feat: Update summary generation to scale words based on video duration

summarize_yt/cli.py

@@ -45,15 +45,18 @@ def sanitize_filename(url: str) -> str:
     return f"{timestamp}_{video_id if video_id else 'video'}"
 
 
-def ensure_transcript_dir() -> Path:
-    """Create and return path to transcript directory."""
-    transcript_dir = Path.home() / ".yts" / "transcripts"
+def ensure_yts_dirs() -> Tuple[Path, Path]:
+    """Create and return paths to transcript and summary directories."""
+    base_dir = Path.home() / ".yts"
+    transcript_dir = base_dir / "transcripts"
+    summary_dir = base_dir / "summaries"
     transcript_dir.mkdir(parents=True, exist_ok=True)
-    return transcript_dir
+    summary_dir.mkdir(parents=True, exist_ok=True)
+    return transcript_dir, summary_dir
 
 
-def download_subtitles(url: str, quiet: bool = False) -> Tuple[bool, Optional[Path]]:
-    """Download subtitles from YouTube using yt-dlp."""
+def download_subtitles(url: str, quiet: bool = False) -> Tuple[bool, Optional[Path], int]:
+    """Download subtitles from YouTube using yt-dlp and return success, path, and duration in minutes."""
     try:
         ydl_opts = {
             'skip_download': True,
@@ -63,6 +66,13 @@ def download_subtitles(url: str, quiet: bool = False) -> Tuple[bool, Optional[Pa
             'no_warnings': quiet,
         }
         
+        # First get video duration
+        info_opts = dict(ydl_opts)
+        info_opts['extract_flat'] = True
+        with YoutubeDL(info_opts) as ydl:
+            info = ydl.extract_info(url, download=False)
+            duration_mins = int(info.get('duration', 0) / 60)
+
         if not quiet:
             print(f"Debug: Downloading subtitles for {url}")
 
@@ -80,7 +90,7 @@ def download_subtitles(url: str, quiet: bool = False) -> Tuple[bool, Optional[Pa
             print("No VTT file found after download", file=sys.stderr)
             return False, None
 
-        return True, vtt_files[0]
+        return True, vtt_files[0], duration_mins
 
     except Exception as e:
         print(f"Error during subtitle download: {str(e)}", file=sys.stderr)
@@ -141,7 +151,7 @@ def process_file(input_path: Path, output_path: Path | None = None, quiet: bool
 
 def save_transcript(text: str, url: str, prompt: str) -> Path:
     """Save transcript with metadata to ~/.yts/transcripts/."""
-    transcript_dir = ensure_transcript_dir()
+    transcript_dir, _ = ensure_yts_dirs()
     filename = sanitize_filename(url) + ".txt"
     filepath = transcript_dir / filename
 
@@ -173,7 +183,7 @@ def cleanup_files(vtt_path: Optional[Path]):
         print(f"Warning: Could not clean up temporary files: {str(e)}", file=sys.stderr)
 
 
-def get_summary_from_claude(text: str, prompt: str = "Please summarize this transcript in 500 words or less") -> str:
+def get_summary_from_claude(text: str, duration_mins: int, prompt: str = None) -> str:
     """Send text to Claude API for summarization."""
     try:
         api_key = os.environ.get("ANTHROPIC_API_KEY")
@@ -181,9 +191,15 @@ def get_summary_from_claude(text: str, prompt: str = "Please summarize this tran
             raise ValueError("ANTHROPIC_API_KEY environment variable not set")
 
         client = anthropic.Anthropic()
+        # Calculate target word count based on duration
+        target_words = max(500, (duration_mins // 10) * 500)
+        
+        if prompt is None:
+            prompt = f"Please summarize this transcript in approximately {target_words} words"
+            
         message = client.messages.create(
             model="claude-3-sonnet-20240229",
-            max_tokens=1024,
+            max_tokens=2048,  # Increased for longer summaries
             temperature=0,
             system="You are a helpful assistant that summarizes transcripts accurately and concisely.",
             messages=[{"role": "user", "content": f"{prompt}:\n\n{text}"}],
@@ -203,7 +219,7 @@ def main():
     parser.add_argument("--keep-files", action="store_true", help="Don't delete downloaded VTT files")
     parser.add_argument("--transcript", action="store_true", help="Include full transcript in output")
     parser.add_argument(
-        "--prompt", default="Please summarize this transcript in 500 words or less", help="Custom prompt for Claude"
+        "--prompt", help="Custom prompt for Claude (default: auto-calculated based on video length)"
     )
     parser.add_argument("-y", "--yes", action="store_true", help="Skip cost confirmation")
 
@@ -212,7 +228,7 @@ def main():
     # Download subtitles
     if not args.quiet:
         print("Downloading subtitles...")
-    success, vtt_path = download_subtitles(args.url, args.quiet)
+    success, vtt_path, duration_mins = download_subtitles(args.url, args.quiet)
     if not success:
         cleanup_files(None)
         sys.exit(1)
@@ -243,7 +259,7 @@ def main():
     # Get summary from Claude
     if not args.quiet:
         print("\nGetting summary from Claude...")
-    summary = get_summary_from_claude(cleaned_text, args.prompt)
+    summary = get_summary_from_claude(cleaned_text, duration_mins, args.prompt)
 
     # Prepare output
     output = ""
@@ -253,15 +269,20 @@ def main():
         output += "\n\n=== Summary ===\n\n"
     output += summary
 
-    # Output results
-    output_path = args.output
-    if output_path:
-        with open(output_path, "w", encoding="utf-8") as f:
+    # Save summary
+    _, summary_dir = ensure_yts_dirs()
+    summary_filename = sanitize_filename(args.url) + "_summary.txt"
+    summary_path = summary_dir / summary_filename
+    
+    with open(summary_path, "w", encoding="utf-8") as f:
+        f.write(output)
+    print(f"\nSummary saved to: {summary_path}")
+
+    # If output path specified, also save there
+    if args.output:
+        with open(args.output, "w", encoding="utf-8") as f:
             f.write(output)
-        print(f"\nSummary saved to: {output_path}")
-    else:
-        print("\n=== Summary ===")
-        print(output)
+        print(f"Summary also saved to: {args.output}")
 
     # Cleanup downloaded files unless --keep-files is specified
     if not args.keep_files: