Data commit

Task/Morse-code/CoffeeScript/morse-code.coffee

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+class Morse
+  constructor : (@unit=0.05, @freq=700) ->
+
+    @cont = new AudioContext()
+    @time = @cont.currentTime
+    @alfabet = "..etianmsurwdkgohvf.l.pjbxcyzq..54.3...2.......16.......7...8.90"
+
+  getCode : (letter) ->
+    i = @alfabet.indexOf letter
+    result = ""
+    while i > 1
+      result = ".-"[i%2] + result
+      i //= 2
+    result
+
+  makecode : (data) ->
+    for letter in data
+      code = @getCode letter
+      if code != undefined then @maketime code else @time += @unit * 7
+
+  maketime : (data) ->
+    for timedata in data
+      timedata = @unit * ' . _'.indexOf timedata
+      if timedata > 0
+        @maketone timedata
+        @time += timedata
+        @time += @unit * 1
+    @time += @unit * 2
+
+  maketone : (data) ->
+    start = @time
+    stop = @time + data
+    @gain.gain.linearRampToValueAtTime 0, start
+    @gain.gain.linearRampToValueAtTime 1, start + @unit / 8
+    @gain.gain.linearRampToValueAtTime 1, stop - @unit / 16
+    @gain.gain.linearRampToValueAtTime 0, stop
+
+  send : (text) ->
+    osci = @cont.createOscillator()
+    osci.frequency.value = @freq
+    @gain = @cont.createGain()
+    @gain.gain.value = 0
+    osci.connect @gain
+    @gain.connect @cont.destination
+
+    osci.start @time
+    @makecode text
+    @cont
+
+morse = new Morse()
+morse.send 'hello world 0123456789'