"""
Analytics API endpoints for usage metrics, cost analysis, and system health
Integrated with the core analytics service for comprehensive tracking.
"""
from typing import Optional, Dict, Any
from fastapi import APIRouter, Depends, HTTPException, Query
from sqlalchemy.orm import Session

from app.core.security import get_current_user
from app.db.database import get_db
from app.models.user import User
from app.services.analytics import get_analytics_service
from app.services.module_manager import module_manager
from app.core.logging import get_logger

logger = get_logger(__name__)

router = APIRouter()


@router.get("/metrics")
async def get_usage_metrics(
    hours: int = Query(24, ge=1, le=168, description="Hours to analyze (1-168)"),
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    """Get comprehensive usage metrics including costs and budgets"""
    try:
        analytics = get_analytics_service()
        metrics = await analytics.get_usage_metrics(hours=hours, user_id=current_user['id'])
        return {
            "success": True,
            "data": metrics,
            "period_hours": hours
        }
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error getting usage metrics: {str(e)}")


@router.get("/metrics/system")
async def get_system_metrics(
    hours: int = Query(24, ge=1, le=168),
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    """Get system-wide metrics (admin only)"""
    if not current_user['is_superuser']:
        raise HTTPException(status_code=403, detail="Admin access required")
    
    try:
        analytics = get_analytics_service()
        metrics = await analytics.get_usage_metrics(hours=hours)
        return {
            "success": True,
            "data": metrics,
            "period_hours": hours
        }
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error getting system metrics: {str(e)}")


@router.get("/health")
async def get_system_health(
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    """Get system health status including budget and performance analysis"""
    try:
        analytics = get_analytics_service()
        health = await analytics.get_system_health()
        return {
            "success": True,
            "data": health
        }
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error getting system health: {str(e)}")


@router.get("/costs")
async def get_cost_analysis(
    days: int = Query(30, ge=1, le=365, description="Days to analyze (1-365)"),
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    """Get detailed cost analysis and trends"""
    try:
        analytics = get_analytics_service()
        analysis = await analytics.get_cost_analysis(days=days, user_id=current_user['id'])
        return {
            "success": True,
            "data": analysis,
            "period_days": days
        }
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error getting cost analysis: {str(e)}")


@router.get("/costs/system")
async def get_system_cost_analysis(
    days: int = Query(30, ge=1, le=365),
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    """Get system-wide cost analysis (admin only)"""
    if not current_user['is_superuser']:
        raise HTTPException(status_code=403, detail="Admin access required")
    
    try:
        analytics = get_analytics_service()
        analysis = await analytics.get_cost_analysis(days=days)
        return {
            "success": True,
            "data": analysis,
            "period_days": days
        }
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error getting system cost analysis: {str(e)}")


@router.get("/endpoints")
async def get_endpoint_stats(
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    """Get endpoint usage statistics"""
    try:
        analytics = get_analytics_service()
        
        # For now, return the in-memory stats
        # In future, this could be enhanced with database queries
        return {
            "success": True,
            "data": {
                "endpoint_stats": dict(analytics.endpoint_stats),
                "status_codes": dict(analytics.status_codes),
                "model_stats": dict(analytics.model_stats)
            }
        }
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error getting endpoint stats: {str(e)}")


@router.get("/usage-trends")
async def get_usage_trends(
    days: int = Query(7, ge=1, le=30, description="Days for trend analysis"),
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    """Get usage trends over time"""
    try:
        from datetime import datetime, timedelta
        from sqlalchemy import func
        from app.models.usage_tracking import UsageTracking
        
        cutoff_time = datetime.utcnow() - timedelta(days=days)
        
        # Daily usage trends
        daily_usage = db.query(
            func.date(UsageTracking.created_at).label('date'),
            func.count(UsageTracking.id).label('requests'),
            func.sum(UsageTracking.total_tokens).label('tokens'),
            func.sum(UsageTracking.cost_cents).label('cost_cents')
        ).filter(
            UsageTracking.created_at >= cutoff_time,
            UsageTracking.user_id == current_user['id']
        ).group_by(
            func.date(UsageTracking.created_at)
        ).order_by('date').all()
        
        trends = []
        for date, requests, tokens, cost_cents in daily_usage:
            trends.append({
                "date": date.isoformat(),
                "requests": requests,
                "tokens": tokens or 0,
                "cost_cents": cost_cents or 0,
                "cost_dollars": (cost_cents or 0) / 100
            })
        
        return {
            "success": True,
            "data": {
                "trends": trends,
                "period_days": days
            }
        }
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error getting usage trends: {str(e)}")


@router.get("/overview")
async def get_analytics_overview(
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    """Get analytics overview data"""
    try:
        analytics = get_analytics_service()
        
        # Get basic metrics
        metrics = await analytics.get_usage_metrics(hours=24, user_id=current_user['id'])
        health = await analytics.get_system_health()
        
        return {
            "success": True,
            "data": {
                "total_requests": metrics.total_requests,
                "total_cost_dollars": metrics.total_cost_cents / 100,
                "avg_response_time": metrics.avg_response_time,
                "error_rate": metrics.error_rate,
                "budget_usage_percentage": metrics.budget_usage_percentage,
                "system_health": health.status,
                "health_score": health.score
            }
        }
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error getting overview: {str(e)}")


@router.get("/modules")
async def get_module_analytics(
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    """Get analytics data for all modules"""
    try:
        module_stats = []
        
        for name, module in module_manager.modules.items():
            stats = {"name": name, "initialized": getattr(module, "initialized", False)}
            
            # Get module statistics if available
            if hasattr(module, "get_stats"):
                try:
                    module_data = module.get_stats()
                    if hasattr(module_data, "__dict__"):
                        stats.update(module_data.__dict__)
                    elif isinstance(module_data, dict):
                        stats.update(module_data)
                except Exception as e:
                    logger.warning(f"Failed to get stats for module {name}: {e}")
                    stats["error"] = str(e)
            
            module_stats.append(stats)
        
        return {
            "success": True,
            "data": {
                "modules": module_stats,
                "total_modules": len(module_stats),
                "system_health": "healthy" if all(m.get("initialized", False) for m in module_stats) else "warning"
            }
        }
        
    except Exception as e:
        logger.error(f"Failed to get module analytics: {e}")
        raise HTTPException(status_code=500, detail="Failed to retrieve module analytics")