Fix populate songs script, add time remaining info

SQL/populate_songs.py

 # -*- coding: utf-8 -*-
 # run in Django shell ONLY!!!
 # python manage.py shell
-# >>> exec(open('./SQL/populate_songs.py').read())
-
+# copy-paste everything then
+# >>> run()
 
+import time
 from core.models import *
 
 def extract_song_title(s):
@@ -20,13 +21,59 @@ def extract_song_title(s):
 def prettify_genre(g):
     return ', '.join([h.replace('_',' ') for h in g.split()])
 
-for i in Song.objects.filter(song_name__startswith="."):
-    songlst = extract_song_title(i.song_name)
-    for e in songlst:
-        Song.objects.create(song_name=e, genre=prettify_genre(i.genre), artist=i.artist, album=i.album)
-    # uncomment the next line if you want to delete the original entry after parsing
-    i.delete()
+def parse_raw(n_albums):
+    idx = 1
+    total_time = 0
+    for i in Song.objects.filter(song_name__startswith="."):
+        print('Processing entry %d of %d...' % (idx, n_albums))
+        t0 = time.time()
+        songlst = extract_song_title(i.song_name)
+        for e in songlst:
+            # print('    FOUND: ' + e)
+            Song.objects.create(song_name=e, genre=prettify_genre(i.genre), artist=i.artist, album=i.album)
+        tf = time.time()
+        delta = tf-t0
+        total_time += delta
+        # time remaining = (avg time per album)*(# remaining albums)
+        trem = (total_time/idx)*(n_albums-idx)
+        print('[INFO] Parsing entry %d took %.3fs' % (idx, delta))
+        print('[INFO] Approx. time remaining: %d:%02d' % (trem//60, int(trem)%60))
+        idx += 1
+
+def cleanup(n_albums):
+    print('Deleting original raw entries...')
+    didx = 1
+    for i in Song.objects.filter(song_name__startswith="."):
+        print('Deleting raw entry %d of %d...' % (didx, n_albums))
+        i.delete()
+        didx += 1
+
+# if something messed up above, run this
+def revert():
+    rm = len(Song.objects.exclude(song_name__startswith="."))
+    ridx = 1
+    ttime = 0
+    for song in Song.objects.exclude(song_name__startswith="."):
+        t0 = time.time()
+        song.delete()
+        tf = time.time()
+        delta = tf-t0
+        ttime += delta
+        trem = (ttime/ridx)*(rm-ridx)
+        print('[INFO] Approx. time remaining: %d:%02d' % (trem//60, int(trem)%60))
+        ridx += 1
+
+def purge_all():
+    resp = input('[WARN] Delete ALL entries? [y/N] ')
+    if resp == 'y':
+        for song in Song.objects.all():
+            song.delete()
+        print('[INFO] All entries deleted!')
 
-# if something messed up above, uncomment these lines
-# for song in Song.objects.exclude(song_name__startswith="."):
-#     song.delete()
\ No newline at end of file
+def run():
+    print('Populate songs')
+    qu = Song.objects.filter(song_name__startswith=".")
+    n_albums = len(qu)
+    print('Found %d entries yet to be parsed' % n_albums)
+    parse_raw(n_albums)
+    cleanup(n_albums)
\ No newline at end of file