Merge branch 'refs/heads/t/doxygen'
[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 (ret >= 0)
367 return ret;
368 if (mi) {
369 free(mi->parser_data);
370 free(mi);
371 }
372 return ret;
373 }
374
375 static int load_mood(const struct osl_row *mood_row, struct mood **m)
376 {
377 char *mood_name;
378 struct osl_object mood_def;
379 struct mood_line_parser_data mlpd = {.line_num = 0};
380 int ret;
381
382 *m = NULL;
383 ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
384 if (ret < 0)
385 return ret;
386 if (!*mood_name)
387 return -E_DUMMY_ROW;
388 mlpd.m = alloc_new_mood(mood_name);
389 ret = for_each_line(FELF_READ_ONLY, mood_def.data, mood_def.size,
390 parse_mood_line, &mlpd);
391 osl_close_disk_object(&mood_def);
392 if (ret < 0) {
393 PARA_ERROR_LOG("unable to load mood %s: %s\n", mlpd.m->name,
394 para_strerror(-ret));
395 destroy_mood(mlpd.m);
396 return ret;
397 }
398 *m = mlpd.m;
399 return 1;
400 }
401
402 static int check_mood(struct osl_row *mood_row, void *data)
403 {
404 struct para_buffer *pb = data;
405 char *mood_name;
406 struct osl_object mood_def;
407 struct mood_line_parser_data mlpd = {.line_num = 0};
408
409 int ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
410
411 if (ret < 0) {
412 para_printf(pb, "cannot read mood\n");
413 return ret;
414 }
415 if (!*mood_name) /* ignore dummy row */
416 goto out;
417 para_printf(pb, "checking mood %s...\n", mood_name);
418 ret = for_each_line(FELF_READ_ONLY, mood_def.data, mood_def.size,
419 parse_mood_line, &mlpd);
420 if (ret < 0)
421 para_printf(pb, "mood %s: error in line %u: %s\n", mood_name,
422 mlpd.line_num, para_strerror(-ret));
423 ret = 1; /* don't fail the loop on invalid mood definitions */
424 out:
425 osl_close_disk_object(&mood_def);
426 return ret;
427 }
428
429 /**
430 * Check all moods for syntax errors.
431 *
432 * \param aca Only ->pbout is used for diagnostics.
433 *
434 * \return Negative on fatal errors. Inconsistent mood definitions are not
435 * considered an error.
436 */
437 int mood_check_callback(struct afs_callback_arg *aca)
438 {
439 para_printf(&aca->pbout, "checking moods...\n");
440 return osl(osl_rbtree_loop(moods_table, BLOBCOL_ID, &aca->pbout,
441 check_mood));
442 }
443
444 static int64_t normalized_value(int64_t x, int64_t n, int64_t sum, int64_t qd)
445 {
446 if (!n || !qd)
447 return 0;
448 return 100 * (n * x - sum) / (int64_t)int_sqrt(n) / (int64_t)int_sqrt(qd);
449 }
450
451 static long compute_score(struct afs_info *afsi, long mood_score)
452 {
453 mood_score -= normalized_value(afsi->num_played, statistics.num,
454 statistics.num_played_sum, statistics.num_played_qd);
455 mood_score -= normalized_value(afsi->last_played, statistics.num,
456 statistics.last_played_sum, statistics.last_played_qd);
457 return mood_score / 3;
458 }
459
460 static int add_afs_statistics(const struct osl_row *row)
461 {
462 uint64_t n, x, s, q;
463 struct afs_info afsi;
464 int ret;
465
466 ret = get_afsi_of_row(row, &afsi);
467 if (ret < 0)
468 return ret;
469 n = statistics.num;
470 x = afsi.last_played;
471 s = statistics.last_played_sum;
472 if (n > 0) {
473 q = (x > s / n)? x - s / n : s / n - x;
474 statistics.last_played_qd += q * q * n / (n + 1);
475 }
476 statistics.last_played_sum += x;
477
478 x = afsi.num_played;
479 s = statistics.num_played_sum;
480 if (n > 0) {
481 q = (x > s / n)? x - s / n : s / n - x;
482 statistics.num_played_qd += q * q * n / (n + 1);
483 }
484 statistics.num_played_sum += x;
485 statistics.num++;
486 return 1;
487 }
488
489 static int del_afs_statistics(const struct osl_row *row)
490 {
491 uint64_t n, s, q, a, new_s;
492 struct afs_info afsi;
493 int ret;
494 ret = get_afsi_of_row(row, &afsi);
495 if (ret < 0)
496 return ret;
497 n = statistics.num;
498 assert(n);
499 if (n == 1) {
500 memset(&statistics, 0, sizeof(statistics));
501 return 1;
502 }
503
504 s = statistics.last_played_sum;
505 q = statistics.last_played_qd;
506 a = afsi.last_played;
507 new_s = s - a;
508 statistics.last_played_sum = new_s;
509 statistics.last_played_qd = q + s * s / n - a * a
510 - new_s * new_s / (n - 1);
511
512 s = statistics.num_played_sum;
513 q = statistics.num_played_qd;
514 a = afsi.num_played;
515 new_s = s - a;
516 statistics.num_played_sum = new_s;
517 statistics.num_played_qd = q + s * s / n - a * a
518 - new_s * new_s / (n - 1);
519
520 statistics.num--;
521 return 1;
522 }
523
524 /*
525 * At mood open time we determine the set of admissible files for the given
526 * mood. The mood score of each admissible file is computed by adding up all
527 * mood item scores. Next, we update the afs statistics and append a struct
528 * admissible_file_info to a temporary array.
