From 84e9340b561aed8396105644c3fdce42dbaf4e6c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kjist=C3=B3f?= <mrtoth@strongds.hu>
Date: Sun, 15 Jan 2017 22:28:37 +0100
Subject: [PATCH] general refactor & commenting

---
 coub-dl.py | 31 +++++++++++++++++++++----------
 1 file changed, 21 insertions(+), 10 deletions(-)

diff --git a/coub-dl.py b/coub-dl.py
index 426aca7..46b8a6a 100644
--- a/coub-dl.py
+++ b/coub-dl.py
@@ -31,6 +31,19 @@ def getDuration(ffprobe_output):
         raise ValueError('Cannot process ffprobe output!')
     return duration
 
+def downloadStreams():
+    call(('/usr/bin/env', 'youtube-dl', '--extract-audio',
+                                        '--output', '{}.%(ext)s'.format(FILES[Stream.AUDIO]),
+                                        URL))
+    call(('/usr/bin/env', 'youtube-dl', '--output', '{}.%(ext)s'.format(FILES[Stream.VIDEO]),
+                                        URL))
+
+def readExtensions():
+    for file in listdir():
+        for filename in FILES:
+            if match('^{}.*'.format(FILES[filename]), file):
+                FILES[filename] = file
+
 
 FILES = {Stream.AUDIO: 'audio', Stream.VIDEO: 'video',
          File.LIST: 'list.txt', File.LOOP: 'loop', File.OUTPUT: 'output.mp4'}
@@ -38,23 +51,17 @@ OUTPUT_KEYS = [File.OUTPUT]
 URL = argv[1] if len(argv) > 0 else ''  # youtube-dl error message will be shown if ''
 
 
-call(('/usr/bin/env', 'youtube-dl', '--extract-audio',
-                                    '--output',         '{}.%(ext)s'.format(FILES[Stream.AUDIO]),
-                                    URL))
-call(('/usr/bin/env', 'youtube-dl', '--output',         '{}.%(ext)s'.format(FILES[Stream.VIDEO]),
-                                    URL))
-
-for file in listdir():
-    for filename in FILES:
-        if match('^{}.*'.format(FILES[filename]), file):
-            FILES[filename] = file
+downloadStreams()
+readExtensions()
 
+# get stream lengths via ffprobe
 audioData= getDuration(getCmdStdErr(('/usr/bin/env', 'ffprobe', FILES[Stream.AUDIO]))).split(':')
 videoData = getDuration(getCmdStdErr(('/usr/bin/env', 'ffprobe', FILES[Stream.VIDEO]))).split(':')
 
 audioLen = timedelta(hours=float(audioData[0]), minutes=float(audioData[1]), seconds=float(audioData[2]))
 videoLen = timedelta(hours=float(videoData[0]), minutes=float(videoData[1]), seconds=float(videoData[2]))
 
+# decide which stream needs some looping
 longer = audioLen if audioLen > videoLen else videoLen
 shorter = audioLen if audioLen < videoLen else videoLen
 shorterFile = FILES[Stream.AUDIO] if audioLen < videoLen else FILES[Stream.VIDEO]
@@ -62,19 +69,23 @@ FILES[File.LOOP] += splitext(shorterFile)[1]
 
 timesLoop = ceil(longer.seconds / shorter.seconds)
 
+# write concat helper file for ffmpeg
 with open(FILES[File.LIST], 'w') as f:
     for i in range(timesLoop):
         print("file '{}'".format(shorterFile), file=f)
 
 
+# fetch video title
 FILES[File.OUTPUT] = check_output(('/usr/bin/env', 'youtube-dl', '--get-title', argv[1])).decode('utf-8').strip() + '.mp4'
 
+# loop & mux
 call(('/usr/bin/env', 'ffmpeg', '-f', 'concat', '-i', FILES[File.LIST], '-c', 'copy', FILES[File.LOOP]))
 call(('/usr/bin/env', 'ffmpeg', '-i', FILES[File.LOOP],
                                 '-i', FILES[Stream.AUDIO],
                                 '-map', '0', '-map', '1',
                                 '-c', 'copy', FILES[File.OUTPUT]))
 
+# cleanup
 for key in FILES:
     if key not in OUTPUT_KEYS:
         remove(FILES[key])