027a77d4db05bd33698f082ab8c11b03c26b1a06
[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 \ref change_current_mood().
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 accept,
67 * deny, or score which determines the type of the mood line. For each such
68 * type a linked list is maintained whose entries are the mood items.
69 */
70 struct mood {
71 /** The name of this mood. */
72 char *name;
73 /** The list of mood items of type \p accept. */
74 struct list_head accept_list;
75 /** The list of mood items of type \p deny. */
76 struct list_head deny_list;
77 /** The list of mood items of type \p score. */
78 struct list_head score_list;
79 };
80
81 /*
82 * If current_mood is NULL then no mood is currently open. If
83 * current_mood->name is NULL, the dummy mood is currently open.
84 */
85 static struct mood *current_mood;
86
87 /**
88 * Rough approximation to sqrt.
89 *
90 * \param x Integer of which to calculate the sqrt.
91 *
92 * \return An integer res with res * res <= x.
93 */
94 __a_const static uint64_t int_sqrt(uint64_t x)
95 {
96 uint64_t op, res, one = 1;
97 op = x;
98 res = 0;
99
100 one = one << 62;
101 while (one > op)
102 one >>= 2;
103
104 while (one != 0) {
105 if (op >= res + one) {
106 op = op - (res + one);
107 res = res + 2 * one;
108 }
109 res /= 2;
110 one /= 4;
111 }
112 // PARA_NOTICE_LOG("sqrt(%llu) = %llu\n", x, res);
113 return res;
114 }
115
116 /*
117 * Returns true if row matches, false if it does not match. In any case score
118 * and score_arg_sum are set/increased accordingly.
119 */
120 static bool get_item_score(struct mood_item *item, const struct afs_info *afsi,
121 const struct afh_info *afhi, const char *path, long *score,
122 long *score_arg_sum)
123 {
124 int ret;
125 bool match = true;
126
127 *score_arg_sum += item->random_score? 100 : PARA_ABS(item->score_arg);
128 ret = 100;
129 if (item->method) {
130 ret = item->method->score_function(path, afsi, afhi,
131 item->parser_data);
132 if ((ret < 0 && !item->logical_not) || (ret >= 0 && item->logical_not))
133 match = false;
134 }
135 if (item->random_score)
136 *score = PARA_ABS(ret) * para_random(100);
137 else
138 *score = PARA_ABS(ret) * item->score_arg;
139 return match;
140 }
141
142 /* returns 1 if row admissible, 0 if not, negative on errors */
143 static int row_is_admissible(const struct osl_row *aft_row, struct mood *m,
144 long *scorep)
145 {
146 struct mood_item *item;
147 int ret;
148 bool match;
149 long score_arg_sum = 0, score = 0, item_score;
150 struct afs_info afsi;
151 struct afh_info afhi;
152 char *path;
153
154 if (!m)
155 return -E_NO_MOOD;
156 ret = get_afsi_of_row(aft_row, &afsi);
157 if (ret < 0)
158 return ret;
159 ret = get_afhi_of_row(aft_row, &afhi);
160 if (ret < 0)
161 return ret;
162 ret = get_audio_file_path_of_row(aft_row, &path);
163 if (ret < 0)
164 return ret;
165 /* reject audio file if it matches any entry in the deny list */
166 list_for_each_entry(item, &m->deny_list, mood_item_node) {
167 match = get_item_score(item, &afsi, &afhi, path, &item_score,
168 &score_arg_sum);
169 if (match) /* not admissible */
170 return 0;
171 score += item_score;
172 }
173 match = false;
174 list_for_each_entry(item, &m->accept_list, mood_item_node) {
175 ret = get_item_score(item, &afsi, &afhi, path, &item_score,
176 &score_arg_sum);
177 if (ret == 0)
178 continue;
