1;;;; This file is part of LilyPond, the GNU music typesetter.
2;;;;
3;;;; Copyright (C) 2004--2021 Han-Wen Nienhuys <hanwen@xs4all.nl>
4;;;;
5;;;; LilyPond is free software: you can redistribute it and/or modify
6;;;; it under the terms of the GNU General Public License as published by
7;;;; the Free Software Foundation, either version 3 of the License, or
8;;;; (at your option) any later version.
9;;;;
10;;;; LilyPond is distributed in the hope that it will be useful,
11;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
12;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13;;;; GNU General Public License for more details.
14;;;;
15;;;; You should have received a copy of the GNU General Public License
16;;;; along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
17
18;; todo: figure out how to make module,
19;; without breaking nested ly scopes
20
21(define-class <Voice-state> ()
22  (event-list #:init-value '() #:accessor events #:init-keyword #:events)
23  (when-moment #:accessor moment #:init-keyword #:moment)
24  (tuning #:accessor tuning #:init-keyword #:tuning)
25  (split-index #:accessor split-index)
26  (vector-index)
27  (state-vector)
28  ;;;
29  ;; spanner-state is an alist
30  ;; of (SYMBOL . RESULT-INDEX), which indicates where
31  ;; said spanner was started.
32  (spanner-state #:init-value '() #:accessor span-state))
33
34(define-method (write (x <Voice-state> ) file)
35  (display (moment x) file)
36  (display " evs = " file)
37  (display (events x) file)
38  (display " active = " file)
39  (display (span-state x) file)
40  (display "\n" file))
41
42;; Return the duration of the longest event in the Voice-state.
43(define-method (duration (vs <Voice-state>))
44  (define (duration-max event d1)
45    (let ((d2 (ly:event-property event 'duration #f)))
46      (if d2
47          (if (ly:duration<? d1 d2) d2 d1)
48          d1)))
49
50  (fold duration-max ZERO-DURATION (events vs)))
51
52(define-method (note-events (vs <Voice-state>))
53  (define (f? x)
54    (ly:in-event-class? x 'note-event))
55  (filter f? (events vs)))
56
57;; Return a list of note events which is sorted and stripped of
58;; properties that we do not want to prevent combining parts.
59(define-method (comparable-note-events (vs <Voice-state>))
60  (define (note<? note1 note2)
61    (let ((p1 (ly:event-property note1 'pitch))
62          (p2 (ly:event-property note2 'pitch)))
63      (cond ((ly:pitch<? p1 p2) #t)
64            ((ly:pitch<? p2 p1) #f)
65            (else (ly:duration<? (ly:event-property note1 'duration)
66                                 (ly:event-property note2 'duration))))))
67  ;; TODO we probably should compare articulations too
68  (sort (map (lambda (x)
69               (ly:make-stream-event
70                (ly:make-event-class 'note-event)
71                (list (cons 'duration (ly:event-property x 'duration))
72                      (cons 'pitch (ly:event-property x 'pitch)))))
73             (note-events vs))
74        note<?))
75
76(define-method (silence-events (vs <Voice-state>))
77  (let ((result (filter (lambda(x)
78                          (or (ly:in-event-class? x 'rest-event)
79                              (ly:in-event-class? x 'multi-measure-rest-event)))
80                        (events vs))))
81    ;; There may be skips in the same part with rests for various
82    ;; reasons.  Regard the skips only if there are no rests.
83    (if (not (pair? result))
84        (set! result (filter (lambda(x) (ly:in-event-class? x 'skip-event))
85                             (events vs))))
86    result))
87
88(define-method (any-mmrest-events (vs <Voice-state>))
89  (define (f? x)
90    (ly:in-event-class? x 'multi-measure-rest-event))
91  (any f? (events vs)))
92
93(define-method (previous-voice-state (vs <Voice-state>))
94  (let ((i (slot-ref vs 'vector-index))
95        (v (slot-ref vs 'state-vector)))
96    (if (< 0 i)
97        (vector-ref v (1- i))
98        #f)))
99
100;; true if the part has ended
101(define-method (done? (vs <Voice-state>))
102  (let ((i (slot-ref vs 'vector-index))
103        (v (slot-ref vs 'state-vector)))
104    ;; the last entry represents the end of the part
105    (= (1+ i) (vector-length v))))
106
107;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
108
109(define-class <Split-state> ()
110  ;; The automatically determined split configuration
111  (configuration #:init-value '() #:accessor configuration)
112  ;; Allow overriding split configuration, takes precedence over configuration
113  (forced-configuration #:init-value #f #:accessor forced-configuration)
114  (when-moment #:accessor moment #:init-keyword #:moment)
115  ;; voice-states are states starting with the Split-state or later
116  ;;
117  (is #:init-keyword #:voice-states #:accessor voice-states)
118  (synced  #:init-keyword #:synced #:init-value  #f #:getter synced?))
119
120
121(define-method (write (x <Split-state> ) f)
122  (display (moment x) f)
123  (display " = " f)
124  (display (configuration x) f)
125  (if (synced? x)
126      (display " synced "))
127  (display "\n" f))
128
129(define-method (current-or-previous-voice-states (ss <Split-state>))
130  "Return voice states meeting the following conditions.  For a voice
131in sync, return the current voice state.  For a voice out of sync,
132return the previous voice state."
