-
Notifications
You must be signed in to change notification settings - Fork 0
/
event.cljc
520 lines (469 loc) · 18.7 KB
/
event.cljc
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
(ns mayu.frp.impl.event
(:require [allpa.core :as a
:refer [curry defprotomethod]]
[mayu.async
:refer [go go-loop timeout <! chan >! close!]]
[wayra.monoid
:refer [Monoid mappend maplus mempty]]
#?(:clj [clojure.core :as core]
:cljs [cljs.core :as core])
#?(:clj [clojure.pprint :refer [pprint]]
:cljs [cljs.pprint :refer [pprint]])))
; TODO throw error on recursive def. will cause problems but def needed
(defrecord Push [val src count])
(defrecord Src [src count])
(defrecord Deps [deps])
(def global-push-counts (atom {}))
(defn global-count [id]
(get @global-push-counts id 0))
(defn init-dep-counts [deps]
(reduce #(assoc %1 %2 (global-count %2)) {} deps))
(defrecord RawEvent [state])
(def next-event-id (atom 1))
(def never (->RawEvent (atom {:id 0 :on? true})))
(defn never? [e] (= 0 (:id @(:state e))))
(defn Event
([] (Event (fn [_] (fn [])) nil))
([on-required] (Event on-required nil))
([on-required get-deps]
(let [id @next-event-id]
(swap! next-event-id inc)
(->RawEvent (atom {:id id
:subs {}
:next-sub-id 1
:on-required on-required
:off-callback (fn [])
:source? (nil? get-deps)
:get-deps (or get-deps #(-> [id]))
:deps []
:pushes 1
:on? false
:num-awaiting 0
:awaiting-on (chan)})))))
(defprotomethod push? [_] Push true [Src Deps] false)
(defprotomethod deps? [_] Deps true [Push Src] false)
(defn send! [e msg]
(when (not (never? e))
(let [{:keys [state]} e
{:keys [subs on? num-awaiting awaiting-on deps id pushes]} @state
{new-deps :deps :keys [src count]} msg
original-src src
src (if (= original-src ::self) id src)
count (if (= original-src ::self) (inc pushes) count)
msg (if (= original-src ::self)
(merge msg {:src src :count count})
msg)]
(when (= original-src ::self)
(when (global-count id)
(swap! global-push-counts (curry assoc id (inc pushes))))
(swap! state (curry assoc :pushes (inc pushes))))
(if on?
(when (or (and (not (deps? msg))
(= count (global-count src))
(or (not= src ::none)
(push? msg)))
(and (deps? msg)
(not= deps new-deps)))
(when (deps? msg)
(swap! state #(assoc %1 :deps new-deps)))
(doseq [on (vals subs)]
(on msg)))
(do (swap! state #(update %1 :num-awaiting inc))
(go (>! awaiting-on {:msg msg :order num-awaiting})))))))
(defn on! [e]
(let [{:keys [state]} e
{:keys [on? awaiting-on num-awaiting]} @state]
(when (and (not (never? e)) (not on?))
(swap! state (curry assoc :on? true))
(go-loop [left num-awaiting
msgs {}]
(if (> left 0)
(let [{:keys [msg order]} (<! awaiting-on)]
(recur (dec left) (assoc msgs order msg)))
(do
(close! awaiting-on)
(doseq [id (range (count msgs))]
(send! e (get msgs id)))))))
e))
(defn off! [e]
(when (not (never? e))
(let [{:keys [state]} e]
(swap! state (curry merge {:id 0 :subs nil :awaiting-on nil})))))
(defn push! [e val]
(let [{:keys [state]} e
{:keys [id pushes source?]} @state
new-pushes (inc pushes)]
(when (not source?)