179 match = true;
180 score += item_score;
181 }
182 /* reject if there is no matching entry in the accept list */
183 if (!match && !list_empty(&m->accept_list))
184 return 0;
185 list_for_each_entry(item, &m->score_list, mood_item_node) {
186 match = get_item_score(item, &afsi, &afhi, path, &item_score,
187 &score_arg_sum);
188 if (match)
189 score += item_score;
190 }
191 if (score_arg_sum)
192 score /= score_arg_sum;
193 *scorep = score;
194 return 1;
195 }
196
197 static void cleanup_list_entry(struct mood_item *item)
198 {
199 if (item->method && item->method->cleanup)
200 item->method->cleanup(item->parser_data);
201 else
202 free(item->parser_data);
203 list_del(&item->mood_item_node);
204 free(item);
205 }
206
207 static void destroy_mood(struct mood *m)
208 {
209 struct mood_item *tmp, *item;
210
211 if (!m)
212 return;
213 list_for_each_entry_safe(item, tmp, &m->accept_list, mood_item_node)
214 cleanup_list_entry(item);
215 list_for_each_entry_safe(item, tmp, &m->deny_list, mood_item_node)
216 cleanup_list_entry(item);
217 list_for_each_entry_safe(item, tmp, &m->score_list, mood_item_node)
218 cleanup_list_entry(item);
219 free(m->name);
220 free(m);
221 }
222
223 static struct mood *alloc_new_mood(const char *name)
224 {
225 struct mood *m = para_calloc(sizeof(struct mood));
226 if (name)
227 m->name = para_strdup(name);
228 INIT_LIST_HEAD(&m->accept_list);
229 INIT_LIST_HEAD(&m->deny_list);
230 INIT_LIST_HEAD(&m->score_list);
231 return m;
232 }
233
234 /** The different types of a mood line. */
235 enum mood_line_type {
236 /** Invalid. */
237 ML_INVALID,
238 /** Accept line. */
239 ML_ACCEPT,
240 /** Deny line. */
241 ML_DENY,
242 /** Score line. */
243 ML_SCORE
244 };
245
246 /** Data passed to the parser of a mood line. */
247 struct mood_line_parser_data {
248 /** The mood this mood line belongs to. */
249 struct mood *m;
250 /** The line number in the mood definition. */
251 unsigned line_num;
252 };
253
254 /*
255 * <accept [with score <score>] | deny [with score <score>] | score <score>>
256 * [if] [not] <mood_method> [options]
257 * <score> is either an integer or "random" which assigns a random score to
258 * all matching files
259 */
260 static int parse_mood_line(char *mood_line, void *data)
261 {
262 struct mood_line_parser_data *mlpd = data;
263 char **argv;
264 unsigned num_words;
265 char **w;
266 int i, ret;
267 enum mood_line_type mlt = ML_INVALID;
268 struct mood_item *mi = NULL;
269
270 mlpd->line_num++;
271 ret = create_argv(mood_line, " \t", &argv);
272 if (ret < 0)
273 return ret;
274 num_words = ret;
275 if (!num_words) /* empty line */
276 goto out;
277 w = argv;
278 if (**w == '#') /* comment */
279 goto out;
280 if (!strcmp(*w, "accept"))
281 mlt = ML_ACCEPT;
282 else if (!strcmp(*w, "deny"))
283 mlt = ML_DENY;
284 else if (!strcmp(*w, "score"))
285 mlt = ML_SCORE;
286 ret = -E_MOOD_SYNTAX;
287 if (mlt == ML_INVALID)
288 goto out;
289 mi = para_calloc(sizeof(struct mood_item));
290 if (mlt != ML_SCORE) {
291 ret = -E_MOOD_SYNTAX;
292 w++;
293 if (!*w)
294 goto out;
295 if (strcmp(*w, "with"))
296 goto check_for_if;
297 w++;
298 if (!*w)
299 goto out;
300 if (strcmp(*w, "score"))
301 goto out;
302 }
303 if (mlt == ML_SCORE || !strcmp(*w, "score")) {
304 ret = -E_MOOD_SYNTAX;
305 w++;
306 if (!*w)
307 goto out;
308 if (strcmp(*w, "random")) {
