from django.db import models


class PoliceOfficer(models.Model):
    """
    An officer of the NYPD.
    E.g. "Jake Peralta"
    """
    badge_number = models.IntegerField(primary_key=True)
    first_name = models.CharField(max_length=200)
    surname = models.CharField(max_length=200)
    rank = models.CharField(max_length=200)
    arrests = models.ManyToManyField(
        "Arrest",
        related_name="arresting_officers",
        help_text='All arrests made by the officer'
    )


class PoliceStation(models.Model):
    officers = models.ForeignKey("PoliceOfficer", on_delete=models.CASCADE)


class Precinct(PoliceStation):
    """
    A precinct of officers
    E.g. "Brookyln 99"
    """
    number = models.IntegerField(primary_key=True)
    burrough = models.CharField(max_length=20)
    captain = models.OneToOneField(PoliceOfficer, on_delete=models.CASCADE)

    class Meta:
        unique_together = ("burrough", "number")

    def natural_key(self):
        return (self.burrough, self.number)


class Division(PoliceStation):
    """
    A division of officers, not in the field.
    E.g. Major Crimes Unit
    """
    name = models.CharField(max_length=200)


class Arrest(models.Model):
    alleged_crime = models.CharField(max_length=20)
    perp = models.ForeignKey("Perpetrator", on_delete=models.CASCADE)
    arrest_date = models.DateField()
    processing_date = models.DateField()


class Perpetrator(models.Model):
    """
    A person who is accused of a crime.
    E.g. Doug Judy, aka. "The Pontiac Bandit"
    """
    first_name = models.CharField(max_length=200)
    surname = models.CharField(max_length=200)
    alias = models.CharField(max_length=200)