(throw (a/Err "Can only push to source event types")))
(when (global-count id)
(swap! global-push-counts (curry assoc id new-pushes)))
(swap! state (curry assoc :pushes new-pushes))
(send! e (->Push val id new-pushes))))
(defn subscribe! [e on]
(if (never? e)
(fn [])
(let [{:keys [state]} e
{:keys [next-sub-id on-required get-deps id pushes]} @state
sub-count (fn [] (count (:subs @state)))]
(swap! state #(-> %1
(assoc :next-sub-id (inc next-sub-id))
(assoc-in [:subs next-sub-id] on)))
(when (= 1 (sub-count))
(swap! global-push-counts #(assoc %1 id pushes))
(swap! state (curry assoc :off-callback (on-required #(send! e %1))))
(swap! state (curry assoc :deps (get-deps))))
(fn []
(swap! state (curry update :subs #(dissoc %1 next-sub-id)))
(when (= 0 (sub-count))
(swap! global-push-counts #(dissoc %1 id))
((:off-callback @state)))))))
(defn consume! [e on] (subscribe! e (fn [msg]
(when (push? msg) (on (:val msg))))))
(defn shadow [e]
(if (never? e)
never
(on! (Event
#(subscribe! e (fn [msg]
(when (push? msg)
(% (merge msg {:src ::none :count 0})))))
#(-> [])))))
(defn map [f e]
(if (never? e)
never
(on! (Event
#(subscribe! e (fn [msg]
(% (if (push? msg)
(update msg :val f)
msg))))
#(:deps @(:state e))))))
(defn reduce [r i e]
(if (never? e)
never
(let [a-acc (atom i)]
(on! (Event
#(subscribe! e (fn [{:keys [val] :as msg}]
(if (push? msg)
(do (swap! a-acc (fn [acc] (r acc val)))
(% (assoc msg :val @a-acc)))
(% msg))))
#(:deps @(:state e)))))))
(defn filter [p e]
(if (never? e)
never
(on! (Event
#(subscribe! e
(fn [{:keys [val src count] :as msg}]
(cond (and (push? msg)
(not (p val))) (% (->Src src count))
:else (% msg))))
#(:deps @(:state e))))))
(defn remove [p e]
(filter (comp not p) e))
(defn join-to-deps [dep-data]
(->> @dep-data vals (core/reduce merge {}) keys))
(defprotomethod on-join-message [msg dep-data stashes send-self! e]
Deps
(let [{:keys [deps]} msg
{:keys [id]} @(:state e)
dep-counts (init-dep-counts deps)]
(doseq [[src count] dep-counts]
(let [stashed (get-in @stashes [src count])]
(when (and (not (empty? stashed))
(->> @dep-data
vals
(every? #(= (get %1 src count) count))))
(swap! stashes #(dissoc %1 src))
(core/reduce #(%2 %1) false stashed))))
(swap! dep-data #(assoc %1 id dep-counts))
(send-self! (->Deps (join-to-deps dep-data))))
[Push Src]
(let [{:keys [val src count]} msg
{:keys [id]} @(:state e)]
(if (= ::none src)
(send-self! (assoc msg :val {:val val :sent-sibling? false}))
(let [sendable? (->> (dissoc @dep-data id)
vals
(every? #(= (get %1 src count) count)))
stashed (get-in @stashes [src count])]
(swap! dep-data #(assoc-in %1 [id src] count))
(cond
sendable?
(do (swap! stashes #(dissoc %1 src))
(when (or (empty? stashed)
(push? msg))
(send-self! (merge msg {:val {:sent-sibling? false
:val val}})))
(core/reduce #(%2 %1) (push? msg) stashed))
(push? msg)
(let [send! #(do (send-self! (merge msg {:val {:sent-sibling? %1
:val val}}))
true)]
(swap! stashes #(update-in %1 [src count] (curry conj send!)))))))))
(defn raw-join [& arg-events]
(let [events (core/remove never? arg-events)
on-required
(fn [events dep-data stashes send-self!]
(let [offs
(-> #(subscribe! %1 (curry on-join-message
dep-data
stashes
send-self!
