Merge branch 'maint'
[paraslash.git] / mood.c
1 /*
2 * Copyright (C) 2007 Andre Noll <maan@tuebingen.mpg.de>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file mood.c Paraslash's mood handling functions. */
8
9 #include <regex.h>
10 #include <osl.h>
11 #include <lopsub.h>
12
13 #include "para.h"
14 #include "error.h"
15 #include "string.h"
16 #include "afh.h"
17 #include "afs.h"
18 #include "list.h"
19 #include "ipc.h"
20 #include "mm.h"
21 #include "sideband.h"
22 #include "mood.h"
23 #include "sched.h"
24
25 /**
26 * Contains statistical data of the currently admissible audio files.
27 *
28 * It is used to assign normalized score values to each admissible audio file.
29 */
30 struct afs_statistics {
31 /** Sum of num played over all admissible files. */
32 int64_t num_played_sum;
33 /** Sum of last played times over all admissible files. */
34 int64_t last_played_sum;
35 /** Quadratic deviation of num played count. */
36 int64_t num_played_qd;
37 /** Quadratic deviation of last played time. */
38 int64_t last_played_qd;
39 /** Number of admissible files */
40 unsigned num;
41 };
42 static struct afs_statistics statistics;
43
44 /**
45 * Each line of the current mood corresponds to a mood_item.
46 */
47 struct mood_item {
48 /** The method this line is referring to. */
49 const struct mood_method *method;
50 /** The data structure computed by the mood parser. */
51 void *parser_data;
52 /** The given score value, or zero if none was given. */
53 int32_t score_arg;
54 /** Non-zero if random scoring was requested. */
55 int random_score;
56 /** Whether the "not" keyword was given in the mood line. */
57 int logical_not;
58 /** The position in the list of items. */
59 struct list_head mood_item_node;
60 };
61
62 /**
63 * Created from the mood definition by mood_open().
64 *
65 * When a mood is opened, each line of its definition is investigated, and a
66 * corresponding mood item is produced. Each mood line starts with \p accept,
67 * \p deny, or \p score which determines the type of the mood line. For each
68 * such type a linked list is maintained whose entries are the mood items.
69 *
70 * \sa mood_item, mood_open().
71 */
72 struct mood {
73 /** The name of this mood. */
74 char *name;
75 /** The list of mood items of type \p accept. */
76 struct list_head accept_list;
77 /** The list of mood items of type \p deny. */
78 struct list_head deny_list;
79 /** The list of mood items of type \p score. */
80 struct list_head score_list;
81 };
82
83 /*
84 * If current_mood is NULL then no mood is currently open. If
85 * current_mood->name is NULL, the dummy mood is currently open
86 */
87 static struct mood *current_mood;
88
89 /**
90 * Rough approximation to sqrt.
91 *
92 * \param x Integer of which to calculate the sqrt.
93 *
94 * \return An integer res with res * res <= x.
95 */
96 __a_const static uint64_t int_sqrt(uint64_t x)
97 {
98 uint64_t op, res, one = 1;
99 op = x;
100 res = 0;
101
102 one = one << 62;
103 while (one > op)
104 one >>= 2;
105
106 while (one != 0) {
107 if (op >= res + one) {
108 op = op - (res + one);
109 res = res + 2 * one;
110 }
111 res /= 2;
112 one /= 4;
113 }
114 // PARA_NOTICE_LOG("sqrt(%llu) = %llu\n", x, res);
115 return res;
116 }
117
118 /*
119 * Returns true if row matches, false if it does not match. In any case score
120 * and score_arg_sum are set/increased accordingly.
