Don't repeat videos if possible

.gitignore

@@ -1 +1,2 @@
 token.secret
+seen-vids.dat

beatbot.py

@@ -2,6 +2,7 @@ import mastodon
 import random
 import requests
 import re
+import pickle
 
 def randline(fname):
     with open(fname) as afile:
@@ -19,11 +20,36 @@ def bot():
     search_term = f'+lofi {genre} +beats {verb1} {verb2}'
     text = f"lo-fi {genre} beats to {verb1} and {verb2} to"
 
+    try:
+        with open('seen-vids.dat', 'rb') as seen:
+            seen_vids = pickle.load(seen)
+    except Exception:
+        seen_vids = set()
+
     query = requests.get(f'https://www.youtube.com/results?search_query={search_term}')
-    vids = re.findall(r'watch\?v=([^"]{11})"', query.text)
-    if vids:
-        print(f'{query.url} : {len(vids)} results')
-        text += f'\n\nhttps://youtube.com/watch?v={random.choice(vids)}'
+    video_ids = re.findall(r'watch\?v=([^"]{11})"', query.text)
+
+    yt_id = None
+
+    random.shuffle(video_ids)
+
+    # try to find a random video we haven't used before
+    for vid in video_ids:
+        if vid not in seen_vids:
+            yt_id = vid
+            break
+
+    if not yt_id and video_ids:
+        # nothing new, so just select a random one (list is already shuffled)
+        yt_id = video_ids[0]
+
+    if yt_id:
+        text += f'\n\nhttps://youtube.com/watch?v={yt_id}'
+
+        # remember that we used it already
+        seen_vids.add(yt_id)
+        with open('seen-vids.dat', 'wb') as seen:
+            pickle.dump(seen_vids, seen)
 
     print(text)