Notifications & Alerts

import re

class PHISanitizer:
    """
    Strips protected health information from notification messages
    before they are sent through external push services.
    """

    PATTERNS = [
        # MRN patterns
        (r'MRN[-:]?\s*[\w-]+', ''),
        # SSN patterns
        (r'\b\d{3}-\d{2}-\d{4}\b', ''),
        # Phone numbers
        (r'\+?1?\s*\(?\d{3}\)?[\s.-]?\d{3}[\s.-]?\d{4}', ''),
        # Specific BP values (e.g., "182/110 mmHg")
        (r'\b\d{2,3}/\d{2,3}\s*mmHg\b', 'abnormal blood pressure'),
        # Heart rate values (e.g., "142 bpm")
        (r'\b\d{2,3}\s*bpm\b', 'abnormal heart rate'),
        # SpO2 values (e.g., "88%")
        (r'\b\d{2,3}%\s*(?:SpO2|oxygen)', 'low oxygen saturation'),
        # Blood glucose (e.g., "320 mg/dL")
        (r'\b\d{2,3}\s*mg/dL\b', 'abnormal glucose level'),
        # Temperature (e.g., "103.2°F")
        (r'\b\d{2,3}\.\d°?[FC]\b', 'abnormal temperature'),
    ]

    @classmethod
    def sanitize(cls, message: str, patient_names: list[str] = None) -> str:
        """Remove all PHI patterns from a notification message."""
        sanitized = message

        # Replace patient names
        if patient_names:
            for name in patient_names:
                sanitized = sanitized.replace(name, 'a patient')

        # Apply regex patterns
        for pattern, replacement in cls.PATTERNS:
            sanitized = re.sub(pattern, replacement, sanitized, flags=re.IGNORECASE)

        # Clean up double spaces and trailing punctuation artifacts
        sanitized = re.sub(r'\s{2,}', ' ', sanitized).strip()

        return sanitized

curl -X PATCH /api/v1/users/me/notification-preferences/ \
  -H "Authorization: Bearer <token>" \
  -H "Content-Type: application/json" \
  -d '{
    "channels": {
      "escalations": { "push": true, "in_app": true },
      "alerts": { "push": true, "in_app": true },
      "reminders": { "push": false, "in_app": true },
      "daily_digest": { "push": true, "in_app": true, "time": "07:00" }
    },
    "quiet_hours": {
      "enabled": true,
      "start": "22:00",
      "end": "06:00",
      "exceptions": ["escalations"]
    }
  }'

curl -X POST /api/v1/notifications/tokens/register/ \
  -H "Authorization: Bearer <token>" \
  -H "Content-Type: application/json" \
  -d '{
    "token": "ExponentPushToken[xxxxxxxxxxxxxxxxxxxxxx]",
    "type": "expo",
    "device_id": "device-uuid-abc-123",
    "platform": "ios",
    "app_version": "1.2.0"
  }'

def process_observation(observation):
    """
    Called for every new vital sign observation.
    Checks against patient thresholds and generates alerts.
    """
    patient = observation.patient
    thresholds = patient.get_thresholds(observation.vital_type)

    if not thresholds:
        return  # No thresholds configured for this vital type

    value = observation.value_quantity

    # Determine severity based on threshold breach
    severity = None
    if value >= thresholds.high_critical or value <= thresholds.low_critical:
        severity = 'critical'
    elif value >= thresholds.high_warning or value <= thresholds.low_warning:
        severity = 'warning'

    if severity:
        # Create alert record
        alert = Alert.objects.create(
            patient=patient,
            observation=observation,
            vital_type=observation.vital_type,
            severity=severity,
            value=value,
            threshold_breached=thresholds.get_breached_threshold(value),
            message=f"{observation.get_vital_display()} reading of {value} "
                    f"exceeds {severity} threshold"
        )

        # Trigger notification
        send_vital_alert_notification.delay(
            alert_id=alert.id,
            recipient_ids=patient.get_care_team_ids()
        )

        # Update triage summary
        recalculate_risk_score.delay(patient_id=patient.id)

curl -X POST /api/v1/alerts/{alert_id}/acknowledge/ \
  -H "Authorization: Bearer <token>" \
  -H "Content-Type: application/json" \
  -d '{
    "outcome": "resolved",
    "clinical_note": "Patient contacted by phone. Reports taking medication as prescribed. BP reading likely due to physical activity. No intervention required.",
    "follow_up_required": false
  }'

# Response:
{
  "id": "alert-uuid-789",
  "status": "resolved",
  "acknowledged_by": "Dr. Sarah Chen",
  "acknowledged_at": "2026-02-06T14:45:00Z",
  "outcome": "resolved",
  "audit_trail": [
    {
      "action": "created",
      "timestamp": "2026-02-06T14:28:12Z",
      "actor": "system"
    },
    {
      "action": "notification_sent",
      "timestamp": "2026-02-06T14:28:15Z",
      "actor": "system",
      "detail": "Push notification sent to Dr. Sarah Chen"
    },
    {
      "action": "acknowledged",
      "timestamp": "2026-02-06T14:45:00Z",
      "actor": "Dr. Sarah Chen",
      "detail": "Resolved with clinical note"
    }
  ]
}