121 */
122 static bool get_item_score(struct mood_item *item, const struct afs_info *afsi,
123 const struct afh_info *afhi, const char *path, long *score,
124 long *score_arg_sum)
125 {
126 int ret;
127 bool match = true;
128
129 *score_arg_sum += item->random_score? 100 : PARA_ABS(item->score_arg);
130 ret = 100;
131 if (item->method) {
132 ret = item->method->score_function(path, afsi, afhi,
133 item->parser_data);
134 if ((ret < 0 && !item->logical_not) || (ret >= 0 && item->logical_not))
135 match = false;
136 }
137 if (item->random_score)
138 *score = PARA_ABS(ret) * para_random(100);
139 else
140 *score = PARA_ABS(ret) * item->score_arg;
141 return match;
142 }
143
144 /* returns 1 if row admissible, 0 if not, negative on errors */
145 static int compute_mood_score(const struct osl_row *aft_row, struct mood *m,
146 long *result)
147 {
148 struct mood_item *item;
149 int ret;
150 bool match;
151 long score_arg_sum = 0, score = 0, item_score;
152 struct afs_info afsi;
153 struct afh_info afhi;
154 char *path;
155
156 if (!m)
157 return -E_NO_MOOD;
158 ret = get_afsi_of_row(aft_row, &afsi);
159 if (ret< 0)
160 return ret;
161 ret = get_afhi_of_row(aft_row, &afhi);
162 if (ret< 0)
163 return ret;
164 ret = get_audio_file_path_of_row(aft_row, &path);
165 if (ret< 0)
166 return ret;
167 /* reject audio file if it matches any entry in the deny list */
168 list_for_each_entry(item, &m->deny_list, mood_item_node) {
169 match = get_item_score(item, &afsi, &afhi, path, &item_score,
170 &score_arg_sum);
171 if (match) /* not admissible */
172 return 0;
173 score += item_score;
174 }
175 match = false;
176 list_for_each_entry(item, &m->accept_list, mood_item_node) {
177 ret = get_item_score(item, &afsi, &afhi, path, &item_score,
178 &score_arg_sum);
179 if (ret == 0)
180 continue;
181 match = true;
182 score += item_score;
183 }
184 /* reject if there is no matching entry in the accept list */
185 if (!match && !list_empty(&m->accept_list))
186 return 0;
187 list_for_each_entry(item, &m->score_list, mood_item_node) {
188 match = get_item_score(item, &afsi, &afhi, path, &item_score,
189 &score_arg_sum);
190 if (match)
191 score += item_score;
192 }
193 if (score_arg_sum)
194 score /= score_arg_sum;
195 *result = score;
196 return 1;
197 }
198
199 static void cleanup_list_entry(struct mood_item *item)
200 {
201 if (item->method && item->method->cleanup)
202 item->method->cleanup(item->parser_data);
203 else
204 free(item->parser_data);
205 list_del(&item->mood_item_node);
206 free(item);
207 }
208
209 static void destroy_mood(struct mood *m)
210 {
211 struct mood_item *tmp, *item;
212
213 if (!m)
214 return;
215 list_for_each_entry_safe(item, tmp, &m->accept_list, mood_item_node)
216 cleanup_list_entry(item);
217 list_for_each_entry_safe(item, tmp, &m->deny_list, mood_item_node)
218 cleanup_list_entry(item);
219 list_for_each_entry_safe(item, tmp, &m->score_list, mood_item_node)
220 cleanup_list_entry(item);
221 free(m->name);
222 free(m);
223 }
224
225 static struct mood *alloc_new_mood(const char *name)
226 {
227 struct mood *m = para_calloc(sizeof(struct mood));
228 if (name)
229 m->name = para_strdup(name);
230 INIT_LIST_HEAD(&m->accept_list);
231 INIT_LIST_HEAD(&m->deny_list);
232 INIT_LIST_HEAD(&m->score_list);
233 return m;
234 }
235
236 /** The different types of a mood line. */
