mood.c: Add no_attributes_set mood method.
[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 <fnmatch.h>
10 #include "para.h"
11 #include "error.h"
12 #include "afh.h"
13 #include "afs.h"
14 #include "list.h"
15 #include "string.h"
16
17 /**
18 * Contains statistical data of the currently admissible audio files.
19 *
20 * It is used to assign normalized score values to each admissible audio file.
21 */
22 struct afs_statistics {
23 /** Sum of num played over all admissible files. */
24 int64_t num_played_sum;
25 /** Sum of last played times over all admissible files. */
26 int64_t last_played_sum;
27 /** Quadratic deviation of num played time. */
28 int64_t num_played_qd;
29 /** Quadratic deviation of last played time. */
30 int64_t last_played_qd;
31 /** Number of admissible files */
32 unsigned num;
33 };
34 struct afs_statistics statistics;
35
36 /**
37 * Assign scores according to a mood_method.
38 *
39 * Each mood_method has its own mood_score_function. The first parameter passed
40 * to that function is a pointer to a row of the audio file table. It
41 * determines the audio file for which a score is to be assigned. The second
42 * argument depends on the mood method this function is used for. It usually is
43 * the argument given at the end of a mood line.
44 *
45 * Mood score functions must return values between -100 and +100 inclusively.
46 * Boolean score functions should always return either -100 or +100.
47 *
48 * \sa struct mood_method, mood_parser.
49 */
50 typedef int mood_score_function(const char *path, const struct afs_info *afsi,
51 const struct audio_format_info *afhi, const void *data);
52
53 /**
54 * Pre-process a mood line.
55 *
56 * The mood_parser of a mood_method is called once at mood open time for each
57 * line of the current mood definition that contains the mood_method's name as
58 * a keyword. The line is passed to the mood_parser as the first argument. The
59 * mood_parser must determine whether the line is syntactically correct and
60 * return a positive value if so and a negative value otherwise.
61 *
62 * Some mood parsers pre-process the data given in the mood line to compute a
63 * structure which depends of the particular mood_method and which is used
64 * later in the mood_score_function of the mood_method. The mood_parser may
65 * store a pointer to its structure via the second argument.
66 *
67 * \sa mood_open(), mood_cleanup_function, mood_score_function.
68 */
69 typedef int mood_parser(const char *, void **);
70
71 /**
72 * Deallocate resources which were allocated by the mood_parser.
73 *
74 * This optional function of a mood_method is used to free any resources
75 * allocated in mood_open() by the mood_parser. The argument passed is a
76 * pointer to the mood_method specific data structure that was returned by the
77 * mood_parser.
78 *
79 * \sa mood_parser.
80 */
81 typedef void mood_cleanup_function(void *);
82
83 /**
84 * Used for scoring and to determine whether a file is admissible.
85 */
86 struct mood_method {
87 /* The name of the method. */
88 const char *name;
89 /** Pointer to the mood parser. */
90 mood_parser *parser;
91 /** Pointer to the score function */
92 mood_score_function *score_function;
93 /** Optional cleanup function. */
94 mood_cleanup_function *cleanup;
95 };
96
97 /**
98 * Each line of the current mood corresponds to a mood_item.
99 */
100 struct mood_item {
101 /** The method this line is referring to. */
102 const struct mood_method *method;
103 /** The data structure computed by the mood parser. */
104 void *parser_data;
105 /** The given score value, or zero if none was given. */
106 int32_t score_arg;
107 /** Non-zero if random scoring was requested. */
108 int random_score;
109 /** Whether the "not" keyword was given in the mood line. */
110 int logical_not;
111 /** The position in the list of items. */
112 struct list_head mood_item_node;
113 };
114
115 /**
116 * Created from the mood definition by mood_open().
117 *
118 * When a mood is opened, each line of its definition is investigated, and a
119 * corresponding mood item is produced. Each mood line starts with \p accept,
120 * \p deny, or \p score which determines the type of the mood line. For each
121 * such type a linked list is maintained whose entries are the mood items.
122 *
123 * \sa mood_item, mood_open().
124 */
125 struct mood {
126 /** The name of this mood. */
127 char *name;
128 /** The list of mood items of type \p accept. */
129 struct list_head accept_list;
130 /** The list of mood items of type \p deny. */
131 struct list_head deny_list;
132 /** The list of mood items of type \p score. */
133 struct list_head score_list;
134 };
135
136 static struct mood *current_mood;
137
138 /**
139 * Rough approximation to sqrt.
