Change the tags column in the device view to a Collections column that allows the user to directly edit collections on the device. Note that if the user deletes a collection taht corresponds to some data in the calibre library that would be turned intoa coleection, then the deletion has no effect, on device reconnect

src/calibre/devices/interface.py

@@ -396,14 +396,6 @@ class BookList(list):
         ''' Return True if the the device supports tags (collections) for this book list. '''
         raise NotImplementedError()
 
-    def set_tags(self, book, tags):
-        '''
-        Set the tags for C{book} to C{tags}.
-        @param tags: A list of strings. Can be empty.
-        @param book: A book object that is in this BookList.
-        '''
-        raise NotImplementedError()
-
     def add_book(self, book, replace_metadata):
         '''
         Add the book to the booklist. Intent is to maintain any device-internal

src/calibre/devices/prs505/sony_cache.py

@@ -101,16 +101,25 @@ class XMLCache(object):
 
     # Playlist management {{{
     def purge_broken_playlist_items(self, root):
-        for item in root.xpath(
+        for pl in root.xpath('//*[local-name()="playlist"]'):
-            '//*[local-name()="playlist"]/*[local-name()="item"]'):
+            seen = set([])
-            id_ = item.get('id', None)
+            for item in list(pl):
-            if id_ is None or not root.xpath(
+                id_ = item.get('id', None)
-                '//*[local-name()!="item" and @id="%s"]'%id_):
+                if id_ is None or id_ in seen or not root.xpath(
-                if DEBUG:
+                    '//*[local-name()!="item" and @id="%s"]'%id_):
-                    prints('Purging broken playlist item:',
+                    if DEBUG:
-                            etree.tostring(item, with_tail=False))
+                        if id_ is None:
-                item.getparent().remove(item)
+                            cause = 'invalid id'
-
+                        elif id_ in seen:
+                            cause = 'duplicate item'
+                        else:
+                            cause = 'id not found'
+                        prints('Purging broken playlist item:',
+                                id_, 'from playlist:', pl.get('title', None),
+                                'because:', cause)
+                    item.getparent().remove(item)
+                    continue
+                seen.add(id_)
 
     def prune_empty_playlists(self):
         for i, root in self.record_roots.items():
@@ -175,6 +184,8 @@ class XMLCache(object):
     # }}}
 
     def fix_ids(self): # {{{
+        if DEBUG:
+            prints('Running fix_ids()')
 
         def ensure_numeric_ids(root):
             idmap = {}
@@ -294,13 +305,8 @@ class XMLCache(object):
                     break
                 if book.lpath in playlist_map:
                     tags = playlist_map[book.lpath]
-                    if tags:
+                    book.device_collections = tags
-                        if DEBUG:
+
-                            prints('Adding tags:', tags, 'to', book.title)
-                        if not book.tags:
-                            book.tags = []
-                        book.tags = list(book.tags)
-                        book.tags += tags
     # }}}
 
     # Update XML from JSON {{{
@@ -359,7 +365,25 @@ class XMLCache(object):
                         nsmap=playlist.nsmap, attrib={'id':id_})
                 playlist.append(item)
 
-
+        # Delete playlist entries not in collections
+        for playlist in root.xpath('//*[local-name()="playlist"]'):
+            title = playlist.get('title', None)
+            if title not in collections:
+                if DEBUG:
+                    prints('Deleting playlist:', playlist.get('title', ''))
+                playlist.getparent().remove(playlist)
+                continue
+            books = collections[title]
+            records = [self.book_by_lpath(b.lpath, root) for b in books]
+            records = [x for x in records if x is not None]
+            ids = [x.get('id', None) for x in records]
+            ids = [x for x in ids if x is not None]
+            for item in list(playlist):
+                if item.get('id', None) not in ids:
+                    if DEBUG:
+                        prints('Deleting item:', item.get('id', ''),
+                                'from playlist:', playlist.get('title', ''))
+                    playlist.remove(item)
 
     def create_text_record(self, root, bl_id, lpath):
         namespace = self.namespaces[bl_id]
@@ -414,8 +438,19 @@ class XMLCache(object):
                     child.iterchildren(reversed=True).next().tail = '\n'+'\t'*level
             root.iterchildren(reversed=True).next().tail = '\n'+'\t'*(level-1)
 
