mood.c: Rename mood_loop() to load_mood_loop_func().
[paraslash.git] / mood.c
1 /*
2 * Copyright (C) 2007 Andre Noll <maan@systemlinux.org>
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 "para.h"
10 #include "error.h"
11 #include "afh.h"
12 #include "afs.h"
13 #include "list.h"
14 #include "string.h"
15
16 /**
17 * Contains statistical data of the currently admissible audio files.
18 *
19 * It is used to assign normalized score values to each admissbile audio file.
20 */
21 struct afs_statistics {
22 /** sum of num played over all admissible files */
23 int64_t num_played_sum;
24 /** sum of last played times over all admissible files */
25 int64_t last_played_sum;
26 /** quadratic deviation of num played time */
27 int64_t num_played_qd;
28 /** quadratic deviation of last played time */
29 int64_t last_played_qd;
30 /** number of admissible files */
31 unsigned num;
32 };
33 struct afs_statistics statistics;
34
35 /**
36 * Assign scores according to a mood_method.
37 *
38 * Each mood_method has its own mood_score_function. The first parameter passed
39 * to that function is a pointer to a row of the audio file table. It
40 * determines the audio file for which a score is to be assigned. The second
41 * argument depends on the mood method this function is used for. It usually is
42 * the argument given at the end of a mood line.
43 *
44 * Mood score functions must return values between -100 and +100 inclisively.
45 * Boolean score functions should always return either -100 or +100.
46 *
47 * \sa struct mood_method, mood_parser.
48 */
49 typedef int mood_score_function(const struct osl_row*, void *);
50
51 /**
52 * Preprocess a mood line.
53 *
54 * The mood_parser of a mood_method is called once at mood open time for each
55 * line of the current mood definition that contains the mood_method's name as
56 * a keyword. The line is passed to the mood_parser as the first argument. The
57 * mood_parser must determine whether the line is syntactically correct and
58 * return a positive value if so and a negative value otherwise.
59 *
60 * Some mood parsers preprocess the data given in the mood line to compute a
61 * structure which depends of the particular mood_method and which is used
62 * later in the mood_score_function of the mood_method. The mood_parser may
63 * store a pointer to its structure via the second argument.
64 *
65 * \sa mood_open(), mood_cleanup_function, mood_score_function.
66 */
67 typedef int mood_parser(const char *, void **);
68
69 /**
70 * Deallocate resources which were allocated by the mood_parser.
71 *
72 * This optional function of a mood_method is used to free any resources
73 * allocated in mood_open() by the mood_parser. The argument passed is a
74 * pointer to the mood_method specific data structure that was returned by the
75 * mood_parser.
76 *
77 * \sa mood_parser.
78 */
79 typedef void mood_cleanup_function(void *);
80
81 /**
82 * Used for scoring and to determine whether a file is admissible.
83 */
84 struct mood_method {
85 /* The name of the method. */
86 const char *name;
87 /** Pointer to the mood parser. */
88 mood_parser *parser;
89 /** Pointer to the score function */
90 mood_score_function *score_function;
91 /** Optional cleanup function. */
92 mood_cleanup_function *cleanup;
93 };
94
95 /**
96 * Each line of the current mood corresponds to a mood_item.
97 */
98 struct mood_item {
99 /** The method this line is referring to. */
100 const struct mood_method *method;
101 /** The data structure computed by the mood parser. */
102 void *parser_data;
103 /** The given score value, or zero if none was given. */
104 long score_arg;
105 /** Non-zero if random scoring was requested. */
106 int random_score;
107 /** Whether the "not" keyword was given in the mood line. */
108 int logical_not;
109 /** The position in the list of items. */
110 struct list_head mood_item_node;
111 };
112
113 /**
114 * Created from the mood definition by mood_open().
115 *
116 * When a mood is opened, each line of its definition is investigated, and a
117 * corresponding mood item is produced. Each mood line starts with \p accept,
118 * \p deny, or \p score which determins the type of the mood line. For each
119 * such type a linked list is maintained whose entries are the mood items.
120 *
121 * \sa mood_item, mood_open().
122 */
123 struct mood {
124 /** The name of this mood. */
125 char *name;
126 /** The list of mood items of type \p accept. */
127 struct list_head accept_list;
128 /** The list of mood items of type \p deny. */
129 struct list_head deny_list;
130 /** The list of mood items of type \p score. */
131 struct list_head score_list;
132 };
133
134 static struct mood *current_mood;
135
136 /**
137 * Rough approximation to sqrt.
138 *
139 * \param x Integer of which to calculate the sqrt.
140 *
141 * \return An integer res with res * res <= x.
142 */
143 static uint64_t int_sqrt(uint64_t x)
144 {
145 uint64_t op, res, one = 1;
146 op = x;
147 res = 0;
148
149 one = one << 62;
150 while (one > op)
151 one >>= 2;
152
153 while (one != 0) {
154 if (op >= res + one) {
155 op = op - (res + one);
156 res = res + 2 * one;
157 }
158 res /= 2;
159 one /= 4;
160 }
161 // PARA_NOTICE_LOG("sqrt(%llu) = %llu\n", x, res);
162 return res;
163 }
164
165 static int mm_played_rarely_score_function(const struct osl_row *row,
166 __a_unused void *ignored)
167 {
168 struct afs_info afsi;
169 unsigned num;
170 int ret = get_afsi_of_row(row, &afsi);
171
172 if (ret < 0)
173 return 0;
174 ret = get_num_admissible_files(&num);
175 if (ret < 0)
176 return 0;
177 if (statistics.num_played_sum - num * afsi.num_played
178 > int_sqrt(statistics.num_played_qd * num))
179 return 100;
180 return -100;
181 }
182
183 static int mm_played_rarely_parser(const char *arg, __a_unused void **ignored)
184 {
185 if (*arg)
186 PARA_WARNING_LOG("ignored junk at eol: %s\n", arg);
187 return 1;
188 }
189
190 static int mm_name_like_score_function(const struct osl_row *row, void *preg)
191 {
192 char *path;
193 int ret = get_audio_file_path_of_row(row, &path);
194
195 if (ret < 0)
196 return 0;
197 ret = regexec((regex_t *)preg, path, 42, NULL, 0);
198 return (ret == REG_NOMATCH)? -100 : 100;
199 }
200
201 static int mm_name_like_parser(const char *arg, void **regex)
202 {
203 regex_t *preg = para_malloc(sizeof(*preg));
204 int ret = regcomp(preg, arg, REG_NOSUB);
205
206 if (ret) {
207 free(preg);
208 return -E_MOOD_REGEX;
209 }
210 *regex = preg;
211 return 1;
212 }
213
214 static void mm_name_like_cleanup(void *preg)
215 {
216 regfree(preg);
217 free(preg);
218 }
219
220 static int mm_is_set_parser(const char *arg, void **bitnum)
221 {
222 unsigned char *c = para_malloc(1);
223 int ret = get_attribute_bitnum_by_name(arg, c);
224
225 if (ret >= 0)
226 *bitnum = c;
227 else
228 free(c);
229 return ret;
230 }
231
232 static int mm_is_set_score_function(const struct osl_row *row, void *bitnum)
233 {
234 unsigned char *bn = bitnum;
235 struct afs_info afsi;
236 int ret = get_afsi_of_row(row, &afsi);
237
238 if (ret < 0)
239 return 0;
240 if (afsi.attributes & (1ULL << *bn))
241 return 100;
242 return -100;
243 }
244
245 /* returns 1 if row matches score item, -1 otherwise */
246 static int add_item_score(const struct osl_row *row, struct mood_item *item, long *score,
247 long *score_arg_sum)
248 {
249 int ret = 100;
250
251 *score_arg_sum += item->random_score? 100 : PARA_ABS(item->score_arg);
252 if (item->method) {
253 ret = item->method->score_function(row, item->parser_data);
254 if ((ret < 0 && !item->logical_not) || (ret >= 0 && item->logical_not))
255 return -1; /* no match */
256 }
257 if (item->random_score)
258 *score += PARA_ABS(ret) * para_random(100);
259 else
260 *score += PARA_ABS(ret) * item->score_arg;
261 return 1;
262 }
263
264 static int compute_mood_score(const struct osl_row *aft_row, struct mood *m,
265 long *result)
266 {
267 struct mood_item *item;
268 int match = 0;
269 long score_arg_sum = 0, score = 0;
270
271 if (!m)
272 return -E_NO_MOOD;
273 /* reject audio file if it matches any entry in the deny list */
274 list_for_each_entry(item, &m->deny_list, mood_item_node)
275 if (add_item_score(aft_row, item, &score, &score_arg_sum) > 0)
276 return -E_NOT_ADMISSIBLE;
277 list_for_each_entry(item, &m->accept_list, mood_item_node)
278 if (add_item_score(aft_row, item, &score, &score_arg_sum) > 0)
279 match = 1;
280 /* reject if there is no matching entry in the accept list */
281 if (!match && !list_empty(&m->accept_list))
282 return -E_NOT_ADMISSIBLE;
283 list_for_each_entry(item, &m->score_list, mood_item_node)
284 add_item_score(aft_row, item, &score, &score_arg_sum);
285 if (score_arg_sum)
286 score /= score_arg_sum;
287 *result = score;
288 return 1;
289 }
290
291 static const struct mood_method mood_methods[] = {
292 {
293 .parser = mm_played_rarely_parser,
294 .score_function = mm_played_rarely_score_function,
295 .name = "played_rarely"
296 },
297 {
298 .parser = mm_is_set_parser,
299 .score_function = mm_is_set_score_function,
300 .name = "is_set"
301 },
302 {
303 .parser = mm_name_like_parser,
304 .score_function = mm_name_like_score_function,
305 .cleanup = mm_name_like_cleanup,
306 .name = "name_like"
307 },
308 {
309 .parser = NULL
310 }
311 };
312
313 static void cleanup_list_entry(struct mood_item *item)
314 {
315 if (item->method && item->method->cleanup)
316 item->method->cleanup(item->parser_data);
317 else
318 free(item->parser_data);
319 list_del(&item->mood_item_node);
320 free(item);
321 }
322
323 static void destroy_mood(struct mood *m)
324 {
325 struct mood_item *tmp, *item;
326
327 if (!m)
328 return;
329 list_for_each_entry_safe(item, tmp, &m->accept_list, mood_item_node)
330 cleanup_list_entry(item);
331 list_for_each_entry_safe(item, tmp, &m->deny_list, mood_item_node)
332 cleanup_list_entry(item);
333 list_for_each_entry_safe(item, tmp, &m->score_list, mood_item_node)
334 cleanup_list_entry(item);
335 free(m->name);
336 free(m);
337 }
338
339 static struct mood *alloc_new_mood(const char *name)
340 {
341 struct mood *m = para_calloc(sizeof(struct mood));
342 m->name = para_strdup(name);
343 INIT_LIST_HEAD(&m->accept_list);
344 INIT_LIST_HEAD(&m->deny_list);
345 INIT_LIST_HEAD(&m->score_list);
346 return m;
347 }
348
349 /** The different types of a mood line. */
350 enum mood_line_type {
351 /** Invalid. */
352 ML_INVALID,
353 /** Accept line. */
354 ML_ACCEPT,
355 /** Deny line. */
356 ML_DENY,
357 /** Score line. */
358 ML_SCORE
359 };
360
361 /*
362 * <accept [with score <score>] | deny [with score <score>] | score <score>>
363 * [if] [not] <mood_method> [options]
364 * <score> is either an integer or "random" which assigns a random score to
365 * all matching files
366 */
367
368 static int parse_mood_line(char *mood_line, void *data)
369 {
370 struct mood *m = data;
371 char **argv;
372 char *delim = " \t";
373 unsigned num_words;
374 char **w;
375 int i, ret;
376 enum mood_line_type mlt = ML_INVALID;
377 struct mood_item *mi = NULL;