529 *
530 * When all files have been processed in this way, the final score of each
531 * admissible file is computed by adding the dynamic score (which depends on
532 * the afs_statistics and the current time) to the mood score. Finally, all
533 * audio files in the temporary array are added to the score table and the
534 * array is freed.
535 */
536 struct admissible_file_info
537 {
538 /** The admissible audio file. */
539 struct osl_row *aft_row;
540 /** Its score. */
541 long score;
542 };
543
544 /** The temporary array of admissible files. */
545 struct admissible_array {
546 /** Files are admissible wrt. this mood. */
547 struct mood *m;
548 /** The size of the array */
549 unsigned size;
550 /** Pointer to the array of admissible files. */
551 struct admissible_file_info *array;
552 };
553
554 /**
555 * Add an entry to the array of admissible files.
556 *
557 * \param aft_row The audio file to be added.
558 * \param private_data Pointer to a struct admissible_file_info.
559 *
560 * \return 1 if row admissible, 0 if not, negative on errors.
561 */
562 static int add_if_admissible(struct osl_row *aft_row, void *data)
563 {
564 struct admissible_array *aa = data;
565 int ret;
566 long score = 0;
567
568 ret = row_is_admissible(aft_row, aa->m, &score);
569 if (ret <= 0)
570 return ret;
571 if (statistics.num >= aa->size) {
572 aa->size *= 2;
573 aa->size += 100;
574 aa->array = para_realloc(aa->array,
575 aa->size * sizeof(struct admissible_file_info));
576 }
577 aa->array[statistics.num].aft_row = aft_row;
578 aa->array[statistics.num].score = score;
579 ret = add_afs_statistics(aft_row);
580 if (ret < 0)
581 return ret;
582 return 1;
583 }
584
585 /**
586 * Compute the new quadratic deviation in case one element changes.
587 *
588 * \param n Number of elements.
589 * \param old_qd The quadratic deviation before the change.
590 * \param old_val The value that was replaced.
591 * \param new_val The replacement value.
592 * \param old_sum The sum of all elements before the update.
593 *
594 * \return The new quadratic deviation resulting from replacing old_val
595 * by new_val.
596 *
597 * Given n real numbers a_1, ..., a_n, their sum S = a_1 + ... + a_n,
598 * their quadratic deviation
599 *
600 * q = (a_1 - S/n)^2 + ... + (a_n - S/n)^2,
601 *
602 * and a real number b, the quadratic deviation q' of a_1,...a_{n-1}, b (ie.
603 * the last number a_n was replaced by b) may be computed in O(1) time in terms
604 * of n, q, a_n, b, and S as
605 *
606 * q' = q + d * s - (2 * S + d) * d / n
607 * = q + d * (s - 2 * S / n - d /n),
608 *
609 * where d = b - a_n, and s = b + a_n.
610 *
611 * Example: n = 3, a_1 = 3, a_2 = 5, a_3 = 7, b = 10. Then S = 15, q = 8, d = 3,
612 * s = 17, so
613 *
614 * q + d * s - (2 * S + d) * d / n = 8 + 51 - 33 = 26,
615 *
616 * which equals q' = (3 - 6)^2 + (5 - 6)^2 + (10 - 6)^2.
617 *
618 */
619 _static_inline_ int64_t update_quadratic_deviation(int64_t n, int64_t old_qd,
620 int64_t old_val, int64_t new_val, int64_t old_sum)
621 {
622 int64_t delta = new_val - old_val;
623 int64_t sigma = new_val + old_val;
624 return old_qd + delta * (sigma - 2 * old_sum / n - delta / n);
625 }
626
627 static int update_afs_statistics(struct afs_info *old_afsi,
628 struct afs_info *new_afsi)
629 {
630 unsigned n;
631 int ret = get_num_admissible_files(&n);
632
633 if (ret < 0)
634 return ret;
635 assert(n);
636
637 statistics.last_played_qd = update_quadratic_deviation(n,
638 statistics.last_played_qd, old_afsi->last_played,
639 new_afsi->last_played, statistics.last_played_sum);
640 statistics.last_played_sum += new_afsi->last_played - old_afsi->last_played;
641
642 statistics.num_played_qd = update_quadratic_deviation(n,
643 statistics.num_played_qd, old_afsi->num_played,
644 new_afsi->num_played, statistics.num_played_sum);
645 statistics.num_played_sum += new_afsi->num_played - old_afsi->num_played;
646 return 1;
647 }
648
649 static int add_to_score_table(const struct osl_row *aft_row, long mood_score)
650 {
651 long score;
652 struct afs_info afsi;
653 int ret = get_afsi_of_row(aft_row, &afsi);
654
655 if (ret < 0)
656 return ret;
657 score = compute_score(&afsi, mood_score);
658 return score_add(aft_row, score);
659 }
660
661 static int delete_from_statistics_and_score_table(const struct osl_row *aft_row)
662 {
663 int ret = del_afs_statistics(aft_row);
664 if (ret < 0)
665 return ret;
666 return score_delete(aft_row);
667 }
668
669 /**
670 * Delete one entry from the statistics and from the score table.
671 *
672 * \param aft_row The audio file which is no longer admissible.
673 *
674 * \return Positive on success, negative on errors.
675 *
676 * \sa \ref score_delete().
677 */
678 static int mood_delete_audio_file(const struct osl_row *aft_row)
679 {
680 int ret;
681
682 ret = row_belongs_to_score_table(aft_row, NULL);
683 if (ret < 0)
684 return ret;
685 if (!ret) /* not admissible, nothing to do */
686 return 1;
687 return delete_from_statistics_and_score_table(aft_row);
688 }
689
690 /**
691 * Compute the new score of an audio file wrt. the current mood.
692 *
693 * \param aft_row Determines the audio file.
694 * \param old_afsi The audio file selector info before updating.
695 *
696 * The \a old_afsi argument may be \p NULL which indicates that no changes to
697 * the audio file info were made.
698 *
699 * \return Positive on success, negative on errors.
700 */
701 static int mood_update_audio_file(const struct osl_row *aft_row,
702 struct afs_info *old_afsi)
703 {
704 long score, percent;
705 int ret, is_admissible, was_admissible = 0;
706 struct afs_info afsi;
707 unsigned rank;
708
709 if (!current_mood)
710 return 1; /* nothing to do */
711 ret = row_belongs_to_score_table(aft_row, &rank);
712 if (ret < 0)
713 return ret;
714 was_admissible = ret;
715 ret = row_is_admissible(aft_row, current_mood, &score);
716 if (ret < 0)
717 return ret;
718 is_admissible = (ret > 0);
719 if (!was_admissible && !is_admissible)
720 return 1;
721 if (was_admissible && !is_admissible)
722 return delete_from_statistics_and_score_table(aft_row);
723 if (!was_admissible && is_admissible) {
724 ret = add_afs_statistics(aft_row);
725 if (ret < 0)
726 return ret;
727 return add_to_score_table(aft_row, score);
728 }
729 /* update score */
730 ret = get_afsi_of_row(aft_row, &afsi);
731 if (ret < 0)
732 return ret;
733 if (old_afsi) {
734 ret = update_afs_statistics(old_afsi, &afsi);
735 if (ret < 0)
736 return ret;
737 }
738 score = compute_score(&afsi, score);
739 PARA_DEBUG_LOG("score: %li\n", score);
740 percent = (score + 100) / 3;
741 if (percent > 100)
742 percent = 100;
743 else if (percent < 0)
744 percent = 0;
745 PARA_DEBUG_LOG("moving from rank %u to %li%%\n", rank, percent);
746 return score_update(aft_row, percent);
747 }
748
749 static void log_statistics(void)
750 {
751 unsigned n = statistics.num;
752 int mean_days, sigma_days;
753 /*
754 * We can not use the "now" pointer from sched.c here because we are
755 * called before schedule(), which initializes "now".
756 */
757 struct timeval rnow;
758
759 assert(current_mood);
760 PARA_NOTICE_LOG("loaded mood %s\n", current_mood->name?
761 current_mood->name : "(dummy)");
762 if (!n) {
763 PARA_WARNING_LOG("no admissible files\n");
764 return;
765 }
766 PARA_NOTICE_LOG("%u admissible files\n", statistics.num);
767 clock_get_realtime(&rnow);
768 mean_days = (rnow.tv_sec - statistics.last_played_sum / n) / 3600 / 24;
769 sigma_days = int_sqrt(statistics.last_played_qd / n) / 3600 / 24;
770 PARA_NOTICE_LOG("last_played mean/sigma: %d/%d days\n", mean_days, sigma_days);
771 PARA_NOTICE_LOG("num_played mean/sigma: %llu/%llu\n",
772 (long long unsigned)statistics.num_played_sum / n,
773 (long long unsigned)int_sqrt(statistics.num_played_qd / n));
774 }
775
776 /**
777 * Close the current mood.