140 *
141 * \param x Integer of which to calculate the sqrt.
142 *
143 * \return An integer res with res * res <= x.
144 */
145 static uint64_t int_sqrt(uint64_t x)
146 {
147 uint64_t op, res, one = 1;
148 op = x;
149 res = 0;
150
151 one = one << 62;
152 while (one > op)
153 one >>= 2;
154
155 while (one != 0) {
156 if (op >= res + one) {
157 op = op - (res + one);
158 res = res + 2 * one;
159 }
160 res /= 2;
161 one /= 4;
162 }
163 // PARA_NOTICE_LOG("sqrt(%llu) = %llu\n", x, res);
164 return res;
165 }
166
167 static int mm_no_attributes_set_parser(const char *arg, __a_unused void **ignored)
168 {
169 if (arg && *arg)
170 PARA_WARNING_LOG("ignored junk at eol: %s\n", arg);
171 return 1;
172 }
173
174 static int mm_no_attributes_set_score_function(__a_unused const char *path,
175 const struct afs_info *afsi,
176 __a_unused const struct audio_format_info *afhi,
177 __a_unused const void *data)
178 {
179 if (!strcmp(path, "/home/mp3/checked/dvd_08/cd_52/Sade__Paradise.mp3"))
180 PARA_NOTICE_LOG("%s: %llu\n", path, afsi->attributes);
181 if (!afsi->attributes)
182 return 100;
183 return -100;
184 }
185
186 static int mm_played_rarely_score_function(__a_unused const char *path,
187 const struct afs_info *afsi,
188 __a_unused const struct audio_format_info *afhi,
189 __a_unused const void *data)
190 {
191 unsigned num;
192 int ret = get_num_admissible_files(&num);
193
194 if (ret < 0)
195 return 0;
196 if (statistics.num_played_sum - num * afsi->num_played
197 > int_sqrt(statistics.num_played_qd * num))
198 return 100;
199 return -100;
200 }
201
202 static int mm_played_rarely_parser(const char *arg, __a_unused void **ignored)
203 {
204 if (arg && *arg)
205 PARA_WARNING_LOG("ignored junk at eol: %s\n", arg);
206 return 1;
207 }
208
209 static int mm_name_like_score_function(const char *path,
210 __a_unused const struct afs_info *afsi,
211 __a_unused const struct audio_format_info *afhi,
212 const void *data)
213 {
214 if (fnmatch(data, path, 0))
215 return -100;
216 return 100;
217 }
218
219 static int mm_name_like_parser(const char *arg, void **data)
220 {
221 *data = para_strdup(arg);
222 return 1;
223 }
224
225 static void mm_name_like_cleanup(void *data)
226 {
227 free(data);
228 }
229
230 static int mm_is_set_parser(const char *arg, void **bitnum)
231 {
232 unsigned char *c = para_malloc(1);
233 int ret = get_attribute_bitnum_by_name(arg, c);
234
235 if (ret >= 0)
236 *bitnum = c;
237 else
238 free(c);
239 return ret;
240 }
241
242 static int mm_is_set_score_function(__a_unused const char *path,
243 __a_unused const struct afs_info *afsi,
244 __a_unused const struct audio_format_info *afhi,
245 const void *data)
246 {
247 const unsigned char *bn = data;
248 if (afsi->attributes & (1ULL << *bn))
249 return 100;
250 return -100;
251 }
252
253 /* returns 1 if row matches score item, negative otherwise */
254 static int add_item_score(const struct osl_row *row, struct mood_item *item, long *score,
255 long *score_arg_sum)
256 {
257 struct afs_info afsi;
258 struct audio_format_info afhi;
259 char *path;
260 int ret;
261
262 *score_arg_sum += item->random_score? 100 : PARA_ABS(item->score_arg);
263 ret = 100;
264 if (item->method) {
265 ret = get_afsi_of_row(row, &afsi);
266 if (ret< 0)
267 return ret;
268 ret = get_afhi_of_row(row, &afhi);
269 if (ret< 0)
270 return ret;
271 ret = get_audio_file_path_of_row(row, &path);
272 if (ret< 0)
273 return ret;
274 ret = item->method->score_function(path, &afsi, &afhi,
275 item->parser_data);
