->current_line == NULL ||
266 		    buffer->current_line == TAILQ_FIRST(&buffer->head)) {
267 			restore_excursion(&place, buffer);
268 			message("No previous link");
269 			return;
270 		}
271 		cmd_previous_line(buffer);
272 	} while (buffer->current_line->parent->type != LINE_LINK);
273 }
274 
275 void
276 cmd_next_button(struct buffer *buffer)
277 {
278 	struct excursion place;
279 
280 	save_excursion(&place, buffer);
281 
282 	do {
283 		if (buffer->current_line == NULL ||
284 		    buffer->current_line == TAILQ_LAST(&buffer->head, vhead)) {
285 			restore_excursion(&place, buffer);
286 			message("No next link");
287 			return;
288 		}
289 		cmd_next_line(buffer);
290 	} while (buffer->current_line->parent->type != LINE_LINK);
291 }
292 
293 static inline int
294 is_heading(const struct line *l)
295 {
296 	return l->type == LINE_TITLE_1 ||
297 		l->type == LINE_TITLE_2 ||
298 		l->type == LINE_TITLE_3;
299 }
300 
301 void
302 cmd_previous_heading(struct buffer *buffer)
303 {
304 	struct excursion place;
305 
306 	save_excursion(&place, buffer);
307 
308 	do {
309 		if (buffer->current_line == NULL ||
310 		    buffer->current_line == TAILQ_FIRST(&buffer->head)) {
311 			restore_excursion(&place, buffer);
312 			message("No previous heading");
313 			return;
314 		}
315 		cmd_previous_line(buffer);
316 	} while (!is_heading(buffer->current_line->parent));
317 }
318 
319 void
320 cmd_next_heading(struct buffer *buffer)
321 {
322 	struct excursion place;
323 
324 	save_excursion(&place, buffer);
325 
326 	do {
327 		if (buffer->current_line == NULL ||
328 		    buffer->current_line == TAILQ_LAST(&buffer->head, vhead)) {
329 			restore_excursion(&place, buffer);
330 			message("No next heading");
331 			return;
332 		}
333 		cmd_next_line(buffer);
334 	} while (!is_heading(buffer->current_line->parent));
335 }
336 
337 void
338 cmd_previous_page(struct buffer *buffer)
339 {
340 	struct tab *tab = current_tab();
341 
342 	if (!load_previous_page(tab))
343 		message("No previous page");
344 	else
345 		start_loading_anim(tab);
346 }
347 
348 void
349 cmd_next_page(struct buffer *buffer)
350 {
351 	struct tab *tab = current_tab();
352 
353 	if (!load_next_page(tab))
354 		message("No next page");
355 	else
356 		start_loading_anim(tab);
357 }
358 
359 void
360 cmd_clear_minibuf(struct buffer *buffer)
361 {
362         message(NULL);
363 }
364 
365 void
366 cmd_execute_extended_command(struct buffer *buffer)
367 {
368 	size_t	 len;
369 
370 	if (in_minibuffer) {
371 		message("We don't have enable-recursive-minibuffers");
372 		return;
373 	}
374 
375 	enter_minibuffer(eecmd_self_insert, eecmd_select, exit_minibuffer,
376 	    &eecmd_history);
377 
378 	len = sizeof(ministate.prompt);
379 	strlcpy(ministate.prompt, "", len);
380 
381 	if (thiskey.meta)
382 		strlcat(ministate.prompt, "M-", len);
383 
384 	strlcat(ministate.prompt, ui_keyname(thiskey.key), len);
385 
386 	if (thiskey.meta)
387 		strlcat(ministate.prompt, " ", len);
388 }
389 
390 void
391 cmd_tab_close(struct buffer *buffer)
392 {
393 	struct tab *tab, *t;
394 
395 	tab = current_tab();
396 	if (TAILQ_PREV(tab, tabshead, tabs) == NULL &&
397 	    TAILQ_NEXT(tab, tabs) == NULL) {
398 		message("Can't close the only tab.");
399 		return;
400 	}
401 
402 	if (evtimer_pending(&tab->loadingev, NULL))
403 		evtimer_del(&tab->loadingev);
404 
405 	stop_tab(tab);
406 
407 	if ((t = TAILQ_PREV(tab, tabshead, tabs)) == NULL)
408 		t = TAILQ_NEXT(tab, tabs);
