1dc401c9d37478d4dd47c440c664c203b096cd3e
[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, long *result)
265 {
266 struct mood_item *item;
267 int match = 0;
268 long score_arg_sum = 0, score = 0;
269
270 if (!current_mood)
271 return -E_NO_MOOD;
272 /* reject audio file if it matches any entry in the deny list */
273 list_for_each_entry(item, &current_mood->deny_list, mood_item_node)
274 if (add_item_score(aft_row, item, &score, &score_arg_sum) > 0)
275 return -E_NOT_ADMISSIBLE;
276 list_for_each_entry(item, &current_mood->accept_list, mood_item_node)
277 if (add_item_score(aft_row, item, &score, &score_arg_sum) > 0)
278 match = 1;
279 /* reject if there is no matching entry in the accept list */
280 if (!match && !list_empty(&current_mood->accept_list))
281 return -E_NOT_ADMISSIBLE;
282 list_for_each_entry(item, &current_mood->score_list, mood_item_node)
283 add_item_score(aft_row, item, &score, &score_arg_sum);
284 if (score_arg_sum)
285 score /= score_arg_sum;
286 *result = score;
287 return 1;
288 }
289
290 static const struct mood_method mood_methods[] = {
291 {
292 .parser = mm_played_rarely_parser,
293 .score_function = mm_played_rarely_score_function,
294 .name = "played_rarely"
295 },
296 {
297 .parser = mm_is_set_parser,
298 .score_function = mm_is_set_score_function,
299 .name = "is_set"
300 },
301 {
302 .parser = mm_name_like_parser,
303 .score_function = mm_name_like_score_function,
304 .cleanup = mm_name_like_cleanup,
305 .name = "name_like"
306 },
307 {
308 .parser = NULL
309 }
310 };
311
312 static void cleanup_list_entry(struct mood_item *item)
313 {
314 if (item->method && item->method->cleanup)
315 item->method->cleanup(item->parser_data);
316 else
317 free(item->parser_data);
318 list_del(&item->mood_item_node);
319 free(item);
320 }
321
322 static void destroy_mood(struct mood *m)
323 {
324 struct mood_item *tmp, *item;
325
326 if (!m)
327 return;
328 list_for_each_entry_safe(item, tmp, &m->accept_list, mood_item_node)
329 cleanup_list_entry(item);
330 list_for_each_entry_safe(item, tmp, &m->deny_list, mood_item_node)
331 cleanup_list_entry(item);
332 list_for_each_entry_safe(item, tmp, &m->score_list, mood_item_node)
333 cleanup_list_entry(item);
334 free(m->name);
335 free(m);
336 }
337
338 static struct mood *alloc_new_mood(const char *name)
339 {
340 struct mood *m = para_calloc(sizeof(struct mood));
341 m->name = para_strdup(name);
342 INIT_LIST_HEAD(&m->accept_list);
343 INIT_LIST_HEAD(&m->deny_list);
344 INIT_LIST_HEAD(&m->score_list);
345 return m;
346 }
347
348 /** The different types of a mood line. */
349 enum mood_line_type {
350 /** Invalid. */
351 ML_INVALID,
352 /** Accept line. */
353 ML_ACCEPT,
354 /** Deny line. */
355 ML_DENY,
356 /** Score line. */
357 ML_SCORE
358 };
359
360 /*
361 * <accept [with score <score>] | deny [with score <score>] | score <score>>
362 * [if] [not] <mood_method> [options]
363 * <score> is either an integer or "random" which assigns a random score to
364 * all matching files
365 */
366
367 static int parse_mood_line(char *mood_line, void *data)
368 {
369 struct mood *m = data;
370 char **argv;
371 char *delim = " \t";
372 unsigned num_words;
373 char **w;
374 int i, ret;
375 enum mood_line_type mlt = ML_INVALID;
376 struct mood_item *mi = NULL;