276 if ((ret < 0 && !item->logical_not) || (ret >= 0 && item->logical_not))
277 return -1; /* no match */
278 }
279 if (item->random_score)
280 *score += PARA_ABS(ret) * para_random(100);
281 else
282 *score += PARA_ABS(ret) * item->score_arg;
283 return 1;
284 }
285
286 static int compute_mood_score(const struct osl_row *aft_row, struct mood *m,
287 long *result)
288 {
289 struct mood_item *item;
290 int match = 0;
291 long score_arg_sum = 0, score = 0;
292
293 if (!m)
294 return -E_NO_MOOD;
295 /* reject audio file if it matches any entry in the deny list */
296 list_for_each_entry(item, &m->deny_list, mood_item_node)
297 if (add_item_score(aft_row, item, &score, &score_arg_sum) > 0)
298 return -E_NOT_ADMISSIBLE;
299 list_for_each_entry(item, &m->accept_list, mood_item_node)
300 if (add_item_score(aft_row, item, &score, &score_arg_sum) > 0)
301 match = 1;
302 /* reject if there is no matching entry in the accept list */
303 if (!match && !list_empty(&m->accept_list))
304 return -E_NOT_ADMISSIBLE;
305 list_for_each_entry(item, &m->score_list, mood_item_node)
306 add_item_score(aft_row, item, &score, &score_arg_sum);
307 if (score_arg_sum)
308 score /= score_arg_sum;
309 *result = score;
310 return 1;
311 }
312
313 static const struct mood_method mood_methods[] = {
314 {
315 .parser = mm_no_attributes_set_parser,
316 .score_function = mm_no_attributes_set_score_function,
317 .name = "no_attributes_set"
318 },
319 {
320 .parser = mm_played_rarely_parser,
321 .score_function = mm_played_rarely_score_function,
322 .name = "played_rarely"
323 },
324 {
325 .parser = mm_is_set_parser,
326 .score_function = mm_is_set_score_function,
327 .name = "is_set"
328 },
329 {
330 .parser = mm_name_like_parser,
331 .score_function = mm_name_like_score_function,
332 .cleanup = mm_name_like_cleanup,
333 .name = "name_like"
334 },
335 {
336 .parser = NULL
337 }
338 };
339
340 static void cleanup_list_entry(struct mood_item *item)
341 {
342 if (item->method && item->method->cleanup)
343 item->method->cleanup(item->parser_data);
344 else
345 free(item->parser_data);
346 list_del(&item->mood_item_node);
347 free(item);
348 }
349
350 static void destroy_mood(struct mood *m)
351 {
352 struct mood_item *tmp, *item;
353
354 if (!m)
355 return;
356 list_for_each_entry_safe(item, tmp, &m->accept_list, mood_item_node)
357 cleanup_list_entry(item);
358 list_for_each_entry_safe(item, tmp, &m->deny_list, mood_item_node)
359 cleanup_list_entry(item);
360 list_for_each_entry_safe(item, tmp, &m->score_list, mood_item_node)
361 cleanup_list_entry(item);
362 free(m->name);
363 free(m);
364 }
365
366 static struct mood *alloc_new_mood(const char *name)
367 {
368 struct mood *m = para_calloc(sizeof(struct mood));
369 m->name = para_strdup(name);
370 INIT_LIST_HEAD(&m->accept_list);
371 INIT_LIST_HEAD(&m->deny_list);
372 INIT_LIST_HEAD(&m->score_list);
373 return m;
374 }
375
376 /** The different types of a mood line. */
377 enum mood_line_type {
378 /** Invalid. */
379 ML_INVALID,
380 /** Accept line. */
381 ML_ACCEPT,
382 /** Deny line. */
383 ML_DENY,
384 /** Score line. */
385 ML_SCORE
386 };
387
388 struct mood_line_parser_data {
389 struct mood *m;
390 unsigned line_num;
391 };
392
393 /*
394 * <accept [with score <score>] | deny [with score <score>] | score <score>>
395 * [if] [not] <mood_method> [options]
396 * <score> is either an integer or "random" which assigns a random score to
397 * all matching files
398 */
399
400 static int parse_mood_line(char *mood_line, void *data)