133  (let* ((vss (voice-states ss))
134         (vs1 (car vss))
135         (vs2 (cdr vss)))
136    (if (and vs1 (not (equal? (moment vs1) (moment ss))))
137        (set! vs1 (previous-voice-state vs1)))
138    (if (and vs2 (not (equal? (moment vs2) (moment ss))))
139        (set! vs2 (previous-voice-state vs2)))
140    (cons vs1 vs2)))
141
142;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
143
144
145(define (previous-span-state vs)
146  (let ((p (previous-voice-state vs)))
147    (if p (span-state p) '())))
148
149(define (make-voice-states evl)
150  (let* ((states (map (lambda (v)
151                        (make <Voice-state>
152                          #:moment (caar v)
153                          #:tuning (cdar v)
154                          #:events (map car (cdr v))))
155                      (reverse evl))))
156
157    ;; TODO: Add an entry at +inf.0 and see if it allows us to remove
158    ;; the many instances of conditional code handling the case that
159    ;; there is no voice state at a given moment.
160
161    (let ((vec (list->vector (reverse! states))))
162      (do ((i 0 (1+ i)))
163          ((= i (vector-length vec)) vec)
164        (slot-set! (vector-ref vec i) 'vector-index i)
165        (slot-set! (vector-ref vec i) 'state-vector vec)))))
166
167(define (make-split-state vs1 vs2)
168  "Merge lists VS1 and VS2, containing Voice-state objects into vector
169of Split-state objects, crosslinking the Split-state vector and
170Voice-state objects
171"
172  (define (helper ss-idx ss-list idx1 idx2)
173    (let* ((state1 (if (< idx1 (vector-length vs1)) (vector-ref vs1 idx1) #f))
174           (state2 (if (< idx2 (vector-length vs2)) (vector-ref vs2 idx2) #f))
175           (min (cond ((and state1 state2) (moment-min (moment state1) (moment state2)))
176                      (state1 (moment state1))
177                      (state2 (moment state2))
178                      (else #f)))
179           (inc1 (if (and state1 (equal? min (moment state1))) 1 0))
180           (inc2 (if (and state2 (equal? min (moment state2))) 1 0))
181           (ss-object (if min
182                          (make <Split-state>
183                            #:moment min
184                            #:voice-states (cons state1 state2)
185                            #:synced (= inc1 inc2))
186                          #f)))
187      (if state1
188          (set! (split-index state1) ss-idx))
189      (if state2
190          (set! (split-index state2) ss-idx))
191      (if min
192          (helper (1+ ss-idx)
193                  (cons ss-object ss-list)
194                  (+ idx1 inc1)
195                  (+ idx2 inc2))
196          ss-list)))
197  (list->vector (reverse! (helper 0 '() 0  0) '())))
198
199(define (analyse-spanner-states voice-state-vec)
200
201  (define (helper index active)
202    "Analyse EVS at INDEX, given state ACTIVE."
203
204    (define (analyse-tie-start active ev)
205      (if (ly:in-event-class? ev 'tie-event)
206          (acons 'tie (split-index (vector-ref voice-state-vec index))
207                 active)
208          active))
209
210    (define (analyse-tie-end active ev)
211      (if (ly:in-event-class? ev 'note-event)
212          (assoc-remove! active 'tie)
213          active))
214
215    (define (analyse-absdyn-end active ev)
216      (if (or (ly:in-event-class? ev 'absolute-dynamic-event)
217              (and (ly:in-event-class? ev 'span-dynamic-event)
218                   (equal? STOP (ly:event-property ev 'span-direction))))
219          (assoc-remove! (assoc-remove! active 'cresc) 'decr)
220          active))
221
222    (define (active<? a b)
223      (cond ((symbol<? (car a) (car b)) #t)
224            ((symbol<? (car b) (car a)) #f)
225            (else (< (cdr a) (cdr b)))))
226
227    (define (analyse-span-event active ev)
228      (let* ((name (car (ly:event-property ev 'class)))
229             (key (cond ((equal? name 'slur-event) 'slur)
230                        ((equal? name 'phrasing-slur-event) 'tie)
231                        ((equal? name 'beam-event) 'beam)
232                        ((equal? name 'crescendo-event) 'cresc)
233                        ((equal? name 'decrescendo-event) 'decr)
234                        (else #f)))
235             (sp (ly:event-property ev 'span-direction)))
236        (if (and (symbol? key) (ly:dir? sp))
237            (if (= sp STOP)
238                (assoc-remove! active key)
239                (acons key
240                       (split-index (vector-ref voice-state-vec index))
241                       active))
242            active)))
243
244    (define (analyse-events active evs)
245      "Run all analyzers on ACTIVE and EVS"
246      (define (run-analyzer analyzer active evs)
247        (if (pair? evs)
248            (run-analyzer analyzer (analyzer active (car evs)) (cdr evs))
249            active))
250      (define (run-analyzers analyzers active evs)
251        (if (pair? analyzers)
252            (run-analyzers (cdr analyzers)
253                           (run-analyzer (car analyzers) active evs)
254                           evs)
255            active))
256      (sort ;; todo: use fold or somesuch.
