"""
Comprehensive Admin API endpoints - User management, system settings, audit logging
"""
from typing import List, Dict, Any, Optional
from fastapi import APIRouter, Depends, HTTPException, status, UploadFile, File, Query, Body, Request
from fastapi.responses import FileResponse
from sqlalchemy.orm import Session, joinedload
from sqlalchemy import func, text, desc, asc, and_, or_
import csv
import io
import os
import hashlib
import secrets
import shutil
import time
from datetime import datetime, timedelta, date
from pathlib import Path

from app.database.base import get_db
from app.models import User, Rolodex, File as FileModel, Ledger, QDRO, AuditLog, LoginAttempt
from app.models.lookups import SystemSetup, Employee, FileType, FileStatus, TransactionType, TransactionCode, State, FormIndex
from app.auth.security import get_admin_user, get_password_hash, create_access_token
from app.services.audit import audit_service
from app.config import settings

router = APIRouter()


# Enhanced Admin Schemas
from pydantic import BaseModel, Field, EmailStr

class SystemStats(BaseModel):
    """Enhanced system statistics"""
    total_customers: int
    total_files: int
    total_transactions: int
    total_qdros: int
    total_users: int
    total_active_users: int
    total_admins: int
    database_size: str
    last_backup: str
    system_uptime: str
    recent_activity: List[Dict[str, Any]]

class HealthCheck(BaseModel):
    """Comprehensive system health check"""
    status: str
    database_connected: bool
    disk_space_available: bool
    memory_available: bool
    version: str
    uptime: str
    last_backup: Optional[str]
    active_sessions: int
    cpu_usage: float
    alerts: List[str]

class UserCreate(BaseModel):
    """Create new user"""
    username: str = Field(..., min_length=3, max_length=50)
    email: EmailStr
    password: str = Field(..., min_length=6)
    first_name: Optional[str] = None
    last_name: Optional[str] = None
    is_admin: bool = False
    is_active: bool = True

class UserUpdate(BaseModel):
    """Update user information"""
    username: Optional[str] = Field(None, min_length=3, max_length=50)
    email: Optional[EmailStr] = None
    first_name: Optional[str] = None
    last_name: Optional[str] = None
    is_admin: Optional[bool] = None
    is_active: Optional[bool] = None

class UserResponse(BaseModel):
    """User response model"""
    id: int
    username: str
    email: str
    first_name: Optional[str]
    last_name: Optional[str]
    is_admin: bool
    is_active: bool
    last_login: Optional[datetime]
    created_at: Optional[datetime]
    updated_at: Optional[datetime]
    
    class Config:
        from_attributes = True

class PasswordReset(BaseModel):
    """Password reset request"""
    new_password: str = Field(..., min_length=6)
    confirm_password: str = Field(..., min_length=6)

class SystemSetting(BaseModel):
    """System setting model"""
    setting_key: str
    setting_value: str
    description: Optional[str] = None
    setting_type: str = "STRING"

class SettingUpdate(BaseModel):
    """Update system setting"""
    setting_value: str
    description: Optional[str] = None

class AuditLogEntry(BaseModel):
    """Audit log entry"""
    id: int
    user_id: Optional[int]
    username: Optional[str]
    action: str
    resource_type: str
    resource_id: Optional[str]
    details: Optional[Dict[str, Any]]
    ip_address: Optional[str]
    user_agent: Optional[str]
    timestamp: datetime
    
    class Config:
        from_attributes = True

class BackupInfo(BaseModel):
    """Backup information"""
    filename: str
    size: str
    created_at: datetime
    backup_type: str
    status: str

class LookupTableInfo(BaseModel):
    """Lookup table information"""
    table_name: str
    display_name: str
    record_count: int
    last_updated: Optional[datetime]
    description: str

class DatabaseMaintenanceResult(BaseModel):
    """Database maintenance operation result"""
    operation: str
    status: str
    message: str
    duration_seconds: float
    records_affected: Optional[int] = None


# Enhanced Health and Statistics Endpoints

@router.get("/health", response_model=HealthCheck)
async def system_health(
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Comprehensive system health check"""
    alerts = []
    