409 	TAILQ_REMOVE(&tabshead, tab, tabs);
410 	free(tab);
411 
412 	switch_to_tab(t);
413 }
414 
415 void
416 cmd_tab_close_other(struct buffer *buffer)
417 {
418 	struct tab *t, *i;
419 
420 	TAILQ_FOREACH_SAFE(t, &tabshead, tabs, i) {
421 		if (t->flags & TAB_CURRENT)
422 			continue;
423 
424 		stop_tab(t);
425 		TAILQ_REMOVE(&tabshead, t, tabs);
426 		free(t);
427 	}
428 }
429 
430 void
431 cmd_tab_new(struct buffer *buffer)
432 {
433 	const char *url;
434 
435 	if ((url = new_tab_url) == NULL)
436 		url = NEW_TAB_URL;
437 
438 	new_tab(url);
439 }
440 
441 void
442 cmd_tab_next(struct buffer *buffer)
443 {
444 	struct tab *tab, *t;
445 
446 	tab = current_tab();
447 	tab->flags &= ~TAB_CURRENT;
448 
449 	if ((t = TAILQ_NEXT(tab, tabs)) == NULL)
450 		t = TAILQ_FIRST(&tabshead);
451 	t->flags |= TAB_CURRENT;
452 	t->flags &= ~TAB_URGENT;
453 }
454 
455 void
456 cmd_tab_previous(struct buffer *buffer)
457 {
458 	struct tab *tab, *t;
459 
460 	tab = current_tab();
461 	tab->flags &= ~TAB_CURRENT;
462 
463 	if ((t = TAILQ_PREV(tab, tabshead, tabs)) == NULL)
464 		t = TAILQ_LAST(&tabshead, tabshead);
465 	t->flags |= TAB_CURRENT;
466 	t->flags &= ~TAB_URGENT;
467 }
468 
469 void
470 cmd_tab_move(struct buffer *buffer)
471 {
472 	struct tab *tab, *t;
473 
474 	tab = current_tab();
475 	t = TAILQ_NEXT(tab, tabs);
476 	TAILQ_REMOVE(&tabshead, tab, tabs);
477 
478 	if (t == NULL)
479 		TAILQ_INSERT_HEAD(&tabshead, tab, tabs);
480 	else
481 		TAILQ_INSERT_AFTER(&tabshead, t, tab, tabs);
482 }
483 
484 void
485 cmd_tab_move_to(struct buffer *buffer)
486 {
487 	struct tab *tab, *t;
488 
489 	tab = current_tab();
490 	t = TAILQ_PREV(tab, tabshead, tabs);
491 	TAILQ_REMOVE(&tabshead, tab, tabs);
492 
493 	if (t == NULL) {
494 		if (TAILQ_EMPTY(&tabshead))
495 			TAILQ_INSERT_HEAD(&tabshead, tab, tabs);
496 		else
497 			TAILQ_INSERT_TAIL(&tabshead, tab, tabs);
498 	} else
499 		TAILQ_INSERT_BEFORE(t, tab, tabs);
500 }
501 
502 void
503 cmd_load_url(struct buffer *buffer)
504 {
505 	if (in_minibuffer) {
506 		message("We don't have enable-recursive-minibuffers");
507 		return;
508 	}
509 
510 	enter_minibuffer(lu_self_insert, lu_select, exit_minibuffer,
511 	    &lu_history);
512 	strlcpy(ministate.prompt, "Load URL: ", sizeof(ministate.prompt));
513 	strlcpy(ministate.buf, "gemini://", sizeof(ministate.buf));
514 	cmd_move_end_of_line(&ministate.buffer);
515 }
516 
517 void
518 cmd_load_current_url(struct buffer *buffer)
519 {
520 	struct tab *tab = current_tab();
521 
522 	if (in_minibuffer) {
523 		message("We don't have enable-recursive-minibuffers");
524 		return;
525 	}
526 
527 	enter_minibuffer(lu_self_insert, lu_select, exit_minibuffer,
528 	    &lu_history);
529 	strlcpy(ministate.prompt, "Load URL: ", sizeof(ministate.prompt));
530 	strlcpy(ministate.buf, tab->hist_cur->h, sizeof(ministate.buf));
531 	ministate.buffer.cpoff = utf8_cplen(ministate.buf);
532 }
533 
534 void
535 cmd_bookmark_page(struct buffer *buffer)
536 {
537 	struct tab *tab = current_tab();
538 
539 	enter_minibuffer(lu_self_insert, bp_select, exit_minibuffer, NULL);
540 	strlcpy(ministate.prompt, "Bookmark URL: ", sizeof(ministate.prompt));
541 	strlcpy(ministate.buf, tab->hist_cur->h, sizeof(ministate.buf));
542 	ministate.buffer.cpoff = utf8_cplen(ministate.buf);
543 }
544 
545 void
546 cmd_list_bookmarks(struct buffer *buffer)
547 {
548 	load_url_in_tab(current_tab(), "about:bookmarks");
549 }
550 
551 void
552 cmd_toggle_help(struct buffer *buffer)
553 {
