mood.c: Introduce DEFINE_MOOD_METHOD and DEFINE_MOOD_METHOD_WITH_CLEANUP.
[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 #define DEFINE_MOOD_METHOD(_name) \
314 .parser = mm_ ## _name ## _parser, \
315 .score_function = mm_ ## _name ## _score_function, \
316 .name = #_name
317
318 #define DEFINE_MOOD_METHOD_WITH_CLEANUP(_name) \
319 DEFINE_MOOD_METHOD(_name), \
320 .cleanup = mm_ ## _name ## _cleanup
321
322 static const struct mood_method mood_methods[] = {
323 {DEFINE_MOOD_METHOD(no_attributes_set)},
324 {DEFINE_MOOD_METHOD(played_rarely)},
325 {DEFINE_MOOD_METHOD(is_set)},
326 {DEFINE_MOOD_METHOD_WITH_CLEANUP(name_like)},
327 {.parser = NULL}
328 };
329
330 static void cleanup_list_entry(struct mood_item *item)
331 {
332 if (item->method && item->method->cleanup)
333 item->method->cleanup(item->parser_data);
334 else
335 free(item->parser_data);
336 list_del(&item->mood_item_node);
337 free(item);
338 }
339
340 static void destroy_mood(struct mood *m)
341 {
342 struct mood_item *tmp, *item;
343
344 if (!m)
345 return;
346 list_for_each_entry_safe(item, tmp, &m->accept_list, mood_item_node)
347 cleanup_list_entry(item);
348 list_for_each_entry_safe(item, tmp, &m->deny_list, mood_item_node)
349 cleanup_list_entry(item);
350 list_for_each_entry_safe(item, tmp, &m->score_list, mood_item_node)
351 cleanup_list_entry(item);
352 free(m->name);
353 free(m);
354 }
355
356 static struct mood *alloc_new_mood(const char *name)
357 {
358 struct mood *m = para_calloc(sizeof(struct mood));
359 m->name = para_strdup(name);
360 INIT_LIST_HEAD(&m->accept_list);
361 INIT_LIST_HEAD(&m->deny_list);
362 INIT_LIST_HEAD(&m->score_list);
363 return m;
364 }
365
366 /** The different types of a mood line. */
367 enum mood_line_type {
368 /** Invalid. */
369 ML_INVALID,
370 /** Accept line. */
371 ML_ACCEPT,
372 /** Deny line. */
373 ML_DENY,
374 /** Score line. */
375 ML_SCORE
376 };
377
378 struct mood_line_parser_data {
379 struct mood *m;
380 unsigned line_num;
381 };
382
383 /*
384 * <accept [with score <score>] | deny [with score <score>] | score <score>>
385 * [if] [not] <mood_method> [options]
386 * <score> is either an integer or "random" which assigns a random score to
387 * all matching files
388 */
389
390 static int parse_mood_line(char *mood_line, void *data)
391 {
392 struct mood_line_parser_data *mlpd = data;
393 char **argv;
394 char *delim = " \t";
395 unsigned num_words;
396 char **w;
397 int i, ret;
398 enum mood_line_type mlt = ML_INVALID;
399 struct mood_item *mi = NULL;
400 char *buf = para_strdup(mood_line);
401
402 mlpd->line_num++;
403 num_words = split_args(buf, &argv, delim);
404 ret = 1;
405 if (!num_words) /* empty line */
406 goto out;
407 w = argv;
408 if (**w == '#') /* comment */
409 goto out;
410 if (!strcmp(*w, "accept"))
411 mlt = ML_ACCEPT;
412 else if (!strcmp(*w, "deny"))
413 mlt = ML_DENY;
414 else if (!strcmp(*w, "score"))
