From b0f06948326d86ee4f2abe3e8d1dc24d64165a79 Mon Sep 17 00:00:00 2001
From: Annika Backstrom <annika@sixohthree.com>
Date: Sun, 9 Apr 2017 12:30:20 -0400
Subject: [PATCH] Create modules for MediaPlayer and TagReader

---
 jukebox/{children.js => child-process.js} | 42 ++++-------------------
 jukebox/media-player.js                   | 15 ++++++++
 jukebox/tag-reader.js                     | 15 ++++++++
 player.js                                 | 31 +++++++++++------
 4 files changed, 57 insertions(+), 46 deletions(-)
 rename jukebox/{children.js => child-process.js} (52%)
 create mode 100644 jukebox/media-player.js
 create mode 100644 jukebox/tag-reader.js

diff --git a/jukebox/children.js b/jukebox/child-process.js
similarity index 52%
rename from jukebox/children.js
rename to jukebox/child-process.js
index 214d0ad..6582c01 100644
--- a/jukebox/children.js
+++ b/jukebox/child-process.js
@@ -4,17 +4,16 @@
 // there enough commonalities to warrant a base class?
 
 const spawn = require('child_process').spawn;
-
 const EventEmitter = require('events').EventEmitter;
 
-const TAGREADER = 'tagreader';
-const MP3PLAYER = 'mpg321';
-
-class ChildEmitter extends EventEmitter {
-  constructor(process) {
+module.exports.ChildProcessEmitter = class ChildProcessEmitter extends EventEmitter {
+  constructor(command) {
     super();
 
-    this.childProcess = process;
+    var cmd = command[0],
+        args = command.slice(1);
+
+    this.childProcess = spawn(cmd, args);
 
     this.childProcess.on('error', function(err) {
       this.emit('process_error', err);
@@ -45,33 +44,4 @@ class ChildEmitter extends EventEmitter {
   }
 }
 
-function launchChild(name, command) {
-  var cmd = command[0],
-    args = command.slice(1);
-
-  return spawn(cmd, args);
-}
-
-exports.init = function(config) {
-  // Set up tag reader
-  var tagreader = launchChild(TAGREADER, config.tag_reader);
-  exports.tagreader = new ChildEmitter(tagreader);
-
-  // set up mp3 player
-  var mp3player = launchChild(MP3PLAYER, config.mpg321);
-  exports.mp3player = new ChildEmitter(mp3player);
-};
-
-exports.exitHandler = function(options, err) {
-  console.log('[player] closing children');
-  if (err) console.log(err.stack);
-
-  module.exports.tagreader.kill();
-  module.exports.mp3player.kill();
-
-  if (options.exit) {
-    process.exit();
-  }
-};
-
 // vim:set ts=2 sw=2 et:
diff --git a/jukebox/media-player.js b/jukebox/media-player.js
new file mode 100644
index 0000000..f0af95d
--- /dev/null
+++ b/jukebox/media-player.js
@@ -0,0 +1,15 @@
+"use strict";
+
+const ChildProcessEmitter = require('./child-process').ChildProcessEmitter;
+
+class MediaPlayer extends ChildProcessEmitter {
+    constructor(config) {
+      super(config.mpg321);
+    }
+}
+
+module.exports = function(config) {
+    return new MediaPlayer(config);
+};
+
+// vim:set ts=2 sw=2 et:
diff --git a/jukebox/tag-reader.js b/jukebox/tag-reader.js
new file mode 100644
index 0000000..c44ed73
--- /dev/null
+++ b/jukebox/tag-reader.js
@@ -0,0 +1,15 @@
+"use strict";
+
+const ChildProcessEmitter = require('./child-process').ChildProcessEmitter;
+
+class TagReader extends ChildProcessEmitter {
+    constructor(config) {
+      super(config.tag_reader);
+    }
+}
+
+module.exports = function(config) {
+    return new TagReader(config);
+};
+
+// vim:set ts=2 sw=2 et:
diff --git a/player.js b/player.js
index af89077..4214410 100644
--- a/player.js
+++ b/player.js
@@ -9,7 +9,8 @@ const views = require('./jukebox/views')(__dirname + '/templates/');
 const express = require('express');
 const logger = require('morgan')
 
-const children = require('./jukebox/children');
+const MediaPlayer = require('./jukebox/media-player')(config);
+const TagReader = require('./jukebox/tag-reader')(config);
 
 var app = express();
 var server = require('http').createServer();
@@ -20,10 +21,20 @@ var wss = new WebSocketServer({server: server});
 
 var play_log = [];
 
-children.init(config);
+function exitHandler(options, err) {
+  console.log('[player] closing children');
+  if (err) console.log(err.stack);
 
-process.on('exit', children.exitHandler.bind(null));
-process.on('SIGINT', children.exitHandler.bind(null, {exit:true}));
+  TagReader.kill();
+  MediaPlayer.kill();
+
+  if (options.exit) {
+    process.exit();
+  }
+};
+
+process.on('exit', exitHandler.bind(null));
+process.on('SIGINT', exitHandler.bind(null, {exit:true}));
 
 function setupChildLogging(name, child) {
   child.on('process_error', (err) => {
@@ -39,16 +50,16 @@ function setupChildLogging(name, child) {
   });
 }
 
-setupChildLogging('tagreader', children.tagreader);
-setupChildLogging('mp3player', children.mp3player);
+setupChildLogging('tagreader', TagReader);
+setupChildLogging('mediaplayer', MediaPlayer);
 
-children.tagreader.on('message', (data) => {
+TagReader.on('message', (data) => {
   processLine(data);
 });
 
 if (config.debug) {
-  children.mp3player.on('message', (data) => {
-    console.log(`[mp3player] stdout: ${data}`);
+  MediaPlayer.on('message', (data) => {
+    console.log(`[mediaplayer] stdout: ${data}`);
   });
 }
 
@@ -103,7 +114,7 @@ function processLine(data) {
     debounce_until = Date.now() / 1000 + wait_sec;
     if (action) {
       console.log(`[action] [${action}] for [${last_tag}]`);
-      children.mp3player.send(action + "\n");
+      MediaPlayer.send(action + "\n");
     }
   });
 }