Copy audio-related files into js/ instead of symlinking them (#1456)

This adds a new copy:deps task into the overall default task, and it
needs to be run before running the product for the first time, and after
upgrading audio-related deps.

FREEBIE

Gruntfile.js

@@ -126,6 +126,15 @@ module.exports = function(grunt) {
       ]
     },
     copy: {
+      deps: {
+        files: [{
+          src: 'components/mp3lameencoder/lib/Mp3LameEncoder.js',
+          dest: 'js/Mp3LameEncoder.min.js'
+        }, {
+          src: 'components/webaudiorecorder/lib/WebAudioRecorderMp3.js',
+          dest: 'js/WebAudioRecorderMp3.js'
+        }],
+      },
       res: {
         files: [{ expand: true, dest: 'dist/', src: ['<%= dist.res %>'] }],
       },
@@ -491,9 +500,9 @@ module.exports = function(grunt) {
   grunt.registerTask('tx', ['exec:tx-pull', 'locale-patch']);
   grunt.registerTask('dev', ['default', 'connect', 'watch']);
   grunt.registerTask('test', ['jshint', 'jscs', 'unit-tests']);
-  grunt.registerTask('copy_dist', ['gitinfo', 'copy']);
+  grunt.registerTask('copy_dist', ['gitinfo', 'copy:res', 'copy:src']);
   grunt.registerTask('date', ['gitinfo', 'getExpireTime']);
   grunt.registerTask('prep-release', ['gitinfo', 'clean-release', 'fetch-release']);
-  grunt.registerTask('default', ['concat', 'sass', 'date']);
+  grunt.registerTask('default', ['concat', 'copy:deps', 'sass', 'date']);
 
 };

js/Mp3LameEncoder.min.js

@@ -1 +0,0 @@
-../components/mp3lameencoder/lib/Mp3LameEncoder.js

js/WebAudioRecorderMp3.js

@@ -1 +0,0 @@
-../components/webaudiorecorder/lib/WebAudioRecorderMp3.js

js/WebAudioRecorderMp3.js

@@ -0,0 +1,91 @@
+importScripts("Mp3LameEncoder.min.js");
+
+var NUM_CH = 2, // constant
+    sampleRate = 44100,
+    options = undefined,
+    maxBuffers = undefined,
+    encoder = undefined,
+    recBuffers = undefined,
+    bufferCount = 0;
+
+function error(message) {
+  self.postMessage({ command: "error", message: "mp3: " + message });
+}
+
+function init(data) {
+  if (data.config.numChannels === NUM_CH) {
+    sampleRate = data.config.sampleRate;
+    options = data.options;
+  } else
+    error("numChannels must be " + NUM_CH);
+};
+
+function setOptions(opt) {
+  if (encoder || recBuffers)
+    error("cannot set options during recording");
+  else
+    options = opt;
+}
+
+function start(bufferSize) {
+  maxBuffers = Math.ceil(options.timeLimit * sampleRate / bufferSize);
+  if (options.encodeAfterRecord)
+    recBuffers = [];
+  else
+    encoder = new Mp3LameEncoder(sampleRate, options.mp3.bitRate);
+}
+
+function record(buffer) {
+  if (bufferCount++ < maxBuffers)
+    if (encoder)
+      encoder.encode(buffer);
+    else
+      recBuffers.push(buffer);
+  else
+    self.postMessage({ command: "timeout" });
+};
+
+function postProgress(progress) {
+  self.postMessage({ command: "progress", progress: progress });
+};
+
+function finish() {
+  if (recBuffers) {
+    postProgress(0);
+    encoder = new Mp3LameEncoder(sampleRate, options.mp3.bitRate);
+    var timeout = Date.now() + options.progressInterval;
+    while (recBuffers.length > 0) {
+      encoder.encode(recBuffers.shift());
+      var now = Date.now();
+      if (now > timeout) {
+        postProgress((bufferCount - recBuffers.length) / bufferCount);
+        timeout = now + options.progressInterval;
+      }
+    }
+    postProgress(1);
+  }
+  self.postMessage({
+    command: "complete",
+    blob: encoder.finish(options.mp3.mimeType)
+  });
+  cleanup();
+};
+
+function cleanup() {
+  encoder = recBuffers = undefined;
+  bufferCount = 0;
+}
+
+self.onmessage = function(event) {
+  var data = event.data;
+  switch (data.command) {
+    case "init":    init(data);                 break;
+    case "options": setOptions(data.options);   break;
+    case "start":   start(data.bufferSize);     break;
+    case "record":  record(data.buffer);        break;
+    case "finish":  finish();                   break;
+    case "cancel":  cleanup();
+  }
+};
+
+self.postMessage({ command: "loaded" });