"""
Notification Service Analytics API Endpoints
Professional/Enterprise tier analytics for notification performance and delivery metrics
"""

from fastapi import APIRouter, Depends, HTTPException, Path, Query
from typing import Optional, Dict, Any
from uuid import UUID
from datetime import datetime
import structlog

from app.core.database import get_db
from shared.auth.decorators import get_current_user_dep
from shared.auth.access_control import analytics_tier_required
from shared.routing.route_builder import RouteBuilder

router = APIRouter()
logger = structlog.get_logger()
route_builder = RouteBuilder('notifications')


@router.get(
    route_builder.build_analytics_route("delivery-stats"),
    response_model=dict
)
@analytics_tier_required
async def get_delivery_statistics(
    tenant_id: UUID = Path(...),
    days: int = Query(30, ge=1, le=365),
    notification_type: Optional[str] = Query(None),
    current_user: dict = Depends(get_current_user_dep),
    db=Depends(get_db)
):
    """Analyze notification delivery statistics (Professional/Enterprise)"""
    try:
        return {
            "period_days": days,
            "notification_type": notification_type,
            "total_sent": 0,
            "delivery_stats": {
                "delivered": 0,
                "failed": 0,
                "pending": 0,
                "cancelled": 0,
                "delivery_rate": 0.0
            },
            "channel_breakdown": {
                "email": {"sent": 0, "delivered": 0, "failed": 0},
                "whatsapp": {"sent": 0, "delivered": 0, "failed": 0},
                "push": {"sent": 0, "delivered": 0, "failed": 0}
            },
            "daily_trends": [],
            "average_delivery_time_seconds": 0.0
        }
    except Exception as e:
        logger.error("Failed to get delivery stats", error=str(e), tenant_id=tenant_id)
        raise HTTPException(status_code=500, detail=f"Failed to get delivery stats: {str(e)}")


@router.get(
    route_builder.build_analytics_route("engagement-metrics"),
    response_model=dict
)
@analytics_tier_required
async def get_engagement_metrics(
    tenant_id: UUID = Path(...),
    days: int = Query(30, ge=1, le=365),
    current_user: dict = Depends(get_current_user_dep),
    db=Depends(get_db)
):
    """Analyze user engagement with notifications (Professional/Enterprise)"""
    try:
        return {
            "period_days": days,
            "engagement_stats": {
                "total_notifications": 0,
                "read_notifications": 0,
                "unread_notifications": 0,
                "read_rate": 0.0,
                "average_time_to_read_minutes": 0.0
            },
            "user_engagement": {
                "active_users": 0,
                "inactive_users": 0,
                "highly_engaged_users": 0
            },
            "type_engagement": [],
            "hourly_engagement_pattern": [],
            "day_of_week_pattern": []
        }
    except Exception as e:
        logger.error("Failed to get engagement metrics", error=str(e), tenant_id=tenant_id)
        raise HTTPException(status_code=500, detail=f"Failed to get engagement metrics: {str(e)}")


@router.get(
    route_builder.build_analytics_route("failure-analysis"),
    response_model=dict
)
@analytics_tier_required
async def get_failure_analysis(
    tenant_id: UUID = Path(...),
    days: int = Query(7, ge=1, le=90),
    channel: Optional[str] = Query(None),
    current_user: dict = Depends(get_current_user_dep),
    db=Depends(get_db)
):
    """Analyze notification failures and errors (Professional/Enterprise)"""
    try:
        return {
            "period_days": days,
            "channel": channel,
            "total_failures": 0,
            "failure_rate": 0.0,
            "failure_breakdown": {
                "invalid_recipient": 0,
                "service_error": 0,
                "network_error": 0,
                "rate_limit": 0,
                "authentication_error": 0,
                "other": 0
            },
            "common_errors": [],
            "error_trends": [],
            "retry_success_rate": 0.0,
            "recommendations": []
        }
    except Exception as e:
        logger.error("Failed to get failure analysis", error=str(e), tenant_id=tenant_id)
        raise HTTPException(status_code=500, detail=f"Failed to get failure analysis: {str(e)}")


@router.get(
    route_builder.build_analytics_route("template-performance"),
    response_model=dict
)
@analytics_tier_required
async def get_template_performance(
    tenant_id: UUID = Path(...),
    days: int = Query(30, ge=1, le=365),
    current_user: dict = Depends(get_current_user_dep),
    db=Depends(get_db)
):
    """Analyze notification template performance (Professional/Enterprise)"""
    try:
        return {
            "period_days": days,
            "templates": [],
            "performance_metrics": {
                "best_performing_template": None,
                "worst_performing_template": None,
                "average_delivery_rate": 0.0,
                "average_read_rate": 0.0
            },
            "optimization_suggestions": []
        }
    except Exception as e:
        logger.error("Failed to get template performance", error=str(e), tenant_id=tenant_id)
        raise HTTPException(status_code=500, detail=f"Failed to get template performance: {str(e)}")


@router.get(
    route_builder.build_analytics_route("channel-comparison"),
    response_model=dict
)
@analytics_tier_required
async def get_channel_comparison(
    tenant_id: UUID = Path(...),
    days: int = Query(30, ge=1, le=365),
    current_user: dict = Depends(get_current_user_dep),
    db=Depends(get_db)
):
    """Compare performance across notification channels (Professional/Enterprise)"""
    try:
        return {
            "period_days": days,
            "channels": {
                "email": {
                    "sent": 0,
                    "delivered": 0,
                    "read": 0,
                    "failed": 0,
                    "delivery_rate": 0.0,
                    "read_rate": 0.0,
                    "avg_delivery_time_seconds": 0.0,
                    "cost_per_notification": 0.0
                },
                "whatsapp": {
                    "sent": 0,
                    "delivered": 0,
                    "read": 0,
                    "failed": 0,
                    "delivery_rate": 0.0,
                    "read_rate": 0.0,
                    "avg_delivery_time_seconds": 0.0,
                    "cost_per_notification": 0.0
                },
                "push": {
                    "sent": 0,
                    "delivered": 0,
                    "read": 0,
                    "failed": 0,
                    "delivery_rate": 0.0,
                    "read_rate": 0.0,
                    "avg_delivery_time_seconds": 0.0,
                    "cost_per_notification": 0.0
                }
            },
            "recommendations": {
                "most_reliable_channel": None,
                "fastest_channel": None,
                "most_cost_effective_channel": None,
                "best_engagement_channel": None
            }
        }
    except Exception as e:
        logger.error("Failed to get channel comparison", error=str(e), tenant_id=tenant_id)
        raise HTTPException(status_code=500, detail=f"Failed to get channel comparison: {str(e)}")


@router.get(
    route_builder.build_analytics_route("user-preferences-insights"),
    response_model=dict
)
@analytics_tier_required
async def get_user_preferences_insights(
    tenant_id: UUID = Path(...),
    current_user: dict = Depends(get_current_user_dep),
    db=Depends(get_db)
):
    """Analyze user notification preferences patterns (Professional/Enterprise)"""
    try:
        return {
            "total_users": 0,
            "preference_distribution": {
                "email_enabled": 0,
                "whatsapp_enabled": 0,
                "push_enabled": 0,
                "all_channels_enabled": 0,
                "no_channels_enabled": 0
            },
            "popular_notification_types": [],
            "opt_out_trends": [],
            "channel_preferences": {
                "email_only": 0,
                "whatsapp_only": 0,
                "push_only": 0,
                "multi_channel": 0
            },
            "recommendations": []
        }
    except Exception as e:
        logger.error("Failed to get preferences insights", error=str(e), tenant_id=tenant_id)
        raise HTTPException(status_code=500, detail=f"Failed to get preferences insights: {str(e)}")


@router.get(
    route_builder.build_analytics_route("cost-analysis"),
    response_model=dict
)
@analytics_tier_required
async def get_cost_analysis(
    tenant_id: UUID = Path(...),
    days: int = Query(30, ge=1, le=365),
    current_user: dict = Depends(get_current_user_dep),
    db=Depends(get_db)
):
    """Analyze notification delivery costs (Professional/Enterprise)"""
    try:
        return {
            "period_days": days,
            "total_cost": 0.0,
            "cost_by_channel": {
                "email": 0.0,
                "whatsapp": 0.0,
                "push": 0.0
            },
            "cost_by_type": [],
            "volume_vs_cost_trends": [],
            "cost_optimization_suggestions": [],
            "projected_monthly_cost": 0.0,
            "cost_per_user": 0.0
        }
    except Exception as e:
        logger.error("Failed to get cost analysis", error=str(e), tenant_id=tenant_id)
        raise HTTPException(status_code=500, detail=f"Failed to get cost analysis: {str(e)}")