415 mlt = ML_SCORE;
416 ret = -E_MOOD_SYNTAX;
417 if (mlt == ML_INVALID)
418 goto out;
419 mi = para_calloc(sizeof(struct mood_item));
420 if (mlt != ML_SCORE) {
421 ret = -E_MOOD_SYNTAX;
422 w++;
423 if (!*w)
424 goto out;
425 if (!strcmp(*w, "with")) {
426 w++;
427 if (!*w)
428 goto out;
429 }
430 }
431 if (mlt == ML_SCORE || !strcmp(*w, "score")) {
432 ret = -E_MOOD_SYNTAX;
433 w++;
434 if (!*w)
435 goto out;
436 if (strcmp(*w, "random")) {
437 mi->random_score = 0;
438 ret = para_atoi32(*w, &mi->score_arg);
439 if (ret < 0)
440 goto out;
441 } else {
442 mi->random_score = 1;
443 if (!*(w + 1))
444 goto success; /* the line "score random" is valid */
445 }
446 } else
447 mi->score_arg = 0;
448 ret = -E_MOOD_SYNTAX;
449 w++;
450 if (!*w)
451 goto out;
452 if (!strcmp(*w, "if")) {
453 ret = -E_MOOD_SYNTAX;
454 w++;
455 if (!*w)
456 goto out;
457 }
458 if (!strcmp(*w, "not")) {
459 ret = -E_MOOD_SYNTAX;
460 w++;
461 if (!*w)
462 goto out;
463 mi->logical_not = 1;
464 } else
465 mi->logical_not = 0;
466 for (i = 0; mood_methods[i].parser; i++) {
467 if (strcmp(*w, mood_methods[i].name))
468 continue;
469 break;
470 }
471 ret = -E_MOOD_SYNTAX;
472 if (!mood_methods[i].parser)
473 goto out;
474 w++;
475 ret = mood_methods[i].parser(*w, &mi->parser_data);
476 if (ret < 0)
477 goto out;
478 mi->method = &mood_methods[i];
479 success:
480 if (mlpd->m) {
481 if (mlt == ML_ACCEPT)
482 para_list_add(&mi->mood_item_node, &mlpd->m->accept_list);
483 else if (mlt == ML_DENY)
484 para_list_add(&mi->mood_item_node, &mlpd->m->deny_list);
485 else
486 para_list_add(&mi->mood_item_node, &mlpd->m->score_list);
487 }
488 PARA_DEBUG_LOG("%s entry added, method: %p\n", mlt == ML_ACCEPT? "accept" :
489 (mlt == ML_DENY? "deny" : "score"), mi->method);
490 ret = 1;
491 out:
492 free(argv);
493 free(buf);
494 if (ret >= 0)
495 return ret;
496 if (mi) {
497 free(mi->parser_data);
498 free(mi);
499 }
500 return ret;
501 }
502
503 static int load_mood(const struct osl_row *mood_row, struct mood **m)
504 {
505 char *mood_name;
506 struct osl_object mood_def;
507 struct mood_line_parser_data mlpd = {.line_num = 0};
508 int ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
509
510 if (ret < 0)
511 return ret;
512 if (!*mood_name)
513 return -E_DUMMY_ROW;
514 mlpd.m = alloc_new_mood(mood_name);
515 ret = for_each_line_ro(mood_def.data, mood_def.size,
516 parse_mood_line, &mlpd);
517 osl_close_disk_object(&mood_def);
518 if (ret < 0) {
519 PARA_ERROR_LOG("unable to load mood %s: %s\n", mlpd.m->name,
520 PARA_STRERROR(-ret));
521 destroy_mood(mlpd.m);
522 return ret;
523 }
524 PARA_INFO_LOG("loaded mood %s\n", mlpd.m->name);
525 *m = mlpd.m;
526 return 1;
527 }
528
529 /*
530 * Calls load_mood() and reverts its error value: It returns -E_MOOD_LOADED
531 * on _success_, and 1 on errors. This way the loop over all moods stops at the
532 * first valid mood.
533 */
534 static int load_mood_loop_func(struct osl_row *mood_row, void *data)
535 {
536 struct mood **m = data;
537 int ret = load_mood(mood_row, m);
538 if (ret < 0) {
539 if (ret != -E_DUMMY_ROW)
540 PARA_NOTICE_LOG("invalid mood (%d), trying next mood\n", ret);
541 return 1;
542 }
543 return -E_MOOD_LOADED;
544 }
545
546 static int load_first_available_mood(struct mood **m)
547 {
548 int ret = osl_rbtree_loop(moods_table, BLOBCOL_NAME, m,
549 load_mood_loop_func);
550 if (ret == -E_MOOD_LOADED) /* success */
551 return 1;
552 if (ret < 0)
553 return ret; /* error */
554 PARA_NOTICE_LOG("no valid mood found\n");
555 return -E_NO_MOOD;
556 }
557
558 static int check_mood(struct osl_row *mood_row, void *data)
559 {
560 struct para_buffer *pb = data;
561 char *mood_name;
562 struct osl_object mood_def;
563 struct mood_line_parser_data mlpd = {.line_num = 0};
564
565 int ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
566
567 if (ret < 0) {
568 para_printf(pb, "failed to get mood definition\n");
569 return ret;
570 }
571 if (!*mood_name) /* ignore dummy row */
572 goto out;
573 para_printf(pb, "checking mood %s...\n", mood_name);
574 ret = for_each_line_ro(mood_def.data, mood_def.size,
575 parse_mood_line, &mlpd);
576 if (ret < 0)
577 para_printf(pb, "%s line %u: %s\n", mood_name, mlpd.line_num,
578 PARA_STRERROR(-ret));
579 out:
580 osl_close_disk_object(&mood_def);
581 return 1;
582 }
583
584 /**
585 * Check all moods for syntax errors.
586 *
587 * \param query Unused.
588 * \param result: Contains check messages.
589 */
590 int mood_check_callback(__a_unused const struct osl_object *query,
591 struct osl_object *result)
592 {
593 struct para_buffer pb = {.buf = NULL};
594
595 para_printf(&pb, "checking moods...\n");
596 osl_rbtree_loop(moods_table, BLOBCOL_ID, &pb,
597 check_mood);
598 result->data = pb.buf;
599 result->size = pb.size;
600 return 1;
601 }
602
603 #if 0
604 static unsigned int_log2(uint64_t x)
605 {
606 unsigned res = 0;
607
608 while (x) {
609 x /= 2;
610 res++;
611 }
612 return res;
613 }
614 #endif
615
616 static int64_t normalized_value(int64_t x, int64_t n, int64_t sum, int64_t qd)
617 {
618 if (!n || !qd)
619 return 0;
620 return 100 * (n * x - sum) / (int64_t)int_sqrt(n * qd);
621 }
622
623 static long compute_num_played_score(struct afs_info *afsi)
624 {
625 return -normalized_value(afsi->num_played, statistics.num,
626 statistics.num_played_sum, statistics.num_played_qd);
627 }
628
629 static long compute_last_played_score(struct afs_info *afsi)
630 {
631 return -normalized_value(afsi->last_played, statistics.num,
632 statistics.last_played_sum, statistics.last_played_qd);
633 }
634
635 static long compute_dynamic_score(const struct osl_row *aft_row)
636 {
637 struct afs_info afsi;
638 int64_t score, nscore = 0, lscore = 0;
639 int ret;
640
641 ret = get_afsi_of_row(aft_row, &afsi);
642 if (ret < 0)
643 return -100;
644 nscore = compute_num_played_score(&afsi);
645 lscore = compute_last_played_score(&afsi);
646 score = nscore + lscore;
647 return score;
648 }
649
650 static int add_afs_statistics(const struct osl_row *row)
651 {
652 uint64_t n, x, s;
653 struct afs_info afsi;
654 int ret;
655
656 ret = get_afsi_of_row(row, &afsi);
657 if (ret < 0)
658 return ret;
659 n = statistics.num;
660 x = afsi.last_played;
661 s = statistics.last_played_sum;
662 if (n > 0)
663 statistics.last_played_qd += (x - s / n) * (x - s / n) * n / (n + 1);
664 statistics.last_played_sum += x;
665
666 x = afsi.num_played;
667 s = statistics.num_played_sum;
668 if (n > 0)
669 statistics.num_played_qd += (x - s / n) * (x - s / n) * n / (n + 1);
670 statistics.num_played_sum += x;
671 statistics.num++;
672 return 1;
673 }
674
675 static int del_afs_statistics(const struct osl_row *row)
676 {
677 uint64_t n, s, q, a, new_s;
678 struct afs_info afsi;
679 int ret;
680 ret = get_afsi_of_row(row, &afsi);
681 if (ret < 0)
682 return ret;
683 n = statistics.num;
684 assert(n);
685 if (n == 1) {
686 memset(&statistics, 0, sizeof(statistics));
687 return 1;
688 }
689
690 s = statistics.last_played_sum;
691 q = statistics.last_played_qd;
692 a = afsi.last_played;
693 new_s = s - a;
694 statistics.last_played_sum = new_s;
695 statistics.last_played_qd = q + s * s / n - a * a
696 - new_s * new_s / (n - 1);
697
698 s = statistics.num_played_sum;
699 q = statistics.num_played_qd;
700 a = afsi.num_played;
701 new_s = s - a;
702 statistics.num_played_sum = new_s;
703 statistics.num_played_qd = q + s * s / n - a * a
704 - new_s * new_s / (n - 1);
705
706 statistics.num--;
707 return 1;
708 }
709
710 /**
711 * Structure used during mood_open().
712 *
713 * At mood open time, we look at each file in the audio file table in order to
714 * determine whether it is admissible. If a file happens to be admissible, its
715 * mood score is computed by calling each relevant mood_score_function. Next,
716 * we update the afs_statistics and add a struct admissible_file_info to a
717 * temporary array.
718 *
719 * If all files have been processed that way, the final score of each
720 * admissible file is computed by adding the dynamic score (which depends on
721 * the afs_statistics) to the mood score. Finally, all audio files in the
722 * array are added to the score table and the admissible array is freed.
723 *
724 * \sa mood_method, admissible_array.
725 */
726 struct admissible_file_info
727 {
728 /** The admissible audio file. */
729 struct osl_row *aft_row;
730 /** Its score. */
731 long score;
732 };
733
734 /** The temporary array of admissible files. */
735 struct admissible_array {
736 /** Files are admissible wrt. this mood. */
737 struct mood *m;
738 /** The size of the array */
739 unsigned size;
740 /** Pointer to the array of admissible files. */
741 struct admissible_file_info *array;
742 };
743
744 /**
745 * Add an entry to the array of admissible files.
746 *
747 * \param aft_row The audio file to be added.
748 * \param private_data Pointer to a struct admissible_file_info.
749 *
750 * \return Negative on errors, positive on success.
751 */
752 static int add_if_admissible(struct osl_row *aft_row, void *data)
753 {
754 struct admissible_array *aa = data;
755 int ret;
756 long score = 0;
757
758 ret = compute_mood_score(aft_row, aa->m, &score);
759 if (ret < 0)
760 return (ret == -E_NOT_ADMISSIBLE)? 1 : ret;
761 if (statistics.num >= aa->size) {
762 aa->size *= 2;
763 aa->size += 100;
764 aa->array = para_realloc(aa->array,
765 aa->size * sizeof(struct admissible_file_info));
766 }
767 aa->array[statistics.num].aft_row = aft_row;
768 aa->array[statistics.num].score = score;
769 ret = add_afs_statistics(aft_row);
770 if (ret < 0)
771 return ret;
772 return 1;
773 }
774
775 /**
776 * Compute the new quadratic deviation in case one element changes.
777 *
778 * \param n Number of elements.
779 * \param old_qd The quadratic deviation before the change.
780 * \param old_val The value that was replaced.
781 * \param new_val The replacement value.
782 * \param old_sum The sum of all elements before the update.
783 *
784 * \return The new quadratic deviation resulting from replacing old_val
785 * by new_val.
786 *
787 * Given n real numbers a_1, ..., a_n, their sum S = a_1 + ... + a_n,
788 * their quadratic deviation
789 *
790 * q = (a_1 - S/n)^2 + ... + (a_n - S/n)^2,
791 *
792 * and a real number b, the quadratic deviation q' of a_1,...a_{n-1}, b (ie.
793 * the last number a_n was replaced by b) may be computed in O(1) time in terms
794 * of n, q, a_n, b, and S as
795 *
796 * q' = q + d * s - (2 * S + d) * d / n,
797 *
798 * where d = b - a_n, and s = b + a_n.
799 *
800 * Example: n = 3, a_1 = 3, a_2 = 5, a_3 = 7, b = 10. Then S = 15, q = 8, d = 3,
801 * s = 17, so
802 *
803 * q + d * s - (2 * S + d) * d / n = 8 + 51 - 33 = 26,
804 *
805 * which equals q' = (3 - 6)^2 + (5 - 6)^2 + (10 - 6)^2.
