Use urljoin for pmedia

redditbot.py

@@ -10,7 +10,7 @@ import functools
 import mimetypes
 import traceback
 from itertools import zip_longest
-from urllib.parse import urlparse, urlunparse
+from urllib.parse import urlparse, urlunparse, urljoin
 import yaml
 import asyncpraw
 import aiohttp
@@ -385,7 +385,7 @@ async def main():
                             tat += url
                         files = []
                         if pmedia:
-                            pmedia = urlunparse(urlparse(pmedia, 'https'))
+                            pmedia = urljoin(url, pmedia)
                             await _download_file(filename, pmedia)
                             files.append(filename)
                         if pdesc: