From 98bb35d4d1c2624501cbaa9e55751df85c82fa2d Mon Sep 17 00:00:00 2001
From: Thomas Adamcik <thomas@adamcik.no>
Date: Mon, 20 May 2013 23:54:48 +0200
Subject: [PATCH] scanner: Convert to using library updater.

This version of the scanner switches to using the updater API, in other words
we are now fairly close to being able to plug in alternate libraries for local
files and populate them with mopidy-scan.
---
 mopidy/scanner.py | 70 ++++++++++++++++++-----------------------------
 1 file changed, 27 insertions(+), 43 deletions(-)

diff --git a/mopidy/scanner.py b/mopidy/scanner.py
index ba8f2ff9..1127264a 100644
--- a/mopidy/scanner.py
+++ b/mopidy/scanner.py
@@ -5,7 +5,6 @@ import datetime
 import logging
 import os
 import sys
-import tempfile
 
 import gobject
 gobject.threads_init()
@@ -29,7 +28,6 @@ import gst
 
 from mopidy import config as config_lib, ext
 from mopidy.audio import dummy as dummy_audio
-from mopidy.frontends.mpd import translator as mpd_translator
 from mopidy.models import Track, Artist, Album
 from mopidy.utils import log, path, versioning
 
@@ -56,74 +54,60 @@ def main():
         logging.warning('Config value local/media_dir is not set.')
         return
 
-    # TODO: missing error checking and other default setup code.
+    # TODO: missing config error checking and other default setup code.
 
     audio = dummy_audio.DummyAudio()
     local_backend_classes = extensions['local'].get_backend_classes()
     local_backend = local_backend_classes[0](config, audio)
+    local_updater = local_backend.updater
 
-    tracks = {}  # Current lib.
-    update = []  # Paths to rescan for updates/adds.
-    remove = []  # Paths to delete from lib.
+    media_dir = config['local']['media_dir']
 
-    for track in local_backend.library.search().tracks:
-        tracks[track.uri] = track
+    uris_library = set()
+    uris_update = set()
+    uris_remove = set()
 
-    logging.info('Checking %d files from library.', len(tracks))
-    for track in tracks.itervalues():
+    logging.info('Checking tracks from library.')
+    for track in local_updater.load():
         try:
             stat = os.stat(path.uri_to_path(track.uri))
             if int(stat.st_mtime) > track.last_modified:
-                update.append(track.uri)
+                uris_update.add(track.uri)
+            uris_library.add(track.uri)
         except OSError:
-            remove.append(track.uri)
+            uris_remove.add(track.uri)
 
-    logging.info('Removing %d files from library.', len(remove))
-    for uri in remove:
-        del tracks[uri]
+    logging.info('Removing %d moved or deleted tracks.', len(uris_remove))
+    for uri in uris_remove:
+        local_updater.remove(uri)
 
-    logging.info('Checking %s for changes.', config['local']['media_dir'])
-    for p in path.find_files(config['local']['media_dir']):
-        uri = path.path_to_uri(p)
-        if uri not in tracks:
-            update.append(uri)
+    logging.info('Checking %s for new or modified tracks.', media_dir)
+    for uri in path.find_uris(config['local']['media_dir']):
+        if uri not in uris_library:
+            uris_update.add(uri)
+
+    logging.info('Found %d new or changed tracks.', len(uris_update))
 
     def store(data):
         track = translator(data)
-        tracks[track.uri] = track
+        local_updater.add(track)
         logging.debug('Added %s', track.uri)
 
     def debug(uri, error, debug):
         logging.warning('Failed %s: %s', uri, error)
         logging.debug('Debug info for %s: %s', uri, debug)
 
-
-    logging.info('Scanning %d new/changed files.', len(update))
-    scanner = Scanner(update, store, debug)
+    logging.info('Scanning new and changed tracks.')
+    # TODO: just pass the library in instead?
+    scanner = Scanner(uris_update, store, debug)
     try:
         scanner.start()
     except KeyboardInterrupt:
         scanner.stop()
+        raise
 
-    logging.info('Done scanning; writing tag cache to temporary file.')
-
-    directory, basename = os.path.split(config['local']['tag_cache_file'])
-    tmp = tempfile.NamedTemporaryFile(
-        prefix=basename + '.', dir=directory, delete=False)
-
-    try:
-        for row in mpd_translator.tracks_to_tag_cache_format(
-                tracks.values(), config['local']['media_dir']):
-            if len(row) == 1:
-                tmp.write(('%s\n' % row).encode('utf-8'))
-            else:
-                tmp.write(('%s: %s\n' % row).encode('utf-8'))
-
-        logging.info('Done writing; overwriting active tag cache.')
-        os.rename(tmp.name, config['local']['tag_cache_file'])
-    finally:
-        if os.path.exists(tmp.name):
-            os.remove(tmp.name)
+    logging.info('Done scanning; commiting changes.')
+    local_updater.commit()
 
 
 def parse_args():