257       (run-analyzers (list analyse-absdyn-end analyse-span-event
258                            ;; note: tie-start/span comes after tie-end/absdyn.
259                            analyse-tie-end analyse-tie-start)
260                      active evs)
261       active<?))
262
263    ;; must copy, since we use assoc-remove!
264    (if (< index (vector-length voice-state-vec))
265        (begin
266          (set! active (analyse-events active (events (vector-ref voice-state-vec index))))
267          (set! (span-state (vector-ref voice-state-vec index))
268                (list-copy active))
269          (helper (1+ index) active))))
270
271  (helper 0 '()))
272
273(define recording-group-functions
274  ;;Selected parts from @var{toplevel-music-functions} not requiring @code{parser}.
275  (list
276   (lambda (music) (expand-repeat-chords! '(rhythmic-event) music))
277   expand-repeat-notes!))
278
279
280;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
281(define-public (recording-group-emulate music odef)
282  "Interpret @var{music} according to @var{odef}, but store all events
283in a chronological list, similar to the @code{Recording_group_engraver} in
284LilyPond version 2.8 and earlier."
285  (let*
286      ((context-list '())
287       (now-mom (ly:make-moment 0 0))
288       (global (ly:make-global-context odef))
289       (mom-listener (lambda (tev) (set! now-mom (ly:event-property tev 'moment))))
290       (new-context-listener
291        (lambda (sev)
292          (let*
293              ((child (ly:event-property sev 'context))
294               (this-moment-list (cons (ly:context-id child) '()))
295               (dummy (set! context-list (cons this-moment-list context-list)))
296               (acc '())
297               (accumulate-event-listener
298                (lambda (ev)
299                  (set! acc (cons (cons ev #t) acc))))
300               (remove-context-listener
301                (lambda (ev)
302                  "Add a final entry to record the end moment."
303                  (let ((this-moment (cons (cons
304                                            now-mom
305                                            #f ; instrumentTransposition
306                                            )
307                                           '() ; events
308                                           )))
309                    (set-cdr! this-moment-list
310                              (cons this-moment (cdr this-moment-list))))))
311               (save-acc-listener
312                (lambda (tev)
313                  (if (pair? acc)
314                      (let ((this-moment
315                             (cons (cons now-mom
316                                         (ly:context-property child 'instrumentTransposition))
317                                   ;; The accumulate-event-listener above creates
318                                   ;; the list of events in reverse order, so we
319                                   ;; have to revert it to the original order again
320                                   (reverse acc))))
321                        (set-cdr! this-moment-list
322                                  (cons this-moment (cdr this-moment-list)))
323                        (set! acc '()))))))
324            (ly:add-listener accumulate-event-listener
325                             (ly:context-event-source child) 'StreamEvent)
326            (ly:add-listener remove-context-listener
327                             (ly:context-event-source child) 'RemoveContext)
328            (ly:add-listener save-acc-listener
329                             (ly:context-event-source global) 'OneTimeStep)))))
330    (ly:add-listener new-context-listener
331                     (ly:context-events-below global) 'AnnounceNewContext)
332    (ly:add-listener mom-listener (ly:context-event-source global) 'Prepare)
333    (ly:interpret-music-expression
334     (make-non-relative-music
335      (fold (lambda (x m) (x m)) music recording-group-functions))
336     global)
337    context-list))
338
339(define-public (determine-split-list evl1 evl2 chord-range)
340  "Event lists @var{evl1} and @var{evl2} should be ascending.
341@var{chord-range} is a pair of numbers @code{(min . max)} defining the distance
342in steps between notes that may be combined into a chord or unison."
343  (let* ((pc-debug #f)
344         (voice-state-vec1 (make-voice-states evl1))
345         (voice-state-vec2 (make-voice-states evl2))
346         (result (make-split-state voice-state-vec1 voice-state-vec2))
347         (chord-min-diff (car chord-range))
348         (chord-max-diff (cdr chord-range)))
349
350    ;; Go through all moments recursively and check if the events of that
351    ;; moment contain a part-combine-force-event override. If so, store its
352    ;; value in the forced-configuration field, which will override. The
353    ;; previous configuration is used to determine non-terminated settings.
354    (define (analyse-forced-combine result-idx prev-res)
355
356      (define (get-forced-event x)
357        (cond
358         ((and (ly:in-event-class? x 'SetProperty)
359               (eq? (ly:event-property x 'symbol) 'partCombineForced))
360          (cons (ly:event-property x 'value #f)
361                (ly:event-property x 'once #f)))
362         ((and (ly:in-event-class? x 'UnsetProperty)
363               (eq? (ly:event-property x 'symbol) 'partCombineForced))
364          (cons #f (ly:event-property x 'once #f)))
365         (else #f)))
366
367      (define (part-combine-events vs)
368        (if (not vs)
369            '()
370            (filter-map get-forced-event (events vs))))
371      ;; end part-combine-events
372
373      ;; forced-result: Take the previous config and analyse whether
374      ;; any change happened.... Return new once and permanent config
375      (define (forced-result evt state)
376        ;; sanity check, evt should always be (new-state . once)
377        (if (not (and (pair? evt) (pair? state)))
378            state
379            (if (cdr evt)
380                ;; Once-event, leave permanent state unchanged
381                (cons (car evt) (cdr state))
382                ;; permanent change, leave once state unchanged
383                (cons (car state) (car evt)))))
384      ;; end forced-combine-result
385
386      ;; body of analyse-forced-combine:
387      (if (< result-idx (vector-length result))
388          (let* ((now-state (vector-ref result result-idx)) ; current result
389                 ;; Extract all part-combine force events
390                 (evts (if (synced? now-state)
391                           (append
392                            (part-combine-events (car (voice-states now-state)))
393                            (part-combine-events (cdr (voice-states now-state))))
394                           '()))
395                 ;; result is (once-state permament-state):
396                 (state (fold forced-result (cons 'automatic prev-res) evts))
397                 ;; Now let once override permanent changes:
398                 (force-state (if (equal? (car state) 'automatic)
399                                  (cdr state)
400                                  (car state))))
401            (set! (forced-configuration (vector-ref result result-idx))
402                  force-state)
403            ;; For the next moment, ignore the once override (car stat)
404            ;; and pass on the permanent override, stored as (cdr state)
405            (analyse-forced-combine (1+ result-idx) (cdr state)))))
406    ;; end analyse-forced-combine
407
408
409    (define (analyse-time-step result-idx)
410      (define (put x . index)
411        "Put the result to X, starting from INDEX backwards.
412
413Only set if not set previously.
414"
415        (let ((i (if (pair? index) (car index) result-idx)))
416          (if (and (<= 0 i)
417                   (not (symbol? (configuration (vector-ref result i)))))
418              (begin
419                (set! (configuration (vector-ref result i)) x)
420                (put x (1- i))))))
421
422      (define (copy-state-from state-vec vs)
423        (define (copy-one-state key-idx)
424          (let* ((idx (cdr key-idx))
425                 (prev-ss (vector-ref result idx))
426                 (prev (configuration prev-ss)))
427            (if (symbol? prev)
428                (put prev))))
429        (for-each copy-one-state (span-state vs)))
430
431      (define (analyse-notes now-state)
432        (let* ((vs1 (car (voice-states now-state)))
433               (vs2 (cdr (voice-states now-state)))
434               (notes1 (comparable-note-events vs1))
435               (notes2 (comparable-note-events vs2)))
436          (cond
437           ;; if neither part has notes, do nothing
438           ((and (not (pair? notes1)) (not (pair? notes2))))
439
440           ;; if one part has notes and the other does not
441           ((or (not (pair? notes1)) (not (pair? notes2))) (put 'apart))
442
443           ;; if either part has a chord
444           ((or (> (length notes1) 1)
445                (> (length notes2) 1))
446            (if (and (<= chord-min-diff 0) ; user requests combined unisons
447                     (equal? notes1 notes2)) ; both parts have the same chord
448                (put 'chords)
449                (put 'apart)))
450
451           ;; if the durations are different
452           ;; TODO articulations too?
453           ((and (not (equal? (ly:event-property (car notes1) 'duration)
454                              (ly:event-property (car notes2) 'duration))))
455            (put 'apart))
456
457           (else
458            ;; Is the interval outside of chord-range?
459            (if (let ((diff (ly:pitch-steps
460                             (ly:pitch-diff
461                              (ly:event-property (car notes1) 'pitch)
462                              (ly:event-property (car notes2) 'pitch)))))
463                  (or (< diff chord-min-diff)
464                      (> diff chord-max-diff)
465                      ))
466                (put 'apart)
467                ;; copy previous split state from spanner state
468                (begin
469                  (if (previous-voice-state vs1)
470                      (copy-state-from voice-state-vec1
471                                       (previous-voice-state vs1)))
472                  (if (previous-voice-state vs2)
473                      (copy-state-from voice-state-vec2
474                                       (previous-voice-state vs2)))
475                  (if (and (null? (span-state vs1)) (null? (span-state vs2)))
476                      (put 'chords))))))))
477
478      (if (< result-idx (vector-length result))
479          (let* ((now-state (vector-ref result result-idx))
480                 (vs1 (car (voice-states now-state)))
481                 (vs2 (cdr (voice-states now-state))))
482
483            (cond ((not vs1) (put 'apart))
484                  ((not vs2) (put 'apart))
485                  (else
486                   (let ((active1 (previous-span-state vs1))
487                         (active2 (previous-span-state vs2))
488                         (new-active1 (span-state vs1))
489                         (new-active2 (span-state vs2)))
490                     (if #f ; debug
491                         (display (list (moment now-state) result-idx
492                                        active1 "->" new-active1
493                                        active2 "->" new-active2
494                                        "\n")))
495                     (if (and (synced? now-state)
496                              (equal? active1 active2)
497                              (equal? new-active1 new-active2))
498                         (analyse-notes now-state)
499
500                         ;; active states different:
501                         (put 'apart)))
502
503                   ;; go to the next one, if it exists.
504                   (analyse-time-step (1+ result-idx)))))))
505
506    (define (analyse-a2 result-idx)
507      (if (< result-idx (vector-length result))
508          (let* ((now-state (vector-ref result result-idx))
509                 (vs1 (car (voice-states now-state)))
510                 (vs2 (cdr (voice-states now-state))))
511
512            (define (analyse-synced-silence)
513              (let ((rests1 (if vs1 (silence-events vs1) '()))
514                    (rests2 (if vs2 (silence-events vs2) '())))
515                (cond
516
517                 ;; equal rests or equal skips, but not one of each
518                 ((and (= 1 (length rests1))
519                       (= 1 (length rests2))
520                       (equal? (ly:event-property (car rests1) 'class)
521                               (ly:event-property (car rests2) 'class))
522                       (equal? (ly:event-property (car rests1) 'duration)
523                               (ly:event-property (car rests2) 'duration)))
524                  (set! (configuration now-state) 'unisilence))
525
526                 ;; rests of different durations or mixed with
527                 ;; skips or multi-measure rests
528                 (else
529                  ;; TODO For skips, route the rest to the shared
530                  ;; voice and the skip to the voice for its part?
531                  (set! (configuration now-state) 'apart-silence))
532
533                 )))
534
535            (define (analyse-unsynced-silence vs1 vs2)
536              (let ((any-mmrests1 (if vs1 (any-mmrest-events vs1) #f))
537                    (any-mmrests2 (if vs2 (any-mmrest-events vs2) #f)))
538                (cond
539                 ;; If a multi-measure rest begins now while the other
540                 ;; part has an ongoing multi-measure rest (or has
541                 ;; ended), start displaying the one that begins now.
542                 ((and any-mmrests1
543                       (equal? (moment vs1) (moment now-state))
544                       (or (not vs2) any-mmrests2))
545                  (set! (configuration now-state) 'silence1))
546
547                 ;; as above with parts swapped
548                 ((and any-mmrests2
549                       (equal? (moment vs2) (moment now-state))
550                       (or (not vs1) any-mmrests1))
551                  (set! (configuration now-state) 'silence2))
552                 )))
553
554            (if (or vs1 vs2)
555                (let ((notes1 (if vs1 (comparable-note-events vs1) '()))
556                      (notes2 (if vs2 (comparable-note-events vs2) '())))
557                  (cond ((and (equal? (configuration now-state) 'chords)
558                              (pair? notes1)
559                              (equal? notes1 notes2))
560                         (set! (configuration now-state) 'unisono))
561
562                        ((synced? now-state)
563                         (if (and (= 0 (length notes1))
564                                  (= 0 (length notes2)))
565                             (analyse-synced-silence)))
566
567                        (else ;; not synchronized
568                         (let* ((vss
569                                 (current-or-previous-voice-states now-state))
570                                (vs1 (car vss))
571                                (vs2 (cdr vss)))
572                           (if (and
573                                (or (not vs1) (= 0 (length (note-events vs1))))
574                                (or (not vs2) (= 0 (length (note-events vs2)))))
575                               (analyse-unsynced-silence vs1 vs2))))
576                        )))
577            (analyse-a2 (1+ result-idx)))))
578
579    (define (analyse-solo12 result-idx)
580
581      (define (previous-config vs)
582        (let* ((pvs (previous-voice-state vs))
583               (spi (if pvs (split-index pvs) #f))
584               (prev-split (if spi (vector-ref result spi) #f)))
585          (if prev-split
586              (configuration prev-split)
587              'apart)))
588
589      (define (put-range x a b)
590        ;; (display (list "put range "  x a b "\n"))
591        (do ((i a (1+ i)))
592            ((> i b) b)
593          (set! (configuration (vector-ref result i)) x)))
594
595      (define (put x)
596        ;; (display (list "putting "  x "\n"))
597        (set! (configuration (vector-ref result result-idx)) x))
598
599      (define (current-voice-state now-state voice-num)
600        (define vs ((if (= 1 voice-num) car cdr)
601                    (voice-states now-state)))
602        (if (or (not vs) (equal? (moment now-state) (moment vs)))
603            vs
604            (previous-voice-state vs)))
605
606      (define (try-solo type start-idx current-idx)
607        "Find a maximum stretch that can be marked as solo.  Only set
608the mark when there are no spanners active.
609
610      return next idx to analyse.
611"
612        (if (< current-idx (vector-length result))
613            (let* ((now-state (vector-ref result current-idx))
614                   (solo-state (current-voice-state now-state (if (equal? type 'solo1) 1 2)))
615                   (silent-state (current-voice-state now-state (if (equal? type 'solo1) 2 1)))
616                   (silent-notes (if silent-state (note-events silent-state) '()))
617                   (solo-notes (if solo-state (note-events solo-state) '())))
618              ;; (display (list "trying " type " at "  (moment now-state) solo-state silent-state        "\n"))
619              (cond ((not (equal? (configuration now-state) 'apart))
620                     current-idx)
621                    ((> (length silent-notes) 0) start-idx)
622                    ((not solo-state)
623                     (put-range type start-idx current-idx)
624                     current-idx)
625                    ((and
626                      (null? (span-state solo-state)))
627
628                     ;;
629                     ;; This includes rests. This isn't a problem: long rests
630                     ;; will be shared with the silent voice, and be marked
631                     ;; as unisilence. Therefore, long rests won't
632                     ;;  accidentally be part of a solo.
633                     ;;
634                     (put-range type start-idx current-idx)
635                     (try-solo type (1+ current-idx) (1+  current-idx)))
636                    (else
637                     (try-solo type start-idx (1+ current-idx)))))
638            ;; try-solo
639            start-idx))
640
641      (define (analyse-apart-silence result-idx)
642        "Analyse 'apart-silence starting at RESULT-IDX.  Return next index."
643
644        (define (analyse-synced-apart-silence vs1 vs2)
645          (let* ((rests1 (silence-events vs1))
646                 (rests2 (silence-events vs2)))
647            (cond
648             ;; multiple rests in the same part
649             ((and (or (not (= 1 (length rests1)))
650                       (not (= 1 (length rests2)))))
651              (put 'apart-silence))
652
653             ;; rest with multi-measure rest: choose the rest
654             ((and (ly:in-event-class? (car rests1) 'rest-event)
655                   (ly:in-event-class? (car rests2) 'multi-measure-rest-event))
656              (put 'silence1))
657
658             ;; as above with parts swapped
659             ((and (ly:in-event-class? (car rests1) 'multi-measure-rest-event)
660                   (ly:in-event-class? (car rests2) 'rest-event))
661              (put 'silence2))
662
663             ;; mmrest in both parts: choose the shorter one
664             ;; (equal mmrests are classified as unisilence earlier,
665             ;; so they shouldn't be seen here)
666             ((and (ly:in-event-class? (car rests1) 'multi-measure-rest-event)
667                   (ly:in-event-class? (car rests2) 'multi-measure-rest-event))
668              (if (ly:duration<? (ly:event-property (car rests1) 'duration)
669                                 (ly:event-property (car rests2) 'duration))
670                  (put 'silence1)
671                  (put 'silence2)))
672
673             (else
674              (put 'apart-silence)))))
675
676        (define (analyse-unsynced-apart-silence vs1 vs2)
677          (let* ((prev-state (if (> result-idx 0)
678                                 (vector-ref result (- result-idx 1))
679                                 #f))
680                 (prev-config (if prev-state
681                                  (configuration prev-state)
682                                  'apart-silence)))
683            (cond
684             ;; remain in the silence1/2 states until resync
685             ((equal? prev-config 'silence1)
686              (put 'silence1))
687
688             ((equal? prev-config 'silence2)
689              (put 'silence2))
690
691             (else
692              (put 'apart-silence)))))
693
694        (let* ((now-state (vector-ref result result-idx))
695               (vs1 (current-voice-state now-state 1))
696               (vs2 (current-voice-state now-state 2)))
697          (cond
698           ;; part 1 has ended
699           ((or (not vs1) (done? vs1))
700            (put 'silence2))
701
702           ;; part 2 has ended
703           ((or (not vs2) (done? vs2))
704            (put 'silence1))
705
706           ((synced? now-state)
707            (analyse-synced-apart-silence vs1 vs2))
708
709           (else
710            (analyse-unsynced-apart-silence vs1 vs2)))
711
712          (1+ result-idx)))
713
714      (define (analyse-apart result-idx)
715        "Analyse 'apart starting at RESULT-IDX.  Return next index."
716        (let* ((now-state (vector-ref result result-idx))
717               (vs1 (current-voice-state now-state 1))
718               (vs2 (current-voice-state now-state 2))
719               ;; (vs1 (car (voice-states now-state)))
720               ;; (vs2 (cdr (voice-states now-state)))
721               (notes1 (if vs1 (note-events vs1) '()))
722               (notes2 (if vs2 (note-events vs2) '()))
723               (n1 (length notes1))
724               (n2 (length notes2)))
725          ;; (display (list "analyzing step " result-idx "  moment " (moment now-state) vs1 vs2  "\n"))
726          (max
727           ;; we should always increase.
728           (cond ((and (= n1 0) (= n2 0))
729                  ;; If we hit this, it means that the previous passes
730                  ;; have designated as 'apart what is really
731                  ;; 'apart-silence.
732                  (analyse-apart-silence result-idx))
733                 ((and (= n2 0)
734                       (equal? (moment vs1) (moment now-state))
735                       (null? (previous-span-state vs1)))
736                  (try-solo 'solo1 result-idx result-idx))
737                 ((and (= n1 0)
738                       (equal? (moment vs2) (moment now-state))
739                       (null? (previous-span-state vs2)))
740                  (try-solo 'solo2 result-idx result-idx))
741
742                 (else (1+ result-idx)))
743           ;; analyse-moment
744           (1+ result-idx))))
745
746      (if (< result-idx (vector-length result))
747          (let ((conf (configuration (vector-ref result result-idx))))
748            (cond
749             ((equal? conf 'apart)
750              (analyse-solo12 (analyse-apart result-idx)))
751             ((equal? conf 'apart-silence)
752              (analyse-solo12 (analyse-apart-silence result-idx)))
753             (else
754              (analyse-solo12 (1+ result-idx))))))) ; analyse-solo12
755
756    (analyse-spanner-states voice-state-vec1)
757    (analyse-spanner-states voice-state-vec2)
758    (if #f
759        (begin
760          (display voice-state-vec1)
761          (display "***\n")
762          (display voice-state-vec2)
763          (display "***\n")
764          (display result)
765          (display "***\n")))
766
767    ;; Extract all forced combine strategies, i.e. events inserted by
768    ;; \partCombine(Apart|Automatic|SoloI|SoloII|Chords)[Once]
769    ;; They will in the end override the automaically determined ones.