377 char *buf = para_strdup(mood_line);
378
379 num_words = split_args(buf, &argv, delim);
380 ret = 1;
381 if (!num_words) /* empty line */
382 goto out;
383 w = argv;
384 if (**w == '#') /* comment */
385 goto out;
386 if (!strcmp(*w, "accept"))
387 mlt = ML_ACCEPT;
388 else if (!strcmp(*w, "deny"))
389 mlt = ML_DENY;
390 else if (!strcmp(*w, "score"))
391 mlt = ML_SCORE;
392 ret = -E_MOOD_SYNTAX;
393 if (mlt == ML_INVALID)
394 goto out;
395 mi = para_calloc(sizeof(struct mood_item));
396 if (mlt != ML_SCORE) {
397 ret = -E_MOOD_SYNTAX;
398 w++;
399 if (!*w)
400 goto out;
401 if (!strcmp(*w, "with")) {
402 w++;
403 if (!*w)
404 goto out;
405 }
406 }
407 if (mlt == ML_SCORE || !strcmp(*w, "score")) {
408 ret = -E_MOOD_SYNTAX;
409 w++;
410 if (!*w)
411 goto out;
412 if (strcmp(*w, "random")) {
413 mi->random_score = 0;
414 ret = para_atol(*w, &mi->score_arg);
415 if (ret < 0)
416 goto out;
417 } else {
418 mi->random_score = 1;
419 if (!*(w + 1))
420 goto success; /* the line "score random" is valid */
421 }
422 } else
423 mi->score_arg = 0;
424 ret = -E_MOOD_SYNTAX;
425 w++;
426 if (!*w)
427 goto out;
428 if (!strcmp(*w, "if")) {
429 ret = -E_MOOD_SYNTAX;
430 w++;
431 if (!*w)
432 goto out;
433 }
434 if (!strcmp(*w, "not")) {
435 ret = -E_MOOD_SYNTAX;
436 w++;
437 if (!*w)
438 goto out;
439 mi->logical_not = 1;
440 } else
441 mi->logical_not = 0;
442 for (i = 0; mood_methods[i].parser; i++) {
443 if (strcmp(*w, mood_methods[i].name))
444 continue;
445 break;
446 }
447 ret = -E_MOOD_SYNTAX;
448 if (!mood_methods[i].parser)
449 goto out;
450 w++;
451 ret = mood_methods[i].parser(*w, &mi->parser_data);
452 if (ret < 0)
453 goto out;
454 mi->method = &mood_methods[i];
455 success:
456 if (mlt == ML_ACCEPT)
457 para_list_add(&mi->mood_item_node, &m->accept_list);
458 else if (mlt == ML_DENY)
459 para_list_add(&mi->mood_item_node, &m->deny_list);
460 else
461 para_list_add(&mi->mood_item_node, &m->score_list);
462 PARA_DEBUG_LOG("%s entry added, method: %p\n", mlt == ML_ACCEPT? "accept" :
463 (mlt == ML_DENY? "deny" : "score"), mi->method);
464 ret = 1;
465 out:
466 free(argv);
467 free(buf);
468 if (ret >= 0)
469 return ret;
470 if (mi) {
471 free(mi->parser_data);
472 free(mi);
473 }
474 return ret;
475 }
476
477 static int load_mood(const struct osl_row *row)
478 {
479 int ret;
480 struct mood *new_mood, *old_mood = current_mood;
481 struct osl_object objs[NUM_BLOB_COLUMNS];
482
483 ret = osl_get_object(moods_table, 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, row, BLOBCOL_DEF, &objs[BLOBCOL_DEF]);
489 if (ret < 0)
490 return ret;
491 new_mood = alloc_new_mood((char*)objs[BLOBCOL_NAME].data);
492 current_mood = new_mood;
493 ret = for_each_line_ro(objs[BLOBCOL_DEF].data, objs[BLOBCOL_DEF].size,
494 parse_mood_line, &current_mood);
495 osl_close_disk_object(&objs[BLOBCOL_DEF]);
496 if (ret < 0) {
497 PARA_ERROR_LOG("unable to load mood %s: %d\n",
498 (char *)objs[BLOBCOL_NAME].data, ret);
499 destroy_mood(new_mood);
500 current_mood = old_mood;
501 return ret;
502 }
503 destroy_mood(old_mood);
504 current_mood = new_mood;
505 PARA_INFO_LOG("loaded mood %s\n", current_mood->name);
506 return 1;
507 }
508
509 /* returns -E_MOOD_LOADED on _success_ to terminate the loop */
510 static int mood_loop(struct osl_row *row, __a_unused void *private_data)
