e905f92cc64b4e99d55691d3d9e5805e3f3985d1
[paraslash.git] / mood.c
1 /*
2 * Copyright (C) 2007-2012 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 <regex.h>
10 #include <osl.h>
11
12 #include "para.h"
13 #include "error.h"
14 #include "string.h"
15 #include "afh.h"
16 #include "afs.h"
17 #include "list.h"
18 #include "ipc.h"
19 #include "mm.h"
20 #include "sideband.h"
21
22 /**
23 * Contains statistical data of the currently admissible audio files.
24 *
25 * It is used to assign normalized score values to each admissible audio file.
26 */
27 struct afs_statistics {
28 /** Sum of num played over all admissible files. */
29 int64_t num_played_sum;
30 /** Sum of last played times over all admissible files. */
31 int64_t last_played_sum;
32 /** Quadratic deviation of num played time. */
33 int64_t num_played_qd;
34 /** Quadratic deviation of last played time. */
35 int64_t last_played_qd;
36 /** Number of admissible files */
37 unsigned num;
38 };
39 static struct afs_statistics statistics;
40
41 /**
42 * Each line of the current mood corresponds to a mood_item.
43 */
44 struct mood_item {
45 /** The method this line is referring to. */
46 const struct mood_method *method;
47 /** The data structure computed by the mood parser. */
48 void *parser_data;
49 /** The given score value, or zero if none was given. */
50 int32_t score_arg;
51 /** Non-zero if random scoring was requested. */
52 int random_score;
53 /** Whether the "not" keyword was given in the mood line. */
54 int logical_not;
55 /** The position in the list of items. */
56 struct list_head mood_item_node;
57 };
58
59 /**
60 * Created from the mood definition by mood_open().
61 *
62 * When a mood is opened, each line of its definition is investigated, and a
63 * corresponding mood item is produced. Each mood line starts with \p accept,
64 * \p deny, or \p score which determines the type of the mood line. For each
65 * such type a linked list is maintained whose entries are the mood items.
66 *
67 * \sa mood_item, mood_open().
68 */
69 struct mood {
70 /** The name of this mood. */
71 char *name;
72 /** The list of mood items of type \p accept. */
73 struct list_head accept_list;
74 /** The list of mood items of type \p deny. */
75 struct list_head deny_list;
76 /** The list of mood items of type \p score. */
77 struct list_head score_list;
78 };
79
80 static struct mood *current_mood;
81
82 /**
83 * Rough approximation to sqrt.
84 *
85 * \param x Integer of which to calculate the sqrt.
86 *
87 * \return An integer res with res * res <= x.
88 */
89 __a_const static uint64_t int_sqrt(uint64_t x)
90 {
91 uint64_t op, res, one = 1;
92 op = x;
93 res = 0;
94
95 one = one << 62;
96 while (one > op)
97 one >>= 2;
98
99 while (one != 0) {
100 if (op >= res + one) {
101 op = op - (res + one);
102 res = res + 2 * one;
103 }
104 res /= 2;
105 one /= 4;
106 }
107 // PARA_NOTICE_LOG("sqrt(%llu) = %llu\n", x, res);
108 return res;
109 }
110
111 /*
112 * Returns true if row matches, false if it does not match. In any case score
113 * and score_arg_sum are set/increased accordingly.
114 */
115 static bool get_item_score(struct mood_item *item, const struct afs_info *afsi,
116 const struct afh_info *afhi, const char *path, long *score,
117 long *score_arg_sum)
118 {
119 int ret;
120 bool match = true;
121
122 *score_arg_sum += item->random_score? 100 : PARA_ABS(item->score_arg);
123 ret = 100;
124 if (item->method) {
125 ret = item->method->score_function(path, afsi, afhi,
126 item->parser_data);
127 if ((ret < 0 && !item->logical_not) || (ret >= 0 && item->logical_not))
128 match = false;
129 }
130 if (item->random_score)
131 *score = PARA_ABS(ret) * para_random(100);
132 else
133 *score = PARA_ABS(ret) * item->score_arg;
134 return match;
135 }
136
137 /* returns 1 if row admissible, 0 if not, negative on errors */
138 static int compute_mood_score(const struct osl_row *aft_row, struct mood *m,
139 long *result)
140 {
141 struct mood_item *item;
142 int ret;
143 bool match;
144 long score_arg_sum = 0, score = 0, item_score;
145 struct afs_info afsi;
146 struct afh_info afhi;
147 char *path;
148
149 if (!m)
150 return -E_NO_MOOD;
151 ret = get_afsi_of_row(aft_row, &afsi);
152 if (ret< 0)
153 return ret;
154 ret = get_afhi_of_row(aft_row, &afhi);
155 if (ret< 0)
156 return ret;
157 ret = get_audio_file_path_of_row(aft_row, &path);
158 if (ret< 0)
159 return ret;
160 /* reject audio file if it matches any entry in the deny list */
161 list_for_each_entry(item, &m->deny_list, mood_item_node) {
162 match = get_item_score(item, &afsi, &afhi, path, &item_score,
163 &score_arg_sum);
164 if (match) /* not admissible */
165 return 0;
166 score += item_score;
167 }
168 match = false;
169 list_for_each_entry(item, &m->accept_list, mood_item_node) {
170 ret = get_item_score(item, &afsi, &afhi, path, &item_score,
171 &score_arg_sum);
172 if (ret == 0)
173 continue;
174 match = true;
175 score += item_score;
176 }
177 /* reject if there is no matching entry in the accept list */
178 if (!match && !list_empty(&m->accept_list))
179 return 0;
180 list_for_each_entry(item, &m->score_list, mood_item_node) {
181 match = get_item_score(item, &afsi, &afhi, path, &item_score,
182 &score_arg_sum);
183 if (match)
184 score += item_score;
185 }
186 if (score_arg_sum)
187 score /= score_arg_sum;
188 *result = score;
189 return 1;
190 }
191
192 static void cleanup_list_entry(struct mood_item *item)
193 {
194 if (item->method && item->method->cleanup)
195 item->method->cleanup(item->parser_data);
196 else
197 free(item->parser_data);
198 list_del(&item->mood_item_node);
199 free(item);
200 }
201
202 static void destroy_mood(struct mood *m)
203 {
204 struct mood_item *tmp, *item;
205
206 if (!m)
207 return;
208 list_for_each_entry_safe(item, tmp, &m->accept_list, mood_item_node)
209 cleanup_list_entry(item);
210 list_for_each_entry_safe(item, tmp, &m->deny_list, mood_item_node)
211 cleanup_list_entry(item);
212 list_for_each_entry_safe(item, tmp, &m->score_list, mood_item_node)
213 cleanup_list_entry(item);
214 free(m->name);
215 free(m);
216 }
217
218 static struct mood *alloc_new_mood(const char *name)
219 {
220 struct mood *m = para_calloc(sizeof(struct mood));
221 m->name = para_strdup(name);
222 INIT_LIST_HEAD(&m->accept_list);
223 INIT_LIST_HEAD(&m->deny_list);
224 INIT_LIST_HEAD(&m->score_list);
225 return m;
226 }
227
228 /** The different types of a mood line. */
229 enum mood_line_type {
230 /** Invalid. */
231 ML_INVALID,
232 /** Accept line. */
233 ML_ACCEPT,
234 /** Deny line. */
235 ML_DENY,
236 /** Score line. */
237 ML_SCORE
238 };
239
240 /** Data passed to the parser of a mood line. */
241 struct mood_line_parser_data {
242 /** The mood this mood line belongs to. */
243 struct mood *m;
244 /** The line number in the mood definition. */
245 unsigned line_num;
246 };
247
248 /*
249 * <accept [with score <score>] | deny [with score <score>] | score <score>>
250 * [if] [not] <mood_method> [options]
251 * <score> is either an integer or "random" which assigns a random score to
252 * all matching files
253 */
254
255 static int parse_mood_line(char *mood_line, void *data)
256 {
257 struct mood_line_parser_data *mlpd = data;
258 char **argv;
259 unsigned num_words;
260 char **w;
261 int i, ret;
262 enum mood_line_type mlt = ML_INVALID;
263 struct mood_item *mi = NULL;
264
265 mlpd->line_num++;
266 ret = create_argv(mood_line, " \t", &argv);
267 if (ret < 0)
268 return ret;
269 num_words = ret;
270 if (!num_words) /* empty line */
271 goto out;
272 w = argv;
273 if (**w == '#') /* comment */
274 goto out;
275 if (!strcmp(*w, "accept"))
276 mlt = ML_ACCEPT;
277 else if (!strcmp(*w, "deny"))
278 mlt = ML_DENY;
279 else if (!strcmp(*w, "score"))
280 mlt = ML_SCORE;
281 ret = -E_MOOD_SYNTAX;
282 if (mlt == ML_INVALID)
283 goto out;
284 mi = para_calloc(sizeof(struct mood_item));
285 if (mlt != ML_SCORE) {
286 ret = -E_MOOD_SYNTAX;
287 w++;
288 if (!*w)
289 goto out;
290 if (strcmp(*w, "with"))
291 goto check_for_if;
292 w++;
293 if (!*w)
294 goto out;
295 if (strcmp(*w, "score"))
296 goto out;
297 }
298 if (mlt == ML_SCORE || !strcmp(*w, "score")) {
299 ret = -E_MOOD_SYNTAX;
300 w++;
301 if (!*w)
302 goto out;
303 if (strcmp(*w, "random")) {
304 mi->random_score = 0;
305 ret = para_atoi32(*w, &mi->score_arg);
306 if (ret < 0)
307 goto out;
308 } else {
309 mi->random_score = 1;
310 if (!*(w + 1))
311 goto success; /* the line "score random" is valid */
312 }
313 } else
314 mi->score_arg = 0;
315 ret = -E_MOOD_SYNTAX;
316 w++;
317 if (!*w)
318 goto out;
319 check_for_if:
320 if (!strcmp(*w, "if")) {
321 ret = -E_MOOD_SYNTAX;
322 w++;
323 if (!*w)
324 goto out;
325 }
326 if (!strcmp(*w, "not")) {
327 ret = -E_MOOD_SYNTAX;
328 w++;
329 if (!*w)
330 goto out;
331 mi->logical_not = 1;
332 } else
333 mi->logical_not = 0;
334 for (i = 0; mood_methods[i].parser; i++) {
335 if (strcmp(*w, mood_methods[i].name))
336 continue;
337 break;
338 }
339 ret = -E_MOOD_SYNTAX;
340 if (!mood_methods[i].parser)
341 goto out;
342 ret = mood_methods[i].parser(num_words - 1 - (w - argv), w,
343 &mi->parser_data);
344 if (ret < 0)
345 goto out;
346 mi->method = &mood_methods[i];
347 success:
348 if (mlpd->m) {
349 if (mlt == ML_ACCEPT)
350 para_list_add(&mi->mood_item_node, &mlpd->m->accept_list);
351 else if (mlt == ML_DENY)
352 para_list_add(&mi->mood_item_node, &mlpd->m->deny_list);
353 else
354 para_list_add(&mi->mood_item_node, &mlpd->m->score_list);
355 }
356 PARA_DEBUG_LOG("%s entry added, method: %p\n", mlt == ML_ACCEPT? "accept" :
357 (mlt == ML_DENY? "deny" : "score"), mi->method);
358 ret = 1;
359 out:
360 free_argv(argv);
361 if (ret >= 0)
362 return ret;
363 if (mi) {
364 free(mi->parser_data);
365 free(mi);
366 }
367 return ret;
368 }
369
370 static int load_mood(const struct osl_row *mood_row, struct mood **m)
371 {
372 char *mood_name;
373 struct osl_object mood_def;
374 struct mood_line_parser_data mlpd = {.line_num = 0};
375 int ret;
376
377 *m = NULL;
