from django.test import TestCase
from django.conf import settings
from django.core.urlresolvers import reverse, NoReverseMatch
import os
import re

class TestUnresolveableUrls(TestCase):
    """ Look for url tags that wont reverse in templates """

    def test_broken_urls(self):
        """ Look for url tags that wont reverse """
        pattern = re.compile(r'{% +url +[\'"]([^\'"]+)[\'"] +%}')
        template_urls = self._find_matches_from_templates(pattern)
        for filename, url in template_urls:
            self._test_url_reverses(url, filename)

    def _test_url_reverses(self, url, template):
        try:
            result = reverse(url)
            self.assertIsNotNone(result, msg="url '%s' from template %s did not reverse" % (url, template))
        except NoReverseMatch, e:
            raise Exception("url '%s' from template %s did not reverse" % (url, template))

    def _find_matches_from_templates(self, pattern):
        template_dirs = settings.TEMPLATE_DIRS
        template_includes = []
        for template_dir in template_dirs:
            for subdir, dirs, files in os.walk(template_dir):
                for f in files:
                    template_path = os.path.join(subdir, f)
                    with open(os.path.join(template_dir, template_path), "r") as ifile:
                        matches = pattern.findall(ifile.read())
                        for i in matches:
                            template_includes.append((template_path, i))

        return template_includes