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[wolnelektury.git] / apps / catalogue / utils.py
index 5ae9db5..fd74c94 100644 (file)
@@ -14,6 +14,7 @@ from django.http import HttpResponse
 from django.core.files.uploadedfile import UploadedFile
 from django.core.files.storage import DefaultStorage
 from django.utils.encoding import force_unicode
 from django.core.files.uploadedfile import UploadedFile
 from django.core.files.storage import DefaultStorage
 from django.utils.encoding import force_unicode
+from django.utils.translation import get_language
 from django.conf import settings
 from os import mkdir, path, unlink
 from errno import EEXIST, ENOENT
 from django.conf import settings
 from os import mkdir, path, unlink
 from errno import EEXIST, ENOENT
@@ -37,8 +38,12 @@ def get_random_hash(seed):
     return urlsafe_b64encode(sha_digest).replace('=', '').replace('_', '-').lower()
 
 
     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
     for tag in tags:
         result.setdefault(tag.category, []).append(tag)
     return result
@@ -187,6 +192,52 @@ class MultiQuerySet(object):
                     stop = total_len - len(items)
                     continue
 
                     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
+            for i in i_s:
+                def get_next():
+                    return self.querysets[i][sort_heads[i]]
+                try:
+                    if candidate is None:
+                        candidate = get_next()
+                    else:
+                        competitor = get_next()
+                        if self.sortfn(candidate, competitor) > 0:
+                            candidate = competitor
+                except IndexError:
+                    continue # continue next sort_head
+                sort_heads[i] += 1
+            # we have no more elements:
+            if candidate is None:
+                break
+            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
 
 def truncate_html_words(s, num, end_text='...'):
     """Truncates HTML to a certain number of words (not counting tags and
@@ -312,4 +363,12 @@ This can sometimes occupy lots of memory, so trim it here a bit.
         connection.queries = trim_to > 0 \
             and connection.queries[-trim_to:] \
             or []
         connection.queries = trim_to > 0 \
             and connection.queries[-trim_to:] \
             or []
-        
+
+
+def related_tag_name(tag_info, language=None):
+    return tag_info.get("name_%s" % (language or get_language()),
+        tag_info.get("name_%s" % settings.LANGUAGE_CODE, ""))
+
+
+def delete_from_cache_by_language(cache, key_template):
+    cache.delete_many([key_template % lc for lc, ln in settings.LANGUAGES])