    # Test database connection
    try:
        db.execute(text("SELECT 1"))
        db_connected = True
    except Exception as e:
        db_connected = False
        alerts.append(f"Database connection failed: {str(e)}")
    
    # Check disk space
    try:
        total, used, free = shutil.disk_usage(".")
        free_gb = free / (1024**3)
        disk_available = free_gb > 1.0  # 1GB minimum
        if not disk_available:
            alerts.append(f"Low disk space: {free_gb:.1f}GB remaining")
    except:
        disk_available = True
    
    # Check memory (simplified)
    try:
        import psutil
        memory = psutil.virtual_memory()
        memory_available = memory.percent < 90
        if not memory_available:
            alerts.append(f"High memory usage: {memory.percent:.1f}%")
    except ImportError:
        memory_available = True
    
    # Get CPU usage
    try:
        import psutil
        cpu_usage = psutil.cpu_percent(interval=1)
        if cpu_usage > 80:
            alerts.append(f"High CPU usage: {cpu_usage:.1f}%")
    except ImportError:
        cpu_usage = 0.0
    
    # Count active sessions (simplified)
    try:
        active_sessions = db.query(User).filter(
            User.last_login > datetime.now() - timedelta(hours=24)
        ).count()
    except:
        active_sessions = 0
    
    # Check last backup
    last_backup = None
    try:
        backup_dir = Path("backups")
        if backup_dir.exists():
            backup_files = list(backup_dir.glob("*.db"))
            if backup_files:
                latest_backup = max(backup_files, key=lambda p: p.stat().st_mtime)
                backup_age = datetime.now() - datetime.fromtimestamp(latest_backup.stat().st_mtime)
                last_backup = latest_backup.name
                if backup_age.days > 7:
                    alerts.append(f"Last backup is {backup_age.days} days old")
    except:
        alerts.append("Unable to check backup status")
    
    # System uptime (simplified)
    try:
        import psutil
        uptime_seconds = time.time() - psutil.boot_time()
        uptime = str(timedelta(seconds=int(uptime_seconds)))
    except ImportError:
        uptime = "Unknown"
    
    status = "healthy" if db_connected and disk_available and memory_available else "unhealthy"
    
    return HealthCheck(
        status=status,
        database_connected=db_connected,
        disk_space_available=disk_available,
        memory_available=memory_available,
        version=settings.app_version,
        uptime=uptime,
        last_backup=last_backup,
        active_sessions=active_sessions,
        cpu_usage=cpu_usage,
        alerts=alerts
    )


@router.get("/stats", response_model=SystemStats)
async def system_statistics(
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Enhanced system statistics with comprehensive metrics"""
    
    total_customers = db.query(func.count(Rolodex.id)).scalar()
    total_files = db.query(func.count(FileModel.file_no)).scalar()
    total_transactions = db.query(func.count(Ledger.id)).scalar()
    total_qdros = db.query(func.count(QDRO.id)).scalar()
    total_users = db.query(func.count(User.id)).scalar()
    
    # Count active users (logged in within last 30 days)
    total_active_users = db.query(func.count(User.id)).filter(
        User.last_login > datetime.now() - timedelta(days=30)
    ).scalar()
    
    # Count admin users
    total_admins = db.query(func.count(User.id)).filter(User.is_admin == True).scalar()
    
    # Database size (for SQLite)
    db_size = "Unknown"
    if "sqlite" in settings.database_url:
        try:
            db_path = settings.database_url.replace("sqlite:///", "")
            if os.path.exists(db_path):
                size_bytes = os.path.getsize(db_path)
                db_size = f"{size_bytes / (1024*1024):.1f} MB"
        except:
            pass
    
    # Check for recent backups
    last_backup = "Not found"
    try:
        backup_dir = Path("backups")
        if backup_dir.exists():
            backup_files = list(backup_dir.glob("*.db"))
            if backup_files:
                latest_backup = max(backup_files, key=lambda p: p.stat().st_mtime)
                last_backup = latest_backup.name
    except:
        pass
    
