From fcf4ba3eb9d92d6f3b64fa9b71f6eeaada2b1430 Mon Sep 17 00:00:00 2001
From: Keith Edmunds <kae@tiger-computing.co.uk>
Date: Sun, 15 Aug 2021 12:52:50 +0100
Subject: [PATCH] Implement full database scan

---
 app/model.py  |  6 ++++
 app/songdb.py | 88 ++++++++++++++++++++++++++++++++++++++++-----------
 2 files changed, 76 insertions(+), 18 deletions(-)

diff --git a/app/model.py b/app/model.py
index 1619e00..d9ea5e4 100644
--- a/app/model.py
+++ b/app/model.py
@@ -463,6 +463,12 @@ class Tracks(Base):
 
         return [a[0] for a in session.query(Tracks.path).all()]
 
+    @staticmethod
+    def get_all_tracks(session):
+        "Return a list of all tracks"
+
+        return session.query(Tracks).all()
+
     @classmethod
     def get_or_create(cls, session, path):
         DEBUG(f"Tracks.get_or_create(path={path})")
diff --git a/app/songdb.py b/app/songdb.py
index 42063cd..6366357 100755
--- a/app/songdb.py
+++ b/app/songdb.py
@@ -115,10 +115,78 @@ def create_track_from_file(session, path):
     return track
 
 
-def full_update_db():
+def full_update_db(session):
     "Rescan all entries in database"
 
-    print("Full scan not yet implemented")
+    def log(msg):
+        INFO(f"full_update_db(): {msg}")
+
+    def check_change(track_id, title, attribute, old, new):
+        if new > (old * 1.1) or new < (old * 0.9):
+            log(
+                "\n"
+                f"track[{track_id}] ({title}) "
+                f"{attribute} updated from {old} to {new}"
+            )
+
+    # Start with normal update to add new tracks and remove any missing
+    # files
+    log("update_db()")
+    update_db(session)
+
+    # Now update track length, silence and fade for every track in
+    # database
+
+    tracks = Tracks.get_all_tracks(session)
+    total_tracks = len(tracks)
+    log(f"Processing {total_tracks} tracks")
+    track_count = 0
+    for track in tracks:
+        track_count += 1
+        print(f"\rTrack {track_count} of {total_tracks}", end='')
+
+        # Sanity check
+        tag = get_music_info(track.path)
+        if not tag['title']:
+            log(f"track[{track.id}] {track.title=}: No tag title")
+            continue
+
+        if track.artist:
+            if track.artist != tag['artist']:
+                log(
+                    f"track[{track.id}] artist mismatch: "
+                    f"{track.artist=} {tag['artist']=}"
+                )
+                continue
+
+        # Update title
+        if track.title != tag['title']:
+            track.title = tag['title']
+
+        # Update numbers; log if more than 10% different
+        duration = int(round(
+            tag['duration'], Config.MILLISECOND_SIGFIGS) * 1000)
+        check_change(track.id, track.title, "duration", track.duration,
+                     duration)
+        track.duration = duration
+
+        audio = get_audio_segment(track.path)
+
+        start_gap = leading_silence(audio)
+        check_change(track.id, track.title, "start_gap", track.start_gap,
+                     start_gap)
+        track.start_gap = start_gap
+
+        fade_at = fade_point(audio)
+        check_change(track.id, track.title, "fade_at", track.fade_at,
+                     fade_at)
+        track.fade_at = fade_at
+
+        silence_at = trailing_silence(audio)
+        check_change(track.id, track.title, "silence_at", track.silence_at,
+                     silence_at)
+        track.silence_at = silence_at
+        session.commit()
 
 
 def get_audio_segment(path):
@@ -196,22 +264,6 @@ def fade_point(audio_segment, fade_threshold=0,
     return int(trim_ms)
 
 
-# Current unused (1 June 2021)
-# def rescan_database(session):
-#
-#     tracks = Tracks.get_all_tracks(session)
-#     total_tracks = len(tracks)
-#     track_count = 0
-#     for track in tracks:
-#         track_count += 1
-#         print(f"Track {track_count} of {total_tracks}")
-#         audio = get_audio_segment(track.path)
-#         track.start_gap = leading_silence(audio)
-#         track.fade_at = fade_point(audio)
-#         track.silence_at = trailing_silence(audio)
-#         session.commit()
-
-
 def trailing_silence(audio_segment, silence_threshold=-50.0,
                      chunk_size=Config.AUDIO_SEGMENT_CHUNK_SIZE):
     return fade_point(audio_segment, silence_threshold, chunk_size)