"""
Compliance Reporting System
HIPAA/GDPR compliance reporting and audit trail management

Features:
- HIPAA audit trail reports
- GDPR compliance documentation
- Clinical quality metrics tracking
- Review queue performance analysis
- Security incident reporting
- Regulatory compliance dashboards

Author: MiniMax Agent
Date: 2025-10-29
Version: 1.0.0
"""

import logging
from typing import Dict, List, Any, Optional
from datetime import datetime, timedelta
from collections import defaultdict
from dataclasses import dataclass, asdict
from enum import Enum

logger = logging.getLogger(__name__)


class ComplianceStandard(Enum):
    """Compliance standards"""
    HIPAA = "HIPAA"
    GDPR = "GDPR"
    FDA = "FDA"
    ISO13485 = "ISO13485"


@dataclass
class AuditEvent:
    """Audit trail event"""
    event_id: str
    timestamp: str
    user_id: str
    event_type: str
    resource: str
    action: str
    ip_address: str
    success: bool
    details: Dict[str, Any]
    
    def to_dict(self) -> Dict[str, Any]:
        return asdict(self)


@dataclass
class ComplianceMetric:
    """Compliance metric"""
    metric_name: str
    value: float
    target: float
    status: str  # "compliant", "warning", "non_compliant"
    timestamp: str
    
    def to_dict(self) -> Dict[str, Any]:
        return asdict(self)


class ComplianceReportingSystem:
    """
    Comprehensive compliance reporting system
    Generates reports for regulatory audits and quality assurance
    """
    
    def __init__(self):
        self.audit_trail: List[AuditEvent] = []
        self.compliance_metrics: Dict[str, List[ComplianceMetric]] = defaultdict(list)
        self.phi_access_log: List[Dict[str, Any]] = []
        self.security_incidents: List[Dict[str, Any]] = []
        
        logger.info("Compliance Reporting System initialized")
    
    def log_audit_event(
        self,
        user_id: str,
        event_type: str,
        resource: str,
        action: str,
        ip_address: str,
        success: bool = True,
        details: Optional[Dict[str, Any]] = None
    ) -> AuditEvent:
        """Log an audit event for compliance tracking"""
        
        event = AuditEvent(
            event_id=f"audit_{len(self.audit_trail)}_{datetime.utcnow().timestamp()}",
            timestamp=datetime.utcnow().isoformat(),
            user_id=user_id,
            event_type=event_type,
            resource=resource,
            action=action,
            ip_address=ip_address,
            success=success,
            details=details or {}
        )
        
        self.audit_trail.append(event)
        
        return event
    
    def log_phi_access(
        self,
        user_id: str,
        document_id: str,
        action: str,
        ip_address: str,
        timestamp: Optional[str] = None
    ):
        """Log PHI access (HIPAA requirement)"""
        
        access_log = {
            "timestamp": timestamp or datetime.utcnow().isoformat(),
            "user_id": user_id,
            "document_id": document_id,
            "action": action,
            "ip_address": ip_address
        }
        
        self.phi_access_log.append(access_log)
        
        # Also log as audit event
        self.log_audit_event(
            user_id=user_id,
            event_type="PHI_ACCESS",
            resource=f"document:{document_id}",
            action=action,
            ip_address=ip_address,
            details={"document_id": document_id}
        )
    
    def log_security_incident(
        self,
        incident_type: str,
        severity: str,
        description: str,
        user_id: Optional[str] = None,
        ip_address: Optional[str] = None,
        details: Optional[Dict[str, Any]] = None
    ):
        """Log security incident"""
        
        incident = {
            "timestamp": datetime.utcnow().isoformat(),
            "incident_type": incident_type,
            "severity": severity,
            "description": description,
            "user_id": user_id,
            "ip_address": ip_address,
            "details": details or {},
            "resolved": False
        }
        
        self.security_incidents.append(incident)
        
        logger.warning(f"Security incident logged: {incident_type} (severity: {severity})")
    
    def record_compliance_metric(
        self,
        metric_name: str,
        value: float,
        target: float
    ):
        """Record a compliance metric"""
        
        # Determine status
        if value >= target:
            status = "compliant"
        elif value >= target * 0.9:  # Within 10% of target
            status = "warning"
        else:
            status = "non_compliant"
        
        metric = ComplianceMetric(
            metric_name=metric_name,
            value=value,
            target=target,
            status=status,
            timestamp=datetime.utcnow().isoformat()
        )
        
        self.compliance_metrics[metric_name].append(metric)
    
    def generate_hipaa_report(
        self,
        start_date: Optional[datetime] = None,
        end_date: Optional[datetime] = None
    ) -> Dict[str, Any]:
        """Generate HIPAA compliance report"""
        
        if not start_date:
            start_date = datetime.utcnow() - timedelta(days=30)
        if not end_date:
            end_date = datetime.utcnow()
        
        # Filter PHI access logs
        phi_accesses = [
            log for log in self.phi_access_log
            if start_date <= datetime.fromisoformat(log["timestamp"]) <= end_date
        ]
        
        # Aggregate by user
        access_by_user = defaultdict(int)
        for access in phi_accesses:
            access_by_user[access["user_id"]] += 1
        
        # Aggregate by action
        access_by_action = defaultdict(int)
        for access in phi_accesses:
            access_by_action[access["action"]] += 1
        
        report = {
            "report_type": "HIPAA_COMPLIANCE",
            "period": {
                "start": start_date.isoformat(),
                "end": end_date.isoformat()
            },
            "generated_at": datetime.utcnow().isoformat(),
            "summary": {
                "total_phi_accesses": len(phi_accesses),
                "unique_users": len(access_by_user),
                "access_by_user": dict(access_by_user),
                "access_by_action": dict(access_by_action)
            },
            "audit_trail_summary": {
                "total_events": len([
                    e for e in self.audit_trail
                    if start_date <= datetime.fromisoformat(e.timestamp) <= end_date
                ]),
                "phi_access_events": len(phi_accesses)
            },
            "security_incidents": len([
                i for i in self.security_incidents
                if start_date <= datetime.fromisoformat(i["timestamp"]) <= end_date
            ]),
            "compliance_status": "COMPLIANT" if len(self.security_incidents) == 0 else "REVIEW_REQUIRED"
        }
        
        return report
    
    def generate_gdpr_report(
        self,
        start_date: Optional[datetime] = None,
        end_date: Optional[datetime] = None
    ) -> Dict[str, Any]:
        """Generate GDPR compliance report"""
        
        if not start_date:
            start_date = datetime.utcnow() - timedelta(days=30)
        if not end_date:
            end_date = datetime.utcnow()
        
        # Filter relevant audit events
        audit_events = [
            e for e in self.audit_trail
            if start_date <= datetime.fromisoformat(e.timestamp) <= end_date
        ]
        
        # Count data processing activities
        data_processing_events = [
            e for e in audit_events
            if e.event_type in ["UPLOAD", "PROCESS", "DELETE"]
        ]
        
        # Count access events
        access_events = [
            e for e in audit_events
            if e.event_type in ["VIEW", "DOWNLOAD", "PHI_ACCESS"]
        ]
        
        report = {
            "report_type": "GDPR_COMPLIANCE",
            "period": {
                "start": start_date.isoformat(),
                "end": end_date.isoformat()
            },
            "generated_at": datetime.utcnow().isoformat(),
            "data_processing": {
                "total_processing_events": len(data_processing_events),
                "by_action": self._count_by_field(data_processing_events, "action")
            },
            "data_access": {
                "total_access_events": len(access_events),
                "by_user": self._count_by_field(access_events, "user_id")
            },
            "data_retention": {
                "retention_policy_days": 2555,  # 7 years for medical records
                "current_records": len(self.phi_access_log),
                "oldest_record": min(
                    [log["timestamp"] for log in self.phi_access_log],
                    default=None
                )
            },
            "user_rights": {
                "access_requests": 0,  # Would track actual requests
                "deletion_requests": 0,
                "portability_requests": 0
            },
            "compliance_status": "COMPLIANT"
        }
        
        return report
    
    def generate_quality_metrics_report(
        self,
        window_days: int = 30
    ) -> Dict[str, Any]:
        """Generate clinical quality metrics report"""
        
        cutoff = datetime.utcnow() - timedelta(days=window_days)
        
        # Get recent metrics
        recent_metrics = {}
        for metric_name, metrics_list in self.compliance_metrics.items():
            recent = [
                m for m in metrics_list
                if datetime.fromisoformat(m.timestamp) > cutoff
            ]
            
            if recent:
                latest = recent[-1]
                recent_metrics[metric_name] = {
                    "current_value": latest.value,
                    "target": latest.target,
                    "status": latest.status,
                    "trend": self._calculate_trend(recent)
                }
        
        report = {
            "report_type": "QUALITY_METRICS",
            "period_days": window_days,
            "generated_at": datetime.utcnow().isoformat(),
            "metrics": recent_metrics,
            "overall_compliance_rate": self._calculate_overall_compliance(),
            "non_compliant_metrics": [
                name for name, data in recent_metrics.items()
                if data["status"] == "non_compliant"
            ]
        }
        
        return report
    
    def generate_review_queue_report(
        self,
        window_days: int = 30
    ) -> Dict[str, Any]:
        """Generate review queue performance report"""
        
        cutoff = datetime.utcnow() - timedelta(days=window_days)
        
        # Filter review events from audit trail
        review_events = [
            e for e in self.audit_trail
            if e.event_type == "REVIEW" and
            datetime.fromisoformat(e.timestamp) > cutoff
        ]
        
        # Calculate metrics
        total_reviews = len(review_events)
        reviews_by_user = self._count_by_field(review_events, "user_id")
        
        # Calculate average turnaround time (would need actual data)
        avg_turnaround_hours = 24.0  # Placeholder
        
        report = {
            "report_type": "REVIEW_QUEUE_PERFORMANCE",
            "period_days": window_days,
            "generated_at": datetime.utcnow().isoformat(),
            "summary": {
                "total_reviews": total_reviews,
                "average_turnaround_hours": avg_turnaround_hours,
                "reviews_by_reviewer": reviews_by_user
            },
            "performance_metrics": {
                "reviews_per_day": total_reviews / window_days,
                "target_turnaround_hours": 24.0,
                "turnaround_compliance": "COMPLIANT" if avg_turnaround_hours <= 24 else "NON_COMPLIANT"
            }
        }
        
        return report
    
    def generate_security_incidents_report(
        self,
        window_days: int = 30
    ) -> Dict[str, Any]:
        """Generate security incidents report"""
        
        cutoff = datetime.utcnow() - timedelta(days=window_days)
        
        recent_incidents = [
            i for i in self.security_incidents
            if datetime.fromisoformat(i["timestamp"]) > cutoff
        ]
        
        by_severity = self._count_by_field(recent_incidents, "severity")
        by_type = self._count_by_field(recent_incidents, "incident_type")
        
        unresolved = [i for i in recent_incidents if not i.get("resolved", False)]
        
        report = {
            "report_type": "SECURITY_INCIDENTS",
            "period_days": window_days,
            "generated_at": datetime.utcnow().isoformat(),
            "summary": {
                "total_incidents": len(recent_incidents),
                "unresolved_incidents": len(unresolved),
                "by_severity": by_severity,
                "by_type": by_type
            },
            "critical_incidents": [
                i for i in recent_incidents
                if i["severity"] == "high"
            ],
            "compliance_impact": "CRITICAL" if len(unresolved) > 0 and any(
                i["severity"] == "high" for i in unresolved
            ) else "ACCEPTABLE"
        }
        
        return report
    
    def get_compliance_dashboard(self) -> Dict[str, Any]:
        """Get comprehensive compliance dashboard data"""
        
        return {
            "timestamp": datetime.utcnow().isoformat(),
            "hipaa_status": self._get_hipaa_status(),
            "gdpr_status": self._get_gdpr_status(),
            "quality_metrics": self._get_quality_status(),
            "security_status": self._get_security_status(),
            "audit_trail": {
                "total_events": len(self.audit_trail),
                "phi_accesses": len(self.phi_access_log),
                "recent_events": len([
                    e for e in self.audit_trail
                    if datetime.fromisoformat(e.timestamp) > datetime.utcnow() - timedelta(hours=24)
                ])
            }
        }
    
    def _count_by_field(self, items: List[Any], field: str) -> Dict[str, int]:
        """Count items by a specific field"""
        counts = defaultdict(int)
        for item in items:
            if isinstance(item, dict):
                value = item.get(field, "unknown")
            else:
                value = getattr(item, field, "unknown")
            counts[value] += 1
        return dict(counts)
    
    def _calculate_trend(self, metrics: List[ComplianceMetric]) -> str:
        """Calculate trend from metrics"""
        if len(metrics) < 2:
            return "stable"
        
        recent_value = metrics[-1].value
        previous_value = metrics[-2].value
        
        change_percent = (recent_value - previous_value) / previous_value if previous_value > 0 else 0
        
        if change_percent > 0.05:
            return "improving"
        elif change_percent < -0.05:
            return "declining"
        else:
            return "stable"
    
    def _calculate_overall_compliance(self) -> float:
        """Calculate overall compliance rate"""
        all_metrics = []
        for metrics_list in self.compliance_metrics.values():
            if metrics_list:
                all_metrics.append(metrics_list[-1])
        
        if not all_metrics:
            return 1.0
        
        compliant = sum(1 for m in all_metrics if m.status == "compliant")
        return compliant / len(all_metrics)
    
    def _get_hipaa_status(self) -> str:
        """Get HIPAA compliance status"""
        if len(self.security_incidents) > 0:
            return "REVIEW_REQUIRED"
        return "COMPLIANT"
    
    def _get_gdpr_status(self) -> str:
        """Get GDPR compliance status"""
        # Check if audit trail is complete
        if len(self.audit_trail) == 0:
            return "NOT_CONFIGURED"
        return "COMPLIANT"
    
    def _get_quality_status(self) -> str:
        """Get quality metrics status"""
        compliance_rate = self._calculate_overall_compliance()
        
        if compliance_rate >= 0.95:
            return "EXCELLENT"
        elif compliance_rate >= 0.85:
            return "GOOD"
        elif compliance_rate >= 0.75:
            return "ACCEPTABLE"
        else:
            return "NEEDS_IMPROVEMENT"
    
    def _get_security_status(self) -> str:
        """Get security status"""
        recent_incidents = [
            i for i in self.security_incidents
            if datetime.fromisoformat(i["timestamp"]) > datetime.utcnow() - timedelta(days=7)
        ]
        
        if any(i["severity"] == "high" for i in recent_incidents):
            return "CRITICAL"
        elif len(recent_incidents) > 0:
            return "WARNING"
        else:
            return "SECURE"


# Global instance
_compliance_system = None


def get_compliance_system() -> ComplianceReportingSystem:
    """Get singleton compliance system instance"""
    global _compliance_system
    if _compliance_system is None:
        _compliance_system = ComplianceReportingSystem()
    return _compliance_system