[Closes #515] Refactor sound resources to address inconsistent behaviors

src/engine/Engine.ts

@@ -17,7 +17,6 @@
 /// <reference path="Particles.ts" />
 /// <reference path="Drawing/Animation.ts" />
 /// <reference path="Camera.ts" />
-/// <reference path="Sound.ts" />
 /// <reference path="Loader.ts" />
 /// <reference path="Promises.ts" />
 /// <reference path="Util/Util.ts" />

src/engine/Interfaces/IAudio.ts

@@ -0,0 +1,12 @@
+/// <reference path="../Promises.ts" />
+
+module ex {
+   export interface IAudio {
+      setVolume(volume: number);
+      setLoop(loop: boolean);
+      isPlaying(): boolean;
+      play(): ex.Promise<any>;
+      pause();
+      stop();
+   }
+}

src/engine/Interfaces/IAudioImplementation.ts

@@ -0,0 +1,23 @@
+module ex {
+
+   /**
+    * Represents an audio implementation like [[AudioTag]] or [[WebAudio]]
+    */
+   export interface IAudioImplementation {
+
+      /**
+       * XHR response type
+       */
+      responseType: string;
+
+      /**
+       * Processes raw data and transforms into sound data
+       */
+      processData(data: Blob|ArrayBuffer): ex.Promise<string|AudioBuffer>;
+
+      /**
+       * Factory method that returns an instance of a played audio track
+       */
+      createInstance(data: string|AudioBuffer): IAudio;
+   }
+}

src/engine/Interfaces/ILoadable.ts

@@ -21,7 +21,14 @@ module ex {
        */
       load(): Promise<any>;
 
+      /**
+       * Gets the data that was loaded
+       */
       getData(): any;
+
+      /**
+       * Sets the data (can be populated from remote request or in-memory data)
+       */
       setData(data: any): void;
 
       /**
@@ -34,7 +41,6 @@ module ex {
        */
       wireEngine(engine: Engine): void;
 
-
       /**
        * onprogress handler
        */

src/engine/Loader.ts

@@ -2,6 +2,7 @@
 /// <reference path="Util/DrawUtil.ts" />
 /// <reference path="Promises.ts" />
 /// <reference path="Resources/Resource.ts" />
+/// <reference path="Resources/Sound.ts" />
 /// <reference path="Interfaces/ILoadable.ts" />
 /// <reference path="Interfaces/ILoader.ts" />
 
@@ -339,7 +340,7 @@ module ex {
          }
 
          // unlock Safari WebAudio context
-         Internal.WebAudio.unlock();
+         WebAudio.unlock();
 
          // continue to play game
          this._waitPromise.resolve(this._loadedValue);