from fastapi import APIRouter, Depends, Query
from typing import Optional
from datetime import datetime

from app.core.auth import get_current_active_user, User
from app.core.database import get_database
from app.services.monitoring_service import MonitoringService

router = APIRouter()


def get_monitoring_service(db=Depends(get_database)) -> MonitoringService:
    """Dependency to get monitoring service"""
    return MonitoringService(db)


@router.get("/health")
async def get_system_health(
    current_user: User = Depends(get_current_active_user),
    monitoring_service: MonitoringService = Depends(get_monitoring_service)
):
    """
    Get overall system health status

    Includes MongoDB, pipelines, and other component health checks
    """
    health = await monitoring_service.get_system_health()
    return health


@router.get("/metrics")
async def get_system_metrics(
    current_user: User = Depends(get_current_active_user),
    monitoring_service: MonitoringService = Depends(get_monitoring_service)
):
    """
    Get system-wide metrics

    Includes counts and aggregations for keywords, pipelines, users, and applications
    """
    metrics = await monitoring_service.get_system_metrics()
    return metrics


@router.get("/logs")
async def get_activity_logs(
    limit: int = Query(100, ge=1, le=1000, description="Maximum number of logs"),
    level: Optional[str] = Query(None, description="Filter by log level (INFO, WARNING, ERROR)"),
    start_date: Optional[datetime] = Query(None, description="Filter logs after this date"),
    end_date: Optional[datetime] = Query(None, description="Filter logs before this date"),
    current_user: User = Depends(get_current_active_user),
    monitoring_service: MonitoringService = Depends(get_monitoring_service)
):
    """
    Get activity logs

    Returns logs from all pipelines with optional filtering
    """
    logs = await monitoring_service.get_activity_logs(
        limit=limit,
        level=level,
        start_date=start_date,
        end_date=end_date
    )
    return {"logs": logs, "total": len(logs)}


@router.get("/database/stats")
async def get_database_stats(
    current_user: User = Depends(get_current_active_user),
    monitoring_service: MonitoringService = Depends(get_monitoring_service)
):
    """
    Get MongoDB database statistics (admin only)

    Includes database size, collections, indexes, etc.
    """
    if current_user.role != "admin":
        from fastapi import HTTPException, status
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail="Only admins can view database statistics"
        )

    stats = await monitoring_service.get_database_stats()
    return stats


@router.get("/database/collections")
async def get_collection_stats(
    current_user: User = Depends(get_current_active_user),
    monitoring_service: MonitoringService = Depends(get_monitoring_service)
):
    """
    Get statistics for all collections (admin only)

    Includes document counts, sizes, and index information
    """
    if current_user.role != "admin":
        from fastapi import HTTPException, status
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail="Only admins can view collection statistics"
        )

    collections = await monitoring_service.get_collection_stats()
    return {"collections": collections, "total": len(collections)}


@router.get("/pipelines/performance")
async def get_pipeline_performance(
    hours: int = Query(24, ge=1, le=168, description="Number of hours to look back"),
    current_user: User = Depends(get_current_active_user),
    monitoring_service: MonitoringService = Depends(get_monitoring_service)
):
    """
    Get pipeline performance metrics

    Shows success rates, error counts, and activity for each pipeline
    """
    performance = await monitoring_service.get_pipeline_performance(hours=hours)
    return performance


@router.get("/errors/summary")
async def get_error_summary(
    hours: int = Query(24, ge=1, le=168, description="Number of hours to look back"),
    current_user: User = Depends(get_current_active_user),
    monitoring_service: MonitoringService = Depends(get_monitoring_service)
):
    """
    Get summary of recent errors

    Shows error counts and recent error details
    """
    summary = await monitoring_service.get_error_summary(hours=hours)
    return summary