from django.db import models


class EsExamRequirementStudent(models.Model):
    exam_requirement = models.ForeignKey("api.EsExamRequirement", on_delete=models.CASCADE, null=True)
    student = models.ForeignKey("api.EsStudent", on_delete=models.CASCADE, null=True)
    created_by = models.BigIntegerField(null=True)
    created_at = models.DateTimeField(auto_now_add=True)
    updated_by = models.BigIntegerField(null=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        db_table = "es_exam_requirement_student"
        constraints = [
            models.UniqueConstraint(
                fields=["exam_requirement", "student"],
                name="unique_exam_requirement_student",
            )
        ]

    def __str__(self):
        return f"{self.exam_requirement_id}-{self.student_id}"