378 char *buf = para_strdup(mood_line);
379
380 num_words = split_args(buf, &argv, delim);
381 ret = 1;
382 if (!num_words) /* empty line */
383 goto out;
384 w = argv;
385 if (**w == '#') /* comment */
386 goto out;
387 if (!strcmp(*w, "accept"))
388 mlt = ML_ACCEPT;
389 else if (!strcmp(*w, "deny"))
390 mlt = ML_DENY;
391 else if (!strcmp(*w, "score"))
392 mlt = ML_SCORE;
393 ret = -E_MOOD_SYNTAX;
394 if (mlt == ML_INVALID)
395 goto out;
396 mi = para_calloc(sizeof(struct mood_item));
397 if (mlt != ML_SCORE) {
398 ret = -E_MOOD_SYNTAX;
399 w++;
400 if (!*w)
401 goto out;
402 if (!strcmp(*w, "with")) {
403 w++;
404 if (!*w)
405 goto out;
406 }
407 }
408 if (mlt == ML_SCORE || !strcmp(*w, "score")) {
409 ret = -E_MOOD_SYNTAX;
410 w++;
411 if (!*w)
412 goto out;
413 if (strcmp(*w, "random")) {
414 mi->random_score = 0;
415 ret = para_atol(*w, &mi->score_arg);
416 if (ret < 0)
417 goto out;
418 } else {
419 mi->random_score = 1;
420 if (!*(w + 1))
421 goto success; /* the line "score random" is valid */
422 }
423 } else
424 mi->score_arg = 0;
425 ret = -E_MOOD_SYNTAX;
426 w++;
427 if (!*w)
428 goto out;
429 if (!strcmp(*w, "if")) {
430 ret = -E_MOOD_SYNTAX;
431 w++;
432 if (!*w)
433 goto out;
434 }
435 if (!strcmp(*w, "not")) {
436 ret = -E_MOOD_SYNTAX;
437 w++;
438 if (!*w)
439 goto out;
440 mi->logical_not = 1;
441 } else
442 mi->logical_not = 0;
443 for (i = 0; mood_methods[i].parser; i++) {
444 if (strcmp(*w, mood_methods[i].name))
445 continue;
446 break;
447 }
448 ret = -E_MOOD_SYNTAX;
449 if (!mood_methods[i].parser)
450 goto out;
451 w++;
452 ret = mood_methods[i].parser(*w, &mi->parser_data);
453 if (ret < 0)
454 goto out;
455 mi->method = &mood_methods[i];
456 success:
457 if (mlt == ML_ACCEPT)
458 para_list_add(&mi->mood_item_node, &m->accept_list);
459 else if (mlt == ML_DENY)
460 para_list_add(&mi->mood_item_node, &m->deny_list);
461 else
462 para_list_add(&mi->mood_item_node, &m->score_list);
463 PARA_DEBUG_LOG("%s entry added, method: %p\n", mlt == ML_ACCEPT? "accept" :
464 (mlt == ML_DENY? "deny" : "score"), mi->method);
465 ret = 1;
466 out:
467 free(argv);
468 free(buf);
469 if (ret >= 0)
470 return ret;
471 if (mi) {
472 free(mi->parser_data);
473 free(mi);
474 }
475 return ret;
476 }
477
478 static int load_mood(const struct osl_row *mood_row, struct mood **m)
479 {
480 int ret;
481 struct osl_object objs[NUM_BLOB_COLUMNS];
482
483 ret = osl_get_object(moods_table, mood_row, BLOBCOL_NAME, &objs[BLOBCOL_NAME]);
484 if (ret < 0)
485 return ret;
486 if (objs[BLOBCOL_NAME].size <= 1)
487 return -E_DUMMY_ROW;
488 ret = osl_open_disk_object(moods_table, mood_row, BLOBCOL_DEF, &objs[BLOBCOL_DEF]);
489 if (ret < 0)
490 return ret;
491 *m = alloc_new_mood((char*)objs[BLOBCOL_NAME].data);
492 ret = for_each_line_ro(objs[BLOBCOL_DEF].data, objs[BLOBCOL_DEF].size,
493 parse_mood_line, *m);
494 osl_close_disk_object(&objs[BLOBCOL_DEF]);
495 if (ret < 0) {
496 PARA_ERROR_LOG("unable to load mood %s: %s\n", (*m)->name,
497 PARA_STRERROR(-ret));
498 destroy_mood(*m);
499 return ret;
500 }
501 PARA_INFO_LOG("loaded mood %s\n", (*m)->name);
502 return 1;
503 }
504
505 /*
506 * Calls load_mood() and reverts its error value: It returns -E_MOOD_LOADED
507 * on _success_, and 1 on errors. This way the loop over all moods stops at the
508 * first valid mood.