401 {
402 struct mood_line_parser_data *mlpd = data;
403 char **argv;
404 char *delim = " \t";
405 unsigned num_words;
406 char **w;
407 int i, ret;
408 enum mood_line_type mlt = ML_INVALID;
409 struct mood_item *mi = NULL;
410 char *buf = para_strdup(mood_line);
411
412 mlpd->line_num++;
413 num_words = split_args(buf, &argv, delim);
414 ret = 1;
415 if (!num_words) /* empty line */
416 goto out;
417 w = argv;
418 if (**w == '#') /* comment */
419 goto out;
420 if (!strcmp(*w, "accept"))
421 mlt = ML_ACCEPT;
422 else if (!strcmp(*w, "deny"))
423 mlt = ML_DENY;
424 else if (!strcmp(*w, "score"))
425 mlt = ML_SCORE;
426 ret = -E_MOOD_SYNTAX;
427 if (mlt == ML_INVALID)
428 goto out;
429 mi = para_calloc(sizeof(struct mood_item));
430 if (mlt != ML_SCORE) {
431 ret = -E_MOOD_SYNTAX;
432 w++;
433 if (!*w)
434 goto out;
435 if (!strcmp(*w, "with")) {
436 w++;
437 if (!*w)
438 goto out;
439 }
440 }
441 if (mlt == ML_SCORE || !strcmp(*w, "score")) {
442 ret = -E_MOOD_SYNTAX;
443 w++;
444 if (!*w)
445 goto out;
446 if (strcmp(*w, "random")) {
447 mi->random_score = 0;
448 ret = para_atoi32(*w, &mi->score_arg);
449 if (ret < 0)
450 goto out;
451 } else {
452 mi->random_score = 1;
453 if (!*(w + 1))
454 goto success; /* the line "score random" is valid */
455 }
456 } else
457 mi->score_arg = 0;
458 ret = -E_MOOD_SYNTAX;
459 w++;
460 if (!*w)
461 goto out;
462 if (!strcmp(*w, "if")) {
463 ret = -E_MOOD_SYNTAX;
464 w++;
465 if (!*w)
466 goto out;
467 }
468 if (!strcmp(*w, "not")) {
469 ret = -E_MOOD_SYNTAX;
470 w++;
471 if (!*w)
472 goto out;
473 mi->logical_not = 1;
474 } else
475 mi->logical_not = 0;
476 for (i = 0; mood_methods[i].parser; i++) {
477 if (strcmp(*w, mood_methods[i].name))
478 continue;
479 break;
480 }
481 ret = -E_MOOD_SYNTAX;
482 if (!mood_methods[i].parser)
483 goto out;
484 w++;
485 ret = mood_methods[i].parser(*w, &mi->parser_data);
486 if (ret < 0)
487 goto out;
488 mi->method = &mood_methods[i];
489 success:
490 if (mlpd->m) {
491 if (mlt == ML_ACCEPT)
492 para_list_add(&mi->mood_item_node, &mlpd->m->accept_list);
493 else if (mlt == ML_DENY)
494 para_list_add(&mi->mood_item_node, &mlpd->m->deny_list);
495 else
496 para_list_add(&mi->mood_item_node, &mlpd->m->score_list);
497 }
498 PARA_DEBUG_LOG("%s entry added, method: %p\n", mlt == ML_ACCEPT? "accept" :
499 (mlt == ML_DENY? "deny" : "score"), mi->method);
500 ret = 1;
501 out:
502 free(argv);
503 free(buf);
504 if (ret >= 0)
505 return ret;
506 if (mi) {
507 free(mi->parser_data);
508 free(mi);
509 }
510 return ret;
511 }
512
513 static int load_mood(const struct osl_row *mood_row, struct mood **m)
514 {
515 char *mood_name;
516 struct osl_object mood_def;
517 struct mood_line_parser_data mlpd = {.line_num = 0};
518 int ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
519
520 if (ret < 0)
521 return ret;
522 if (!*mood_name)
523 return -E_DUMMY_ROW;
524 mlpd.m = alloc_new_mood(mood_name);
525 ret = for_each_line_ro(mood_def.data, mood_def.size,
526 parse_mood_line, &mlpd);
527 osl_close_disk_object(&mood_def);
528 if (ret < 0) {
529 PARA_ERROR_LOG("unable to load mood %s: %s\n", mlpd.m->name,
530 PARA_STRERROR(-ret));
531 destroy_mood(mlpd.m);
532 return ret;
533 }
534 PARA_INFO_LOG("loaded mood %s\n", mlpd.m->name);
535 *m = mlpd.m;
536 return 1;
537 }
538
539 /*
540 * Calls load_mood() and reverts its error value: It returns -E_MOOD_LOADED
541 * on _success_, and 1 on errors. This way the loop over all moods stops at the
542 * first valid mood.