237 enum mood_line_type {
238 /** Invalid. */
239 ML_INVALID,
240 /** Accept line. */
241 ML_ACCEPT,
242 /** Deny line. */
243 ML_DENY,
244 /** Score line. */
245 ML_SCORE
246 };
247
248 /** Data passed to the parser of a mood line. */
249 struct mood_line_parser_data {
250 /** The mood this mood line belongs to. */
251 struct mood *m;
252 /** The line number in the mood definition. */
253 unsigned line_num;
254 };
255
256 /*
257 * <accept [with score <score>] | deny [with score <score>] | score <score>>
258 * [if] [not] <mood_method> [options]
259 * <score> is either an integer or "random" which assigns a random score to
260 * all matching files
261 */
262
263 static int parse_mood_line(char *mood_line, void *data)
264 {
265 struct mood_line_parser_data *mlpd = data;
266 char **argv;
267 unsigned num_words;
268 char **w;
269 int i, ret;
270 enum mood_line_type mlt = ML_INVALID;
271 struct mood_item *mi = NULL;
272
273 mlpd->line_num++;
274 ret = create_argv(mood_line, " \t", &argv);
275 if (ret < 0)
276 return ret;
277 num_words = ret;
278 if (!num_words) /* empty line */
279 goto out;
280 w = argv;
281 if (**w == '#') /* comment */
282 goto out;
283 if (!strcmp(*w, "accept"))
284 mlt = ML_ACCEPT;
285 else if (!strcmp(*w, "deny"))
286 mlt = ML_DENY;
287 else if (!strcmp(*w, "score"))
288 mlt = ML_SCORE;
289 ret = -E_MOOD_SYNTAX;
290 if (mlt == ML_INVALID)
291 goto out;
292 mi = para_calloc(sizeof(struct mood_item));
293 if (mlt != ML_SCORE) {
294 ret = -E_MOOD_SYNTAX;
295 w++;
296 if (!*w)
297 goto out;
298 if (strcmp(*w, "with"))
299 goto check_for_if;
300 w++;
301 if (!*w)
302 goto out;
303 if (strcmp(*w, "score"))
304 goto out;
305 }
306 if (mlt == ML_SCORE || !strcmp(*w, "score")) {
307 ret = -E_MOOD_SYNTAX;
308 w++;
309 if (!*w)
310 goto out;
311 if (strcmp(*w, "random")) {
312 mi->random_score = 0;
313 ret = para_atoi32(*w, &mi->score_arg);
314 if (ret < 0)
315 goto out;
316 } else {
317 mi->random_score = 1;
318 if (!*(w + 1))
319 goto success; /* the line "score random" is valid */
320 }
321 } else
322 mi->score_arg = 0;
323 ret = -E_MOOD_SYNTAX;
324 w++;
325 if (!*w)
326 goto out;
327 check_for_if:
328 if (!strcmp(*w, "if")) {
329 ret = -E_MOOD_SYNTAX;
330 w++;
331 if (!*w)
332 goto out;
333 }
334 if (!strcmp(*w, "not")) {
335 ret = -E_MOOD_SYNTAX;
336 w++;
337 if (!*w)
338 goto out;
339 mi->logical_not = 1;
340 } else
341 mi->logical_not = 0;
342 for (i = 0; mood_methods[i].parser; i++) {
343 if (strcmp(*w, mood_methods[i].name))
344 continue;
345 break;
346 }
347 ret = -E_MOOD_SYNTAX;
348 if (!mood_methods[i].parser)
349 goto out;
350 ret = mood_methods[i].parser(num_words - 1 - (w - argv), w,
351 &mi->parser_data);
352 if (ret < 0)
353 goto out;
354 mi->method = &mood_methods[i];
355 success:
356 if (mlpd->m) {
357 if (mlt == ML_ACCEPT)
358 para_list_add(&mi->mood_item_node, &mlpd->m->accept_list);
359 else if (mlt == ML_DENY)
360 para_list_add(&mi->mood_item_node, &mlpd->m->deny_list);
361 else
362 para_list_add(&mi->mood_item_node, &mlpd->m->score_list);
363 }
364 PARA_DEBUG_LOG("%s entry added, method: %p\n", mlt == ML_ACCEPT? "accept" :
365 (mlt == ML_DENY? "deny" : "score"), mi->method);
366 ret = 1;
367 out:
368 free_argv(argv);
369 if (ret >= 0)
370 return ret;
371 if (mi) {
372 free(mi->parser_data);
373 free(mi);
