Avoid letting subtitle files ruining navigation buttons

Have different naming convention for navigation button links and titles

pystream/models/squire.py

@@ -96,17 +96,19 @@ def get_iter(filename: pathlib.PurePath) -> Union[Tuple[str, str], Tuple[None, N
         Tuple[str, str]:
         Tuple of previous file and next file.
     """
-    dir_content = sorted(os.listdir(filename.parent), key=lambda x: natural_sort_key(x))
+    # Extract only the file formats that are supported
+    dir_content = sorted(
+        (file for file in os.listdir(filename.parent) if pathlib.PosixPath(file).suffix in config.env.file_formats),
+        key=lambda x: natural_sort_key(x)
+    )
     idx = dir_content.index(filename.name)
     try:
         previous_ = dir_content[idx - 1]
-        assert pathlib.PosixPath(previous_).suffix in config.env.file_formats
-    except (IndexError, AssertionError):
+    except IndexError:
         previous_ = None
     try:
         next_ = dir_content[idx + 1]
-        assert pathlib.PosixPath(next_).suffix in config.env.file_formats
-    except (IndexError, AssertionError):
+    except IndexError:
         next_ = None
     return previous_, next_
 

pystream/routers/video.py

@@ -92,13 +92,18 @@ async def stream_video(request: Request,
             }
         )
     if pure_path.exists():
-        prev_, next_ = squire.get_iter(pure_path)
         attrs = {
             "request": request, "video_title": video_path,
             "home": config.static.home_endpoint, "logout": config.static.logout_endpoint,
-            "path": f"{config.static.streaming_endpoint}?{config.static.query_param}={urlparse.quote(str(pure_path))}",
-            "previous": prev_, "next": next_
+            "path": f"{config.static.streaming_endpoint}?{config.static.query_param}={urlparse.quote(str(pure_path))}"
         }
+        prev_, next_ = squire.get_iter(pure_path)
+        if prev_:
+            attrs["previous"] = urlparse.quote(prev_)
+            attrs["previous_title"] = prev_
+        if next_:
+            attrs["next"] = urlparse.quote(next_)
+            attrs["next_title"] = next_
         # set default to avoid broken image sign in thumbnail
         preview_src = os.path.join(pathlib.PurePath(__file__).parent, "blank.jpg")
         if config.env.auto_thumbnail:

pystream/templates/land.html

@@ -129,12 +129,12 @@ <h1>{{ video_title }}</h1>
         </p>
     </video>
     {% if previous %}
-        <button class="iter" style="float: left" onclick="window.location='{{ previous }}'" title="{{ previous }}">
+        <button class="iter" style="float: left" onclick="window.location='{{ previous }}'" title="{{ previous_title }}">
             <i class="fa fa-backward"></i> Previous
         </button>
     {% endif %}
     {% if next %}
-        <button class="iter" style="float: right" onclick="window.location='{{ next }}'" title="{{ next }}">
+        <button class="iter" style="float: right" onclick="window.location='{{ next }}'" title="{{ next_title }}">
             Next <i class="fa fa-forward"></i>
         </button>
     {% endif %}