Odoo 19 for Healthcare:
Patient Management, Inventory & HIPAA Compliance

class HealthcareAppointment(models.Model):
    _name = 'healthcare.appointment'
    _description = 'Patient Appointment'
    _inherit = ['mail.thread', 'mail.activity.mixin']
    _order = 'date_start desc'

    patient_id = fields.Many2one(
        'healthcare.patient', required=True, tracking=True,
    )
    physician_id = fields.Many2one(
        'hr.employee', string='Physician', required=True,
        domain="[('department_id.name', '=', 'Medical')]",
        tracking=True,
    )
    date_start = fields.Datetime(
        string='Appointment Date', required=True, tracking=True,
    )
    date_end = fields.Datetime(string='End Time')
    duration = fields.Float(
        string='Duration (hours)', default=0.5,
    )
    appointment_type = fields.Selection([
        ('consultation', 'General Consultation'),
        ('followup', 'Follow-Up'),
        ('lab', 'Lab Work'),
        ('imaging', 'Imaging'),
        ('telemedicine', 'Telemedicine'),
        ('emergency', 'Emergency'),
    ], string='Type', default='consultation', tracking=True)
    state = fields.Selection([
        ('scheduled', 'Scheduled'),
        ('confirmed', 'Confirmed'),
        ('checked_in', 'Checked In'),
        ('in_progress', 'In Progress'),
        ('completed', 'Completed'),
        ('cancelled', 'Cancelled'),
        ('no_show', 'No Show'),
    ], default='scheduled', tracking=True)
    reason = fields.Text(string='Reason for Visit')
    diagnosis = fields.Html(string='Diagnosis Notes')
    calendar_event_id = fields.Many2one(
        'calendar.event', string='Calendar Event',
    )
    telemedicine_link = fields.Char(string='Video Call Link')

    @api.model_create_multi
    def create(self, vals_list):
        appointments = super().create(vals_list)
        for appt in appointments:
            appt._create_calendar_event()
            appt._schedule_reminders()
        return appointments

    def _create_calendar_event(self):
        event = self.env['calendar.event'].create({
            'name': f"Appt: {self.patient_id.display_name}",
            'start': self.date_start,
            'stop': self.date_end or fields.Datetime.add(
                self.date_start, hours=self.duration
            ),
            'user_id': self.physician_id.user_id.id,
            'partner_ids': [
                (4, self.patient_id.partner_id.id),
            ],
        })
        self.calendar_event_id = event.id

    def _schedule_reminders(self):
        """Schedule SMS + email 24h and 2h before appointment."""
        self.env['mail.activity'].create({
            'activity_type_id': self.env.ref(
                'mail.mail_activity_data_todo'
            ).id,
            'summary': f'Upcoming appointment: '
                       f'{self.patient_id.display_name}',
            'date_deadline': fields.Date.to_string(
                self.date_start - relativedelta(days=1)
            ),
            'user_id': self.physician_id.user_id.id,
            'res_model_id': self.env['ir.model']._get_id(self._name),
            'res_id': self.id,
        })

class HealthcarePrescription(models.Model):
    _name = 'healthcare.prescription'
    _description = 'Medical Prescription'
    _inherit = ['mail.thread']
    _order = 'date_prescribed desc'

    patient_id = fields.Many2one(
        'healthcare.patient', required=True, tracking=True,
    )
    physician_id = fields.Many2one(
        'hr.employee', string='Prescribing Physician',
        required=True, tracking=True,
    )
    date_prescribed = fields.Date(
        default=fields.Date.today, tracking=True,
    )
    line_ids = fields.One2many(
        'healthcare.prescription.line', 'prescription_id',
        string='Medications',
    )
    state = fields.Selection([
        ('draft', 'Draft'),
        ('confirmed', 'Confirmed'),
        ('dispensed', 'Dispensed'),
        ('completed', 'Completed'),
        ('cancelled', 'Cancelled'),
    ], default='draft', tracking=True)
    appointment_id = fields.Many2one(
        'healthcare.appointment', string='Related Appointment',
    )
    notes = fields.Text(string='Pharmacist Notes')

    def action_confirm(self):
        self._check_drug_interactions()
        self._check_allergies()
        self.write({{'state': 'confirmed'}})

    def _check_drug_interactions(self):
        """Cross-reference active prescriptions for conflicts."""
        for line in self.line_ids:
            active_meds = self.env['healthcare.prescription.line'].search([
                ('prescription_id.patient_id', '=', self.patient_id.id),
                ('prescription_id.state', 'in',
                 ['confirmed', 'dispensed']),
                ('prescription_id', '!=', self.id),
            ])
            for active in active_meds:
                interactions = line.product_id.drug_interaction_ids
                if active.product_id in interactions:
                    raise models.ValidationError(
                        f"Drug interaction: "
                        f"{line.product_id.name} conflicts with "
                        f"{active.product_id.name} (active Rx "
                        f"#{active.prescription_id.id})."
                    )

    def _check_allergies(self):
        """Warn if prescribed medication matches known allergies."""
        patient_allergies = self.patient_id.allergy_ids
        for line in self.line_ids:
            med_allergens = line.product_id.allergen_ids
            overlap = patient_allergies & med_allergens
            if overlap:
                raise models.ValidationError(
                    f"Allergy alert: {self.patient_id.display_name} "
                    f"is allergic to "
                    f"{', '.join(overlap.mapped('name'))}. "
                    f"Cannot prescribe {line.product_id.name}."
                )


class HealthcarePrescriptionLine(models.Model):
    _name = 'healthcare.prescription.line'
    _description = 'Prescription Line'

    prescription_id = fields.Many2one(
        'healthcare.prescription', required=True,
        ondelete='cascade',
    )
    product_id = fields.Many2one(
        'product.product', string='Medication',
        domain="[('categ_id.is_medical', '=', True)]",
        required=True,
    )
    dosage = fields.Char(string='Dosage', required=True)
    frequency = fields.Char(
        string='Frequency', required=True,
        help='e.g., "Twice daily", "Every 8 hours"',
    )
    duration_days = fields.Integer(string='Duration (days)')
    quantity = fields.Float(string='Quantity to Dispense')
    refills_allowed = fields.Integer(string='Refills Allowed')
    refills_used = fields.Integer(string='Refills Used', default=0)
    lot_id = fields.Many2one(
        'stock.lot', string='Dispensed Lot',
        help='Lot/batch number actually dispensed to patient.',
    )