374 }
375 return ret;
376 }
377
378 static int load_mood(const struct osl_row *mood_row, struct mood **m)
379 {
380 char *mood_name;
381 struct osl_object mood_def;
382 struct mood_line_parser_data mlpd = {.line_num = 0};
383 int ret;
384
385 *m = NULL;
386 ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
387 if (ret < 0)
388 return ret;
389 if (!*mood_name)
390 return -E_DUMMY_ROW;
391 mlpd.m = alloc_new_mood(mood_name);
392 ret = for_each_line(FELF_READ_ONLY, mood_def.data, mood_def.size,
393 parse_mood_line, &mlpd);
394 osl_close_disk_object(&mood_def);
395 if (ret < 0) {
396 PARA_ERROR_LOG("unable to load mood %s: %s\n", mlpd.m->name,
397 para_strerror(-ret));
398 destroy_mood(mlpd.m);
399 return ret;
400 }
401 *m = mlpd.m;
402 return 1;
403 }
404
405 static int check_mood(struct osl_row *mood_row, void *data)
406 {
407 struct para_buffer *pb = data;
408 char *mood_name;
409 struct osl_object mood_def;
410 struct mood_line_parser_data mlpd = {.line_num = 0};
411
412 int ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
413
414 if (ret < 0) {
415 para_printf(pb, "cannot read mood\n");
416 return ret;
417 }
418 if (!*mood_name) /* ignore dummy row */
419 goto out;
420 para_printf(pb, "checking mood %s...\n", mood_name);
421 ret = for_each_line(FELF_READ_ONLY, mood_def.data, mood_def.size,
422 parse_mood_line, &mlpd);
423 if (ret < 0)
424 para_printf(pb, "mood %s: error in line %u: %s\n", mood_name,
425 mlpd.line_num, para_strerror(-ret));
426 ret = 1; /* don't fail the loop on invalid mood definitions */
427 out:
428 osl_close_disk_object(&mood_def);
429 return ret;
430 }
431
432 /**
433 * Check all moods for syntax errors.
434 *
435 * \param aca Only ->pbout is used for diagnostics.
436 *
437 * \return Negative on fatal errors. Inconsistent mood definitions are not
438 * considered an error.
439 */
440 int mood_check_callback(struct afs_callback_arg *aca)
441 {
442 para_printf(&aca->pbout, "checking moods...\n");
443 return osl(osl_rbtree_loop(moods_table, BLOBCOL_ID, &aca->pbout,
444 check_mood));
445 }
446
447 static int64_t normalized_value(int64_t x, int64_t n, int64_t sum, int64_t qd)
448 {
449 if (!n || !qd)
450 return 0;
451 return 100 * (n * x - sum) / (int64_t)int_sqrt(n) / (int64_t)int_sqrt(qd);
452 }
453
454 static long compute_score(struct afs_info *afsi, long mood_score)
455 {
456 mood_score -= normalized_value(afsi->num_played, statistics.num,
457 statistics.num_played_sum, statistics.num_played_qd);
458 mood_score -= normalized_value(afsi->last_played, statistics.num,
459 statistics.last_played_sum, statistics.last_played_qd);
460 return mood_score / 3;
461 }
462
463 static int add_afs_statistics(const struct osl_row *row)
464 {
465 uint64_t n, x, s, q;
466 struct afs_info afsi;
467 int ret;
468
469 ret = get_afsi_of_row(row, &afsi);
470 if (ret < 0)
471 return ret;
472 n = statistics.num;
473 x = afsi.last_played;
474 s = statistics.last_played_sum;
475 if (n > 0) {
476 q = (x > s / n)? x - s / n : s / n - x;
477 statistics.last_played_qd += q * q * n / (n + 1);
478 }
479 statistics.last_played_sum += x;
480
481 x = afsi.num_played;
482 s = statistics.num_played_sum;
483 if (n > 0) {
484 q = (x > s / n)? x - s / n : s / n - x;
485 statistics.num_played_qd += q * q * n / (n + 1);
486 }
487 statistics.num_played_sum += x;