    # System uptime (simplified)
    system_uptime = "Unknown"
    try:
        import psutil
        uptime_seconds = time.time() - psutil.boot_time()
        system_uptime = str(timedelta(seconds=int(uptime_seconds)))
    except ImportError:
        pass
    
    # Recent activity (last 10 actions)
    recent_activity = []
    try:
        # Get recent files created
        recent_files = db.query(FileModel).order_by(desc(FileModel.opened)).limit(5).all()
        for file in recent_files:
            recent_activity.append({
                "type": "file_created",
                "description": f"File {file.file_no} created",
                "timestamp": file.opened.isoformat() if file.opened else None
            })
        
        # Get recent customer additions
        recent_customers = db.query(Rolodex).order_by(desc(Rolodex.id)).limit(5).all()
        for customer in recent_customers:
            recent_activity.append({
                "type": "customer_added",
                "description": f"Customer {customer.first} {customer.last} added",
                "timestamp": datetime.now().isoformat()
            })
    except:
        pass
    
    return SystemStats(
        total_customers=total_customers,
        total_files=total_files,
        total_transactions=total_transactions,
        total_qdros=total_qdros,
        total_users=total_users,
        total_active_users=total_active_users,
        total_admins=total_admins,
        database_size=db_size,
        last_backup=last_backup,
        system_uptime=system_uptime,
        recent_activity=recent_activity
    )


@router.post("/import/csv")
async def import_csv(
    table_name: str,
    file: UploadFile = File(...),
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Import data from CSV file"""
    
    if not file.filename.endswith('.csv'):
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="File must be a CSV"
        )
    
    # Read CSV content
    content = await file.read()
    csv_data = csv.DictReader(io.StringIO(content.decode('utf-8')))
    
    imported_count = 0
    errors = []
    
    try:
        if table_name.lower() == "customers" or table_name.lower() == "rolodex":
            for row_num, row in enumerate(csv_data, start=1):
                try:
                    customer = Rolodex(**row)
                    db.add(customer)
                    imported_count += 1
                except Exception as e:
                    errors.append(f"Row {row_num}: {str(e)}")
        
        elif table_name.lower() == "files":
            for row_num, row in enumerate(csv_data, start=1):
                try:
                    # Convert date strings to date objects if needed
                    if 'opened' in row and row['opened']:
                        row['opened'] = datetime.strptime(row['opened'], '%Y-%m-%d').date()
                    if 'closed' in row and row['closed']:
                        row['closed'] = datetime.strptime(row['closed'], '%Y-%m-%d').date()
                    
                    file_obj = FileModel(**row)
                    db.add(file_obj)
                    imported_count += 1
                except Exception as e:
                    errors.append(f"Row {row_num}: {str(e)}")
        
        else:
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail=f"Import not supported for table: {table_name}"
            )
        
        db.commit()
        
    except Exception as e:
        db.rollback()
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=f"Import failed: {str(e)}"
        )
    
    return {
        "message": f"Import completed",
        "imported_count": imported_count,
        "error_count": len(errors),
        "errors": errors[:10]  # Return first 10 errors
    }


@router.get("/export/{table_name}")
async def export_table(
    table_name: str,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Export table data to CSV"""
    
    # Create exports directory if it doesn't exist
    os.makedirs("exports", exist_ok=True)
    
    filename = f"exports/{table_name}_{datetime.now().strftime('%Y%m%d_%H%M%S')}.csv"
    
    try:
        if table_name.lower() == "customers" or table_name.lower() == "rolodex":
            customers = db.query(Rolodex).all()
            
            with open(filename, 'w', newline='', encoding='utf-8') as csvfile:
                if customers:
                    fieldnames = ['id', 'last', 'first', 'middle', 'prefix', 'suffix', 
                                'title', 'group', 'a1', 'a2', 'a3', 'city', 'abrev', 
                                'zip', 'email', 'dob', 'ss_number', 'legal_status', 'memo']
                    writer = csv.DictWriter(csvfile, fieldnames=fieldnames)
                    writer.writeheader()
                    
