Add feed deletion and single video addition features

- Implemented DELETE /api/channels/<id> to remove channels and cleanup downloaded files
- Added delete button to channels page with confirmation dialog
- Added functionality to add single videos via URL
- Updated navigation menu

feed_parser.py

@@ -8,6 +8,7 @@ from datetime import datetime
 import feedparser
 from typing import Dict, List, Optional
 import re
+import yt_dlp
 
 from sqlalchemy.orm import Session
 from sqlalchemy.exc import IntegrityError
@@ -198,3 +199,133 @@ class YouTubeFeedParser:
 
         db_session.commit()
         return channel
+
+
+def fetch_single_video(video_url: str) -> Optional[Dict]:
+    """Fetch metadata for a single YouTube video using yt-dlp.
+
+    Args:
+        video_url: YouTube video URL
+
+    Returns:
+        Dictionary with video metadata or None if fetch fails
+    """
+    # Check if URL contains "shorts" - reject shorts
+    if "shorts" in video_url.lower():
+        return None
+
+    try:
+        ydl_opts = {
+            'quiet': True,
+            'no_warnings': True,
+            'extract_flat': False,
+        }
+
+        with yt_dlp.YoutubeDL(ydl_opts) as ydl:
+            info = ydl.extract_info(video_url, download=False)
+
+            if not info:
+                return None
+
+            # Extract video ID from URL
+            video_id = info.get('id')
+            if not video_id:
+                return None
+
+            # Get channel info
+            channel_id = info.get('channel_id')
+            channel_name = info.get('channel') or info.get('uploader')
+            channel_url = info.get('channel_url') or f"https://www.youtube.com/channel/{channel_id}"
+
+            # Get thumbnail - prefer maxresdefault, fall back to other qualities
+            thumbnail_url = None
+            if info.get('thumbnails'):
+                # Get highest quality thumbnail
+                thumbnail_url = info['thumbnails'][-1].get('url')
+            elif info.get('thumbnail'):
+                thumbnail_url = info.get('thumbnail')
+
+            # Parse upload date
+            upload_date_str = info.get('upload_date')
+            if upload_date_str:
+                # Format: YYYYMMDD
+                published_at = datetime.strptime(upload_date_str, '%Y%m%d')
+            else:
+                published_at = datetime.utcnow()
+
+            return {
+                'video_id': video_id,
+                'title': info.get('title'),
+                'video_url': f"https://www.youtube.com/watch?v={video_id}",
+                'description': info.get('description'),
+                'thumbnail_url': thumbnail_url,
+                'published_at': published_at,
+                'channel_id': channel_id,
+                'channel_name': channel_name,
+                'channel_url': channel_url,
+            }
+
+    except Exception as e:
+        print(f"Error fetching video metadata: {e}")
+        return None
+
+
+def save_single_video_to_db(db_session: Session, video_data: Dict, user_id: int) -> VideoEntry:
+    """Save a single video to the database.
+
+    Args:
+        db_session: SQLAlchemy database session
+        video_data: Dictionary containing video metadata (from fetch_single_video)
+        user_id: ID of the user adding this video
+
+    Returns:
+        The VideoEntry model instance
+
+    This method:
+    - Creates channel if it doesn't exist for this user
+    - Creates video entry if it doesn't exist
+    - Returns existing video if already in database
+    """
+    # Get or create channel for this user
+    channel = db_session.query(Channel).filter_by(
+        user_id=user_id,
+        channel_id=video_data['channel_id']
+    ).first()
+
+    if not channel:
+        # Create new channel
+        channel = Channel(
+            user_id=user_id,
+            channel_id=video_data['channel_id'],
+            title=video_data['channel_name'],
+            link=video_data['channel_url'],
+            rss_url=f"https://www.youtube.com/feeds/videos.xml?channel_id={video_data['channel_id']}",
+            last_fetched_at=datetime.utcnow()
+        )
+        db_session.add(channel)
+        db_session.flush()  # Get the channel ID
+
+    # Check if video already exists for this channel
+    existing_video = db_session.query(VideoEntry).filter_by(
+        channel_id=channel.id,
+        video_id=video_data['video_id']
+    ).first()
+
+    if existing_video:
+        return existing_video
+
+    # Create new video entry
+    video = VideoEntry(
+        channel_id=channel.id,
+        video_id=video_data['video_id'],
+        title=video_data['title'],
+        video_url=video_data['video_url'],
+        thumbnail_url=video_data.get('thumbnail_url'),
+        description=video_data.get('description'),
+        published_at=video_data['published_at'],
+        created_at=datetime.utcnow()
+    )
+    db_session.add(video)
+    db_session.commit()
+
+    return video