%1))
(core/map events)
vec)]
(fn []
(reset! dep-data {})
(reset! stashes {})
(doseq [off offs] (off)))))
perform-join
(fn [events]
(let [stashes (atom {})
dep-data (atom {})]
(on! (Event #(on-required events dep-data stashes %1)
(fn []
(reset! dep-data
(core/reduce #(let [{:keys [id deps]}
@(:state %2)]
(assoc %1 id
(init-dep-counts deps)))
{}
events))
(join-to-deps dep-data))))))]
(case (count events)
0 never
1 (map #(-> {:val %1 :sent-sibling? false}) (first events))
(perform-join events))))
(defn join [& events] (map :val (apply raw-join events)))
(defn join-skip-siblings [& events]
(->> (apply raw-join events)
(filter (comp not :sent-sibling?))
(map :val)))
(defn flat-map [f e]
(if (never? e)
never
(let [curr-off (atom (fn []))
full-off (atom (fn []))
{:keys [id]} @(:state e)
inner-deps (atom {})
outer-deps (atom {})
inner-stashes (atom {})
outer-stashes (atom {})
to-deps
(fn [] (->> (merge @inner-deps @outer-deps)
keys))
process-inner
(fn [send-self! {:keys [val src count deps] :as msg}]
(cond
(= ::none src)
(send-self! msg)
(deps? msg)
(do (reset! inner-deps (init-dep-counts deps))
(send-self! (->Deps (to-deps)))
(doseq [[_ stashes] @outer-stashes]
((get stashes (apply max (keys stashes)))))
(reset! outer-stashes {}))
:else
(do (swap! inner-deps #(assoc %1 src count))
(cond
(= (get @outer-deps src count) count)
(let [stashed (get-in @outer-stashes [src count])]
(when (or (push? msg)
(empty? stashed))
(send-self! msg))
(doseq [send! stashed]
(send!))
(swap! outer-stashes #(dissoc %1 src)))
(push? msg)
(swap! inner-stashes
(curry update-in [src count]
#(conj %1 (fn [] (send-self! msg)))))))))
process-outer
(fn [send-self! {:keys [val src count deps] :as msg}]
(cond
(push? msg)
(let [e-next (f val)
send!
(fn []
(@curr-off)
(reset! curr-off
(subscribe! e-next #(process-inner send-self! %1)))
(reset! inner-deps
(init-dep-counts (:deps @(:state e-next))))
(when (empty? (get-in @inner-stashes [src count]))
(send-self! (->Src src count)))
(send-self! (->Deps (to-deps)))
(doseq [[_ stashes] @outer-stashes]
((get stashes (apply max (keys stashes)))))
(reset! outer-stashes {}))]
(when-not (= ::none src)
(swap! outer-deps #(assoc %1 src count)))
(cond
(= (get @inner-deps src count) count)
(let [stashed (get-in @inner-stashes [src count])]
(send!)
(doseq [send! stashed]
(send!))
(swap! inner-stashes #(dissoc %1 src)))
:else
(swap! outer-stashes
(curry update-in [src count]
#(conj %1 send!)))))
(deps? msg)
(do (reset! outer-deps (init-dep-counts deps))
(send-self! (->Deps (to-deps)))
(doseq [[_ stashes] @inner-stashes]
((get stashes (apply max (keys stashes)))))
(reset! inner-stashes {}))
:else
(when-not (= ::none src)
(swap! outer-deps #(assoc %1 src count))
(let [stashed (get-in @inner-stashes [src count])]
(when (= (get @inner-deps src count) count)
(swap! inner-stashes #(dissoc %1 src))
(when (empty? stashed)
(send-self! msg))
(doseq [send! stashed]
(send!)))))))]
(on! (Event
(fn [send-self!]
