; Beat-synced video recipe with lambda reducer
(recipe "beat-sync-lambda"
  :version "1.0"
  :encoding (:codec "libx264" :crf 22 :preset "fast" :audio-codec "aac")

  ; Declare analyzers and effects
  (analyzer beats :path "../artdag-analyzers/beats/analyzer.py")
  (effect invert :path "../artdag-effects/invert/effect.py")

  ; Sources
  (def video (source :path "new.webm" :description "Video input"))
  (def audio (-> (source :path "dizzy.mp3" :description "Audio input")
                 (segment :start 0 :duration 10)))

  ; Analyze audio for beats
  (def analysis (-> audio (analyze beats)))

  ; Slice video at beat times using lambda reducer
  (def synced-video (slice-on video analysis
                      :times times
                      :init 0
                      :fn (fn [acc i start end]
                            {:source video
                             :effects (if (odd? i) (list invert) (list))
                             :acc (inc acc)})))

  ; Mux video with audio
  (mux synced-video audio))