770    ;; Initial state for both voices is no override
771    (analyse-forced-combine 0 #f)
772    ;; Now go through all time steps in a loop and find a combination strategy
773    ;; based only on the events of that one moment (i.e. neglecting longer
774    ;; periods of solo/apart, etc.)
775    (analyse-time-step 0)
776    ;; (display result)
777    ;; Check for unisono or unisilence moments
778    (analyse-a2 0)
779    ;;(display result)
780    (analyse-solo12 0)
781    ;; (display result)
782    (set! result (map
783                  ;; forced-configuration overrides, if it is set
784                  (lambda (x) (cons (moment x) (or (forced-configuration x) (configuration x))))
785                  (vector->list result)))
786    (if #f ;; pc-debug
787        (display result))
788    result))
789
790(define-public default-part-combine-mark-state-machine
791  ;; (current-state . ((split-state-event .
792  ;;                      (output-voice output-event next-state)) ...))
793  '((Initial . ((solo1   . (solo   SoloOneEvent Solo1))
794                (solo2   . (solo   SoloTwoEvent Solo2))
795                (unisono . (shared UnisonoEvent Unisono))))
796    (Solo1   . ((apart   . (#f     #f           Initial))
797                (chords  . (#f     #f           Initial))
798                (solo2   . (solo   SoloTwoEvent Solo2))
799                (unisono . (shared UnisonoEvent Unisono))))
800    (Solo2   . ((apart   . (#f     #f           Initial))
801                (chords  . (#f     #f           Initial))
802                (solo1   . (solo   SoloOneEvent Solo1))
803                (unisono . (shared UnisonoEvent Unisono))))
804    (Unisono . ((apart   . (#f     #f           Initial))
805                (chords  . (#f     #f           Initial))
806                (solo1   . (solo   SoloOneEvent Solo1))
807                (solo2   . (solo   SoloTwoEvent Solo2))))))
808
809(define-public (make-part-combine-marks state-machine split-list)
810  "Generate a sequence of part combiner events from a split list."
811
812  (define (get-state state-name)
813    (assq-ref state-machine state-name))
814
815  (let ((full-seq '()) ; sequence of { \context Voice = "x" {} ... }
816        (segment '()) ; sequence within \context Voice = "x" {...}
817        (prev-moment ZERO-MOMENT)
818        (prev-voice #f)
819        (state (get-state 'Initial)))
820
821    (define (commit-segment)
822      "Add the current segment to the full sequence and begin another."
823      (if (pair? segment)
824          (set! full-seq
825                (cons (make-music 'ContextSpeccedMusic
826                                  'context-id (symbol->string prev-voice)
827                                  'context-type 'Voice
828                                  'element (make-sequential-music (reverse! segment)))
829                      full-seq)))
830      (set! segment '()))
831
832    (define (handle-split split)
833      (let* ((moment (car split))
834             (action (assq-ref state (cdr split))))
835        (if action
836            (let ((voice (car action))
837                  (part-combine-event (cadr action))
838                  (next-state-name (caddr action)))
839              (if part-combine-event
840                  (let ((dur (ly:moment-sub moment prev-moment)))
841                    ;; start a new segment when the voice changes
842                    (if (not (eq? voice prev-voice))
843                        (begin
844                          (commit-segment)
845                          (set! prev-voice voice)))
846                    (if (not (equal? dur ZERO-MOMENT))
847                        (set! segment (cons (make-music 'SkipEvent
848                                                        'duration (make-duration-of-length dur)) segment)))
849                    (set! segment (cons (make-music part-combine-event) segment))
850
851                    (set! prev-moment moment)))
852              (set! state (get-state next-state-name))))))
853
854    (for-each handle-split split-list)
855    (commit-segment)
856    (make-sequential-music (reverse! full-seq))))
857
858(define-public default-part-combine-context-change-state-machine-one
859  ;; (current-state . ((split-state-event . (output-voice next-state)) ...))
860  '((Initial . ((apart         . (one    . Initial))
861                (apart-silence . (one    . Initial))
862                (apart-spanner . (one    . Initial))
863                (chords        . (shared . Initial))
864                (silence1      . (shared . Initial))
865                (silence2      . (null   . Demoted))
866                (solo1         . (solo   . Initial))
867                (solo2         . (null   . Demoted))
868                (unisono       . (shared . Initial))
869                (unisilence    . (shared . Initial))))
870
871    ;; After a part has been used as the exclusive input for a
872    ;; passage, we want to use it by default for unisono/unisilence
873    ;; passages because Part_combine_iterator might have killed
874    ;; multi-measure rests in the other part.  Here we call such a
875    ;; part "promoted".  Part one begins promoted.
