Define status items in para.h.
[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 row_is_admissible(const struct osl_row *aft_row, struct mood *m,
146 long *scorep)
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 *scorep = 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 static int parse_mood_line(char *mood_line, void *data)
263 {
264 struct mood_line_parser_data *mlpd = data;
265 char **argv;
266 unsigned num_words;
267 char **w;
268 int i, ret;
269 enum mood_line_type mlt = ML_INVALID;
270 struct mood_item *mi = NULL;
271
272 mlpd->line_num++;
273 ret = create_argv(mood_line, " \t", &argv);
274 if (ret < 0)
275 return ret;
276 num_words = ret;
277 if (!num_words) /* empty line */
278 goto out;
279 w = argv;
280 if (**w == '#') /* comment */
281 goto out;
282 if (!strcmp(*w, "accept"))
283 mlt = ML_ACCEPT;
284 else if (!strcmp(*w, "deny"))
285 mlt = ML_DENY;
286 else if (!strcmp(*w, "score"))
287 mlt = ML_SCORE;
288 ret = -E_MOOD_SYNTAX;
289 if (mlt == ML_INVALID)
290 goto out;
291 mi = para_calloc(sizeof(struct mood_item));
292 if (mlt != ML_SCORE) {
293 ret = -E_MOOD_SYNTAX;
294 w++;
295 if (!*w)
296 goto out;
297 if (strcmp(*w, "with"))
298 goto check_for_if;
299 w++;
300 if (!*w)
301 goto out;
302 if (strcmp(*w, "score"))
303 goto out;
304 }
305 if (mlt == ML_SCORE || !strcmp(*w, "score")) {
306 ret = -E_MOOD_SYNTAX;
307 w++;
308 if (!*w)
309 goto out;
310 if (strcmp(*w, "random")) {
311 mi->random_score = 0;
312 ret = para_atoi32(*w, &mi->score_arg);
313 if (ret < 0)
314 goto out;
315 } else {
316 mi->random_score = 1;
317 if (!*(w + 1))
318 goto success; /* the line "score random" is valid */
319 }
320 } else
321 mi->score_arg = 0;
322 ret = -E_MOOD_SYNTAX;
323 w++;
324 if (!*w)
325 goto out;
326 check_for_if:
327 if (!strcmp(*w, "if")) {
328 ret = -E_MOOD_SYNTAX;
329 w++;
330 if (!*w)
331 goto out;
332 }
333 if (!strcmp(*w, "not")) {
334 ret = -E_MOOD_SYNTAX;
335 w++;
336 if (!*w)
337 goto out;
338 mi->logical_not = 1;
339 } else
340 mi->logical_not = 0;
341 for (i = 0; mood_methods[i].parser; i++) {
342 if (strcmp(*w, mood_methods[i].name))
343 continue;
344 break;
345 }
346 ret = -E_MOOD_SYNTAX;
347 if (!mood_methods[i].parser)
348 goto out;
349 ret = mood_methods[i].parser(num_words - 1 - (w - argv), w,
350 &mi->parser_data);
351 if (ret < 0)
352 goto out;
353 mi->method = &mood_methods[i];
354 success:
355 if (mlpd->m) {
356 if (mlt == ML_ACCEPT)
357 para_list_add(&mi->mood_item_node, &mlpd->m->accept_list);
358 else if (mlt == ML_DENY)
359 para_list_add(&mi->mood_item_node, &mlpd->m->deny_list);
360 else
361 para_list_add(&mi->mood_item_node, &mlpd->m->score_list);
362 }
363 PARA_DEBUG_LOG("%s entry added, method: %p\n", mlt == ML_ACCEPT? "accept" :
364 (mlt == ML_DENY? "deny" : "score"), mi->method);
365 ret = 1;
366 out:
367 free_argv(argv);
368 if (ret >= 0)
369 return ret;
370 if (mi) {
371 free(mi->parser_data);
372 free(mi);
373 }
374 return ret;
375 }
376
377 static int load_mood(const struct osl_row *mood_row, struct mood **m)
378 {
379 char *mood_name;
380 struct osl_object mood_def;
381 struct mood_line_parser_data mlpd = {.line_num = 0};
382 int ret;
383
384 *m = NULL;
385 ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
386 if (ret < 0)
387 return ret;
388 if (!*mood_name)
389 return -E_DUMMY_ROW;