511 {
512 int ret = load_mood(row);
513 if (ret < 0) {
514 if (ret != -E_DUMMY_ROW)
515 PARA_NOTICE_LOG("invalid mood (%d), trying next mood\n", ret);
516 return 1;
517 }
518 return -E_MOOD_LOADED;
519 }
520
521 static int load_first_available_mood(void)
522 {
523 int ret = osl_rbtree_loop(moods_table, BLOBCOL_NAME, NULL,
524 mood_loop);
525 if (ret == -E_MOOD_LOADED) /* success */
526 return 1;
527 if (ret < 0)
528 return ret; /* error */
529 PARA_NOTICE_LOG("no valid mood found\n");
530 return -E_NO_MOOD;
531 }
532
533 #if 0
534 static unsigned int_log2(uint64_t x)
535 {
536 unsigned res = 0;
537
538 while (x) {
539 x /= 2;
540 res++;
541 }
542 return res;
543 }
544 #endif
545
546 static int64_t normalized_value(int64_t x, int64_t n, int64_t sum, int64_t qd)
547 {
548 if (!n || !qd)
549 return 0;
550 return 100 * (n * x - sum) / (int64_t)int_sqrt(n * qd);
551 }
552
553 static long compute_num_played_score(struct afs_info *afsi)
554 {
555 return -normalized_value(afsi->num_played, statistics.num,
556 statistics.num_played_sum, statistics.num_played_qd);
557 }
558
559 static long compute_last_played_score(struct afs_info *afsi)
560 {
561 return -normalized_value(afsi->last_played, statistics.num,
562 statistics.last_played_sum, statistics.last_played_qd);
563 }
564
565 static long compute_dynamic_score(const struct osl_row *aft_row)
566 {
567 struct afs_info afsi;
568 int64_t score, nscore = 0, lscore = 0;
569 int ret;
570
571 ret = get_afsi_of_row(aft_row, &afsi);
572 if (ret < 0)
573 return -100;
574 nscore = compute_num_played_score(&afsi);
575 lscore = compute_last_played_score(&afsi);
576 score = nscore + lscore;
577 return score;
578 }
579
580 static int add_afs_statistics(const struct osl_row *row)
581 {
582 uint64_t n, x, s;
583 struct afs_info afsi;
584 int ret;
585
586 ret = get_afsi_of_row(row, &afsi);
587 if (ret < 0)
588 return ret;
589 n = statistics.num;
590 x = afsi.last_played;
591 s = statistics.last_played_sum;
592 if (n > 0)
593 statistics.last_played_qd += (x - s / n) * (x - s / n) * n / (n + 1);
594 statistics.last_played_sum += x;
595
596 x = afsi.num_played;
597 s = statistics.num_played_sum;
598 if (n > 0)
599 statistics.num_played_qd += (x - s / n) * (x - s / n) * n / (n + 1);
600 statistics.num_played_sum += x;
601 statistics.num++;
602 return 1;
603 }
604
605 static int del_afs_statistics(const struct osl_row *row)
606 {
607 uint64_t n, s, q, a, new_s;
608 struct afs_info afsi;
609 int ret;
610 ret = get_afsi_of_row(row, &afsi);
611 if (ret < 0)
612 return ret;
613 n = statistics.num;
614 assert(n);
615 if (n == 1) {
616 memset(&statistics, 0, sizeof(statistics));
617 return 1;
618 }
619
620 s = statistics.last_played_sum;
621 q = statistics.last_played_qd;
622 a = afsi.last_played;
623 new_s = s - a;
624 statistics.last_played_sum = new_s;
625 statistics.last_played_qd = q + s * s / n - a * a
626 - new_s * new_s / (n - 1);
627
628 s = statistics.num_played_sum;
629 q = statistics.num_played_qd;
630 a = afsi.num_played;
631 new_s = s - a;
632 statistics.num_played_sum = new_s;
633 statistics.num_played_qd = q + s * s / n - a * a
634 - new_s * new_s / (n - 1);
635
636 statistics.num--;
637 return 1;
638 }
639
640 /**
641 * Structure used during mood_open().