488 statistics.num++;
489 return 1;
490 }
491
492 static int del_afs_statistics(const struct osl_row *row)
493 {
494 uint64_t n, s, q, a, new_s;
495 struct afs_info afsi;
496 int ret;
497 ret = get_afsi_of_row(row, &afsi);
498 if (ret < 0)
499 return ret;
500 n = statistics.num;
501 assert(n);
502 if (n == 1) {
503 memset(&statistics, 0, sizeof(statistics));
504 return 1;
505 }
506
507 s = statistics.last_played_sum;
508 q = statistics.last_played_qd;
509 a = afsi.last_played;
510 new_s = s - a;
511 statistics.last_played_sum = new_s;
512 statistics.last_played_qd = q + s * s / n - a * a
513 - new_s * new_s / (n - 1);
514
515 s = statistics.num_played_sum;
516 q = statistics.num_played_qd;
517 a = afsi.num_played;
518 new_s = s - a;
519 statistics.num_played_sum = new_s;
520 statistics.num_played_qd = q + s * s / n - a * a
521 - new_s * new_s / (n - 1);
522
523 statistics.num--;
524 return 1;
525 }
526
527 /**
528 * Structure used during mood_open().
529 *
530 * At mood open time we determine the set of admissible files for the given
531 * mood. The mood score of each admissible file is computed by adding up all
532 * mood item scores. Next, we update the afs statistics and append a struct
533 * admissible_file_info to a temporary array.
534 *
535 * When all files have been processed in this way, the final score of each
536 * admissible file is computed by adding the dynamic score (which depends on
537 * the afs_statistics and the current time) to the mood score. Finally, all
538 * audio files in the temporary array are added to the score table and the
539 * array is freed.
540 *
541 * \sa mood_method, admissible_array.
542 */
543 struct admissible_file_info
544 {
545 /** The admissible audio file. */
546 struct osl_row *aft_row;
547 /** Its score. */
548 long score;
549 };
550
551 /** The temporary array of admissible files. */
552 struct admissible_array {
553 /** Files are admissible wrt. this mood. */
554 struct mood *m;
555 /** The size of the array */
556 unsigned size;
557 /** Pointer to the array of admissible files. */
558 struct admissible_file_info *array;
559 };
560
561 /**
562 * Add an entry to the array of admissible files.
563 *
564 * \param aft_row The audio file to be added.
565 * \param private_data Pointer to a struct admissible_file_info.
566 *
567 * \return 1 if row admissible, 0 if not, negative on errors.
568 */
569 static int add_if_admissible(struct osl_row *aft_row, void *data)
570 {
571 struct admissible_array *aa = data;
572 int ret;
573 long score = 0;
574
575 ret = compute_mood_score(aft_row, aa->m, &score);
576 if (ret <= 0)
577 return ret;
578 if (statistics.num >= aa->size) {
579 aa->size *= 2;
580 aa->size += 100;
581 aa->array = para_realloc(aa->array,
582 aa->size * sizeof(struct admissible_file_info));
583 }
584 aa->array[statistics.num].aft_row = aft_row;
585 aa->array[statistics.num].score = score;
586 ret = add_afs_statistics(aft_row);
587 if (ret < 0)
588 return ret;
589 return 1;
590 }
591
592 /**
593 * Compute the new quadratic deviation in case one element changes.
594 *
595 * \param n Number of elements.
596 * \param old_qd The quadratic deviation before the change.
597 * \param old_val The value that was replaced.
598 * \param new_val The replacement value.
599 * \param old_sum The sum of all elements before the update.