509 */
510 static int load_mood_loop_func(struct osl_row *mood_row, void *data)
511 {
512 struct mood **m = data;
513 int ret = load_mood(mood_row, m);
514 if (ret < 0) {
515 if (ret != -E_DUMMY_ROW)
516 PARA_NOTICE_LOG("invalid mood (%d), trying next mood\n", ret);
517 return 1;
518 }
519 return -E_MOOD_LOADED;
520 }
521
522 static int load_first_available_mood(struct mood **m)
523 {
524 int ret = osl_rbtree_loop(moods_table, BLOBCOL_NAME, m,
525 load_mood_loop_func);
526 if (ret == -E_MOOD_LOADED) /* success */
527 return 1;
528 if (ret < 0)
529 return ret; /* error */
530 PARA_NOTICE_LOG("no valid mood found\n");
531 return -E_NO_MOOD;
532 }
533
534 #if 0
535 static unsigned int_log2(uint64_t x)
536 {
537 unsigned res = 0;
538
539 while (x) {
540 x /= 2;
541 res++;
542 }
543 return res;
544 }
545 #endif
546
547 static int64_t normalized_value(int64_t x, int64_t n, int64_t sum, int64_t qd)
548 {
549 if (!n || !qd)
550 return 0;
551 return 100 * (n * x - sum) / (int64_t)int_sqrt(n * qd);
552 }
553
554 static long compute_num_played_score(struct afs_info *afsi)
555 {
556 return -normalized_value(afsi->num_played, statistics.num,
557 statistics.num_played_sum, statistics.num_played_qd);
558 }
559
560 static long compute_last_played_score(struct afs_info *afsi)
561 {
562 return -normalized_value(afsi->last_played, statistics.num,
563 statistics.last_played_sum, statistics.last_played_qd);
564 }
565
566 static long compute_dynamic_score(const struct osl_row *aft_row)
567 {
568 struct afs_info afsi;
569 int64_t score, nscore = 0, lscore = 0;
570 int ret;
571
572 ret = get_afsi_of_row(aft_row, &afsi);
573 if (ret < 0)
574 return -100;
575 nscore = compute_num_played_score(&afsi);
576 lscore = compute_last_played_score(&afsi);
577 score = nscore + lscore;
578 return score;
579 }
580
581 static int add_afs_statistics(const struct osl_row *row)
582 {
583 uint64_t n, x, s;
584 struct afs_info afsi;
585 int ret;
586
587 ret = get_afsi_of_row(row, &afsi);
588 if (ret < 0)
589 return ret;
590 n = statistics.num;
591 x = afsi.last_played;
592 s = statistics.last_played_sum;
593 if (n > 0)
594 statistics.last_played_qd += (x - s / n) * (x - s / n) * n / (n + 1);
595 statistics.last_played_sum += x;
596
597 x = afsi.num_played;
598 s = statistics.num_played_sum;
599 if (n > 0)
600 statistics.num_played_qd += (x - s / n) * (x - s / n) * n / (n + 1);
601 statistics.num_played_sum += x;
602 statistics.num++;
603 return 1;
604 }
605
606 static int del_afs_statistics(const struct osl_row *row)
607 {
608 uint64_t n, s, q, a, new_s;
609 struct afs_info afsi;
610 int ret;
611 ret = get_afsi_of_row(row, &afsi);
612 if (ret < 0)
613 return ret;
614 n = statistics.num;
615 assert(n);
616 if (n == 1) {
617 memset(&statistics, 0, sizeof(statistics));
618 return 1;
619 }
620
621 s = statistics.last_played_sum;
622 q = statistics.last_played_qd;
623 a = afsi.last_played;
624 new_s = s - a;
625 statistics.last_played_sum = new_s;
626 statistics.last_played_qd = q + s * s / n - a * a
627 - new_s * new_s / (n - 1);
628
629 s = statistics.num_played_sum;
630 q = statistics.num_played_qd;
631 a = afsi.num_played;
632 new_s = s - a;
633 statistics.num_played_sum = new_s;
634 statistics.num_played_qd = q + s * s / n - a * a
635 - new_s * new_s / (n - 1);
636
637 statistics.num--;
638 return 1;
639 }
640
641 /**
642 * Structure used during mood_open().