554 	ui_toggle_side_window();
555 }
556 
557 void
558 cmd_inc_fill_column(struct buffer *buffer)
559 {
560 	if (fill_column == INT_MAX)
561 		return;
562 
563 	fill_column += 2;
564 	message("fill-column: %d", fill_column);
565 
566 	ui_schedule_redraw();
567 }
568 
569 void
570 cmd_dec_fill_column(struct buffer *buffer)
571 {
572 	if (fill_column == INT_MAX || fill_column < 8)
573 		return;
574 
575 	fill_column -= 2;
576 	message("fill-column: %d", fill_column);
577 
578 	ui_schedule_redraw();
579 }
580 
581 void
582 cmd_olivetti_mode(struct buffer *buffer)
583 {
584 	olivetti_mode = !olivetti_mode;
585 	if (olivetti_mode)
586 		message("olivetti-mode enabled");
587 	else
588 		message("olivetti-mode disabled");
589 
590 	ui_schedule_redraw();
591 }
592 
593 void
594 cmd_mini_delete_char(struct buffer *buffer)
595 {
596 	char *c, *n;
597 
598 	if (!in_minibuffer) {
599 		message("text is read-only");
600 		return;
601 	}
602 
603 	minibuffer_taint_hist();
604 
605 	c = utf8_nth(buffer->current_line->line, buffer->cpoff);
606 	if (*c == '\0')
607 		return;
608 	n = utf8_next_cp(c);
609 
610 	memmove(c, n, strlen(n)+1);
611 }
612 
613 void
614 cmd_mini_delete_backward_char(struct buffer *buffer)
615 {
616 	char *c, *p, *start;
617 
618 	if (!in_minibuffer) {
619 		message("text is read-only");
620 		return;
621 	}
622 
623 	minibuffer_taint_hist();
624 
625 	c = utf8_nth(buffer->current_line->line, buffer->cpoff);
626 	start = buffer->current_line->line;
627 	if (c == start)
628 		return;
629 	p = utf8_prev_cp(c-1, start);
630 
631 	memmove(p, c, strlen(c)+1);
632 	buffer->cpoff--;
633 }
634 
635 void
636 cmd_mini_kill_line(struct buffer *buffer)
637 {
638 	char *c;
639 
640 	if (!in_minibuffer) {
641 		message("text is read-only");
642 		return;
643 	}
644 
645 	minibuffer_taint_hist();
646 	c = utf8_nth(buffer->current_line->line, buffer->cpoff);
647 	*c = '\0';
648 }
649 
650 void
651 cmd_mini_abort(struct buffer *buffer)
652 {
653 	if (!in_minibuffer)
654 		return;
655 
656 	ministate.abortfn();
657 }
658 
659 void
660 cmd_mini_complete_and_exit(struct buffer *buffer)
661 {
662 	if (!in_minibuffer)
663 		return;
664 
665 	minibuffer_taint_hist();
666 	ministate.donefn();
667 }
668 
669 void
670 cmd_mini_previous_history_element(struct buffer *buffer)
671 {
672 	if (ministate.history == NULL) {
673 		message("No history");
674 		return;
675 	}
676 
677 	if (ministate.hist_cur == NULL ||
678 	    (ministate.hist_cur = TAILQ_PREV(ministate.hist_cur, mhisthead, entries)) == NULL) {
679 		ministate.hist_cur = TAILQ_LAST(&ministate.history->head, mhisthead);
680 		ministate.hist_off = ministate.history->len - 1;
681 		if (ministate.hist_cur == NULL)
682 			message("No prev item");
683 	} else {
684 		ministate.hist_off--;
685 	}
686 
687 	if (ministate.hist_cur != NULL)
688 		buffer->current_line->line = ministate.hist_cur->h;
689 }
690 
691 void
692 cmd_mini_next_history_element(struct buffer *buffer)
693 {
694 	if (ministate.history == NULL) {
695 		message("No history");
696 		return;
697 	}
698 
699 	if (ministate.hist_cur == NULL ||
700 	    (ministate.hist_cur = TAILQ_NEXT(ministate.hist_cur, entries)) == NULL) {
701 		ministate.hist_cur = TAILQ_FIRST(&ministate.history->head);
702 		ministate.hist_off = 0;
703 		if (ministate.hist_cur == NULL)
704 			message("No next item");
705 	} else {
706 		ministate.hist_off++;
707 	}
708 
709 	if (ministate.hist_cur != NULL)
710 		buffer->current_line->line = ministate.hist_cur->h;
711 }