309 mi->random_score = 0;
310 ret = para_atoi32(*w, &mi->score_arg);
311 if (ret < 0)
312 goto out;
313 } else {
314 mi->random_score = 1;
315 if (!*(w + 1))
316 goto success; /* the line "score random" is valid */
317 }
318 } else
319 mi->score_arg = 0;
320 ret = -E_MOOD_SYNTAX;
321 w++;
322 if (!*w)
323 goto out;
324 check_for_if:
325 if (!strcmp(*w, "if")) {
326 ret = -E_MOOD_SYNTAX;
327 w++;
328 if (!*w)
329 goto out;
330 }
331 if (!strcmp(*w, "not")) {
332 ret = -E_MOOD_SYNTAX;
333 w++;
334 if (!*w)
335 goto out;
336 mi->logical_not = 1;
337 } else
338 mi->logical_not = 0;
339 for (i = 0; mood_methods[i].parser; i++) {
340 if (strcmp(*w, mood_methods[i].name))
341 continue;
342 break;
343 }
344 ret = -E_MOOD_SYNTAX;
345 if (!mood_methods[i].parser)
346 goto out;
347 ret = mood_methods[i].parser(num_words - 1 - (w - argv), w,
348 &mi->parser_data);
349 if (ret < 0)
350 goto out;
351 mi->method = &mood_methods[i];
352 success:
353 if (mlpd->m) {
354 if (mlt == ML_ACCEPT)
355 para_list_add(&mi->mood_item_node, &mlpd->m->accept_list);
356 else if (mlt == ML_DENY)
357 para_list_add(&mi->mood_item_node, &mlpd->m->deny_list);
358 else
359 para_list_add(&mi->mood_item_node, &mlpd->m->score_list);
360 }
361 PARA_DEBUG_LOG("%s entry added, method: %p\n", mlt == ML_ACCEPT? "accept" :
362 (mlt == ML_DENY? "deny" : "score"), mi->method);
363 ret = 1;
364 out:
365 free_argv(argv);
366 if (mi && (ret < 0 || !mlpd->m)) { /* mi was not added to any list */
367 free(mi->parser_data);
368 free(mi);
369 }
370 return ret;
371 }
372
373 static int load_mood(const struct osl_row *mood_row, struct mood **m)
374 {
375 char *mood_name;
376 struct osl_object mood_def;
377 struct mood_line_parser_data mlpd = {.line_num = 0};
378 int ret;
379
380 *m = NULL;
381 ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
382 if (ret < 0)
383 return ret;
384 if (!*mood_name)
385 return -E_DUMMY_ROW;
386 mlpd.m = alloc_new_mood(mood_name);
387 ret = for_each_line(FELF_READ_ONLY, mood_def.data, mood_def.size,
388 parse_mood_line, &mlpd);
389 osl_close_disk_object(&mood_def);
390 if (ret < 0) {
391 PARA_ERROR_LOG("unable to load mood %s: %s\n", mlpd.m->name,
392 para_strerror(-ret));
393 destroy_mood(mlpd.m);
394 return ret;
395 }
396 *m = mlpd.m;
397 return 1;
398 }
399
400 static int check_mood(struct osl_row *mood_row, void *data)
401 {
402 struct para_buffer *pb = data;
403 char *mood_name;
404 struct osl_object mood_def;
405 struct mood_line_parser_data mlpd = {.line_num = 0};
406
407 int ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
408
409 if (ret < 0) {
410 para_printf(pb, "cannot read mood\n");
411 return ret;
412 }
413 if (!*mood_name) /* ignore dummy row */
414 goto out;
415 para_printf(pb, "checking mood %s...\n", mood_name);
416 ret = for_each_line(FELF_READ_ONLY, mood_def.data, mood_def.size,
417 parse_mood_line, &mlpd);
418 if (ret < 0)
419 para_printf(pb, "mood %s: error in line %u: %s\n", mood_name,
420 mlpd.line_num, para_strerror(-ret));
421 ret = 1; /* don't fail the loop on invalid mood definitions */
422 out:
423 osl_close_disk_object(&mood_def);
424 return ret;
425 }
426
427 /**
428 * Check all moods for syntax errors.
429 *
430 * \param aca Only ->pbout is used for diagnostics.
431 *
432 * \return Negative on fatal errors. Inconsistent mood definitions are not
433 * considered an error.
