Save track files in new Sound model:

* Consolidate migrations
* Add Sound model. Each sound can belong to a track and contains
  informations about one sound file.

app/controllers/sounds_controller.rb

@@ -0,0 +1,6 @@
+class SoundsController < ApplicationController
+  def show
+    sound = Sound.find params[:id]
+    send_file sound.path, :type => sound.mime_type
+  end
+end

app/controllers/tracks_controller.rb

@@ -8,19 +8,11 @@ class TracksController < ApplicationController
   end
 
   def create
-    @track = Track.new(:name => params[:track][:name])
-    if @track.save_with_file(
-        params[:track][:file],
-        params[:track][:file].content_type
-      )
+    @track = Track.new params[:track]
+    if @track.save
       redirect_to @track
     else
       render :new
     end
   end
-
-  def download
-    track = Track.find params[:id]
-    send_file track.filepath, :type => track.mime_type
-  end
 end

app/models/sound.rb

@@ -0,0 +1,18 @@
+require 'fileutils'
+
+class Sound < ActiveRecord::Base
+  belongs_to :track
+
+  validates_presence_of :sha256
+  validates_presence_of :mime_type
+
+  def path
+    "#{Rails.root}/data/sounds/#{sha256}"
+  end
+
+  def file=(file)
+    self.sha256 = Digest::SHA256.file(file.path).hexdigest
+    FileUtils.cp file.path, path
+    self.mime_type = file.content_type
+  end
+end

app/models/track.rb

@@ -1,19 +1,20 @@
 class Track < ActiveRecord::Base
-  validates_presence_of :name
-  validates_presence_of :mime_type
-  validates_presence_of :sha256
+  has_many :sounds
 
-  def filepath
-   "#{Rails.root}/data/tracks/#{sha256}"
+  attr_accessible :name, :file
+
+  validates_presence_of :name
+
+  def file=(file)
+    sounds.build({:file => file})
   end
 
-  def save_with_file(file, mime_type)
-    self.sha256 = Digest::SHA256.file(file.path).hexdigest
-    self.mime_type = mime_type
-    File.open(filepath, 'w') do |f|
-      f.write file.read
-    end
-    save!
+  def sound
+    sounds.first
+  end
+
+  def sound?
+    sounds.any?
   end
 
   def self.latest

app/views/tracks/show.html.haml

@@ -1,3 +1,4 @@
 %h1= @track.name
-%audio{:src => download_track_path(@track), :controls => true, :autoplay => true}
-  Your browser does not support the audio element
+- if @track.sound?
+  %audio{:src => sound_path(@track.sound), :controls => true, :autoplay => true}
+    Your browser does not support the audio element