643 *
644 * At mood open time, we look at each file in the audio file table in order to
645 * determine whether it is admissible. If a file happens to be admissible, its
646 * mood score is computed by calling each relevant mood_score_function. Next,
647 * we update the afs_statistics and add a struct admissible_file_info to a
648 * temporary array.
649 *
650 * If all files have been processed that way, the final score of each
651 * admissible file is computed by adding the dynamic score (which depends on
652 * the afs_statistics) to the mood score. Finally, all audio files in the
653 * array are added to the score table and the admissible array is freed.
654 *
655 * \sa mood_method, admissible_array.
656 */
657 struct admissible_file_info
658 {
659 /** The admissible audio file. */
660 struct osl_row *aft_row;
661 /** Its score. */
662 long score;
663 };
664
665 /** The temporary array of admissible files. */
666 struct admissible_array {
667 /** Files are admissible wrt. this mood. */
668 struct mood *m;
669 /** The size of the array */
670 unsigned size;
671 /** Pointer to the array of admissible files. */
672 struct admissible_file_info *array;
673 };
674
675 /**
676 * Add an entry to the array of admissible files.
677 *
678 * \param aft_row The audio file to be added.
679 * \param private_data Pointer to a struct admissible_file_info.
680 *
681 * \return Negative on errors, positive on success.
682 */
683 static int add_if_admissible(struct osl_row *aft_row, void *data)
684 {
685 struct admissible_array *aa = data;
686 int ret;
687 long score = 0;
688
689 ret = compute_mood_score(aft_row, aa->m, &score);
690 if (ret < 0)
691 return (ret == -E_NOT_ADMISSIBLE)? 1 : ret;
692 if (statistics.num >= aa->size) {
693 aa->size *= 2;
694 aa->size += 100;
695 aa->array = para_realloc(aa->array,
696 aa->size * sizeof(struct admissible_file_info));
697 }
698 aa->array[statistics.num].aft_row = aft_row;
699 aa->array[statistics.num].score = score;
700 ret = add_afs_statistics(aft_row);
701 if (ret < 0)
702 return ret;
703 return 1;
704 }
705
706 /**
707 * Compute the new quadratic deviation in case one element changes.
708 *
709 * \param n Number of elements.
710 * \param old_qd The quadratic deviation before the change.
711 * \param old_val The value that was repaced.
712 * \param new_val The replacement value.
713 * \param old_sum The sum of all elements before the update.
714 *
715 * \return The new quadratic deviation resulting from replacing old_val
716 * by new_val.
717 *
718 * Given n real numbers a_1, ..., a_n, their sum S = a_1 + ... + a_n,
719 * their quadratic deviation
720 *
721 * q = (a_1 - S/n)^2 + ... + (a_n - S/n)^2,
722 *
723 * and a real number b, the quadratic deviation q' of a_1,...a_{n-1}, b (ie.
724 * the last number a_n was replaced by b) may be computed in O(1) time in terms
725 * of n, q, a_n, b, and S as
726 *
727 * q' = q + d * s - (2 * S + d) * d / n,
728 *
729 * where d = b - a_n, and s = b + a_n.
730 *
731 * Example: n = 3, a_1 = 3, a_2 = 5, a_3 = 7, b = 10. Then S = 15, q = 8, d = 3,
732 * s = 17, so
733 *
734 * q + d * s - (2 * S + d) * d / n = 8 + 51 - 33 = 26,
735 *
736 * which equals q' = (3 - 6)^2 + (5 - 6)^2 + (10 - 6)^2.