+    def move_playlists_to_bottom(self):
+        for root in self.record_roots.values():
+            seen = []
+            for pl in root.xpath('//*[local-name()="playlist"]'):
+                pl.getparent().remove(pl)
+                seen.append(pl)
+            for pl in seen:
+                root.append(pl)
+
+
     def write(self):
         for i, path in self.paths.items():
+            self.move_playlists_to_bottom()
             self.cleanup_whitespace(i)
             raw = etree.tostring(self.roots[i], encoding='UTF-8',
                     xml_declaration=True)

src/calibre/devices/usbms/books.py

@@ -14,14 +14,14 @@ from calibre import isbytestring
 
 class Book(MetaInformation):
 
-    BOOK_ATTRS = ['lpath', 'size', 'mime']
+    BOOK_ATTRS = ['lpath', 'size', 'mime', 'device_collections']
 
     JSON_ATTRS = [
         'lpath', 'title', 'authors', 'mime', 'size', 'tags', 'author_sort',
         'title_sort', 'comments', 'category', 'publisher', 'series',
         'series_index', 'rating', 'isbn', 'language', 'application_id',
         'book_producer', 'lccn', 'lcc', 'ddc', 'rights', 'publication_type',
-        'uuid'
+        'uuid',
     ]
 
     def __init__(self, prefix, lpath, size=None, other=None):
@@ -29,6 +29,7 @@ class Book(MetaInformation):
 
         MetaInformation.__init__(self, '')
 
+        self.device_collections = []
         self.path = os.path.join(prefix, lpath)
         if os.sep == '\\':
             self.path = self.path.replace('/', '\\')
@@ -45,27 +46,7 @@ class Book(MetaInformation):
             self.smart_update(other)
 
     def __eq__(self, other):
-        spath = self.path
+        return self.path == getattr(other, 'path', None)
-        opath = other.path
-
-        if not isinstance(self.path, unicode):
-            try:
-                spath = unicode(self.path)
-            except:
-                try:
-                    spath = self.path.decode(filesystem_encoding)
-                except:
-                    spath = self.path
-        if not isinstance(other.path, unicode):
-            try:
-                opath = unicode(other.path)
-            except:
-                try:
-                    opath = other.path.decode(filesystem_encoding)
-                except:
-                    opath = other.path
-
-        return spath == opath
 
     @dynamic_property
     def db_id(self):
@@ -119,9 +100,6 @@ class BookList(_BookList):
     def supports_tags(self):
         return True
 
-    def set_tags(self, book, tags):
-        book.tags = tags
-
     def add_book(self, book, replace_metadata):
         if book not in self:
             self.append(book)
@@ -134,6 +112,7 @@ class BookList(_BookList):
     def get_collections(self, collection_attributes):
         collections = {}
         series_categories = set([])
+        collection_attributes = list(collection_attributes)+['device_collections']
         for attr in collection_attributes:
             for book in self:
                 val = getattr(book, attr, None)
@@ -147,9 +126,12 @@ class BookList(_BookList):
                 for category in val:
                     if category not in collections:
                         collections[category] = []
-                    collections[category].append(book)
+                    if book not in collections[category]:
-                    if attr == 'series':
+                        collections[category].append(book)
-                        series_categories.add(category)
+                        if attr == 'series':
+                            series_categories.add(category)
+
+        # Sort collections
         for category, books in collections.items():
             def tgetter(x):
                 return getattr(x, 'title_sort', 'zzzz')

src/calibre/gui2/library/models.py

@@ -807,7 +807,7 @@ class DeviceBooksModel(BooksModel): # {{{
                 'authors'    : _('Author(s)'),
                 'timestamp'  : _('Date'),
                 'size'       : _('Size'),
-                'tags'       : _('Tags')
+                'tags'       : _('Collections')
                 }
         self.marked_for_deletion = {}
         self.search_engine = OnDeviceSearch(self)
@@ -1000,7 +1000,7 @@ class DeviceBooksModel(BooksModel): # {{{
                 dt = dt_factory(dt, assume_utc=True, as_utc=False)
                 return QVariant(strftime(TIME_FMT, dt.timetuple()))
             elif cname == 'tags':
-                tags = self.db[self.map[row]].tags
+                tags = self.db[self.map[row]].device_collections
                 if tags:
                     return QVariant(', '.join(tags))
         elif role == Qt.ToolTipRole and index.isValid():
@@ -1047,7 +1047,7 @@ class DeviceBooksModel(BooksModel): # {{{
             elif cname == 'tags':
                 tags = [i.strip() for i in val.split(',')]
                 tags = [t for t in tags if t]
-                self.db.set_tags(self.db[idx], tags)
+                self.db[idx].device_collections = tags
             self.dataChanged.emit(index, index)
             self.booklist_dirtied.emit()
             done = True