                    for customer in customers:
                        row = {field: getattr(customer, field) for field in fieldnames}
                        writer.writerow(row)
        
        elif table_name.lower() == "files":
            files = db.query(FileModel).all()
            
            with open(filename, 'w', newline='', encoding='utf-8') as csvfile:
                if files:
                    fieldnames = ['file_no', 'id', 'regarding', 'empl_num', 'file_type',
                                'opened', 'closed', 'status', 'footer_code', 'opposing',
                                'rate_per_hour', 'memo']
                    writer = csv.DictWriter(csvfile, fieldnames=fieldnames)
                    writer.writeheader()
                    
                    for file_obj in files:
                        row = {field: getattr(file_obj, field) for field in fieldnames}
                        writer.writerow(row)
        
        else:
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail=f"Export not supported for table: {table_name}"
            )
        
        return FileResponse(
            filename,
            media_type='text/csv',
            filename=f"{table_name}_export.csv"
        )
        
    except Exception as e:
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail=f"Export failed: {str(e)}"
        )


@router.get("/backup/download")
async def download_backup(
    current_user: User = Depends(get_admin_user)
):
    """Download database backup"""
    
    if "sqlite" in settings.database_url:
        db_path = settings.database_url.replace("sqlite:///", "")
        if os.path.exists(db_path):
            return FileResponse(
                db_path,
                media_type='application/octet-stream',
                filename=f"delphi_backup_{datetime.now().strftime('%Y%m%d_%H%M%S')}.db"
            )
    
    raise HTTPException(
        status_code=status.HTTP_404_NOT_FOUND,
        detail="Database backup not available"
    )


# User Management Endpoints

@router.get("/users", response_model=List[UserResponse])
async def list_users(
    skip: int = Query(0, ge=0),
    limit: int = Query(100, ge=1, le=1000),
    search: Optional[str] = Query(None),
    active_only: bool = Query(False),
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """List all users with pagination and filtering"""
    
    query = db.query(User)
    
    if search:
        query = query.filter(
            or_(
                User.username.ilike(f"%{search}%"),
                User.email.ilike(f"%{search}%"),
                User.first_name.ilike(f"%{search}%"),
                User.last_name.ilike(f"%{search}%")
            )
        )
    
    if active_only:
        query = query.filter(User.is_active == True)
    
    users = query.offset(skip).limit(limit).all()
    return users


@router.get("/users/{user_id}", response_model=UserResponse)
async def get_user(
    user_id: int,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Get user by ID"""
    
    user = db.query(User).filter(User.id == user_id).first()
    if not user:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="User not found"
        )
    
    return user


@router.post("/users", response_model=UserResponse)
async def create_user(
    user_data: UserCreate,
    request: Request,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Create new user"""
    
    # Check if username already exists
    existing_user = db.query(User).filter(User.username == user_data.username).first()
    if existing_user:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Username already exists"
        )
    
    # Check if email already exists
    existing_email = db.query(User).filter(User.email == user_data.email).first()
    if existing_email:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Email already exists"
        )
    
    # Create new user
    hashed_password = get_password_hash(user_data.password)
    new_user = User(
        username=user_data.username,
        email=user_data.email,
        first_name=user_data.first_name,
        last_name=user_data.last_name,
        hashed_password=hashed_password,
        is_admin=user_data.is_admin,
        is_active=user_data.is_active,
        created_at=datetime.now(),
        updated_at=datetime.now()
    )
    
    db.add(new_user)
    db.commit()
    db.refresh(new_user)
    
    # Log the user creation
    audit_service.log_user_action(
        db=db,
        action="CREATE",
        target_user=new_user,
        acting_user=current_user,
        changes={
            "username": new_user.username,
            "email": new_user.email,
            "is_admin": new_user.is_admin,
            "is_active": new_user.is_active
        },
        request=request
    )
    
    return new_user


@router.put("/users/{user_id}", response_model=UserResponse)
async def update_user(
    user_id: int,
    user_data: UserUpdate,
    request: Request,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Update user information"""
    
    user = db.query(User).filter(User.id == user_id).first()
    if not user:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="User not found"
        )
    