600 *
601 * \return The new quadratic deviation resulting from replacing old_val
602 * by new_val.
603 *
604 * Given n real numbers a_1, ..., a_n, their sum S = a_1 + ... + a_n,
605 * their quadratic deviation
606 *
607 * q = (a_1 - S/n)^2 + ... + (a_n - S/n)^2,
608 *
609 * and a real number b, the quadratic deviation q' of a_1,...a_{n-1}, b (ie.
610 * the last number a_n was replaced by b) may be computed in O(1) time in terms
611 * of n, q, a_n, b, and S as
612 *
613 * q' = q + d * s - (2 * S + d) * d / n
614 * = q + d * (s - 2 * S / n - d /n),
615 *
616 * where d = b - a_n, and s = b + a_n.
617 *
618 * Example: n = 3, a_1 = 3, a_2 = 5, a_3 = 7, b = 10. Then S = 15, q = 8, d = 3,
619 * s = 17, so
620 *
621 * q + d * s - (2 * S + d) * d / n = 8 + 51 - 33 = 26,
622 *
623 * which equals q' = (3 - 6)^2 + (5 - 6)^2 + (10 - 6)^2.
624 *
625 */
626 _static_inline_ int64_t update_quadratic_deviation(int64_t n, int64_t old_qd,
627 int64_t old_val, int64_t new_val, int64_t old_sum)
628 {
629 int64_t delta = new_val - old_val;
630 int64_t sigma = new_val + old_val;
631 return old_qd + delta * (sigma - 2 * old_sum / n - delta / n);
632 }
633
634 static int update_afs_statistics(struct afs_info *old_afsi, struct afs_info *new_afsi)
635 {
636 unsigned n;
637 int ret = get_num_admissible_files(&n);
638
639 if (ret < 0)
640 return ret;
641 assert(n);
642
643 statistics.last_played_qd = update_quadratic_deviation(n,
644 statistics.last_played_qd, old_afsi->last_played,
645 new_afsi->last_played, statistics.last_played_sum);
646 statistics.last_played_sum += new_afsi->last_played - old_afsi->last_played;
647
648 statistics.num_played_qd = update_quadratic_deviation(n,
649 statistics.num_played_qd, old_afsi->num_played,
650 new_afsi->num_played, statistics.num_played_sum);
651 statistics.num_played_sum += new_afsi->num_played - old_afsi->num_played;
652 return 1;
653 }
654
655 static int add_to_score_table(const struct osl_row *aft_row, long mood_score)
656 {
657 long score;
658 struct afs_info afsi;
659 int ret = get_afsi_of_row(aft_row, &afsi);
660
661 if (ret < 0)
662 return ret;
663 score = compute_score(&afsi, mood_score);
664 return score_add(aft_row, score);
665 }
666
667 static int delete_from_statistics_and_score_table(const struct osl_row *aft_row)
668 {
669 int ret = del_afs_statistics(aft_row);
670 if (ret < 0)
671 return ret;
672 return score_delete(aft_row);
673 }
674
675 /**
676 * Delete one entry from the statistics and from the score table.
677 *
678 * \param aft_row The audio file which is no longer admissible.
679 *
680 * \return Positive on success, negative on errors.
681 *
682 * \sa score_delete().
683 */
684 static int mood_delete_audio_file(const struct osl_row *aft_row)
685 {
686 int ret;
687
688 ret = row_belongs_to_score_table(aft_row, NULL);
689 if (ret < 0)
690 return ret;
691 if (!ret) /* not admissible, nothing to do */
692 return 1;
693 return delete_from_statistics_and_score_table(aft_row);
694 }
695
696 /**
697 * Compute the new score of an audio file wrt. the current mood.
698 *
699 * \param aft_row Determines the audio file.
700 * \param old_afsi The audio file selector info before updating.
701 *
702 * The \a old_afsi argument may be \p NULL which indicates that no changes to
703 * the audio file info were made.
704 *
705 * \return Positive on success, negative on errors.
