Experimenting with optimal event attachment strategy.

common/lib/xmodule/xmodule/js/src/videoalpha/display.coffee

@@ -83,6 +83,19 @@ class @VideoAlpha
   embed: ->
     @player = new VideoPlayerAlpha video: this
 
+    @attachEventDispatchToFunctions
+      onPlay: 'play_video'
+      onPause: 'pause_video'
+
+  attachEventDispatchToFunctions: (funcList) ->
+    $.each funcList, (funcName, eventName) =>
+      @player[funcName] = @attachEventDispatch(@player[funcName], eventName)  if @player.hasOwnProperty(funcName)
+
+  attachEventDispatch: (func, eventName) ->
+    =>
+      @log eventName
+      func.apply this, arguments
+
   fetchMetadata: (url) ->
     @metadata = {}
     $.each @videos, (speed, url) =>
@@ -92,6 +105,15 @@ class @VideoAlpha
     @metadata[@youtubeId()].duration
 
   log: (eventName)->
+    console.log 'log'
+    console.log 'this = ', this
+    console.log
+      id: @id
+      code: @youtubeId()
+      currentTime: @player.currentTime
+      speed: @speed
+    console.log ''
+
     logInfo =
       id: @id
       code: @youtubeId()

common/lib/xmodule/xmodule/js/src/videoalpha/display/video_player.coffee

@@ -184,7 +184,6 @@ class @VideoPlayerAlpha extends SubviewAlpha
       @caption.pause()
 
   onPlay: =>
-    @video.log 'play_video'
     unless @player.interval
       @player.interval = setInterval(@update, 200)
     if @video.show_captions is true
@@ -193,7 +192,6 @@ class @VideoPlayerAlpha extends SubviewAlpha
     @progressSlider.play()
 
   onPause: =>
-    @video.log 'pause_video'
     clearInterval(@player.interval)
     @player.interval = null
     if @video.show_captions is true
@@ -206,6 +204,7 @@ class @VideoPlayerAlpha extends SubviewAlpha
       @caption.pause()
 
   onSeek: (event, time) =>
+    console.log 'old time = ' + @currentTime + ', new time = ' + time
     @player.seekTo(time, true)
     if @isPlaying()
       clearInterval(@player.interval)

common/lib/xmodule/xmodule/js/src/videoalpha/display/video_progress_slider.coffee

@@ -6,7 +6,11 @@ class @VideoProgressSliderAlpha extends SubviewAlpha
     @slider = @el.slider
       range: 'min'
       change: @onChange
-      slide: @onSlide
+
+      # We don't want to attach to 'slide' event because we already have 'change' event.
+      # If we have two events, then callback will be triggered twice, sending misinformation
+      # to the server.
+      # slide: @onSlide
       stop: @onStop
     @buildHandle()