"""
Tool_OCR - Admin Router
Administrative endpoints for system management
"""

import logging
from typing import Optional
from datetime import datetime

from fastapi import APIRouter, Depends, HTTPException, status, Query
from sqlalchemy.orm import Session

from app.core.deps import get_db, get_current_admin_user
from app.models.user import User
from app.services.admin_service import admin_service
from app.services.audit_service import audit_service

logger = logging.getLogger(__name__)

router = APIRouter(prefix="/api/v2/admin", tags=["Admin"])


@router.get("/stats", summary="Get system statistics")
async def get_system_stats(
    db: Session = Depends(get_db),
    admin_user: User = Depends(get_current_admin_user)
):
    """
    Get overall system statistics

    Requires admin privileges
    """
    try:
        stats = admin_service.get_system_statistics(db)
        return stats

    except Exception as e:
        logger.exception("Failed to get system stats")
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail=f"Failed to get system stats: {str(e)}"
        )


@router.get("/users", summary="List all users")
async def list_users(
    page: int = Query(1, ge=1),
    page_size: int = Query(50, ge=1, le=100),
    db: Session = Depends(get_db),
    admin_user: User = Depends(get_current_admin_user)
):
    """
    Get list of all users with statistics

    Requires admin privileges
    """
    try:
        skip = (page - 1) * page_size
        users, total = admin_service.get_user_list(db, skip=skip, limit=page_size)

        return {
            "users": users,
            "total": total,
            "page": page,
            "page_size": page_size,
            "has_more": (skip + len(users)) < total
        }

    except Exception as e:
        logger.exception("Failed to list users")
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail=f"Failed to list users: {str(e)}"
        )


@router.get("/users/top", summary="Get top users")
async def get_top_users(
    metric: str = Query("tasks", regex="^(tasks|completed_tasks)$"),
    limit: int = Query(10, ge=1, le=50),
    db: Session = Depends(get_db),
    admin_user: User = Depends(get_current_admin_user)
):
    """
    Get top users by metric

    - **metric**: Ranking metric (tasks or completed_tasks)
    - **limit**: Number of users to return

    Requires admin privileges
    """
    try:
        top_users = admin_service.get_top_users(db, metric=metric, limit=limit)
        return top_users

    except Exception as e:
        logger.exception("Failed to get top users")
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail=f"Failed to get top users: {str(e)}"
        )


@router.get("/audit-logs", summary="Get audit logs")
async def get_audit_logs(
    user_id: Optional[int] = Query(None),
    event_category: Optional[str] = Query(None),
    event_type: Optional[str] = Query(None),
    date_from: Optional[str] = Query(None),
    date_to: Optional[str] = Query(None),
    success_only: Optional[bool] = Query(None),
    page: int = Query(1, ge=1),
    page_size: int = Query(100, ge=1, le=500),
    db: Session = Depends(get_db),
    admin_user: User = Depends(get_current_admin_user)
):
    """
    Get audit logs with filtering

    - **user_id**: Filter by user ID (optional)
    - **event_category**: Filter by category (authentication, task, admin, system)
    - **event_type**: Filter by event type (optional)
    - **date_from**: Filter from date (YYYY-MM-DD, optional)
    - **date_to**: Filter to date (YYYY-MM-DD, optional)
    - **success_only**: Filter by success status (optional)

    Requires admin privileges
    """
    try:
        # Parse dates
        date_from_dt = datetime.fromisoformat(date_from) if date_from else None
        date_to_dt = datetime.fromisoformat(date_to) if date_to else None

        skip = (page - 1) * page_size

        logs, total = audit_service.get_logs(
            db=db,
            user_id=user_id,
            event_category=event_category,
            event_type=event_type,
            date_from=date_from_dt,
            date_to=date_to_dt,
            success_only=success_only,
            skip=skip,
            limit=page_size
        )

        return {
            "logs": [log.to_dict() for log in logs],
            "total": total,
            "page": page,
            "page_size": page_size,
            "has_more": (skip + len(logs)) < total
        }

    except Exception as e:
        logger.exception("Failed to get audit logs")
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail=f"Failed to get audit logs: {str(e)}"
        )


@router.get("/audit-logs/user/{user_id}/summary", summary="Get user activity summary")
async def get_user_activity_summary(
    user_id: int,
    days: int = Query(30, ge=1, le=365),
    db: Session = Depends(get_db),
    admin_user: User = Depends(get_current_admin_user)
):
    """
    Get user activity summary for the last N days

    - **user_id**: User ID
    - **days**: Number of days to look back (default: 30)

    Requires admin privileges
    """
    try:
        summary = audit_service.get_user_activity_summary(db, user_id=user_id, days=days)
        return summary

    except Exception as e:
        logger.exception(f"Failed to get activity summary for user {user_id}")
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail=f"Failed to get user activity summary: {str(e)}"
        )