390 mlpd.m = alloc_new_mood(mood_name);
391 ret = for_each_line(FELF_READ_ONLY, mood_def.data, mood_def.size,
392 parse_mood_line, &mlpd);
393 osl_close_disk_object(&mood_def);
394 if (ret < 0) {
395 PARA_ERROR_LOG("unable to load mood %s: %s\n", mlpd.m->name,
396 para_strerror(-ret));
397 destroy_mood(mlpd.m);
398 return ret;
399 }
400 *m = mlpd.m;
401 return 1;
402 }
403
404 static int check_mood(struct osl_row *mood_row, void *data)
405 {
406 struct para_buffer *pb = data;
407 char *mood_name;
408 struct osl_object mood_def;
409 struct mood_line_parser_data mlpd = {.line_num = 0};
410
411 int ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
412
413 if (ret < 0) {
414 para_printf(pb, "cannot read mood\n");
415 return ret;
416 }
417 if (!*mood_name) /* ignore dummy row */
418 goto out;
419 para_printf(pb, "checking mood %s...\n", mood_name);
420 ret = for_each_line(FELF_READ_ONLY, mood_def.data, mood_def.size,
421 parse_mood_line, &mlpd);
422 if (ret < 0)
423 para_printf(pb, "mood %s: error in line %u: %s\n", mood_name,
424 mlpd.line_num, para_strerror(-ret));
425 ret = 1; /* don't fail the loop on invalid mood definitions */
426 out:
427 osl_close_disk_object(&mood_def);
428 return ret;
429 }
430
431 /**
432 * Check all moods for syntax errors.
433 *
434 * \param aca Only ->pbout is used for diagnostics.
435 *
436 * \return Negative on fatal errors. Inconsistent mood definitions are not
437 * considered an error.
438 */
439 int mood_check_callback(struct afs_callback_arg *aca)
440 {
441 para_printf(&aca->pbout, "checking moods...\n");
442 return osl(osl_rbtree_loop(moods_table, BLOBCOL_ID, &aca->pbout,
443 check_mood));
444 }
445
446 static int64_t normalized_value(int64_t x, int64_t n, int64_t sum, int64_t qd)
447 {
448 if (!n || !qd)
449 return 0;
450 return 100 * (n * x - sum) / (int64_t)int_sqrt(n) / (int64_t)int_sqrt(qd);
451 }
452
453 static long compute_score(struct afs_info *afsi, long mood_score)
454 {
455 mood_score -= normalized_value(afsi->num_played, statistics.num,
456 statistics.num_played_sum, statistics.num_played_qd);
457 mood_score -= normalized_value(afsi->last_played, statistics.num,
458 statistics.last_played_sum, statistics.last_played_qd);
459 return mood_score / 3;
460 }
461
462 static int add_afs_statistics(const struct osl_row *row)
463 {
464 uint64_t n, x, s, q;
465 struct afs_info afsi;
466 int ret;
467
468 ret = get_afsi_of_row(row, &afsi);
469 if (ret < 0)
470 return ret;
471 n = statistics.num;
472 x = afsi.last_played;
473 s = statistics.last_played_sum;
474 if (n > 0) {
475 q = (x > s / n)? x - s / n : s / n - x;
476 statistics.last_played_qd += q * q * n / (n + 1);
477 }
478 statistics.last_played_sum += x;
479
480 x = afsi.num_played;
481 s = statistics.num_played_sum;
482 if (n > 0) {
483 q = (x > s / n)? x - s / n : s / n - x;
484 statistics.num_played_qd += q * q * n / (n + 1);
485 }
486 statistics.num_played_sum += x;
487 statistics.num++;
488 return 1;
489 }
490
491 static int del_afs_statistics(const struct osl_row *row)
492 {
493 uint64_t n, s, q, a, new_s;
494 struct afs_info afsi;
495 int ret;
496 ret = get_afsi_of_row(row, &afsi);
497 if (ret < 0)
498 return ret;
499 n = statistics.num;
500 assert(n);
501 if (n == 1) {
502 memset(&statistics, 0, sizeof(statistics));
503 return 1;