543 */
544 static int load_mood_loop_func(struct osl_row *mood_row, void *data)
545 {
546 struct mood **m = data;
547 int ret = load_mood(mood_row, m);
548 if (ret < 0) {
549 if (ret != -E_DUMMY_ROW)
550 PARA_NOTICE_LOG("invalid mood (%d), trying next mood\n", ret);
551 return 1;
552 }
553 return -E_MOOD_LOADED;
554 }
555
556 static int load_first_available_mood(struct mood **m)
557 {
558 int ret = osl_rbtree_loop(moods_table, BLOBCOL_NAME, m,
559 load_mood_loop_func);
560 if (ret == -E_MOOD_LOADED) /* success */
561 return 1;
562 if (ret < 0)
563 return ret; /* error */
564 PARA_NOTICE_LOG("no valid mood found\n");
565 return -E_NO_MOOD;
566 }
567
568 static int check_mood(struct osl_row *mood_row, void *data)
569 {
570 struct para_buffer *pb = data;
571 char *mood_name;
572 struct osl_object mood_def;
573 struct mood_line_parser_data mlpd = {.line_num = 0};
574
575 int ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
576
577 if (ret < 0) {
578 para_printf(pb, "failed to get mood definition\n");
579 return ret;
580 }
581 if (!*mood_name) /* ignore dummy row */
582 goto out;
583 para_printf(pb, "checking mood %s...\n", mood_name);
584 ret = for_each_line_ro(mood_def.data, mood_def.size,
585 parse_mood_line, &mlpd);
586 if (ret < 0)
587 para_printf(pb, "%s line %u: %s\n", mood_name, mlpd.line_num,
588 PARA_STRERROR(-ret));
589 out:
590 osl_close_disk_object(&mood_def);
591 return 1;
592 }
593
594 /**
595 * Check all moods for syntax errors.
596 *
597 * \param query Unused.
598 * \param result: Contains check messages.
599 */
600 int mood_check_callback(__a_unused const struct osl_object *query,
601 struct osl_object *result)
602 {
603 struct para_buffer pb = {.buf = NULL};
604
605 para_printf(&pb, "checking moods...\n");
606 osl_rbtree_loop(moods_table, BLOBCOL_ID, &pb,
607 check_mood);
608 result->data = pb.buf;
609 result->size = pb.size;
610 return 1;
611 }
612
613 #if 0
614 static unsigned int_log2(uint64_t x)
615 {
616 unsigned res = 0;
617
618 while (x) {
619 x /= 2;
620 res++;
621 }
622 return res;
623 }
624 #endif
625
626 static int64_t normalized_value(int64_t x, int64_t n, int64_t sum, int64_t qd)
627 {
628 if (!n || !qd)
629 return 0;
630 return 100 * (n * x - sum) / (int64_t)int_sqrt(n * qd);
631 }
632
633 static long compute_num_played_score(struct afs_info *afsi)
634 {
635 return -normalized_value(afsi->num_played, statistics.num,
636 statistics.num_played_sum, statistics.num_played_qd);
637 }
638
639 static long compute_last_played_score(struct afs_info *afsi)
640 {
641 return -normalized_value(afsi->last_played, statistics.num,
642 statistics.last_played_sum, statistics.last_played_qd);
643 }
644
645 static long compute_dynamic_score(const struct osl_row *aft_row)
646 {
647 struct afs_info afsi;
648 int64_t score, nscore = 0, lscore = 0;
649 int ret;
650
651 ret = get_afsi_of_row(aft_row, &afsi);
652 if (ret < 0)
653 return -100;
654 nscore = compute_num_played_score(&afsi);
655 lscore = compute_last_played_score(&afsi);
656 score = nscore + lscore;
657 return score;
658 }
659
660 static int add_afs_statistics(const struct osl_row *row)
661 {
662 uint64_t n, x, s;
663 struct afs_info afsi;
664 int ret;
665
666 ret = get_afsi_of_row(row, &afsi);
667 if (ret < 0)
668 return ret;
669 n = statistics.num;
670 x = afsi.last_played;
671 s = statistics.last_played_sum;
672 if (n > 0)
673 statistics.last_played_qd += (x - s / n) * (x - s / n) * n / (n + 1);
674 statistics.last_played_sum += x;
675
676 x = afsi.num_played;
677 s = statistics.num_played_sum;
678 if (n > 0)
679 statistics.num_played_qd += (x - s / n) * (x - s / n) * n / (n + 1);
680 statistics.num_played_sum += x;
681 statistics.num++;
682 return 1;
683 }
684
685 static int del_afs_statistics(const struct osl_row *row)
686 {
687 uint64_t n, s, q, a, new_s;
688 struct afs_info afsi;
689 int ret;
690 ret = get_afsi_of_row(row, &afsi);
691 if (ret < 0)
692 return ret;
693 n = statistics.num;
694 assert(n);
695 if (n == 1) {
696 memset(&statistics, 0, sizeof(statistics));
697 return 1;
698 }
699
700 s = statistics.last_played_sum;
701 q = statistics.last_played_qd;
702 a = afsi.last_played;
703 new_s = s - a;
704 statistics.last_played_sum = new_s;
705 statistics.last_played_qd = q + s * s / n - a * a
706 - new_s * new_s / (n - 1);
707
708 s = statistics.num_played_sum;
709 q = statistics.num_played_qd;
710 a = afsi.num_played;
711 new_s = s - a;
712 statistics.num_played_sum = new_s;
713 statistics.num_played_qd = q + s * s / n - a * a
714 - new_s * new_s / (n - 1);
715
716 statistics.num--;
717 return 1;
718 }
719
720 /**
721 * Structure used during mood_open().