378 ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
379 if (ret < 0)
380 return ret;
381 if (!*mood_name)
382 return -E_DUMMY_ROW;
383 mlpd.m = alloc_new_mood(mood_name);
384 ret = for_each_line_ro(mood_def.data, mood_def.size,
385 parse_mood_line, &mlpd);
386 osl_close_disk_object(&mood_def);
387 if (ret < 0) {
388 PARA_ERROR_LOG("unable to load mood %s: %s\n", mlpd.m->name,
389 para_strerror(-ret));
390 destroy_mood(mlpd.m);
391 return ret;
392 }
393 *m = mlpd.m;
394 return 1;
395 }
396
397 static int check_mood(struct osl_row *mood_row, void *data)
398 {
399 struct para_buffer *pb = data;
400 char *mood_name;
401 struct osl_object mood_def;
402 struct mood_line_parser_data mlpd = {.line_num = 0};
403
404 int ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
405
406 if (ret < 0) {
407 para_printf(pb, "failed to get mood definition: %s\n",
408 para_strerror(-ret));
409 return ret;
410 }
411 if (!*mood_name) /* ignore dummy row */
412 goto out;
413 ret = para_printf(pb, "checking mood %s...\n", mood_name);
414 if (ret < 0)
415 goto out;
416 ret = for_each_line_ro(mood_def.data, mood_def.size,
417 parse_mood_line, &mlpd);
418 if (ret < 0)
419 para_printf(pb, "%s line %u: %s\n", mood_name, mlpd.line_num,
420 para_strerror(-ret));
421 out:
422 osl_close_disk_object(&mood_def);
423 return ret;
424 }
425
426 /**
427 * Check all moods for syntax errors.
428 *
429 * \param fd The afs socket.
430 * \param query Unused.
431 */
432 void mood_check_callback(int fd, __a_unused const struct osl_object *query)
433 {
434 struct para_buffer pb = {
435 .max_size = shm_get_shmmax(),
436 .private_data = &(struct afs_max_size_handler_data) {
437 .fd = fd,
438 .band = SBD_OUTPUT
439 },
440 .max_size_handler = afs_max_size_handler
441 };
442
443 int ret = para_printf(&pb, "checking moods...\n");
444 if (ret < 0)
445 return;
446 osl_rbtree_loop(moods_table, BLOBCOL_ID, &pb,
447 check_mood);
448 if (pb.offset)
449 pass_buffer_as_shm(fd, SBD_OUTPUT, pb.buf, pb.offset);
450 free(pb.buf);
451 }
452
453 #if 0
454 static unsigned int_log2(uint64_t x)
455 {
456 unsigned res = 0;
457
458 while (x) {
459 x /= 2;
460 res++;
461 }
462 return res;
463 }
464 #endif
465
466 static int64_t normalized_value(int64_t x, int64_t n, int64_t sum, int64_t qd)
467 {
468 if (!n || !qd)
469 return 0;
470 return 100 * (n * x - sum) / (int64_t)int_sqrt(n * qd);
471 }
472
473 static long compute_num_played_score(struct afs_info *afsi)
474 {
475 return -normalized_value(afsi->num_played, statistics.num,
476 statistics.num_played_sum, statistics.num_played_qd);
477 }
478
479 static long compute_last_played_score(struct afs_info *afsi)
480 {
481 return -normalized_value(afsi->last_played, statistics.num,
482 statistics.last_played_sum, statistics.last_played_qd);
483 }
484
485 static long compute_dynamic_score(const struct osl_row *aft_row)
486 {
487 struct afs_info afsi;
488 int64_t score, nscore = 0, lscore = 0;
489 int ret;
490
491 ret = get_afsi_of_row(aft_row, &afsi);
492 if (ret < 0)
493 return -100;
494 nscore = compute_num_played_score(&afsi);
495 lscore = compute_last_played_score(&afsi);
496 score = nscore + lscore;
497 return score;
498 }
499
500 static int add_afs_statistics(const struct osl_row *row)
501 {
502 uint64_t n, x, s;
503 struct afs_info afsi;
504 int ret;
505
506 ret = get_afsi_of_row(row, &afsi);
507 if (ret < 0)
508 return ret;
509 n = statistics.num;
510 x = afsi.last_played;
511 s = statistics.last_played_sum;
512 if (n > 0)
513 statistics.last_played_qd += (x - s / n) * (x - s / n) * n / (n + 1);
514 statistics.last_played_sum += x;
515
516 x = afsi.num_played;
517 s = statistics.num_played_sum;
518 if (n > 0)
519 statistics.num_played_qd += (x - s / n) * (x - s / n) * n / (n + 1);
520 statistics.num_played_sum += x;
521 statistics.num++;
522 return 1;
523 }
524
525 static int del_afs_statistics(const struct osl_row *row)
526 {
527 uint64_t n, s, q, a, new_s;
528 struct afs_info afsi;
529 int ret;
530 ret = get_afsi_of_row(row, &afsi);
531 if (ret < 0)
532 return ret;
533 n = statistics.num;
534 assert(n);
535 if (n == 1) {
536 memset(&statistics, 0, sizeof(statistics));
537 return 1;
538 }
539
540 s = statistics.last_played_sum;
541 q = statistics.last_played_qd;
542 a = afsi.last_played;
543 new_s = s - a;
544 statistics.last_played_sum = new_s;
545 statistics.last_played_qd = q + s * s / n - a * a
546 - new_s * new_s / (n - 1);
547
548 s = statistics.num_played_sum;
549 q = statistics.num_played_qd;
550 a = afsi.num_played;
551 new_s = s - a;
552 statistics.num_played_sum = new_s;
553 statistics.num_played_qd = q + s * s / n - a * a
554 - new_s * new_s / (n - 1);
555
556 statistics.num--;
557 return 1;
558 }
559
560 /**
561 * Structure used during mood_open().
562 *
563 * At mood open time, we look at each file in the audio file table in order to
564 * determine whether it is admissible. If a file happens to be admissible, its
565 * mood score is computed by calling each relevant mood_score_function. Next,
566 * we update the afs_statistics and add a struct admissible_file_info to a
567 * temporary array.
568 *
569 * If all files have been processed that way, the final score of each
570 * admissible file is computed by adding the dynamic score (which depends on
571 * the afs_statistics) to the mood score. Finally, all audio files in the
572 * array are added to the score table and the admissible array is freed.
573 *
574 * \sa mood_method, admissible_array.
575 */
576 struct admissible_file_info
577 {
578 /** The admissible audio file. */
579 struct osl_row *aft_row;
580 /** Its score. */
581 long score;
582 };
583
584 /** The temporary array of admissible files. */
585 struct admissible_array {
586 /** Files are admissible wrt. this mood. */
587 struct mood *m;
588 /** The size of the array */
589 unsigned size;
590 /** Pointer to the array of admissible files. */
591 struct admissible_file_info *array;
592 };
593
594 /**
595 * Add an entry to the array of admissible files.
596 *
597 * \param aft_row The audio file to be added.
598 * \param private_data Pointer to a struct admissible_file_info.
599 *
600 * \return 1 if row admissible, 0 if not, negative on errors.
601 */
602 static int add_if_admissible(struct osl_row *aft_row, void *data)
603 {
604 struct admissible_array *aa = data;
605 int ret;
606 long score = 0;
607
608 ret = compute_mood_score(aft_row, aa->m, &score);
609 if (ret <= 0)
610 return ret;
611 if (statistics.num >= aa->size) {
612 aa->size *= 2;
613 aa->size += 100;
614 aa->array = para_realloc(aa->array,
615 aa->size * sizeof(struct admissible_file_info));
616 }
617 aa->array[statistics.num].aft_row = aft_row;
618 aa->array[statistics.num].score = score;
619 ret = add_afs_statistics(aft_row);
620 if (ret < 0)
621 return ret;
622 return 1;
623 }
624
625 /**
626 * Compute the new quadratic deviation in case one element changes.
627 *
628 * \param n Number of elements.
629 * \param old_qd The quadratic deviation before the change.
630 * \param old_val The value that was replaced.
631 * \param new_val The replacement value.
632 * \param old_sum The sum of all elements before the update.
633 *
634 * \return The new quadratic deviation resulting from replacing old_val
635 * by new_val.
636 *
637 * Given n real numbers a_1, ..., a_n, their sum S = a_1 + ... + a_n,
638 * their quadratic deviation
639 *
640 * q = (a_1 - S/n)^2 + ... + (a_n - S/n)^2,
641 *
642 * and a real number b, the quadratic deviation q' of a_1,...a_{n-1}, b (ie.
643 * the last number a_n was replaced by b) may be computed in O(1) time in terms
644 * of n, q, a_n, b, and S as
645 *
646 * q' = q + d * s - (2 * S + d) * d / n,
647 *
648 * where d = b - a_n, and s = b + a_n.
649 *
650 * Example: n = 3, a_1 = 3, a_2 = 5, a_3 = 7, b = 10. Then S = 15, q = 8, d = 3,
651 * s = 17, so
652 *
653 * q + d * s - (2 * S + d) * d / n = 8 + 51 - 33 = 26,
654 *
655 * which equals q' = (3 - 6)^2 + (5 - 6)^2 + (10 - 6)^2.
656 *
657 */
658 _static_inline_ int64_t update_quadratic_deviation(int64_t n, int64_t old_qd,
659 int64_t old_val, int64_t new_val, int64_t old_sum)
660 {
661 int64_t delta = new_val - old_val;
662 int64_t sigma = new_val + old_val;
663 return old_qd + delta * sigma - (2 * old_sum + delta) * delta / n;
664 }
665
666 static int update_afs_statistics(struct afs_info *old_afsi, struct afs_info *new_afsi)
667 {
668 unsigned n;
669 int ret = get_num_admissible_files(&n);
670
671 if (ret < 0)
672 return ret;
673 assert(n);
674
675 statistics.last_played_qd = update_quadratic_deviation(n,
676 statistics.last_played_qd, old_afsi->last_played,
677 new_afsi->last_played, statistics.last_played_sum);
678 statistics.last_played_sum += new_afsi->last_played - old_afsi->last_played;
679
680 statistics.num_played_qd = update_quadratic_deviation(n,
681 statistics.num_played_qd, old_afsi->num_played,
682 new_afsi->num_played, statistics.num_played_sum);
683 statistics.num_played_sum += new_afsi->num_played - old_afsi->num_played;
684 return 1;
685 }
686
687 static int add_to_score_table(const struct osl_row *aft_row, long mood_score)
688 {
689 long score = (compute_dynamic_score(aft_row) + mood_score) / 3;
690 return score_add(aft_row, score);
691 }
692
693 static int delete_from_statistics_and_score_table(const struct osl_row *aft_row)
694 {
695 int ret = del_afs_statistics(aft_row);
696 if (ret < 0)
697 return ret;
698 return score_delete(aft_row);
699 }
700
701 /**
702 * Delete one entry from the statistics and from the score table.
703 *
704 * \param aft_row The audio file which is no longer admissible.
705 *
706 * \return Positive on success, negative on errors.
707 *
708 * \sa score_delete().
709 */
710 static int mood_delete_audio_file(const struct osl_row *aft_row)
711 {
712 int ret;
713
714 ret = row_belongs_to_score_table(aft_row, NULL);
715 if (ret < 0)
716 return ret;
717 if (!ret) /* not admissible, nothing to do */
718 return 1;
719 return delete_from_statistics_and_score_table(aft_row);
720 }
721
722 /**
723 * Compute the new score of an audio file wrt. the current mood.
724 *
725 * \param aft_row Determines the audio file.
726 * \param old_afsi The audio file selector info before updating.
727 *
728 * The \a old_afsi argument may be \p NULL which indicates that no changes to
729 * the audio file info were made.
730 *
731 * \return Positive on success, negative on errors.
732 */
733 static int mood_update_audio_file(const struct osl_row *aft_row,
734 struct afs_info *old_afsi)
735 {
736 long score, percent;
737 int ret, is_admissible, was_admissible = 0;
738 struct afs_info afsi;
739 unsigned rank;
740
741 if (!current_mood)
742 return 1; /* nothing to do */
743 ret = row_belongs_to_score_table(aft_row, &rank);
744 if (ret < 0)
745 return ret;
746 was_admissible = ret;
747 ret = compute_mood_score(aft_row, current_mood, &score);
748 if (ret < 0)
749 return ret;
750 is_admissible = (ret > 0);
751 if (!was_admissible && !is_admissible)
752 return 1;
753 if (was_admissible && !is_admissible)
754 return delete_from_statistics_and_score_table(aft_row);
755 if (!was_admissible && is_admissible) {
756 ret = add_afs_statistics(aft_row);
757 if (ret < 0)
758 return ret;
759 return add_to_score_table(aft_row, score);
760 }
761 /* update score */
762 ret = get_afsi_of_row(aft_row, &afsi);
763 if (ret < 0)
764 return ret;
765 if (old_afsi) {
766 ret = update_afs_statistics(old_afsi, &afsi);
767 if (ret < 0)
768 return ret;
769 }
770 score += compute_num_played_score(&afsi);
771 score += compute_last_played_score(&afsi);
772 score /= 3;
773 PARA_DEBUG_LOG("score: %li\n", score);
774 percent = (score + 100) / 3;
775 if (percent > 100)
776 percent = 100;
777 else if (percent < 0)
778 percent = 0;
779 PARA_DEBUG_LOG("moving from rank %u to %lu%%\n", rank, percent);
780 return score_update(aft_row, percent);
781 }
782
783 static void log_statistics(void)
784 {
785 unsigned n = statistics.num;
786
787 if (!n) {
788 PARA_NOTICE_LOG("no admissible files\n");
789 return;
790 }
791 PARA_INFO_LOG("last_played mean: %lli, last_played sigma: %llu\n",
792 (long long int)(statistics.last_played_sum / n),
793 (long long unsigned)int_sqrt(statistics.last_played_qd / n));
794 PARA_INFO_LOG("num_played mean: %lli, num_played sigma: %llu\n",
795 (long long int)statistics.num_played_sum / n,
796 (long long unsigned)int_sqrt(statistics.num_played_qd / n));
797 }
798
799 /**
800 * Close the current mood.
801 *
802 * Free all resources of the current mood which were allocated during
803 * mood_open().
804 */
805 void close_current_mood(void)
806 {
807 destroy_mood(current_mood);
808 current_mood = NULL;
809 memset(&statistics, 0, sizeof(statistics));
810 }
811
812 /**
813 * Change the current mood.
814 *
815 * \param mood_name The name of the mood to open.
816 *
817 * If \a mood_name is \a NULL, load the dummy mood that accepts every audio file
818 * and uses a scoring method based only on the \a last_played information.
819 *
820 * If there is already an open mood, it will be closed first.
821 *
822 * \return Positive on success, negative on errors. Loading the dummy mood
823 * always succeeds.
824 *
825 * \sa struct admissible_file_info, struct admissible_array, struct
826 * afs_info::last_played, mood_close().
