newtagging refactor

[wolnelektury.git] / apps / catalogue / utils.py

diff --git a/apps/catalogue/utils.py b/apps/catalogue/utils.py
index edc287f..a0e834c 100644 (file)
--- a/apps/catalogue/utils.py
+++ b/apps/catalogue/utils.py
@@ -38,32 +38,17 @@ def get_random_hash(seed):
     return urlsafe_b64encode(sha_digest).replace('=', '').replace('_', '-').lower()
 
 
-def split_tags(tags):
-    result = {}
+def split_tags(tags, initial=None):
+    if initial is None:
+        result = {}
+    else:
+        result = initial
+
     for tag in tags:
         result.setdefault(tag.category, []).append(tag)
     return result
 
 
-def get_dynamic_path(media, filename, ext=None, maxlen=100):
-    from fnpdjango.utils.text.slughifi import slughifi
-
-    # how to put related book's slug here?
-    if not ext:
-        # BookMedia case
-        ext = media.formats[media.type].ext
-    if media is None or not media.name:
-        name = slughifi(filename.split(".")[0])
-    else:
-        name = slughifi(media.name)
-    return 'book/%s/%s.%s' % (ext, name[:maxlen-len('book/%s/.%s' % (ext, ext))-4], ext)
-
-
-# TODO: why is this hard-coded ?
-def book_upload_path(ext=None, maxlen=100):
-    return lambda *args: get_dynamic_path(*args, ext=ext, maxlen=maxlen)
-
-
 class ExistingFile(UploadedFile):
 
     def __init__(self, path, *args, **kwargs):
@@ -145,7 +130,7 @@ def remove_zip(zip_slug):
 class AttachmentHttpResponse(HttpResponse):
     """Response serving a file to be downloaded.
     """
-    def __init__ (self, file_path, file_name, mimetype):
+    def __init__(self, file_path, file_name, mimetype):
         super(AttachmentHttpResponse, self).__init__(mimetype=mimetype)
         self['Content-Disposition'] = 'attachment; filename=%s' % file_name
         self.file_path = file_path
@@ -159,15 +144,15 @@ class MultiQuerySet(object):
     def __init__(self, *args, **kwargs):
         self.querysets = args
         self._count = None
-    
+
     def count(self):
         if not self._count:
             self._count = sum(len(qs) for qs in self.querysets)
         return self._count
-    
+
     def __len__(self):
         return self.count()
-        
+
     def __getitem__(self, item):
         try:
             indices = (offset, stop, step) = item.indices(self.count())
@@ -188,6 +173,55 @@ class MultiQuerySet(object):
                     stop = total_len - len(items)
                     continue
 
+class SortedMultiQuerySet(MultiQuerySet):
+    def __init__(self, *args, **kwargs):
+        self.order_by = kwargs.pop('order_by', None)
+        self.sortfn = kwargs.pop('sortfn', None)
+        if self.order_by is not None:
+            self.sortfn = lambda a, b: cmp(getattr(a, self.order_by),
+                                           getattr(b, self.order_by))
+        super(SortedMultiQuerySet, self).__init__(*args, **kwargs)
+
+    def __getitem__(self, item):
+        sort_heads = [0] * len(self.querysets)
+        try:
+            indices = (offset, stop, step) = item.indices(self.count())
+        except AttributeError:
+            # it's not a slice - make it one
+            return self[item : item + 1][0]
+        items = []
+        total_len = stop - offset
+        skipped = 0
+        i_s = range(len(sort_heads))
+
+        while len(items) < total_len:
+            candidate = None
+            candidate_i = None
+            for i in i_s:
+                def get_next():
+                    return self.querysets[i][sort_heads[i]]
+                try:
+                    if candidate is None:
+                        candidate = get_next()
+                        candidate_i = i
+                    else:
+                        competitor = get_next()
+                        if self.sortfn(candidate, competitor) > 0:
+                            candidate = competitor
+                            candidate_i = i
+                except IndexError:
+                    continue # continue next sort_head
+            # we have no more elements:
+            if candidate is None:
+                break
+            sort_heads[candidate_i] += 1
+            if skipped < offset:
+                skipped += 1
+                continue # continue next item
+            items.append(candidate)
+
+        return items
+
 
 def truncate_html_words(s, num, end_text='...'):
     """Truncates HTML to a certain number of words (not counting tags and