    # Prevent self-deactivation
    if user_id == current_user.id and user_data.is_active is False:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Cannot deactivate your own account"
        )
    
    # Check for username conflicts
    if user_data.username and user_data.username != user.username:
        existing_user = db.query(User).filter(
            User.username == user_data.username,
            User.id != user_id
        ).first()
        if existing_user:
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail="Username already exists"
            )
    
    # Check for email conflicts
    if user_data.email and user_data.email != user.email:
        existing_email = db.query(User).filter(
            User.email == user_data.email,
            User.id != user_id
        ).first()
        if existing_email:
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail="Email already exists"
            )
    
    # Track changes for audit log
    original_values = {
        "username": user.username,
        "email": user.email,
        "first_name": user.first_name,
        "last_name": user.last_name,
        "is_admin": user.is_admin,
        "is_active": user.is_active
    }
    
    # Update user fields
    update_data = user_data.model_dump(exclude_unset=True)
    changes = {}
    for field, value in update_data.items():
        if getattr(user, field) != value:
            changes[field] = {"from": getattr(user, field), "to": value}
        setattr(user, field, value)
    
    user.updated_at = datetime.now()
    
    db.commit()
    db.refresh(user)
    
    # Log the user update if there were changes
    if changes:
        audit_service.log_user_action(
            db=db,
            action="UPDATE",
            target_user=user,
            acting_user=current_user,
            changes=changes,
            request=request
        )
    
    return user


@router.delete("/users/{user_id}")
async def delete_user(
    user_id: int,
    request: Request,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Delete user (soft delete by deactivating)"""
    
    if user_id == current_user.id:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Cannot delete your own account"
        )
    
    user = db.query(User).filter(User.id == user_id).first()
    if not user:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="User not found"
        )
    
    # Soft delete by deactivating
    user.is_active = False
    user.updated_at = datetime.now()
    
    db.commit()
    
    # Log the user deactivation
    audit_service.log_user_action(
        db=db,
        action="DEACTIVATE",
        target_user=user,
        acting_user=current_user,
        changes={"is_active": {"from": True, "to": False}},
        request=request
    )
    
    return {"message": "User deactivated successfully"}


@router.post("/users/{user_id}/reset-password")
async def reset_user_password(
    user_id: int,
    password_data: PasswordReset,
    request: Request,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Reset user password"""
    
    if password_data.new_password != password_data.confirm_password:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Passwords do not match"
        )
    
    user = db.query(User).filter(User.id == user_id).first()
    if not user:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="User not found"
        )
    
    # Update password
    user.hashed_password = get_password_hash(password_data.new_password)
    user.updated_at = datetime.now()
    
    db.commit()
    
    # Log the password reset
    audit_service.log_user_action(
        db=db,
        action="RESET_PASSWORD",
        target_user=user,
        acting_user=current_user,
        changes={"password": "Password reset by administrator"},
        request=request
    )
    
    return {"message": "Password reset successfully"}


# System Settings Management

@router.get("/settings")
async def get_system_settings(
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Get all system settings"""
    
    settings = db.query(SystemSetup).all()
    return {
        "settings": [
            {
                "setting_key": setting.setting_key,
                "setting_value": setting.setting_value,
                "description": setting.description,
                "setting_type": setting.setting_type
            }
            for setting in settings
        ]
    }


@router.get("/settings/{setting_key}")
async def get_setting(
    setting_key: str,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Get specific system setting"""
    
    setting = db.query(SystemSetup).filter(SystemSetup.setting_key == setting_key).first()
    if not setting:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Setting not found"
        )
    
    return {
        "setting_key": setting.setting_key,
        "setting_value": setting.setting_value,
        "description": setting.description,
        "setting_type": setting.setting_type
    }


@router.post("/settings")
async def create_setting(
    setting_data: SystemSetting,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Create new system setting"""
    