778 *
779 * Frees all resources of the current mood.
780 */
781 void close_current_mood(void)
782 {
783 destroy_mood(current_mood);
784 current_mood = NULL;
785 memset(&statistics, 0, sizeof(statistics));
786 }
787
788 /**
789 * Change the current mood.
790 *
791 * \param mood_name The name of the mood to open.
792 *
793 * If \a mood_name is \a NULL, load the dummy mood that accepts every audio file
794 * and uses a scoring method based only on the \a last_played information.
795 *
796 * If there is already an open mood, it will be closed first.
797 *
798 * \return Positive on success, negative on errors. Loading the dummy mood
799 * always succeeds.
800 *
801 * \sa struct \ref afs_info::last_played.
802 */
803 int change_current_mood(const char *mood_name)
804 {
805 int i, ret;
806 struct admissible_array aa = {
807 .size = 0,
808 .array = NULL
809 };
810
811 if (mood_name) {
812 struct mood *m;
813 struct osl_row *row;
814 struct osl_object obj = {
815 .data = (char *)mood_name,
816 .size = strlen(mood_name) + 1
817 };
818 ret = osl(osl_get_row(moods_table, BLOBCOL_NAME, &obj, &row));
819 if (ret < 0) {
820 PARA_NOTICE_LOG("no such mood: %s\n", mood_name);
821 return ret;
822 }
823 ret = load_mood(row, &m);
824 if (ret < 0)
825 return ret;
826 close_current_mood();
827 current_mood = m;
828 } else { /* load dummy mood */
829 close_current_mood();
830 current_mood = alloc_new_mood(NULL);
831 }
832 aa.m = current_mood;
833 PARA_NOTICE_LOG("computing statistics of admissible files\n");
834 ret = audio_file_loop(&aa, add_if_admissible);
835 if (ret < 0)
836 return ret;
837 for (i = 0; i < statistics.num; i++) {
838 struct admissible_file_info *a = aa.array + i;
839 ret = add_to_score_table(a->aft_row, a->score);
840 if (ret < 0)
841 goto out;
842 }
843 log_statistics();
844 ret = statistics.num;
845 out:
846 free(aa.array);
847 return ret;
848 }
849
850 /*
851 * Close and re-open the current mood.
852 *
853 * This function is called on events which render the current list of
854 * admissible files useless, for example if an attribute is removed from the
855 * attribute table.
856 *
857 * If no mood is currently open, the function returns success.
858 */
859 static int reload_current_mood(void)
860 {
861 int ret;
862 char *mood_name = NULL;
863
864 ret = clear_score_table();
865 if (ret < 0)
866 return ret;
867 if (!current_mood)
868 return 1;
869 PARA_NOTICE_LOG("reloading %s\n", current_mood->name?
870 current_mood->name : "(dummy)");
871 if (current_mood->name)
872 mood_name = para_strdup(current_mood->name);
873 close_current_mood();
874 ret = change_current_mood(mood_name);
875 free(mood_name);
876 return ret;
877 }
878
879 /**
880 * Notification callback for the moods table.
881 *
882 * \param event Type of the event just occurred.
883 * \param pb Unused.
884 * \param data Its type depends on the event.
885 *
886 * This function performs actions required due to the occurrence of the given
887 * event. Possible actions include reload of the current mood and update of the
888 * score of an audio file.
889 *
890 * \return Standard.
891 */
892 int moods_event_handler(enum afs_events event, __a_unused struct para_buffer *pb,
893 void *data)
894 {
895 if (!current_mood)
896 return 0;
897 switch (event) {
898 /*
899 * The three blob events might change the set of admissible files,
900 * so we must reload the score list.
901 */
902 case BLOB_RENAME:
903 case BLOB_REMOVE:
904 case BLOB_ADD:
905 if (data == moods_table || data == playlists_table)
906 return 1; /* no reload necessary for these */
907 return reload_current_mood();
908 /* these also require reload of the score table */
909 case ATTRIBUTE_ADD:
910 case ATTRIBUTE_REMOVE:
911 case ATTRIBUTE_RENAME:
912 return reload_current_mood();
913 /* changes to the aft only require to re-examine the audio file */
914 case AFSI_CHANGE: {
915 struct afsi_change_event_data *aced = data;
916 return mood_update_audio_file(aced->aft_row, aced->old_afsi);
917 }
918 case AFHI_CHANGE:
919 case AUDIO_FILE_RENAME:
920 case AUDIO_FILE_ADD:
921 return mood_update_audio_file(data, NULL);
922 case AUDIO_FILE_REMOVE:
923 return mood_delete_audio_file(data);
924 default:
925 return 1;
926 }
927 }