from django.db import models

_weekdays = {
    0 : 'M',
    1 : 'T',
    2 : 'W',
    3 : 'R',
    4 : 'F',
    5 : 'Sa',
    6 : 'Su',
}

class Lot(models.Model):
    name = models.CharField(primary_key=True, max_length=50)
    description = models.CharField(max_length=50)
    lat = models.DecimalField(max_digits=8, decimal_places=6)
    lng = models.DecimalField(max_digits=8, decimal_places=6)
    times = models.ManyToManyField('ParkTime', through='ParkRule')

    def toJSON(self):
        return {
            'name' : self.name,
            'description' : self.description,
            'lat' : float(self.lat),
            'lng' : float(self.lng),
        }

    def __unicode__(self):
        return u'%s' % (self.name)

class Tag(models.Model):
    name = models.CharField(primary_key=True, max_length=5)
    lots = models.ManyToManyField('ParkTime', through='ParkRule')

    def __unicode__(self):
        return u'%s' % (self.name)

class ParkTime(models.Model):
    start = models.TimeField()
    end = models.TimeField()
    days = models.ManyToManyField('Weekday')

    def __unicode__(self):
        (startStr, endStr) = (self.start.strftime("%H:%M"), self.end.strftime("%H:%M"))
        daysStr = ''.join([str(day) for day in self.days.all()])
        return u'%s - %s %s' % (startStr, endStr, daysStr)

class ParkRule(models.Model):
    lot = models.ForeignKey(Lot)
    tag = models.ForeignKey(Tag)
    when = models.ForeignKey(ParkTime)
    canPark = models.BooleanField()
    takesEffect = models.DateField()
    lastsUntil = models.DateField()

    def __unicode__(self):
        return u'%s in %s: %s' % (self.tag, self.lot, self.when)

class Weekday(models.Model):
    day = models.IntegerField()

    def __unicode__(self):
        return u'%s' % (_weekdays[self.day])