from odoo import models, fields, api
from odoo.exceptions import ValidationError

class TeacherAttendance(models.Model):
    _name = 'school.teacher.attendance'
    _description = 'Teacher Attendance'
    _order = 'date desc'

    teacher_id = fields.Many2one('res.partner', string='Student')
    date = fields.Date(string='Date', required=True, default=fields.Date.today)
    attendance_status = fields.Selection([
        ('present', 'Present'),
        ('absent', 'Absent'),
        ('on_leave', 'On Leave'),
        ('late', 'Late')
    ], string='Status', required=True, default='present')
    remarks = fields.Text(string='Remarks')

    @api.constrains('date', 'teacher_id')
    def _check_duplicate_attendance(self):
        for rec in self:
            existing = self.search([
                ('teacher_id', '=', rec.teacher_id.id),
                ('date', '=', rec.date),
                ('id', '!=', rec.id)
            ])
            if existing:
                raise ValidationError("Attendance for this teacher already exists on this date.")