706 */
707 static int mood_update_audio_file(const struct osl_row *aft_row,
708 struct afs_info *old_afsi)
709 {
710 long score, percent;
711 int ret, is_admissible, was_admissible = 0;
712 struct afs_info afsi;
713 unsigned rank;
714
715 if (!current_mood)
716 return 1; /* nothing to do */
717 ret = row_belongs_to_score_table(aft_row, &rank);
718 if (ret < 0)
719 return ret;
720 was_admissible = ret;
721 ret = compute_mood_score(aft_row, current_mood, &score);
722 if (ret < 0)
723 return ret;
724 is_admissible = (ret > 0);
725 if (!was_admissible && !is_admissible)
726 return 1;
727 if (was_admissible && !is_admissible)
728 return delete_from_statistics_and_score_table(aft_row);
729 if (!was_admissible && is_admissible) {
730 ret = add_afs_statistics(aft_row);
731 if (ret < 0)
732 return ret;
733 return add_to_score_table(aft_row, score);
734 }
735 /* update score */
736 ret = get_afsi_of_row(aft_row, &afsi);
737 if (ret < 0)
738 return ret;
739 if (old_afsi) {
740 ret = update_afs_statistics(old_afsi, &afsi);
741 if (ret < 0)
742 return ret;
743 }
744 score = compute_score(&afsi, score);
745 PARA_DEBUG_LOG("score: %li\n", score);
746 percent = (score + 100) / 3;
747 if (percent > 100)
748 percent = 100;
749 else if (percent < 0)
750 percent = 0;
751 PARA_DEBUG_LOG("moving from rank %u to %li%%\n", rank, percent);
752 return score_update(aft_row, percent);
753 }
754
755 static void log_statistics(void)
756 {
757 unsigned n = statistics.num;
758 int mean_days, sigma_days;
759 /*
760 * We can not use the "now" pointer from sched.c here because we are
761 * called before schedule(), which initializes "now".
762 */
763 struct timeval rnow;
764
765 assert(current_mood);
766 PARA_NOTICE_LOG("loaded mood %s\n", current_mood->name?
767 current_mood->name : "(dummy)");
768 if (!n) {
769 PARA_WARNING_LOG("no admissible files\n");
770 return;
771 }
772 PARA_NOTICE_LOG("%u admissible files\n", statistics.num);
773 clock_get_realtime(&rnow);
774 mean_days = (rnow.tv_sec - statistics.last_played_sum / n) / 3600 / 24;
775 sigma_days = int_sqrt(statistics.last_played_qd / n) / 3600 / 24;
776 PARA_NOTICE_LOG("last_played mean/sigma: %d/%d days\n", mean_days, sigma_days);
777 PARA_NOTICE_LOG("num_played mean/sigma: %llu/%llu\n",
778 (long long unsigned)statistics.num_played_sum / n,
779 (long long unsigned)int_sqrt(statistics.num_played_qd / n));
780 }
781
782 /**
783 * Close the current mood.
784 *
785 * Free all resources of the current mood which were allocated during
786 * mood_open().
787 */
788 void close_current_mood(void)
789 {
790 destroy_mood(current_mood);
791 current_mood = NULL;
792 memset(&statistics, 0, sizeof(statistics));
793 }
794
795 /**
796 * Change the current mood.
797 *
798 * \param mood_name The name of the mood to open.
799 *
800 * If \a mood_name is \a NULL, load the dummy mood that accepts every audio file
801 * and uses a scoring method based only on the \a last_played information.
802 *
803 * If there is already an open mood, it will be closed first.
804 *
805 * \return Positive on success, negative on errors. Loading the dummy mood
806 * always succeeds.
807 *
808 * \sa struct admissible_file_info, struct admissible_array, struct
809 * afs_info::last_played, mood_close().
