From 22dba358b8c9cfa278d5a98bc03a5e9d07a7cfeb Mon Sep 17 00:00:00 2001
From: Spencer Russell <spencer.f.russell@gmail.com>
Date: Mon, 13 Jan 2014 19:19:56 -0500
Subject: [PATCH] adds ability to wait for an AudioNode

---
 src/AudioIO.jl | 23 +++++++++++++++++++++--
 src/nodes.jl   | 25 ++++++++++++++-----------
 src/sndfile.jl | 11 ++++++-----
 3 files changed, 41 insertions(+), 18 deletions(-)

diff --git a/src/AudioIO.jl b/src/AudioIO.jl
index a786d12..a9ee241 100644
--- a/src/AudioIO.jl
+++ b/src/AudioIO.jl
@@ -33,7 +33,7 @@ include("sndfile.jl")
 
 # Play an AudioNode by adding it as an input to the root mixer node
 function play(node::AudioNode, stream::AudioStream)
-    node.active = true
+    activate(node)
     add_input(stream.mixer, node)
     return node
 end
@@ -76,8 +76,27 @@ function play{T <: Unsigned}(arr::Array{T}, args...)
 end
 
 function stop(node::AudioNode)
+    deactivate(node)
+    node
+end
+
+function activate(node::AudioNode)
+    node.active = true
+end
+
+function deactivate(node::AudioNode)
     node.active = false
-    return node
+    notify(node.deactivate_cond)
+end
+
+function is_active(node::AudioNode)
+    node.active
+end
+
+function Base.wait(node::AudioNode)
+    if is_active(node)
+        wait(node.deactivate_cond)
+    end
 end
 
 end # module AudioIO
diff --git a/src/nodes.jl b/src/nodes.jl
index 2f98f97..ce2cb62 100644
--- a/src/nodes.jl
+++ b/src/nodes.jl
@@ -6,11 +6,12 @@ export SinOsc, AudioMixer, ArrayPlayer, AudioInput
 
 type SinOsc <: AudioNode
     active::Bool
+    deactivate_cond::Condition
     freq::Real
     phase::FloatingPoint
 
     function SinOsc(freq::Real)
-        new(false, freq, 0.0)
+        new(false, Condition(), freq, 0.0)
     end
 end
 
@@ -18,7 +19,7 @@ function render(node::SinOsc, device_input::AudioBuf, info::DeviceInfo)
     phase = AudioSample[1:info.buf_size] * 2pi * node.freq / info.sample_rate
     phase += node.phase
     node.phase = phase[end]
-    return sin(phase), node.active
+    return sin(phase), is_active(node)
 end
 
 #### AudioMixer ####
@@ -31,6 +32,7 @@ const MAX_MIXER_INPUTS = 32
 
 type AudioMixer <: AudioNode
     active::Bool
+    deactivate_cond::Condition
     mix_inputs::Array{MaybeAudioNode}
 
     function AudioMixer{T <: AudioNode}(mix_inputs::Array{T})
@@ -39,7 +41,7 @@ type AudioMixer <: AudioNode
         for (i, node) in enumerate(mix_inputs)
             input_array[i] = node
         end
-        new(false, input_array)
+        new(false, Condition(), input_array)
     end
 
     function AudioMixer()
@@ -87,7 +89,7 @@ function render(node::AudioMixer, device_input::AudioBuf, info::DeviceInfo)
             end
         end
     end
-    return mix_buffer, node.active
+    return mix_buffer, is_active(node)
 end
 
 #### Array Player ####
@@ -96,11 +98,12 @@ end
 
 type ArrayPlayer <: AudioNode
     active::Bool
+    deactivate_cond::Condition
     arr::AudioBuf
     arr_index::Int
 
     function ArrayPlayer(arr::AudioBuf)
-        new(false, arr, 1)
+        new(false, Condition(), arr, 1)
     end
 end
 
@@ -111,13 +114,12 @@ function render(node::ArrayPlayer, device_input::AudioBuf, info::DeviceInfo)
     range_end = min(i + info.buf_size-1, length(node.arr))
     output = node.arr[i:range_end]
     if length(output) < info.buf_size
-        # we're finished with the array, pad with zeros and clear our active
-        # flag
+        # we're finished with the array, pad with zeros and deactivate
         output = vcat(output, zeros(AudioSample, info.buf_size - length(output)))
-        node.active = false
+        deactivate(node)
     end
     node.arr_index = range_end + 1
-    return output, node.active
+    return output, is_active(node)
 end
 
 #### AudioInput ####
@@ -126,14 +128,15 @@ end
 
 type AudioInput <: AudioNode
     active::Bool
+    deactivate_cond::Condition
     channel::Int
 
     function AudioInput(channel::Int)
-        new(false, channel)
+        new(false, Condition(), channel)
     end
 end
 
 function render(node::AudioInput, device_input::AudioBuf, info::DeviceInfo)
     @assert size(device_input, 1) == info.buf_size
-    return device_input[:, node.channel], node.active
+    return device_input[:, node.channel], is_active(node)
 end
diff --git a/src/sndfile.jl b/src/sndfile.jl
index bf557be..130023d 100644
--- a/src/sndfile.jl
+++ b/src/sndfile.jl
@@ -91,10 +91,11 @@ end
 
 type FilePlayer <: AudioNode
     active::Bool
+    deactivate_cond::Condition
     file::AudioFile
 
     function FilePlayer(file::AudioFile)
-        node = new(false, file)
+        node = new(false, Condition(), file)
         finalizer(node, node -> close(node.file))
         return node
     end
@@ -110,16 +111,16 @@ function render(node::FilePlayer, device_input::AudioBuf, info::DeviceInfo)
     audio = read(node.file, info.buf_size, AudioSample)
 
     if audio == Nothing
-        node.active = false
-        return zeros(AudioSample, info.buf_size), node.active
+        deactivate(node)
+        return zeros(AudioSample, info.buf_size), is_active(node)
     end
 
     # if the file is stereo, mix the two channels together
     if node.file.sfinfo.channels == 2
-        return (audio[1, :] / 2) + (audio[2, :] / 2), node.active
+        return (audio[1, :] / 2) + (audio[2, :] / 2), is_active(node)
     end
 
-    return audio, node.active
+    return audio, is_active(node)
 end
 
 function play(filename::String, args...)