Code layout change.

[wolnelektury.git] / src / reporting / templatetags / reporting_stats.py

diff --git a/src/reporting/templatetags/reporting_stats.py b/src/reporting/templatetags/reporting_stats.py
new file mode 100755 (executable)
index 0000000..7bbe23d
--- /dev/null
+++ b/src/reporting/templatetags/reporting_stats.py
@@ -0,0 +1,57 @@
+# -*- coding: utf-8 -*-
+# This file is part of Wolnelektury, licensed under GNU Affero GPLv3 or later.
+# Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
+#
+from functools import wraps
+from django import template
+from catalogue.models import Book
+
+
+register = template.Library()
+
+class StatsNode(template.Node):
+    def __init__(self, value, varname=None):
+        self.value = value
+        self.varname = varname
+
+    def render(self, context):
+        if self.varname:
+            context[self.varname] = self.value
+            return ''
+        else:
+            return self.value
+
+
+def register_counter(f):
+    """Turns a simple counting function into a registered counter tag.
+
+    You can run a counter tag as a simple {% tag_name %} tag, or
+    as {% tag_name var_name %} to store the result in a variable.
+
+    """
+    @wraps(f)
+    def wrapped(parser, token):
+        try:
+            tag_name, args = token.contents.split(None, 1)
+        except ValueError:
+            args = None
+        return StatsNode(f(), args)
+
+    return register.tag(wrapped)
+
+
+@register_counter
+def count_books_all():
+    return Book.objects.all().count()
+
+@register_counter
+def count_books():
+    return Book.objects.filter(children=None).count()
+
+@register_counter
+def count_books_parent():
+    return Book.objects.exclude(children=None).count()
+
+@register_counter
+def count_books_root():
+    return Book.objects.filter(parent=None).count()