722 *
723 * At mood open time, we look at each file in the audio file table in order to
724 * determine whether it is admissible. If a file happens to be admissible, its
725 * mood score is computed by calling each relevant mood_score_function. Next,
726 * we update the afs_statistics and add a struct admissible_file_info to a
727 * temporary array.
728 *
729 * If all files have been processed that way, the final score of each
730 * admissible file is computed by adding the dynamic score (which depends on
731 * the afs_statistics) to the mood score. Finally, all audio files in the
732 * array are added to the score table and the admissible array is freed.
733 *
734 * \sa mood_method, admissible_array.
735 */
736 struct admissible_file_info
737 {
738 /** The admissible audio file. */
739 struct osl_row *aft_row;
740 /** Its score. */
741 long score;
742 };
743
744 /** The temporary array of admissible files. */
745 struct admissible_array {
746 /** Files are admissible wrt. this mood. */
747 struct mood *m;
748 /** The size of the array */
749 unsigned size;
750 /** Pointer to the array of admissible files. */
751 struct admissible_file_info *array;
752 };
753
754 /**
755 * Add an entry to the array of admissible files.
756 *
757 * \param aft_row The audio file to be added.
758 * \param private_data Pointer to a struct admissible_file_info.
759 *
760 * \return Negative on errors, positive on success.
761 */
762 static int add_if_admissible(struct osl_row *aft_row, void *data)
763 {
764 struct admissible_array *aa = data;
765 int ret;
766 long score = 0;
767
768 ret = compute_mood_score(aft_row, aa->m, &score);
769 if (ret < 0)
770 return (ret == -E_NOT_ADMISSIBLE)? 1 : ret;
771 if (statistics.num >= aa->size) {
772 aa->size *= 2;
773 aa->size += 100;
774 aa->array = para_realloc(aa->array,
775 aa->size * sizeof(struct admissible_file_info));
776 }
777 aa->array[statistics.num].aft_row = aft_row;
778 aa->array[statistics.num].score = score;
779 ret = add_afs_statistics(aft_row);
780 if (ret < 0)
781 return ret;
782 return 1;
783 }
784
785 /**
786 * Compute the new quadratic deviation in case one element changes.
787 *
788 * \param n Number of elements.
789 * \param old_qd The quadratic deviation before the change.
790 * \param old_val The value that was replaced.
791 * \param new_val The replacement value.
792 * \param old_sum The sum of all elements before the update.
793 *
794 * \return The new quadratic deviation resulting from replacing old_val
795 * by new_val.
796 *
797 * Given n real numbers a_1, ..., a_n, their sum S = a_1 + ... + a_n,
798 * their quadratic deviation
799 *
800 * q = (a_1 - S/n)^2 + ... + (a_n - S/n)^2,
801 *
802 * and a real number b, the quadratic deviation q' of a_1,...a_{n-1}, b (ie.
803 * the last number a_n was replaced by b) may be computed in O(1) time in terms
804 * of n, q, a_n, b, and S as
805 *
806 * q' = q + d * s - (2 * S + d) * d / n,
807 *
808 * where d = b - a_n, and s = b + a_n.
809 *
810 * Example: n = 3, a_1 = 3, a_2 = 5, a_3 = 7, b = 10. Then S = 15, q = 8, d = 3,
811 * s = 17, so
812 *
813 * q + d * s - (2 * S + d) * d / n = 8 + 51 - 33 = 26,
814 *
815 * which equals q' = (3 - 6)^2 + (5 - 6)^2 + (10 - 6)^2.
