from django.db import models

class Subject(models.Model):
    name = models.CharField(max_length=100)
    code = models.CharField(max_length=20, unique=True)
    description = models.TextField(blank=True)

    def __str__(self):
        return self.name

    class Meta:
        ordering = ['name']

class Teacher(models.Model):
    GENDER_CHOICES = [('M', 'Male'), ('F', 'Female'), ('O', 'Other')]

    first_name = models.CharField(max_length=100)
    last_name = models.CharField(max_length=100)
    teacher_id = models.CharField(max_length=20, unique=True)
    email = models.EmailField(unique=True)
    phone = models.CharField(max_length=20, blank=True)
    gender = models.CharField(max_length=1, choices=GENDER_CHOICES, default='M')
    subjects = models.ManyToManyField(Subject, blank=True, related_name='teachers')
    qualification = models.CharField(max_length=200, blank=True)
    hire_date = models.DateField(auto_now_add=True)
    photo = models.ImageField(upload_to='teachers/', blank=True, null=True)
    is_active = models.BooleanField(default=True)
    created_at = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return f"{self.first_name} {self.last_name}"

    @property
    def full_name(self):
        return f"{self.first_name} {self.last_name}"

    class Meta:
        ordering = ['last_name', 'first_name']