504 }
505
506 s = statistics.last_played_sum;
507 q = statistics.last_played_qd;
508 a = afsi.last_played;
509 new_s = s - a;
510 statistics.last_played_sum = new_s;
511 statistics.last_played_qd = q + s * s / n - a * a
512 - new_s * new_s / (n - 1);
513
514 s = statistics.num_played_sum;
515 q = statistics.num_played_qd;
516 a = afsi.num_played;
517 new_s = s - a;
518 statistics.num_played_sum = new_s;
519 statistics.num_played_qd = q + s * s / n - a * a
520 - new_s * new_s / (n - 1);
521
522 statistics.num--;
523 return 1;
524 }
525
526 /**
527 * Structure used during mood_open().
528 *
529 * At mood open time we determine the set of admissible files for the given
530 * mood. The mood score of each admissible file is computed by adding up all
531 * mood item scores. Next, we update the afs statistics and append a struct
532 * admissible_file_info to a temporary array.
533 *
534 * When all files have been processed in this way, the final score of each
535 * admissible file is computed by adding the dynamic score (which depends on
536 * the afs_statistics and the current time) to the mood score. Finally, all
537 * audio files in the temporary array are added to the score table and the
538 * array is freed.
539 *
540 * \sa mood_method, admissible_array.
541 */
542 struct admissible_file_info
543 {
544 /** The admissible audio file. */
545 struct osl_row *aft_row;
546 /** Its score. */
547 long score;
548 };
549
550 /** The temporary array of admissible files. */
551 struct admissible_array {
552 /** Files are admissible wrt. this mood. */
553 struct mood *m;
554 /** The size of the array */
555 unsigned size;
556 /** Pointer to the array of admissible files. */
557 struct admissible_file_info *array;
558 };
559
560 /**
561 * Add an entry to the array of admissible files.
562 *
563 * \param aft_row The audio file to be added.
564 * \param private_data Pointer to a struct admissible_file_info.
565 *
566 * \return 1 if row admissible, 0 if not, negative on errors.
567 */
568 static int add_if_admissible(struct osl_row *aft_row, void *data)
569 {
570 struct admissible_array *aa = data;
571 int ret;
572 long score = 0;
573
574 ret = row_is_admissible(aft_row, aa->m, &score);
575 if (ret <= 0)
576 return ret;
577 if (statistics.num >= aa->size) {
578 aa->size *= 2;
579 aa->size += 100;
580 aa->array = para_realloc(aa->array,
581 aa->size * sizeof(struct admissible_file_info));
582 }
583 aa->array[statistics.num].aft_row = aft_row;
584 aa->array[statistics.num].score = score;
585 ret = add_afs_statistics(aft_row);
586 if (ret < 0)
587 return ret;
588 return 1;
589 }
590
591 /**
592 * Compute the new quadratic deviation in case one element changes.
593 *
594 * \param n Number of elements.
595 * \param old_qd The quadratic deviation before the change.
596 * \param old_val The value that was replaced.
597 * \param new_val The replacement value.
598 * \param old_sum The sum of all elements before the update.
599 *
600 * \return The new quadratic deviation resulting from replacing old_val
601 * by new_val.
602 *
603 * Given n real numbers a_1, ..., a_n, their sum S = a_1 + ... + a_n,
604 * their quadratic deviation
605 *
606 * q = (a_1 - S/n)^2 + ... + (a_n - S/n)^2,
607 *
608 * and a real number b, the quadratic deviation q' of a_1,...a_{n-1}, b (ie.
609 * the last number a_n was replaced by b) may be computed in O(1) time in terms
610 * of n, q, a_n, b, and S as
611 *
612 * q' = q + d * s - (2 * S + d) * d / n
613 * = q + d * (s - 2 * S / n - d /n),
614 *
615 * where d = b - a_n, and s = b + a_n.
616 *
617 * Example: n = 3, a_1 = 3, a_2 = 5, a_3 = 7, b = 10. Then S = 15, q = 8, d = 3,
618 * s = 17, so
619 *
620 * q + d * s - (2 * S + d) * d / n = 8 + 51 - 33 = 26,
621 *
622 * which equals q' = (3 - 6)^2 + (5 - 6)^2 + (10 - 6)^2.
623 *
624 */
625 _static_inline_ int64_t update_quadratic_deviation(int64_t n, int64_t old_qd,
626 int64_t old_val, int64_t new_val, int64_t old_sum)
627 {
628 int64_t delta = new_val - old_val;
629 int64_t sigma = new_val + old_val;
630 return old_qd + delta * (sigma - 2 * old_sum / n - delta / n);
631 }
632
633 static int update_afs_statistics(struct afs_info *old_afsi,
634 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 = row_is_admissible(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 /**
859 * Close and re-open the current mood.
860 *
861 * This function is used if changes to the audio file table or the
862 * attribute table were made that render the current list of admissible
863 * files useless. For example, if an attribute is removed from the
864 * attribute table, this function is called.
865 *
866 * \return Positive on success, negative on errors. If no mood is currently
867 * open, the function returns success.
868 *
869 * \sa mood_open(), mood_close().
870 */
871 static int reload_current_mood(void)
872 {
873 int ret;
874 char *mood_name = NULL;
875
876 ret = clear_score_table();
877 if (ret < 0)
878 return ret;
879 if (!current_mood)
880 return 1;
881 PARA_NOTICE_LOG("reloading %s\n", current_mood->name?
882 current_mood->name : "(dummy)");
883 if (current_mood->name)
884 mood_name = para_strdup(current_mood->name);
885 close_current_mood();
886 ret = change_current_mood(mood_name);
887 free(mood_name);
888 return ret;
889 }
890
891 /**
892 * Notification callback for the moods table.
893 *
894 * \param event Type of the event just occurred.
895 * \param pb Unused.
896 * \param data Its type depends on the event.
897 *
898 * This function performs actions required due to the occurrence of the given
899 * event. Possible actions include reload of the current mood and update of the
900 * score of an audio file.
901 *
902 * \return Standard.
903 */
904 int moods_event_handler(enum afs_events event, __a_unused struct para_buffer *pb,
905 void *data)
906 {
907 if (!current_mood)
908 return 0;
909 switch (event) {
910 /*
911 * The three blob events might change the set of admissible files,
912 * so we must reload the score list.
913 */
914 case BLOB_RENAME:
915 case BLOB_REMOVE:
916 case BLOB_ADD:
917 if (data == moods_table || data == playlists_table)
918 return 1; /* no reload necessary for these */
919 return reload_current_mood();
920 /* these also require reload of the score table */
921 case ATTRIBUTE_ADD:
922 case ATTRIBUTE_REMOVE:
923 case ATTRIBUTE_RENAME:
924 return reload_current_mood();
925 /* changes to the aft only require to re-examine the audio file */
926 case AFSI_CHANGE: {
927 struct afsi_change_event_data *aced = data;
928 return mood_update_audio_file(aced->aft_row, aced->old_afsi);
929 }
930 case AFHI_CHANGE:
931 case AUDIO_FILE_RENAME:
932 case AUDIO_FILE_ADD:
933 return mood_update_audio_file(data, NULL);
934 case AUDIO_FILE_REMOVE:
935 return mood_delete_audio_file(data);
936 default:
937 return 1;
938 }
939 }