    # Check if setting already exists
    existing_setting = db.query(SystemSetup).filter(
        SystemSetup.setting_key == setting_data.setting_key
    ).first()
    
    if existing_setting:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Setting already exists"
        )
    
    new_setting = SystemSetup(
        setting_key=setting_data.setting_key,
        setting_value=setting_data.setting_value,
        description=setting_data.description,
        setting_type=setting_data.setting_type
    )
    
    db.add(new_setting)
    db.commit()
    db.refresh(new_setting)
    
    return {
        "message": "Setting created successfully",
        "setting": {
            "setting_key": new_setting.setting_key,
            "setting_value": new_setting.setting_value,
            "description": new_setting.description,
            "setting_type": new_setting.setting_type
        }
    }


@router.put("/settings/{setting_key}")
async def update_setting(
    setting_key: str,
    setting_data: SettingUpdate,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Update system setting"""
    
    setting = db.query(SystemSetup).filter(SystemSetup.setting_key == setting_key).first()
    if not setting:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Setting not found"
        )
    
    # Update setting
    setting.setting_value = setting_data.setting_value
    if setting_data.description:
        setting.description = setting_data.description
    
    db.commit()
    db.refresh(setting)
    
    return {
        "message": "Setting updated successfully",
        "setting": {
            "setting_key": setting.setting_key,
            "setting_value": setting.setting_value,
            "description": setting.description,
            "setting_type": setting.setting_type
        }
    }


@router.delete("/settings/{setting_key}")
async def delete_setting(
    setting_key: str,
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Delete system setting"""
    
    setting = db.query(SystemSetup).filter(SystemSetup.setting_key == setting_key).first()
    if not setting:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Setting not found"
        )
    
    db.delete(setting)
    db.commit()
    
    return {"message": "Setting deleted successfully"}


# Database Maintenance and Lookup Management

@router.get("/lookups/tables")
async def get_lookup_tables(
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Get information about all lookup tables"""
    
    tables = [
        {
            "table_name": "employees",
            "display_name": "Employees",
            "record_count": db.query(func.count(Employee.empl_num)).scalar(),
            "description": "Staff/attorney information"
        },
        {
            "table_name": "file_types",
            "display_name": "File Types",
            "record_count": db.query(func.count(FileType.type_code)).scalar(),
            "description": "Case/file type definitions"
        },
        {
            "table_name": "file_statuses",
            "display_name": "File Statuses",
            "record_count": db.query(func.count(FileStatus.status_code)).scalar(),
            "description": "File status codes"
        },
        {
            "table_name": "transaction_types",
            "display_name": "Transaction Types",
            "record_count": db.query(func.count(TransactionType.t_type)).scalar(),
            "description": "Ledger transaction types"
        },
        {
            "table_name": "transaction_codes",
            "display_name": "Transaction Codes",
            "record_count": db.query(func.count(TransactionCode.t_code)).scalar(),
            "description": "Billing/expense codes"
        },
        {
            "table_name": "states",
            "display_name": "States",
            "record_count": db.query(func.count(State.abbreviation)).scalar(),
            "description": "US states and territories"
        }
    ]
    
    return {"tables": tables}


@router.post("/maintenance/vacuum")
async def vacuum_database(
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Vacuum/optimize database (SQLite only)"""
    
    if "sqlite" not in settings.database_url:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Database vacuum only supported for SQLite"
        )
    
    start_time = time.time()
    
    try:
        db.execute(text("VACUUM"))
        db.commit()
        
        end_time = time.time()
        duration = end_time - start_time
        
        return {
            "operation": "vacuum",
            "status": "success",
            "message": "Database vacuum completed successfully",
            "duration_seconds": duration
        }
        
    except Exception as e:
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail=f"Database vacuum failed: {str(e)}"
        )


@router.post("/maintenance/analyze")
async def analyze_database(
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Analyze database statistics (SQLite only)"""
    
    if "sqlite" not in settings.database_url:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Database analyze only supported for SQLite"
        )
    
    start_time = time.time()
    
    try:
        db.execute(text("ANALYZE"))
        db.commit()
        
        end_time = time.time()
        duration = end_time - start_time
        
        return {
            "operation": "analyze",
            "status": "success",
            "message": "Database analysis completed successfully",
            "duration_seconds": duration
        }
        
    except Exception as e:
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail=f"Database analysis failed: {str(e)}"
        )


