Add opt-in diagnostic logging

serato_doctor/cli.py

@@ -3,6 +3,7 @@ import argparse
 
 from serato_doctor.config import ScanConfig
 from serato_doctor.crate_parser import parse_crates
+from serato_doctor.logging import configure_logging
 from serato_doctor.models.library import Library
 from serato_doctor.scanner import scan_audio
 from serato_doctor.report import write_csv, write_missing_report
@@ -20,6 +21,10 @@ def main():
         default=[],
         help="Old library root stored in crates; may be supplied more than once",
     )
+    parser.add_argument(
+        "--verbose", action="store_true", help="Write diagnostic progress to stderr"
+    )
+    parser.add_argument("--log-file", help="Write scan progress to a log file")
     args = parser.parse_args()
 
     config = ScanConfig.build(
@@ -28,7 +33,13 @@ def main():
         out=Path(args.out),
         report=Path(args.report),
         reference_roots=(Path(root) for root in args.reference_root),
+        verbose=args.verbose,
+        log_file=Path(args.log_file) if args.log_file else None,
     )
+    logger = configure_logging(config.verbose, config.log_file)
+    logger.info("Starting read-only library scan")
+    logger.debug("Serato directory: %s", config.serato)
+    logger.debug("Music directory: %s", config.music)
 
     library = Library.build(
         references=parse_crates(
@@ -38,9 +49,13 @@ def main():
     )
     results = library.reconcile_by_filename()
     missing_count = sum(1 for result in results if not result.exists_by_filename)
+    logger.info("Parsed %d crate references", len(library.references))
+    logger.info("Scanned %d disk tracks", len(library.tracks))
+    logger.info("Found %d references missing by filename", missing_count)
 
     write_csv(results, config.out)
     write_missing_report(results, config.report)
+    logger.info("Wrote CSV and missing-reference reports")
 
     print(f"Crate references: {len(library.references)}")
     print(f"Disk tracks: {len(library.tracks)}")