827 */
828 int change_current_mood(char *mood_name)
829 {
830 int i, ret;
831 struct admissible_array aa = {
832 .size = 0,
833 .array = NULL
834 };
835
836 if (mood_name) {
837 struct mood *m;
838 struct osl_row *row;
839 struct osl_object obj = {
840 .data = mood_name,
841 .size = strlen(mood_name) + 1
842 };
843 ret = osl(osl_get_row(moods_table, BLOBCOL_NAME, &obj, &row));
844 if (ret < 0) {
845 PARA_NOTICE_LOG("no such mood: %s\n", mood_name);
846 return ret;
847 }
848 ret = load_mood(row, &m);
849 if (ret < 0)
850 return ret;
851 close_current_mood();
852 current_mood = m;
853 } else {
854 close_current_mood();
855 current_mood = alloc_new_mood("dummy");
856 }
857 aa.m = current_mood;
858 PARA_NOTICE_LOG("computing statistics of admissible files\n");
859 ret = audio_file_loop(&aa, add_if_admissible);
860 if (ret < 0)
861 return ret;
862 log_statistics();
863 PARA_INFO_LOG("%d admissible files \n", statistics.num);
864 for (i = 0; i < statistics.num; i++) {
865 struct admissible_file_info *a = aa.array + i;
866 ret = add_to_score_table(a->aft_row, a->score);
867 if (ret < 0)
868 goto out;
869 }
870 PARA_NOTICE_LOG("loaded mood %s\n", current_mood->name);
871 ret = statistics.num;
872 out:
873 free(aa.array);
874 return ret;
875 }
876 /**
877 * Close and re-open the current mood.
878 *
879 * This function is used if changes to the audio file table or the
880 * attribute table were made that render the current list of admissible
881 * files useless. For example, if an attribute is removed from the
882 * attribute table, this function is called.
883 *
884 * \return Positive on success, negative on errors. If no mood is currently
885 * open, the function returns success.
886 *
887 * \sa mood_open(), mood_close().
888 */
889 static int reload_current_mood(void)
890 {
891 int ret;
892 char *mood_name = NULL;
893
894 if (!current_mood)
895 return 1;
896 PARA_NOTICE_LOG("reloading %s\n", current_mood->name?
897 current_mood->name : "(dummy)");
898 if (current_mood->name)
899 mood_name = para_strdup(current_mood->name);
900 close_current_mood();
901 ret = change_current_mood(mood_name);
902 free(mood_name);
903 return ret;
904 }
905
906 /**
907 * Notification callback for the moods table.
908 *
909 * \param event Type of the event just occurred.
910 * \param pb Unused.
911 * \param data Its type depends on the event.
912 *
913 * This function performs actions required due to the occurrence of the given
914 * event. Possible actions include reload of the current mood and update of the
915 * score of an audio file.
916 */
917 int moods_event_handler(enum afs_events event, __a_unused struct para_buffer *pb,
918 void *data)
919 {
920 int ret;
921
922 if (!current_mood)
923 return 0;
924 switch (event) {
925 /*
926 * The three blob events might change the set of admissible files,
927 * so we must reload the score list.
928 */
929 case BLOB_RENAME:
930 case BLOB_REMOVE:
931 case BLOB_ADD:
932 if (data == moods_table || data == playlists_table)
933 return 1; /* no reload necessary for these */
934 ret = clear_score_table();
935 if (ret < 0)
936 PARA_CRIT_LOG("clear score table returned %s\n",
937 para_strerror(-ret));
938 return reload_current_mood();
939 /* these also require reload of the score table */
940 case ATTRIBUTE_ADD:
941 case ATTRIBUTE_REMOVE:
942 case ATTRIBUTE_RENAME:
943 return reload_current_mood();
944 /* changes to the aft only require to re-examine the audio file */
945 case AFSI_CHANGE: {
946 struct afsi_change_event_data *aced = data;
947 return mood_update_audio_file(aced->aft_row, aced->old_afsi);
948 }
949 case AFHI_CHANGE:
950 case AUDIO_FILE_RENAME:
951 case AUDIO_FILE_ADD:
952 return mood_update_audio_file(data, NULL);
953 case AUDIO_FILE_REMOVE:
954 return mood_delete_audio_file(data);
955 default:
956 return 1;
957 }
958 }