737 *
738 */
739 _static_inline_ int64_t update_quadratic_deviation(int64_t n, int64_t old_qd,
740 int64_t old_val, int64_t new_val, int64_t old_sum)
741 {
742 int64_t delta = new_val - old_val;
743 int64_t sigma = new_val + old_val;
744 return old_qd + delta * sigma - (2 * old_sum + delta) * delta / n;
745 }
746
747 static int update_afs_statistics(struct afs_info *old_afsi, struct afs_info *new_afsi)
748 {
749 unsigned n;
750 int ret = get_num_admissible_files(&n);
751
752 if (ret < 0)
753 return ret;
754 assert(n);
755
756 statistics.last_played_qd = update_quadratic_deviation(n,
757 statistics.last_played_qd, old_afsi->last_played,
758 new_afsi->last_played, statistics.last_played_sum);
759 statistics.last_played_sum += new_afsi->last_played - old_afsi->last_played;
760
761 statistics.num_played_qd = update_quadratic_deviation(n,
762 statistics.num_played_qd, old_afsi->num_played,
763 new_afsi->num_played, statistics.num_played_sum);
764 statistics.num_played_sum += new_afsi->num_played - old_afsi->num_played;
765 return 1;
766 }
767
768 static int add_to_score_table(const struct osl_row *aft_row, long mood_score)
769 {
770 long score = (compute_dynamic_score(aft_row) + mood_score) / 3;
771 return score_add(aft_row, score);
772 }
773
774 static int delete_from_statistics_and_score_table(const struct osl_row *aft_row)
775 {
776 int ret = del_afs_statistics(aft_row);
777 if (ret < 0)
778 return ret;
779 return score_delete(aft_row);
780 }
781
782 /**
783 * Delete one entry from the statitics and from the score table.
784 *
785 * \param aft_row The audio file which is no longer admissible.
786 *
787 * \return Positive on success, negative on errors.
788 *
789 * \sa score_delete(), mood_update_audio_file().
790 */
791 int mood_delete_audio_file(const struct osl_row *aft_row)
792 {
793 int ret;
794
795 ret = row_belongs_to_score_table(aft_row);
796 if (ret < 0)
797 return ret;
798 if (!ret) /* not admissible, nothing to do */
799 return 1;
800 return delete_from_statistics_and_score_table(aft_row);
801 }
802
803 /**
804 * Compute the new score of an audio file wrt. the current mood.
805 *
806 * \param aft_row Determines the audio file.
807 * \param old_afsi The audio file selector info before updating.
808 *
809 * The \a old_afsi argument may be \p NULL which indicates that no changes to
810 * the audio file info were made.
811 *
812 * \return Positive on success, negative on errors.
813 */
814 int mood_update_audio_file(const struct osl_row *aft_row, struct afs_info *old_afsi)
815 {
816 long score, percent;
817 int ret, is_admissible, was_admissible = 0;
818 struct afs_info afsi;
819
820 if (!current_mood)
821 return 1; /* nothing to do */
822 ret = row_belongs_to_score_table(aft_row);
823 if (ret < 0)
824 return ret;
825 was_admissible = ret;
826 ret = compute_mood_score(aft_row, current_mood, &score);
827 is_admissible = (ret > 0);
828 if (!was_admissible && !is_admissible)
829 return 1;
830 if (was_admissible && !is_admissible)
831 return delete_from_statistics_and_score_table(aft_row);
832 if (!was_admissible && is_admissible) {
833 ret = add_afs_statistics(aft_row);
834 if (ret < 0)
835 return ret;
836 return add_to_score_table(aft_row, score);
837 }
838 /* update score */
839 ret = get_afsi_of_row(aft_row, &afsi);
840 if (ret < 0)
841 return ret;
842 if (old_afsi) {
843 ret = update_afs_statistics(old_afsi, &afsi);
844 if (ret < 0)
845 return ret;
846 }
847 score += compute_num_played_score(&afsi);
848 score += compute_last_played_score(&afsi);
849 score /= 3;
850 PARA_DEBUG_LOG("score: %li\n", score);
851 percent = (score + 100) / 3;
852 if (percent > 100)
853 percent = 100;
854 else if (percent < 0)
855 percent = 0;
856 PARA_DEBUG_LOG("re-inserting at %lu%%\n", percent);
857 return score_update(aft_row, percent);
858 }
859
860 static void log_statistics(void)
861 {
862 unsigned n = statistics.num;
863
864 if (!n) {
865 PARA_NOTICE_LOG("no admissible files\n");
866 return;
867 }
868 PARA_NOTICE_LOG("last_played mean: %lli, last_played sigma: %llu\n",
869 (long long int)(statistics.last_played_sum / n),
870 (long long unsigned)int_sqrt(statistics.last_played_qd / n));
871 PARA_NOTICE_LOG("num_played mean: %lli, num_played sigma: %llu\n",
872 (long long int)statistics.num_played_sum / n,
873 (long long unsigned)int_sqrt(statistics.num_played_qd / n));
874 }
875
876 /**
877 * Change the current mood.