806 *
807 */
808 _static_inline_ int64_t update_quadratic_deviation(int64_t n, int64_t old_qd,
809 int64_t old_val, int64_t new_val, int64_t old_sum)
810 {
811 int64_t delta = new_val - old_val;
812 int64_t sigma = new_val + old_val;
813 return old_qd + delta * sigma - (2 * old_sum + delta) * delta / n;
814 }
815
816 static int update_afs_statistics(struct afs_info *old_afsi, struct afs_info *new_afsi)
817 {
818 unsigned n;
819 int ret = get_num_admissible_files(&n);
820
821 if (ret < 0)
822 return ret;
823 assert(n);
824
825 statistics.last_played_qd = update_quadratic_deviation(n,
826 statistics.last_played_qd, old_afsi->last_played,
827 new_afsi->last_played, statistics.last_played_sum);
828 statistics.last_played_sum += new_afsi->last_played - old_afsi->last_played;
829
830 statistics.num_played_qd = update_quadratic_deviation(n,
831 statistics.num_played_qd, old_afsi->num_played,
832 new_afsi->num_played, statistics.num_played_sum);
833 statistics.num_played_sum += new_afsi->num_played - old_afsi->num_played;
834 return 1;
835 }
836
837 static int add_to_score_table(const struct osl_row *aft_row, long mood_score)
838 {
839 long score = (compute_dynamic_score(aft_row) + mood_score) / 3;
840 return score_add(aft_row, score);
841 }
842
843 static int delete_from_statistics_and_score_table(const struct osl_row *aft_row)
844 {
845 int ret = del_afs_statistics(aft_row);
846 if (ret < 0)
847 return ret;
848 return score_delete(aft_row);
849 }
850
851 /**
852 * Delete one entry from the statistics and from the score table.
853 *
854 * \param aft_row The audio file which is no longer admissible.
855 *
856 * \return Positive on success, negative on errors.
857 *
858 * \sa score_delete(), mood_update_audio_file().
859 */
860 int mood_delete_audio_file(const struct osl_row *aft_row)
861 {
862 int ret;
863
864 ret = row_belongs_to_score_table(aft_row);
865 if (ret < 0)
866 return ret;
867 if (!ret) /* not admissible, nothing to do */
868 return 1;
869 return delete_from_statistics_and_score_table(aft_row);
870 }
871
872 /**
873 * Compute the new score of an audio file wrt. the current mood.
874 *
875 * \param aft_row Determines the audio file.
876 * \param old_afsi The audio file selector info before updating.
877 *
878 * The \a old_afsi argument may be \p NULL which indicates that no changes to
879 * the audio file info were made.
880 *
881 * \return Positive on success, negative on errors.
882 */
883 int mood_update_audio_file(const struct osl_row *aft_row, struct afs_info *old_afsi)
884 {
885 long score, percent;
886 int ret, is_admissible, was_admissible = 0;
887 struct afs_info afsi;
888
889 if (!current_mood)
890 return 1; /* nothing to do */
891 ret = row_belongs_to_score_table(aft_row);
892 if (ret < 0)
893 return ret;
894 was_admissible = ret;
895 ret = compute_mood_score(aft_row, current_mood, &score);
896 is_admissible = (ret > 0);
897 if (!was_admissible && !is_admissible)
898 return 1;
899 if (was_admissible && !is_admissible)
900 return delete_from_statistics_and_score_table(aft_row);
901 if (!was_admissible && is_admissible) {
902 ret = add_afs_statistics(aft_row);
903 if (ret < 0)
904 return ret;
905 return add_to_score_table(aft_row, score);
906 }
907 /* update score */
908 ret = get_afsi_of_row(aft_row, &afsi);
909 if (ret < 0)
910 return ret;
911 if (old_afsi) {
912 ret = update_afs_statistics(old_afsi, &afsi);
913 if (ret < 0)
914 return ret;
915 }
916 score += compute_num_played_score(&afsi);
917 score += compute_last_played_score(&afsi);
918 score /= 3;
919 PARA_DEBUG_LOG("score: %li\n", score);
920 percent = (score + 100) / 3;
921 if (percent > 100)
922 percent = 100;
923 else if (percent < 0)
924 percent = 0;
925 PARA_DEBUG_LOG("re-inserting at %lu%%\n", percent);
926 return score_update(aft_row, percent);
927 }
928
929 static void log_statistics(void)
930 {
931 unsigned n = statistics.num;
932
933 if (!n) {
934 PARA_NOTICE_LOG("no admissible files\n");
935 return;
936 }
937 PARA_NOTICE_LOG("last_played mean: %lli, last_played sigma: %llu\n",
938 (long long int)(statistics.last_played_sum / n),
939 (long long unsigned)int_sqrt(statistics.last_played_qd / n));
940 PARA_NOTICE_LOG("num_played mean: %lli, num_played sigma: %llu\n",
941 (long long int)statistics.num_played_sum / n,
942 (long long unsigned)int_sqrt(statistics.num_played_qd / n));
943 }
944
945 /**
946 * Change the current mood.
947 *
948 * \param mood_name The name of the mood to open.
949 *
950 * There are two special cases: If \a mood_name is \a NULL, load the
951 * first available mood. If \a mood_name is the empty string "", load
952 * the dummy mood that accepts every audio file and uses a scoring method
953 * based only on the \a last_played information.
954 *
955 * If there is already an open mood, it will be closed first.
956 *
957 * \return Positive on success, negative on errors. Loading the dummy mood
958 * always succeeds.
959 *
960 * \sa struct admissible_file_info, struct admissible_array, struct
961 * afs_info::last_played, mood_close().
962 */
963 int change_current_mood(char *mood_name)
964 {
965 int i, ret;
966 struct admissible_array aa = {
967 .size = 0,
968 .array = NULL
969 };
970
971 if (!mood_name) {
972 struct mood *m;
973 ret = load_first_available_mood(&m);
974 if (ret < 0)
975 return ret;
976 destroy_mood(current_mood);
977 current_mood = m;
978 } else if (*mood_name) {
979 struct mood *m;
980 struct osl_row *row;
981 struct osl_object obj = {
982 .data = mood_name,
983 .size = strlen(mood_name) + 1
984 };
985 ret = osl_get_row(moods_table, BLOBCOL_NAME, &obj, &row);
986 if (ret < 0) {
987 PARA_NOTICE_LOG("no such mood: %s\n", mood_name);
988 return ret;
989 }
990 ret = load_mood(row, &m);
991 if (ret < 0)
992 return ret;
993 destroy_mood(current_mood);
994 current_mood = m;
995 } else {
996 destroy_mood(current_mood);
997 current_mood = alloc_new_mood("dummy");
998 }
999 aa.m = current_mood;
1000 PARA_NOTICE_LOG("loaded mood %s\n", current_mood->name);
1001 PARA_INFO_LOG("%s\n", "computing statistics of admissible files");
1002 ret = audio_file_loop(&aa, add_if_admissible);
1003 if (ret < 0)
1004 return ret;
1005 log_statistics();
1006 PARA_NOTICE_LOG("%d admissible files \n", statistics.num);
1007 for (i = 0; i < statistics.num; i++) {
1008 struct admissible_file_info *a = aa.array + i;
1009 ret = add_to_score_table(a->aft_row, a->score);
1010 if (ret < 0)
1011 goto out;
1012 }
1013 PARA_NOTICE_LOG("score add complete\n");
1014 ret = 1;
1015 out:
1016 free(aa.array);
1017 return ret;
1018 }
1019
1020 /**
1021 * Close the current mood.
1022 *
1023 * Free all resources of the current mood which were allocated during
1024 * mood_open().
1025 */
1026 void close_current_mood(void)
1027 {
1028 destroy_mood(current_mood);
1029 current_mood = NULL;
1030 memset(&statistics, 0, sizeof(statistics));
1031 }
1032
1033 /**
1034 * Close and re-open the current mood.
1035 *
1036 * This function is used if changes to the audio file table or the
1037 * attribute table were made that render the current list of admissible
1038 * files useless. For example, if an attribute is removed from the
1039 * attribute table, this function is called.
1040 *
1041 * \return Positive on success, negative on errors. If no mood is currently
1042 * open, the function returns success.
1043 *
1044 * \sa mood_open(), mood_close().
1045 */
1046 int reload_current_mood(void)
1047 {
1048 int ret;
1049 char *mood_name;
1050
1051 if (!current_mood)
1052 return 1;
1053 score_shutdown(0);
1054 mood_name = para_strdup(current_mood->name);
1055 close_current_mood();
1056 ret = change_current_mood(mood_name);
1057 free(mood_name);
1058 return ret;
1059 }