models.py

# Copyright (c) 2012 Johan Uhle
# 
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
# 
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
# 
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

from google.appengine.ext import db

import datetime
import logging

import utils

class Location(db.Model):
  
  location = db.GeoPtProperty(required=True)
  city = db.StringProperty()
  country = db.StringProperty()                  
  track_counter = db.IntegerProperty()
  last_time_updated = db.DateTimeProperty()      

class LocationGenreLastUpdate(db.Model):
  
  location = db.ReferenceProperty(reference_class=Location)
  genre = db.StringProperty()
  track_counter = db.IntegerProperty()
  last_time_updated = db.DateTimeProperty()
  
class User(db.Model):
  user_id = db.IntegerProperty(required=True)
  permalink = db.StringProperty()
  permalink_url = db.LinkProperty()
  username = db.StringProperty()
  fullname = db.StringProperty()
  avatar_url = db.LinkProperty()      
  location = db.ReferenceProperty(reference_class=Location) 

class Track(db.Model):
  
  track_id = db.IntegerProperty(required=True)
  permalink = db.StringProperty()
  permalink_url = db.LinkProperty()
  title = db.StringProperty()
  
  stream_url = db.LinkProperty()
  waveform_url = db.LinkProperty()
  artwork_url = db.LinkProperty() 
  purchase_url = db.LinkProperty()    
      
  created_at = db.DateTimeProperty()
  downloadable = db.BooleanProperty()
  original_format = db.StringProperty()
  release_date = db.DateProperty()
  release = db.StringProperty()
  isrc = db.StringProperty()   
  label_name = db.StringProperty()
  label_id = db.IntegerProperty()  
  license = db.StringProperty()
  genre = db.StringProperty()
  bpm = db.FloatProperty()
  key_signature = db.StringProperty()
  duration = db.IntegerProperty()
  description = db.TextProperty()
  
  user = db.ReferenceProperty(reference_class=User)
  location = db.ReferenceProperty(reference_class=Location)
  entry_created_at = db.DateTimeProperty(auto_now_add=True)

  # TODO: wrap into transaction?
  #@db.transactional(xg=True)
  def remove(self):
    def decrease_track_counter(element):
      logging.info(element.track_counter)
      element.track_counter -= 1
      if element.track_counter <= 0:
        logging.info("deleting element " + str(element)) + " with ID " + str(element.key().id())
        element.delete()
      else:
        logging.info("changed element " + str(element) +  " with ID " + str(element.key().id()) + " to " + str(element.track_counter))
        element.put()

    logging.info("id: " + str(self.key().id()) + " count: " + str(Track.all().filter('user', self.user.key()).count()))

    # delete user if this is the only track by this user
    if Track.all().filter('user', self.user.key()).count() <= 1:
      logging.info(self.user)
      self.user.delete()

    # delete location if this is the only track in this location
    # (no need to look at users because they don't exist without tracks)
    if Track.all().filter('location', self.location.key()).count() <= 1:
      logging.info("only track in location")
      # this is the last track for this location, so
      # delete it and it's locationgenrelastupdate
      for locationgenrelastupdate in self.location.locationgenrelastupdate_set.fetch(100, 0):
        logging.info("deleting locationgenrelastupdate")
        locationgenrelastupdate.delete()

      self.location.delete()
    else:
      logging.info("more tracks in location")
      # there are more tracks for this location, so only decrease counters
      for genre in utils.genres.iteritems():
        if self.genre in genre[1]:
          locgenre = self.location.locationgenrelastupdate_set.filter('genre', genre[0]).get()
          decrease_track_counter(locgenre)
          logging.info(self.location.locationgenrelastupdate_set.filter('genre', genre[0]).get().track_counter)
          break

      location = self.location
      decrease_track_counter(location)
      logging.info(self.location.track_counter)

    logging.info(self)
    self.delete()

  def created_minutes_ago(self):
    timedelta = datetime.datetime.now() - self.created_at     
    return ((timedelta.seconds + timedelta.days*86400) / 60)