878 *
879 * \param mood_name The name of the mood to open.
880 *
881 * There are two special cases: If \a mood_name is \a NULL, load the
882 * first available mood. If \a mood_name is the empty string "", load
883 * the dummy mood that accepts every audio file and uses a scoring method
884 * based only on the \a last_played information.
885 *
886 * If there is already an open mood, it will be closed first.
887 *
888 * \return Positive on success, negative on errors. Loading the dummy mood
889 * always succeeds.
890 *
891 * \sa struct admissible_file_info, struct admissible_array, struct
892 * afs_info::last_played, mood_close().
893 */
894 int change_current_mood(char *mood_name)
895 {
896 int i, ret;
897 struct admissible_array aa = {
898 .size = 0,
899 .array = NULL
900 };
901
902 if (!mood_name) {
903 struct mood *m;
904 ret = load_first_available_mood(&m);
905 if (ret < 0)
906 return ret;
907 destroy_mood(current_mood);
908 current_mood = m;
909 } else if (*mood_name) {
910 struct mood *m;
911 struct osl_row *row;
912 struct osl_object obj = {
913 .data = mood_name,
914 .size = strlen(mood_name) + 1
915 };
916 ret = osl_get_row(moods_table, BLOBCOL_NAME, &obj, &row);
917 if (ret < 0) {
918 PARA_NOTICE_LOG("no such mood: %s\n", mood_name);
919 return ret;
920 }
921 ret = load_mood(row, &m);
922 if (ret < 0)
923 return ret;
924 destroy_mood(current_mood);
925 current_mood = m;
926 } else {
927 destroy_mood(current_mood);
928 current_mood = alloc_new_mood("dummy");
929 }
930 aa.m = current_mood;
931 PARA_NOTICE_LOG("loaded mood %s\n", current_mood->name);
932 PARA_INFO_LOG("%s\n", "computing statistics of admissible files");
933 ret = audio_file_loop(&aa, add_if_admissible);
934 if (ret < 0)
935 return ret;
936 log_statistics();
937 PARA_NOTICE_LOG("%d admissible files \n", statistics.num);
938 for (i = 0; i < statistics.num; i++) {
939 struct admissible_file_info *a = aa.array + i;
940 ret = add_to_score_table(a->aft_row, a->score);
941 if (ret < 0)
942 goto out;
943 }
944 PARA_NOTICE_LOG("score add complete\n");
945 ret = 1;
946 out:
947 free(aa.array);
948 return ret;
949 }
950
951 /**
952 * Close the current mood.
953 *
954 * Free all resources of the current mood which were allocated during
955 * mood_open().
956 */
957 void close_current_mood(void)
958 {
959 destroy_mood(current_mood);
960 current_mood = NULL;
961 memset(&statistics, 0, sizeof(statistics));
962 }
963
964 /**
965 * Close and re-open the current mood.
966 *
967 * This function is used if changes to the audio file table or the
968 * attribute table were made that render the current list of admissible
969 * files useless. For example, if an attribute is removed from the
970 * attribute table, this function is called.
971 *
972 * \return Positive on success, negative on errors. If no mood is currently
973 * open, the function returns success.
974 *
975 * \sa mood_open(), mood_close().
976 */
977 int reload_current_mood(void)
978 {
979 int ret;
980 char *mood_name;
981
982 if (!current_mood)
983 return 1;
984 score_shutdown(0);
985 mood_name = para_strdup(current_mood->name);
986 close_current_mood();
987 ret = change_current_mood(mood_name);
988 free(mood_name);
989 return ret;
990 }