434 */
435 int mood_check_callback(struct afs_callback_arg *aca)
436 {
437 para_printf(&aca->pbout, "checking moods...\n");
438 return osl(osl_rbtree_loop(moods_table, BLOBCOL_ID, &aca->pbout,
439 check_mood));
440 }
441
442 static int64_t normalized_value(int64_t x, int64_t n, int64_t sum, int64_t qd)
443 {
444 if (!n || !qd)
445 return 0;
446 return 100 * (n * x - sum) / (int64_t)int_sqrt(n) / (int64_t)int_sqrt(qd);
447 }
448
449 static long compute_score(struct afs_info *afsi, long mood_score)
450 {
451 mood_score -= normalized_value(afsi->num_played, statistics.num,
452 statistics.num_played_sum, statistics.num_played_qd);
453 mood_score -= normalized_value(afsi->last_played, statistics.num,
454 statistics.last_played_sum, statistics.last_played_qd);
455 return mood_score / 3;
456 }
457
458 static int add_afs_statistics(const struct osl_row *row)
459 {
460 uint64_t n, x, s, q;
461 struct afs_info afsi;
462 int ret;
463
464 ret = get_afsi_of_row(row, &afsi);
465 if (ret < 0)
466 return ret;
467 n = statistics.num;
468 x = afsi.last_played;
469 s = statistics.last_played_sum;
470 if (n > 0) {
471 q = (x > s / n)? x - s / n : s / n - x;
472 statistics.last_played_qd += q * q * n / (n + 1);
473 }
474 statistics.last_played_sum += x;
475
476 x = afsi.num_played;
477 s = statistics.num_played_sum;
478 if (n > 0) {
479 q = (x > s / n)? x - s / n : s / n - x;
480 statistics.num_played_qd += q * q * n / (n + 1);
481 }
482 statistics.num_played_sum += x;
483 statistics.num++;
484 return 1;
485 }
486
487 static int del_afs_statistics(const struct osl_row *row)
488 {
489 uint64_t n, s, q, a, new_s;
490 struct afs_info afsi;
491 int ret;
492 ret = get_afsi_of_row(row, &afsi);
493 if (ret < 0)
494 return ret;
495 n = statistics.num;
496 assert(n);
497 if (n == 1) {
498 memset(&statistics, 0, sizeof(statistics));
499 return 1;
500 }
501
502 s = statistics.last_played_sum;
503 q = statistics.last_played_qd;
504 a = afsi.last_played;
505 new_s = s - a;
506 statistics.last_played_sum = new_s;
507 statistics.last_played_qd = q + s * s / n - a * a
508 - new_s * new_s / (n - 1);
509
510 s = statistics.num_played_sum;
511 q = statistics.num_played_qd;
512 a = afsi.num_played;
513 new_s = s - a;
514 statistics.num_played_sum = new_s;
515 statistics.num_played_qd = q + s * s / n - a * a
516 - new_s * new_s / (n - 1);
517
518 statistics.num--;
519 return 1;
520 }
521
522 /*
523 * At mood open time we determine the set of admissible files for the given
524 * mood. The mood score of each admissible file is computed by adding up all
525 * mood item scores. Next, we update the afs statistics and append a struct
526 * admissible_file_info to a temporary array.
527 *
528 * When all files have been processed in this way, the final score of each
529 * admissible file is computed by adding the dynamic score (which depends on
530 * the afs_statistics and the current time) to the mood score. Finally, all
531 * audio files in the temporary array are added to the score table and the
532 * array is freed.
533 */
534 struct admissible_file_info
535 {
536 /** The admissible audio file. */
537 struct osl_row *aft_row;
538 /** Its score. */
539 long score;
540 };
541
542 /** The temporary array of admissible files. */
543 struct admissible_array {
544 /** Files are admissible wrt. this mood. */
545 struct mood *m;
546 /** The size of the array */
547 unsigned size;
548 /** Pointer to the array of admissible files. */
549 struct admissible_file_info *array;
550 };
551
552 /**
553 * Add an entry to the array of admissible files.
554 *
555 * \param aft_row The audio file to be added.
556 * \param private_data Pointer to a struct admissible_file_info.
557 *
558 * \return 1 if row admissible, 0 if not, negative on errors.
559 */
560 static int add_if_admissible(struct osl_row *aft_row, void *data)
561 {
562 struct admissible_array *aa = data;
563 int ret;
564 long score = 0;
565
566 ret = row_is_admissible(aft_row, aa->m, &score);
567 if (ret <= 0)
568 return ret;
569 if (statistics.num >= aa->size) {
570 aa->size *= 2;
571 aa->size += 100;
572 aa->array = para_realloc(aa->array,
573 aa->size * sizeof(struct admissible_file_info));
574 }
575 aa->array[statistics.num].aft_row = aft_row;
576 aa->array[statistics.num].score = score;
577 ret = add_afs_statistics(aft_row);
578 if (ret < 0)
579 return ret;
580 return 1;
581 }
582
583 /**
584 * Compute the new quadratic deviation in case one element changes.
585 *
586 * \param n Number of elements.
587 * \param old_qd The quadratic deviation before the change.
588 * \param old_val The value that was replaced.
589 * \param new_val The replacement value.
590 * \param old_sum The sum of all elements before the update.
591 *
592 * \return The new quadratic deviation resulting from replacing old_val
593 * by new_val.
594 *
595 * Given n real numbers a_1, ..., a_n, their sum S = a_1 + ... + a_n,
596 * their quadratic deviation
597 *
598 * q = (a_1 - S/n)^2 + ... + (a_n - S/n)^2,
599 *
600 * and a real number b, the quadratic deviation q' of a_1,...a_{n-1}, b (ie.
601 * the last number a_n was replaced by b) may be computed in O(1) time in terms
602 * of n, q, a_n, b, and S as
603 *
604 * q' = q + d * s - (2 * S + d) * d / n
605 * = q + d * (s - 2 * S / n - d /n),
606 *
607 * where d = b - a_n, and s = b + a_n.
608 *
609 * Example: n = 3, a_1 = 3, a_2 = 5, a_3 = 7, b = 10. Then S = 15, q = 8, d = 3,
610 * s = 17, so
611 *
612 * q + d * s - (2 * S + d) * d / n = 8 + 51 - 33 = 26,
613 *
614 * which equals q' = (3 - 6)^2 + (5 - 6)^2 + (10 - 6)^2.
615 *
616 */
617 _static_inline_ int64_t update_quadratic_deviation(int64_t n, int64_t old_qd,
618 int64_t old_val, int64_t new_val, int64_t old_sum)
619 {
620 int64_t delta = new_val - old_val;
621 int64_t sigma = new_val + old_val;
622 return old_qd + delta * (sigma - 2 * old_sum / n - delta / n);
623 }
624
625 static int update_afs_statistics(struct afs_info *old_afsi,
626 struct afs_info *new_afsi)
627 {
628 unsigned n;
629 int ret = get_num_admissible_files(&n);
630
631 if (ret < 0)
632 return ret;
633 assert(n);
634
635 statistics.last_played_qd = update_quadratic_deviation(n,
636 statistics.last_played_qd, old_afsi->last_played,
637 new_afsi->last_played, statistics.last_played_sum);
638 statistics.last_played_sum += new_afsi->last_played - old_afsi->last_played;
639
640 statistics.num_played_qd = update_quadratic_deviation(n,
641 statistics.num_played_qd, old_afsi->num_played,
642 new_afsi->num_played, statistics.num_played_sum);
643 statistics.num_played_sum += new_afsi->num_played - old_afsi->num_played;
644 return 1;
645 }
646
647 static int add_to_score_table(const struct osl_row *aft_row, long mood_score)
648 {
649 long score;
650 struct afs_info afsi;
651 int ret = get_afsi_of_row(aft_row, &afsi);
652
653 if (ret < 0)
654 return ret;
655 score = compute_score(&afsi, mood_score);
656 return score_add(aft_row, score);
657 }
658
659 static int delete_from_statistics_and_score_table(const struct osl_row *aft_row)
660 {
661 int ret = del_afs_statistics(aft_row);
662 if (ret < 0)
663 return ret;
664 return score_delete(aft_row);
665 }
666
667 /**
668 * Delete one entry from the statistics and from the score table.
669 *
670 * \param aft_row The audio file which is no longer admissible.
671 *
672 * \return Positive on success, negative on errors.
673 *
674 * \sa \ref score_delete().