810 */
811 int change_current_mood(const char *mood_name)
812 {
813 int i, ret;
814 struct admissible_array aa = {
815 .size = 0,
816 .array = NULL
817 };
818
819 if (mood_name) {
820 struct mood *m;
821 struct osl_row *row;
822 struct osl_object obj = {
823 .data = (char *)mood_name,
824 .size = strlen(mood_name) + 1
825 };
826 ret = osl(osl_get_row(moods_table, BLOBCOL_NAME, &obj, &row));
827 if (ret < 0) {
828 PARA_NOTICE_LOG("no such mood: %s\n", mood_name);
829 return ret;
830 }
831 ret = load_mood(row, &m);
832 if (ret < 0)
833 return ret;
834 close_current_mood();
835 current_mood = m;
836 } else { /* load dummy mood */
837 close_current_mood();
838 current_mood = alloc_new_mood(NULL);
839 }
840 aa.m = current_mood;
841 PARA_NOTICE_LOG("computing statistics of admissible files\n");
842 ret = audio_file_loop(&aa, add_if_admissible);
843 if (ret < 0)
844 return ret;
845 for (i = 0; i < statistics.num; i++) {
846 struct admissible_file_info *a = aa.array + i;
847 ret = add_to_score_table(a->aft_row, a->score);
848 if (ret < 0)
849 goto out;
850 }
851 log_statistics();
852 ret = statistics.num;
853 out:
854 free(aa.array);
855 return ret;
856 }
857 /**
858 * Close and re-open the current mood.
859 *
860 * This function is used if changes to the audio file table or the
861 * attribute table were made that render the current list of admissible
862 * files useless. For example, if an attribute is removed from the
863 * attribute table, this function is called.
864 *
865 * \return Positive on success, negative on errors. If no mood is currently
866 * open, the function returns success.
867 *
868 * \sa mood_open(), mood_close().
869 */
870 static int reload_current_mood(void)
871 {
872 int ret;
873 char *mood_name = NULL;
874
875 ret = clear_score_table();
876 if (ret < 0)
877 return ret;
878 if (!current_mood)
879 return 1;
880 PARA_NOTICE_LOG("reloading %s\n", current_mood->name?
881 current_mood->name : "(dummy)");
882 if (current_mood->name)
883 mood_name = para_strdup(current_mood->name);
884 close_current_mood();
885 ret = change_current_mood(mood_name);
886 free(mood_name);
887 return ret;
888 }
889
890 /**
891 * Notification callback for the moods table.
892 *
893 * \param event Type of the event just occurred.
894 * \param pb Unused.
895 * \param data Its type depends on the event.
896 *
897 * This function performs actions required due to the occurrence of the given
898 * event. Possible actions include reload of the current mood and update of the
899 * score of an audio file.
900 *
901 * \return Standard.
902 */
903 int moods_event_handler(enum afs_events event, __a_unused struct para_buffer *pb,
904 void *data)
905 {
906 if (!current_mood)
907 return 0;
908 switch (event) {
909 /*
910 * The three blob events might change the set of admissible files,
911 * so we must reload the score list.
912 */
913 case BLOB_RENAME:
914 case BLOB_REMOVE:
915 case BLOB_ADD:
916 if (data == moods_table || data == playlists_table)
917 return 1; /* no reload necessary for these */
918 return reload_current_mood();
919 /* these also require reload of the score table */
920 case ATTRIBUTE_ADD:
921 case ATTRIBUTE_REMOVE:
922 case ATTRIBUTE_RENAME:
923 return reload_current_mood();
924 /* changes to the aft only require to re-examine the audio file */
925 case AFSI_CHANGE: {
926 struct afsi_change_event_data *aced = data;
927 return mood_update_audio_file(aced->aft_row, aced->old_afsi);
928 }
929 case AFHI_CHANGE:
930 case AUDIO_FILE_RENAME:
931 case AUDIO_FILE_ADD:
932 return mood_update_audio_file(data, NULL);
933 case AUDIO_FILE_REMOVE:
934 return mood_delete_audio_file(data);
935 default:
936 return 1;
937 }
938 }