816 *
817 */
818 _static_inline_ int64_t update_quadratic_deviation(int64_t n, int64_t old_qd,
819 int64_t old_val, int64_t new_val, int64_t old_sum)
820 {
821 int64_t delta = new_val - old_val;
822 int64_t sigma = new_val + old_val;
823 return old_qd + delta * sigma - (2 * old_sum + delta) * delta / n;
824 }
825
826 static int update_afs_statistics(struct afs_info *old_afsi, struct afs_info *new_afsi)
827 {
828 unsigned n;
829 int ret = get_num_admissible_files(&n);
830
831 if (ret < 0)
832 return ret;
833 assert(n);
834
835 statistics.last_played_qd = update_quadratic_deviation(n,
836 statistics.last_played_qd, old_afsi->last_played,
837 new_afsi->last_played, statistics.last_played_sum);
838 statistics.last_played_sum += new_afsi->last_played - old_afsi->last_played;
839
840 statistics.num_played_qd = update_quadratic_deviation(n,
841 statistics.num_played_qd, old_afsi->num_played,
842 new_afsi->num_played, statistics.num_played_sum);
843 statistics.num_played_sum += new_afsi->num_played - old_afsi->num_played;
844 return 1;
845 }
846
847 static int add_to_score_table(const struct osl_row *aft_row, long mood_score)
848 {
849 long score = (compute_dynamic_score(aft_row) + mood_score) / 3;
850 return score_add(aft_row, score);
851 }
852
853 static int delete_from_statistics_and_score_table(const struct osl_row *aft_row)
854 {
855 int ret = del_afs_statistics(aft_row);
856 if (ret < 0)
857 return ret;
858 return score_delete(aft_row);
859 }
860
861 /**
862 * Delete one entry from the statistics and from the score table.
863 *
864 * \param aft_row The audio file which is no longer admissible.
865 *
866 * \return Positive on success, negative on errors.
867 *
868 * \sa score_delete(), mood_update_audio_file().
869 */
870 int mood_delete_audio_file(const struct osl_row *aft_row)
871 {
872 int ret;
873
874 ret = row_belongs_to_score_table(aft_row);
875 if (ret < 0)
876 return ret;
877 if (!ret) /* not admissible, nothing to do */
878 return 1;
879 return delete_from_statistics_and_score_table(aft_row);
880 }
881
882 /**
883 * Compute the new score of an audio file wrt. the current mood.
884 *
885 * \param aft_row Determines the audio file.
886 * \param old_afsi The audio file selector info before updating.
887 *
888 * The \a old_afsi argument may be \p NULL which indicates that no changes to
889 * the audio file info were made.
890 *
891 * \return Positive on success, negative on errors.
892 */
893 int mood_update_audio_file(const struct osl_row *aft_row, struct afs_info *old_afsi)
894 {
895 long score, percent;
896 int ret, is_admissible, was_admissible = 0;
897 struct afs_info afsi;
898
899 if (!current_mood)
900 return 1; /* nothing to do */
901 ret = row_belongs_to_score_table(aft_row);
902 if (ret < 0)
903 return ret;
904 was_admissible = ret;
905 ret = compute_mood_score(aft_row, current_mood, &score);
906 is_admissible = (ret > 0);
907 if (!was_admissible && !is_admissible)
908 return 1;
909 if (was_admissible && !is_admissible)
910 return delete_from_statistics_and_score_table(aft_row);
911 if (!was_admissible && is_admissible) {
912 ret = add_afs_statistics(aft_row);
913 if (ret < 0)
914 return ret;
915 return add_to_score_table(aft_row, score);
916 }
917 /* update score */
918 ret = get_afsi_of_row(aft_row, &afsi);
919 if (ret < 0)
920 return ret;
921 if (old_afsi) {
922 ret = update_afs_statistics(old_afsi, &afsi);
923 if (ret < 0)
924 return ret;
925 }
926 score += compute_num_played_score(&afsi);
927 score += compute_last_played_score(&afsi);
928 score /= 3;
929 PARA_DEBUG_LOG("score: %li\n", score);
930 percent = (score + 100) / 3;
931 if (percent > 100)
932 percent = 100;
933 else if (percent < 0)
934 percent = 0;
935 PARA_DEBUG_LOG("re-inserting at %lu%%\n", percent);
936 return score_update(aft_row, percent);
937 }
938
939 static void log_statistics(void)
940 {
941 unsigned n = statistics.num;
942
943 if (!n) {
944 PARA_NOTICE_LOG("no admissible files\n");
945 return;
946 }
947 PARA_NOTICE_LOG("last_played mean: %lli, last_played sigma: %llu\n",
948 (long long int)(statistics.last_played_sum / n),
949 (long long unsigned)int_sqrt(statistics.last_played_qd / n));
950 PARA_NOTICE_LOG("num_played mean: %lli, num_played sigma: %llu\n",
951 (long long int)statistics.num_played_sum / n,
952 (long long unsigned)int_sqrt(statistics.num_played_qd / n));
953 }
954
955 /**
956 * Change the current mood.
957 *
958 * \param mood_name The name of the mood to open.
959 *
960 * There are two special cases: If \a mood_name is \a NULL, load the
961 * first available mood. If \a mood_name is the empty string "", load
962 * the dummy mood that accepts every audio file and uses a scoring method
963 * based only on the \a last_played information.
964 *
965 * If there is already an open mood, it will be closed first.
966 *
967 * \return Positive on success, negative on errors. Loading the dummy mood
968 * always succeeds.
969 *
970 * \sa struct admissible_file_info, struct admissible_array, struct
971 * afs_info::last_played, mood_close().
972 */
973 int change_current_mood(char *mood_name)
974 {
975 int i, ret;
976 struct admissible_array aa = {
977 .size = 0,
978 .array = NULL
979 };
980
981 if (!mood_name) {
982 struct mood *m;
983 ret = load_first_available_mood(&m);
984 if (ret < 0)
985 return ret;
986 destroy_mood(current_mood);
987 current_mood = m;
988 } else if (*mood_name) {
989 struct mood *m;
990 struct osl_row *row;
991 struct osl_object obj = {
992 .data = mood_name,
993 .size = strlen(mood_name) + 1
994 };
995 ret = osl_get_row(moods_table, BLOBCOL_NAME, &obj, &row);
996 if (ret < 0) {
997 PARA_NOTICE_LOG("no such mood: %s\n", mood_name);
998 return ret;
999 }
1000 ret = load_mood(row, &m);
1001 if (ret < 0)
1002 return ret;
1003 destroy_mood(current_mood);
1004 current_mood = m;
1005 } else {
1006 destroy_mood(current_mood);
1007 current_mood = alloc_new_mood("dummy");
1008 }
1009 aa.m = current_mood;
1010 PARA_NOTICE_LOG("loaded mood %s\n", current_mood->name);
1011 PARA_INFO_LOG("%s\n", "computing statistics of admissible files");
1012 ret = audio_file_loop(&aa, add_if_admissible);
1013 if (ret < 0)
1014 return ret;
1015 log_statistics();
1016 PARA_NOTICE_LOG("%d admissible files \n", statistics.num);
1017 for (i = 0; i < statistics.num; i++) {
1018 struct admissible_file_info *a = aa.array + i;
1019 ret = add_to_score_table(a->aft_row, a->score);
1020 if (ret < 0)
1021 goto out;
1022 }
1023 PARA_NOTICE_LOG("score add complete\n");
1024 ret = 1;
1025 out:
1026 free(aa.array);
1027 return ret;
1028 }
1029
1030 /**
1031 * Close the current mood.
1032 *
1033 * Free all resources of the current mood which were allocated during
1034 * mood_open().
1035 */
1036 void close_current_mood(void)
1037 {
1038 destroy_mood(current_mood);
1039 current_mood = NULL;
1040 memset(&statistics, 0, sizeof(statistics));
1041 }
1042
1043 /**
1044 * Close and re-open the current mood.
1045 *
1046 * This function is used if changes to the audio file table or the
1047 * attribute table were made that render the current list of admissible
1048 * files useless. For example, if an attribute is removed from the
1049 * attribute table, this function is called.
1050 *
1051 * \return Positive on success, negative on errors. If no mood is currently
1052 * open, the function returns success.
1053 *
1054 * \sa mood_open(), mood_close().
1055 */
1056 int reload_current_mood(void)
1057 {
1058 int ret;
1059 char *mood_name;
1060
1061 if (!current_mood)
1062 return 1;
1063 score_shutdown(0);
1064 mood_name = para_strdup(current_mood->name);
1065 close_current_mood();
1066 ret = change_current_mood(mood_name);
1067 free(mood_name);
1068 return ret;
1069 }