642 *
643 * At mood open time, we look at each file in the audio file table in order to
644 * determine whether it is admissible. If a file happens to be admissible, its
645 * mood score is computed by calling each relevant mood_score_function. Next,
646 * we update the afs_statistics and add a struct admissible_file_info to a
647 * temporary array.
648 *
649 * If all files have been processed that way, the final score of each
650 * admissible file is computed by adding the dynamic score (which depends on
651 * the afs_statistics) to the mood score. Finally, all audio files in the
652 * array are added to the score table and the admissible array is freed.
653 *
654 * \sa mood_method, admissible_array.
655 */
656 struct admissible_file_info
657 {
658 /** The admissible audio file. */
659 struct osl_row *aft_row;
660 /** Its score. */
661 long score;
662 };
663
664 /** The temporary array of admissible files. */
665 struct admissible_array {
666 /** The size of the array */
667 unsigned size;
668 /** Pointer to the array of admissible files. */
669 struct admissible_file_info *array;
670 };
671
672 /**
673 * Add an entry to the array of admissible files.
674 *
675 * \param aft_row The audio file to be added.
676 * \param private_data Pointer to a struct admissible_file_info.
677 *
678 * \return Negative on errors, positive on success.
679 */
680 static int add_if_admissible(struct osl_row *aft_row, void *private_data)
681 {
682 int ret;
683 struct admissible_array *aa = private_data;
684 long score = 0;
685
686 score = 0;
687 ret = compute_mood_score(aft_row, &score);
688 if (ret < 0)
689 return (ret == -E_NOT_ADMISSIBLE)? 1 : ret;
690 if (statistics.num >= aa->size) {
691 aa->size *= 2;
692 aa->size += 100;
693 aa->array = para_realloc(aa->array,
694 aa->size * sizeof(struct admissible_file_info));
695 }
696 aa->array[statistics.num].aft_row = aft_row;
697 aa->array[statistics.num].score = score;
698 ret = add_afs_statistics(aft_row);
699 if (ret < 0)
700 return ret;
701 return 1;
702 }
703
704 /**
705 * Compute the new quadratic deviation in case one element changes.
706 *
707 * \param n Number of elements.
708 * \param old_qd The quadratic deviation before the change.
709 * \param old_val The value that was repaced.
710 * \param new_val The replacement value.
711 * \param old_sum The sum of all elements before the update.
712 *
713 * \return The new quadratic deviation resulting from replacing old_val
714 * by new_val.
715 *
716 * Given n real numbers a_1, ..., a_n, their sum S = a_1 + ... + a_n,
717 * their quadratic deviation
718 *
719 * q = (a_1 - S/n)^2 + ... + (a_n - S/n)^2,
720 *
721 * and a real number b, the quadratic deviation q' of a_1,...a_{n-1}, b (ie.
722 * the last number a_n was replaced by b) may be computed in O(1) time in terms
723 * of n, q, a_n, b, and S as
724 *
725 * q' = q + d * s - (2 * S + d) * d / n,
726 *
727 * where d = b - a_n, and s = b + a_n.
728 *
729 * Example: n = 3, a_1 = 3, a_2 = 5, a_3 = 7, b = 10. Then S = 15, q = 8, d = 3,
730 * s = 17, so
731 *
732 * q + d * s - (2 * S + d) * d / n = 8 + 51 - 33 = 26,
733 *
734 * which equals q' = (3 - 6)^2 + (5 - 6)^2 + (10 - 6)^2.