(reset! full-off (subscribe! e #(process-outer send-self! %1)))
(fn []
(@curr-off)
(@full-off)
(reset! inner-deps {})
(reset! outer-deps {})
(reset! inner-stashes {})
(reset! inner-stashes {})
(reset! curr-off (fn []))
(reset! full-off (fn []))))
(fn []
(reset! outer-deps (init-dep-counts (:deps @(:state e))))
(to-deps)))))))
(defn flatten [ee] (flat-map identity ee))
(defn on-preempted [init-id send-self!]
(fn [msg]
(when (= init-id (get msg :src))
(throw (a/Err "Resursive Event Encountered")))
(send-self! msg)))
(defn preempt
([f] (preempt identity f))
([from-res f]
(let [e-channel (chan)
off-channel (chan)
e-init (Event (fn [send-self!]
(go (let [{:keys [e quick-off init-id]} (<! e-channel)
off (subscribe! e (on-preempted init-id
send-self!))]
(on! e)
(quick-off)
(>! off-channel off)))
(fn [] (go ((<! off-channel)))))
#(-> []))
res (f e-init)
e (from-res res)
;; TODO this is a hack but Im not sure why its needed
quick-off (consume! e (fn [_]))]
(on! e-init)
(swap! (:state e) #(merge %1 {:awaiting-on (chan) :on? false}))
(go (>! e-channel {:e e :quick-off quick-off
:init-id (:id @(:state e-init))}))
res)))
(defn defer-off
([e] (defer-off e 0))
([e ms]
(if (never? e)
never
(let [soft-on? (atom false)
on? (atom false)
off-fn (atom (fn []))]
(on! (Event (fn [send-self!]
(reset! soft-on? true)
(when (not @on?)
(reset! off-fn (subscribe! e send-self!))
(reset! on? true))
(fn []
(reset! soft-on? false)
(go (<! (timeout ms))
(when (not @soft-on?)
(reset! on? false)
(@off-fn)
(reset! off-fn (fn []))))))
#(:deps @(:state e))))))))
(defn throttle [e ms]
(let [sender (atom (fn [_]))
send! (fn [{:keys [val]}] (@sender (->Push val ::none 0)))
throttling (atom false)
queued (atom [])]
(on!
(Event (fn [send-self!]
(reset! sender send-self!)
(let [off
(subscribe! e
(fn [msg]
(when (push? msg)
(if @throttling
(reset! queued [msg])
(do (reset! throttling true)
(send! msg)
(go-loop []
(<! (timeout ms))
(if (> (count @queued) 0)
(do (send! (first @queued))
(reset! queued [])
(recur))
(reset! throttling false))))))))]
(fn [] (off) (reset! sender (fn [_])))))
#(-> [])))))
(defn defer [e ms]
(let [sender (atom (fn [_]))
send! (fn [{:keys [val]}] (@sender (->Push val ::none 0)))]
(on!
(Event (fn [send-self!]
(reset! sender send-self!)
(let [off
(subscribe! e
(fn [msg]
(when (push? msg)
(go (<! (timeout ms))
(send! msg)))))]
(fn [] (off) (reset! sender (fn [_])))))
#(-> [])))))
(defn timer [ms]
(let [c (chan 1)]
(on! (Event #(do (go (>! c :on))
(go-loop []
(let [msg (<! c)]
(when (not= :off msg)
(%1 (->Push :on ::none 0))
(<! (timeout ms))
(>! c :on)
(recur))))
(fn [] (go (>! c :off))))
#(-> [])))))
(defn dedup [e]
(let [set? (atom false)
last (atom nil)]
(if (never? e)
never
(on! (Event
#(let [off (subscribe! e
(fn [{:keys [val src count] :as msg}]
(cond (push? msg)
(let [was? @set?
curr @last]
(reset! set? true)
(reset! last val)
(if (or (not was?)
(not= curr val))
(% msg)
(% (->Src src count))))
:else (% msg))))]
(fn []
(reset! set? false)
(off)))
#(:deps @(:state e)))))))
(extend-protocol Monoid
RawEvent
(mappend [e1 e2] (join e1 e2))
(maplus [e1 e2] (join e1 e2))
(mempty [_] never))