from django.core.validators import MinValueValidator
from django.db import models


MODE_CHOICES = ['FM', 'AFSK', 'BFSK', 'APRS', 'SSTV', 'CW', 'FMN']


class Satellite(models.Model):
    """Model for SatNOGS satellites."""
    norad_cat_id = models.PositiveIntegerField()
    name = models.CharField(max_length=45)

    def __unicode__(self):
        return self.name


class Transponder(models.Model):
    """Model for antennas transponders."""
    description = models.TextField()
    alive = models.BooleanField(default=True)
    uplink_low = models.PositiveIntegerField(blank=True, null=True)
    uplink_high = models.PositiveIntegerField(blank=True, null=True)
    downlink_low = models.PositiveIntegerField(blank=True, null=True)
    downlink_high = models.PositiveIntegerField(blank=True, null=True)
    mode = models.CharField(choices=zip(MODE_CHOICES, MODE_CHOICES),
                            max_length=10)
    invert = models.BooleanField(default=False)
    baud = models.FloatField(validators=[MinValueValidator(0)])
    satellite = models.ForeignKey(Satellite, related_name='transponder',
                                  null=True)
    approved = models.BooleanField(default=False)
    suggestion = models.ForeignKey('self', blank=True, null=True,
                                   on_delete=models.SET_NULL,
                                   related_name="suggestions")

    def __unicode__(self):
        return self.description