876    (Demoted . ((apart         . (one    . Demoted))
877                (apart-silence . (one    . Demoted))
878                (apart-spanner . (one    . Demoted))
879                (chords        . (shared . Demoted))
880                (silence1      . (shared . Initial))
881                (silence2      . (null   . Demoted))
882                (solo1         . (solo   . Initial))
883                (solo2         . (null   . Demoted))
884                (unisono       . (null   . Demoted))
885                (unisilence    . (null   . Demoted))))))
886
887(define-public default-part-combine-context-change-state-machine-two
888  ;; (current-state . ((split-state-event . (output-voice next-state)) ...))
889  '((Initial . ((apart         . (two    . Initial))
890                (apart-silence . (two    . Initial))
891                (apart-spanner . (two    . Initial))
892                (chords        . (shared . Initial))
893                (silence1      . (null   . Initial))
894                (silence2      . (shared . Promoted))
895                (solo1         . (null   . Initial))
896                (solo2         . (solo   . Promoted))
897                (unisono       . (null   . Initial))
898                (unisilence    . (null   . Initial))))
899
900    ;; See the part-one state machine for the meaning of "promoted".
901    (Promoted . ((apart         . (two    . Promoted))
902                 (apart-silence . (two    . Promoted))
903                 (apart-spanner . (two    . Promoted))
904                 (chords        . (shared . Promoted))
905                 (silence1      . (null   . Initial))
906                 (silence2      . (shared . Promoted))
907                 (solo1         . (null   . Initial))
908                 (solo2         . (solo   . Promoted))
909                 (unisono       . (shared . Promoted))
910                 (unisilence    . (shared . Promoted))))))
911
912(define-public (make-part-combine-context-changes state-machine split-list)
913  "Generate a sequence of part combiner context changes from a split list."
914
915  (define (get-state state-name)
916    (assq-ref state-machine state-name))
917
918  (let* ((change-list '())
919         (prev-moment
920          ;; the start moment is in the first entry of the split list
921          (if (and (pair? split-list) (pair? (car split-list)))
922              (caar split-list)
923              ZERO-MOMENT))
924         (prev-change-moment prev-moment)
925         (prev-voice #f)
926         (state (get-state 'Initial)))
927
928    (define (handle-split split)
929      (let* ((moment (car split))
930             (action (assq-ref state (cdr split))))
931        (if action
932            (let ((voice (car action))
933                  (next-state-name (cdr action)))
934              (if (not (eq? voice prev-voice))
935                  (begin
936                    (set! change-list
937                          (cons (skip-of-moment-span prev-change-moment moment)
938                                change-list))
939                    (set! change-list
940                          (cons (make-music
941                                 'ContextChange
942                                 'change-tag '$partCombine
943                                 'change-to-type 'Voice
944                                 'change-to-id (symbol->string voice))
945                                change-list))
946                    (set! prev-change-moment moment)
947                    (set! prev-voice voice)))
948              (set! prev-moment moment)
949              (set! state (get-state next-state-name))))))
950
951    ;; (display split-list)
952    (for-each handle-split split-list)
953    ;; add a final skip so that the length of the music is correct
954    (set! change-list (cons (skip-of-moment-span prev-change-moment prev-moment)
955                            change-list))
956    (let ((result (make-sequential-music (reverse! change-list))))
957      ;; (display-lily-music result)
958      result)))
959
960;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
961
962(define-public (add-quotable name mus)
963  (let* ((tab (eval 'musicQuotes (current-module)))
964         (voicename (get-next-unique-voice-name))
965         ;; recording-group-emulate returns an assoc list (reversed!), so
966         ;; hand it a proper unique context name and extract that key:
967         (ctx-spec (context-spec-music mus 'Voice voicename))
968         (listener (ly:parser-lookup 'partCombineListener))
969         (context-list (reverse (recording-group-emulate ctx-spec listener)))
970         (raw-voice (assoc voicename context-list))
971         (quote-contents (and raw-voice (reverse! (cdr raw-voice)))))
972
973    (define (has-events? e)
974      (and (pair? e)
975           (pair? (car e))
976           (pair? (cdar e))))
977
978    ;; If the context-specced quoted music does not contain anything, try to
979    ;; use the first child, i.e. the next in context-list after voicename
980    ;; That's the case e.g. for \addQuote "x" \relative c \new Voice {...}
981    ;;
982    ;; Note that if raw-voice is #f, so is quote-contents, in which
983    ;; case the following loop is skipped.
984    (if (not (has-events? quote-contents))
985        (let find-non-empty ((current-tail (member raw-voice context-list)))
986          ;; if voice has contents, use them, otherwise check next ctx
987          (if (null? current-tail)
988              #f
989              (let ((candidate (and (pair? (car current-tail))
990                                    (pair? (cdar current-tail))
991                                    (reverse! (cdar current-tail)))))
992                (if (has-events? candidate)
993                    (set! quote-contents candidate)
994                    (find-non-empty (cdr current-tail)))))))
995
996    (if (has-events? quote-contents)
997        (hash-set! tab name (list->vector quote-contents))
998        (ly:music-warning mus (_ "quoted music `~a' is empty") name))))
999