735 *
736 */
737 _static_inline_ int64_t update_quadratic_deviation(int64_t n, int64_t old_qd,
738 int64_t old_val, int64_t new_val, int64_t old_sum)
739 {
740 int64_t delta = new_val - old_val;
741 int64_t sigma = new_val + old_val;
742 return old_qd + delta * sigma - (2 * old_sum + delta) * delta / n;
743 }
744
745 static int update_afs_statistics(struct afs_info *old_afsi, struct afs_info *new_afsi)
746 {
747 unsigned n;
748 int ret = get_num_admissible_files(&n);
749
750 if (ret < 0)
751 return ret;
752 assert(n);
753
754 statistics.last_played_qd = update_quadratic_deviation(n,
755 statistics.last_played_qd, old_afsi->last_played,
756 new_afsi->last_played, statistics.last_played_sum);
757 statistics.last_played_sum += new_afsi->last_played - old_afsi->last_played;
758
759 statistics.num_played_qd = update_quadratic_deviation(n,
760 statistics.num_played_qd, old_afsi->num_played,
761 new_afsi->num_played, statistics.num_played_sum);
762 statistics.num_played_sum += new_afsi->num_played - old_afsi->num_played;
763 return 1;
764 }
765
766 static int add_to_score_table(const struct osl_row *aft_row, long mood_score)
767 {
768 long score = (compute_dynamic_score(aft_row) + mood_score) / 3;
769 return score_add(aft_row, score);
770 }
771
772 static int delete_from_statistics_and_score_table(const struct osl_row *aft_row)
773 {
774 int ret = del_afs_statistics(aft_row);
775 if (ret < 0)
776 return ret;
777 return score_delete(aft_row);
778 }
779
780 /**
781 * Delete one entry from the statitics and from the score table.
782 *
783 * \param aft_row The audio file which is no longer admissible.
784 *
785 * \return Positive on success, negative on errors.
786 *
787 * \sa score_delete(), mood_update_audio_file().
788 */
789 int mood_delete_audio_file(const struct osl_row *aft_row)
790 {
791 int ret;
792
793 ret = row_belongs_to_score_table(aft_row);
794 if (ret < 0)
795 return ret;
796 if (!ret) /* not admissible, nothing to do */
797 return 1;
798 return delete_from_statistics_and_score_table(aft_row);
799 }
800
801 /**
802 * Compute the new score of an audio file.
803 *
804 * \param aft_row Determines the audio file.
805 * \param old_afsi The audio file selector info before updating.
806 *
807 * The \a old_afsi argument may be \p NULL which indicates that no changes to
808 * the audio file info were made.
809 *
810 * \return Positive on success, negative on errors.
811 */
812 int mood_update_audio_file(const struct osl_row *aft_row, struct afs_info *old_afsi)
813 {
814 long score, percent;
815 int ret, is_admissible, was_admissible = 0;
816 struct afs_info afsi;
817
818 if (!current_mood)
819 return 1; /* nothing to do */
820 ret = row_belongs_to_score_table(aft_row);
821 if (ret < 0)
822 return ret;
823 was_admissible = ret;
824 ret = compute_mood_score(aft_row, &score);
825 is_admissible = (ret > 0);
826 if (!was_admissible && !is_admissible)
827 return 1;
828 if (was_admissible && !is_admissible)
829 return delete_from_statistics_and_score_table(aft_row);
830 if (!was_admissible && is_admissible) {
831 ret = add_afs_statistics(aft_row);
832 if (ret < 0)
833 return ret;
834 return add_to_score_table(aft_row, score);
835 }
836 /* update score */
837 ret = get_afsi_of_row(aft_row, &afsi);
838 if (ret < 0)
839 return ret;
840 if (old_afsi) {
841 ret = update_afs_statistics(old_afsi, &afsi);
842 if (ret < 0)
843 return ret;
844 }
845 score += compute_num_played_score(&afsi);
846 score += compute_last_played_score(&afsi);
847 score /= 3;
848 PARA_DEBUG_LOG("score: %li\n", score);
849 percent = (score + 100) / 3;
850 if (percent > 100)
851 percent = 100;
852 else if (percent < 0)
853 percent = 0;
854 PARA_DEBUG_LOG("re-inserting at %lu%%\n", percent);
855 return score_update(aft_row, percent);
856 }
857
858 static void log_statistics(void)
859 {
860 unsigned n = statistics.num;
861
862 if (!n) {
863 PARA_NOTICE_LOG("no admissible files\n");
864 return;
865 }
866 PARA_NOTICE_LOG("last_played mean: %lli, last_played sigma: %llu\n",
867 (long long int)(statistics.last_played_sum / n),
868 (long long unsigned)int_sqrt(statistics.last_played_qd / n));
869 PARA_NOTICE_LOG("num_played mean: %lli, num_played sigma: %llu\n",
870 (long long int)statistics.num_played_sum / n,
871 (long long unsigned)int_sqrt(statistics.num_played_qd / n));
872 }
873
874 /**
875 * Open the given mood.
876 *
877 * \param mood_name The name of the mood to open.
878 *
879 * There are two special cases: If \a mood_name is \a NULL, load the
880 * first available mood. If \a mood_name is the empty string "", load
881 * the dummy mood that accepts every audio file and uses a scoring method
882 * based only on the \a last_played information.
883 *
884 * \return Positive on success, negative on errors. Loading the dummy mood
885 * always succeeds.
886 *
887 * \sa struct admissible_file_info, struct admissible_array, struct
888 * afs_info::last_played, mood_close().
889 */
890 int mood_open(char *mood_name)
891 {
892 int i, ret;
893 struct admissible_array aa = {
894 .size = 0,
895 .array = NULL
896 };
897
898 if (!mood_name) {
899 ret = load_first_available_mood();
900 if (ret < 0)
901 return ret;
902 } else if (*mood_name) {
903 struct osl_row *row;
904 struct osl_object obj = {
905 .data = mood_name,
906 .size = strlen(mood_name) + 1
907 };
908 ret = osl_get_row(moods_table, BLOBCOL_NAME, &obj, &row);
909 if (ret < 0) {
910 PARA_NOTICE_LOG("no such mood: %s\n", mood_name);
911 return ret;
912 }
913 ret = load_mood(row);
914 if (ret < 0)
915 return ret;
916 } else {
917 destroy_mood(current_mood);
918 current_mood = alloc_new_mood("dummy");
919 }
920 PARA_NOTICE_LOG("loaded mood %s\n", current_mood->name);
921 PARA_INFO_LOG("%s\n", "computing statistics of admissible files");
922 ret = audio_file_loop(&aa, add_if_admissible);
923 if (ret < 0)
924 return ret;
925 log_statistics();
926 PARA_NOTICE_LOG("%d admissible files \n", statistics.num);
927 for (i = 0; i < statistics.num; i++) {
928 struct admissible_file_info *a = aa.array + i;
929 ret = add_to_score_table(a->aft_row, a->score);
930 if (ret < 0)
931 goto out;
932 }
933 PARA_NOTICE_LOG("score add complete\n");
934 ret = 1;
935 out:
936 free(aa.array);
937 return ret;
938 }
939
940 /**
941 * Close the current mood.
942 *
943 * Free all resources of the current mood which were allocated during
944 * mood_open().
945 */
946 void mood_close(void)
947 {
948 destroy_mood(current_mood);
949 current_mood = NULL;
950 memset(&statistics, 0, sizeof(statistics));
951 }
952
953 /**
954 * Close and re-open the current mood.
955 *
956 * This function is used if changes to the audio file table or the
957 * attribute table were made that render the current list of admissible
958 * files useless. For example, if an attribute is removed from the
959 * attribute table, this function is called.
960 *
961 * \return Positive on success, negative on errors. If no mood is currently
962 * open, the function returns success.
963 *
964 * \sa mood_open(), mood_close().
965 */
966 int mood_reload(void)
967 {
968 int ret;
969 char *mood_name;
970
971 if (!current_mood)
972 return 1;
973 score_shutdown(0);
974 mood_name = para_strdup(current_mood->name);
975 mood_close();
976 ret = mood_open(mood_name);
977 free(mood_name);
978 return ret;
979 }