src/catalogue/helpers.py

   1 # This file is part of FNP-Redakcja, licensed under GNU Affero GPLv3 or later.
   2 # Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
   3 #
   4 from datetime import date
   5 from functools import wraps
   6 from os.path import join
   7 from os import listdir, stat
   8 from shutil import move, rmtree
   9 from django.conf import settings
  10 import re
  11 import filecmp
  12
  13 from django.db.models import Count
  14
  15
  16 def active_tab(tab):
  17     """
  18         View decorator, which puts tab info on a request.
  19     """
  20     def wrapper(f):
  21         @wraps(f)
  22         def wrapped(request, *args, **kwargs):
  23             request.catalogue_active_tab = tab
  24             return f(request, *args, **kwargs)
  25         return wrapped
  26     return wrapper
  27
  28
  29 def cached_in_field(field_name):
  30     def decorator(f):
  31         @property
  32         @wraps(f)
  33         def wrapped(self, *args, **kwargs):
  34             value = getattr(self, field_name)
  35             if value is None:
  36                 value = f(self, *args, **kwargs)
  37                 type(self)._default_manager.filter(pk=self.pk).update(**{field_name: value})
  38             return value
  39         return wrapped
  40     return decorator
  41
  42
  43 def parse_isodate(isodate):
  44     try:
  45         return date(*[int(p) for p in isodate.split('-')])
  46     except (AttributeError, TypeError, ValueError):
  47         raise ValueError("Not a date in ISO format.")
  48
  49
  50 class GalleryMerger(object):
  51     def __init__(self, dest_gallery, src_gallery):
  52         self.dest = dest_gallery
  53         self.src = src_gallery
  54         self.dest_size = None
  55         self.src_size = None
  56         self.num_deleted = 0
  57
  58     @staticmethod
  59     def path(gallery):
  60         return join(settings.MEDIA_ROOT, settings.IMAGE_DIR, gallery)
  61
  62     @staticmethod
  63     def get_prefix(name):
  64         m = re.match(r"^([0-9])-", name)
  65         if m:
  66             return int(m.groups()[0])
  67         return None
  68
  69     @staticmethod
  70     def set_prefix(name, prefix, always=False):
  71         m = not always and re.match(r"^([0-9])-", name)
  72         return "%1d-%s" % (prefix, m and name[2:] or name)
  73
  74     @property
  75     def was_merged(self):
  76         "Check if we have gallery size recorded"
  77         return self.dest_size is not None
  78
  79     def merge(self):
  80         if not self.dest:
  81             return self.src
  82         if not self.src:
  83             return self.dest
  84
  85         files = listdir(self.path(self.dest))
  86         files.sort()
  87         self.dest_size = len(files)
  88         files_other = listdir(self.path(self.src))
  89         files_other.sort()
  90         self.src_size = len(files_other)
  91
  92         if files and files_other:
  93             if filecmp.cmp(
  94                     join(self.path(self.dest), files[-1]),
  95                     join(self.path(self.src), files_other[0]),
  96                     False
  97                     ):
  98                 files_other.pop(0)
  99                 self.num_deleted = 1
 100
 101         prefixes = {}
 102         renamed_files = {}
 103         renamed_files_other = {}
 104         last_pfx = -1
 105
 106         # check if all elements of my files have a prefix
 107         files_prefixed = True
 108         for f in files:
 109             p = self.get_prefix(f)
 110             if p:
 111                 if p > last_pfx: last_pfx = p
 112             else:
 113                 files_prefixed = False
 114                 break
 115
 116         # if not, add a 0 prefix to them
 117         if not files_prefixed:
 118             prefixes[0] = 0
 119             for f in files:
 120                 renamed_files[f] = self.set_prefix(f, 0, True)
 121
 122         # two cases here - either all are prefixed or not.
 123         files_other_prefixed = True
 124         for f in files_other:
 125             pfx = self.get_prefix(f)
 126             if pfx is not None:
 127                 if not pfx in prefixes:
 128                     last_pfx += 1
 129                     prefixes[pfx] = last_pfx
 130                 renamed_files_other[f] = self.set_prefix(f, prefixes[pfx])
 131             else:
 132                 # ops, not all files here were prefixed.
 133                 files_other_prefixed = False
 134                 break
 135
 136         # just set a 1- prefix to all of them
 137         if not files_other_prefixed:
 138             for f in files_other:
 139                 renamed_files_other[f] = self.set_prefix(f, 1, True)
 140
 141         # finally, move / rename files.
 142         for frm, to in renamed_files.items():
 143             move(join(self.path(self.dest), frm),
 144                         join(self.path(self.dest), to))
 145         for frm, to in renamed_files_other.items():
 146             move(join(self.path(self.src), frm),
 147                         join(self.path(self.dest), to))
 148
 149         rmtree(join(self.path(self.src)))
 150         return self.dest