675 */
676 static int mood_delete_audio_file(const struct osl_row *aft_row)
677 {
678 int ret;
679
680 ret = row_belongs_to_score_table(aft_row, NULL);
681 if (ret < 0)
682 return ret;
683 if (!ret) /* not admissible, nothing to do */
684 return 1;
685 return delete_from_statistics_and_score_table(aft_row);
686 }
687
688 /**
689 * Compute the new score of an audio file wrt. the current mood.
690 *
691 * \param aft_row Determines the audio file.
692 * \param old_afsi The audio file selector info before updating.
693 *
694 * The \a old_afsi argument may be \p NULL which indicates that no changes to
695 * the audio file info were made.
696 *
697 * \return Positive on success, negative on errors.
698 */
699 static int mood_update_audio_file(const struct osl_row *aft_row,
700 struct afs_info *old_afsi)
701 {
702 long score, percent;
703 int ret, is_admissible, was_admissible = 0;
704 struct afs_info afsi;
705 unsigned rank;
706
707 if (!current_mood)
708 return 1; /* nothing to do */
709 ret = row_belongs_to_score_table(aft_row, &rank);
710 if (ret < 0)
711 return ret;
712 was_admissible = ret;
713 ret = row_is_admissible(aft_row, current_mood, &score);
714 if (ret < 0)
715 return ret;
716 is_admissible = (ret > 0);
717 if (!was_admissible && !is_admissible)
718 return 1;
719 if (was_admissible && !is_admissible)
720 return delete_from_statistics_and_score_table(aft_row);
721 if (!was_admissible && is_admissible) {
722 ret = add_afs_statistics(aft_row);
723 if (ret < 0)
724 return ret;
725 return add_to_score_table(aft_row, score);
726 }
727 /* update score */
728 ret = get_afsi_of_row(aft_row, &afsi);
729 if (ret < 0)
730 return ret;
731 if (old_afsi) {
732 ret = update_afs_statistics(old_afsi, &afsi);
733 if (ret < 0)
734 return ret;
735 }
736 score = compute_score(&afsi, score);
737 PARA_DEBUG_LOG("score: %li\n", score);
738 percent = (score + 100) / 3;
739 if (percent > 100)
740 percent = 100;
741 else if (percent < 0)
742 percent = 0;
743 PARA_DEBUG_LOG("moving from rank %u to %li%%\n", rank, percent);
744 return score_update(aft_row, percent);
745 }
746
747 static void log_statistics(void)
748 {
749 unsigned n = statistics.num;
750 int mean_days, sigma_days;
751 /*
752 * We can not use the "now" pointer from sched.c here because we are
753 * called before schedule(), which initializes "now".
754 */
755 struct timeval rnow;
756
757 assert(current_mood);
758 PARA_NOTICE_LOG("loaded mood %s\n", current_mood->name?
759 current_mood->name : "(dummy)");
760 if (!n) {
761 PARA_WARNING_LOG("no admissible files\n");
762 return;
763 }
764 PARA_NOTICE_LOG("%u admissible files\n", statistics.num);
765 clock_get_realtime(&rnow);
766 mean_days = (rnow.tv_sec - statistics.last_played_sum / n) / 3600 / 24;
767 sigma_days = int_sqrt(statistics.last_played_qd / n) / 3600 / 24;
768 PARA_NOTICE_LOG("last_played mean/sigma: %d/%d days\n", mean_days, sigma_days);
769 PARA_NOTICE_LOG("num_played mean/sigma: %llu/%llu\n",
770 (long long unsigned)statistics.num_played_sum / n,
771 (long long unsigned)int_sqrt(statistics.num_played_qd / n));
772 }
773
774 /**
775 * Close the current mood.
776 *
777 * Frees all resources of the current mood.
778 */
779 void close_current_mood(void)
780 {
781 destroy_mood(current_mood);
782 current_mood = NULL;
783 memset(&statistics, 0, sizeof(statistics));
784 }
785
786 /**
787 * Change the current mood.
788 *
789 * \param mood_name The name of the mood to open.
790 *
791 * If \a mood_name is \a NULL, load the dummy mood that accepts every audio file
792 * and uses a scoring method based only on the \a last_played information.
793 *
794 * If there is already an open mood, it will be closed first.
795 *
796 * \return Positive on success, negative on errors. Loading the dummy mood
797 * always succeeds.
798 *
799 * \sa struct \ref afs_info::last_played.
800 */
801 int change_current_mood(const char *mood_name)
802 {
803 int i, ret;
804 struct admissible_array aa = {
805 .size = 0,
806 .array = NULL
807 };
808
809 if (mood_name) {
810 struct mood *m;
811 struct osl_row *row;
812 struct osl_object obj = {
813 .data = (char *)mood_name,
814 .size = strlen(mood_name) + 1
815 };
816 ret = osl(osl_get_row(moods_table, BLOBCOL_NAME, &obj, &row));
817 if (ret < 0) {
818 PARA_NOTICE_LOG("no such mood: %s\n", mood_name);
819 return ret;
820 }
821 ret = load_mood(row, &m);
822 if (ret < 0)
823 return ret;
824 close_current_mood();
825 current_mood = m;
826 } else { /* load dummy mood */
827 close_current_mood();
828 current_mood = alloc_new_mood(NULL);
829 }
830 aa.m = current_mood;
831 PARA_NOTICE_LOG("computing statistics of admissible files\n");
832 ret = audio_file_loop(&aa, add_if_admissible);
833 if (ret < 0)
834 return ret;
835 for (i = 0; i < statistics.num; i++) {
836 struct admissible_file_info *a = aa.array + i;
837 ret = add_to_score_table(a->aft_row, a->score);
838 if (ret < 0)
839 goto out;
840 }
841 log_statistics();
842 ret = statistics.num;
843 out:
844 free(aa.array);
845 return ret;
846 }
847
848 /*
849 * Close and re-open the current mood.
850 *
851 * This function is called on events which render the current list of
852 * admissible files useless, for example if an attribute is removed from the
853 * attribute table.
854 *
855 * If no mood is currently open, the function returns success.
856 */
857 static int reload_current_mood(void)
858 {
859 int ret;
860 char *mood_name = NULL;
861
862 ret = clear_score_table();
863 if (ret < 0)
864 return ret;
865 if (!current_mood)
866 return 1;
867 PARA_NOTICE_LOG("reloading %s\n", current_mood->name?
868 current_mood->name : "(dummy)");
869 if (current_mood->name)
870 mood_name = para_strdup(current_mood->name);
871 close_current_mood();
872 ret = change_current_mood(mood_name);
873 free(mood_name);
874 return ret;
875 }
876
877 /**
878 * Notification callback for the moods table.
879 *
880 * \param event Type of the event just occurred.
881 * \param pb Unused.
882 * \param data Its type depends on the event.
883 *
884 * This function performs actions required due to the occurrence of the given
885 * event. Possible actions include reload of the current mood and update of the
886 * score of an audio file.
887 *
888 * \return Standard.
889 */
890 int moods_event_handler(enum afs_events event, __a_unused struct para_buffer *pb,
891 void *data)
892 {
893 if (!current_mood)
894 return 0;
895 switch (event) {
896 /*
897 * The three blob events might change the set of admissible files,
898 * so we must reload the score list.
899 */
900 case BLOB_RENAME:
901 case BLOB_REMOVE:
902 case BLOB_ADD:
903 if (data == moods_table || data == playlists_table)
904 return 1; /* no reload necessary for these */
905 return reload_current_mood();
906 /* these also require reload of the score table */
907 case ATTRIBUTE_ADD:
908 case ATTRIBUTE_REMOVE:
909 case ATTRIBUTE_RENAME:
910 return reload_current_mood();
911 /* changes to the aft only require to re-examine the audio file */
912 case AFSI_CHANGE: {
913 struct afsi_change_event_data *aced = data;
914 return mood_update_audio_file(aced->aft_row, aced->old_afsi);
915 }
916 case AFHI_CHANGE:
917 case AUDIO_FILE_RENAME:
918 case AUDIO_FILE_ADD:
919 return mood_update_audio_file(data, NULL);
920 case AUDIO_FILE_REMOVE:
921 return mood_delete_audio_file(data);
922 default:
923 return 1;
924 }
925 }