@router.post("/backup/create")
async def create_backup(
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Create database backup"""
    
    if "sqlite" not in settings.database_url:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Backup creation only supported for SQLite"
        )
    
    try:
        # Create backup directory if it doesn't exist
        backup_dir = Path("backups")
        backup_dir.mkdir(exist_ok=True)
        
        # Generate backup filename
        timestamp = datetime.now().strftime("%Y%m%d_%H%M%S")
        backup_filename = f"delphi_backup_{timestamp}.db"
        backup_path = backup_dir / backup_filename
        
        # Copy database file
        db_path = settings.database_url.replace("sqlite:///", "")
        if os.path.exists(db_path):
            shutil.copy2(db_path, backup_path)
            
            # Get backup info
            backup_size = os.path.getsize(backup_path)
            
            return {
                "message": "Backup created successfully",
                "backup_info": {
                    "filename": backup_filename,
                    "size": f"{backup_size / (1024*1024):.1f} MB",
                    "created_at": datetime.now().isoformat(),
                    "backup_type": "manual",
                    "status": "completed"
                }
            }
        else:
            raise HTTPException(
                status_code=status.HTTP_404_NOT_FOUND,
                detail="Database file not found"
            )
    
    except Exception as e:
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail=f"Backup creation failed: {str(e)}"
        )


@router.get("/backup/list")
async def list_backups(
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """List available backups"""
    
    backup_dir = Path("backups")
    if not backup_dir.exists():
        return {"backups": []}
    
    backups = []
    backup_files = list(backup_dir.glob("*.db"))
    
    for backup_file in sorted(backup_files, key=lambda p: p.stat().st_mtime, reverse=True):
        stat_info = backup_file.stat()
        backups.append({
            "filename": backup_file.name,
            "size": f"{stat_info.st_size / (1024*1024):.1f} MB",
            "created_at": datetime.fromtimestamp(stat_info.st_mtime).isoformat(),
            "backup_type": "manual" if "backup_" in backup_file.name else "automatic",
            "status": "completed"
        })
    
    return {"backups": backups}


# Audit Logging and Activity Monitoring

@router.get("/audit/logs")
async def get_audit_logs(
    skip: int = Query(0, ge=0),
    limit: int = Query(100, ge=1, le=1000),
    user_id: Optional[int] = Query(None),
    resource_type: Optional[str] = Query(None),
    action: Optional[str] = Query(None),
    hours_back: int = Query(168, ge=1, le=8760),  # Default 7 days, max 1 year
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Get audit log entries with filtering"""
    
    cutoff_time = datetime.now() - timedelta(hours=hours_back)
    
    query = db.query(AuditLog).filter(AuditLog.timestamp >= cutoff_time)
    
    if user_id:
        query = query.filter(AuditLog.user_id == user_id)
    
    if resource_type:
        query = query.filter(AuditLog.resource_type.ilike(f"%{resource_type}%"))
    
    if action:
        query = query.filter(AuditLog.action.ilike(f"%{action}%"))
    
    total_count = query.count()
    logs = query.order_by(AuditLog.timestamp.desc()).offset(skip).limit(limit).all()
    
    return {
        "total": total_count,
        "logs": [
            {
                "id": log.id,
                "user_id": log.user_id,
                "username": log.username,
                "action": log.action,
                "resource_type": log.resource_type,
                "resource_id": log.resource_id,
                "details": log.details,
                "ip_address": log.ip_address,
                "user_agent": log.user_agent,
                "timestamp": log.timestamp.isoformat()
            }
            for log in logs
        ]
    }


@router.get("/audit/login-attempts")
async def get_login_attempts(
    skip: int = Query(0, ge=0),
    limit: int = Query(100, ge=1, le=1000),
    username: Optional[str] = Query(None),
    failed_only: bool = Query(False),
    hours_back: int = Query(168, ge=1, le=8760),  # Default 7 days
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Get login attempts with filtering"""
    
    cutoff_time = datetime.now() - timedelta(hours=hours_back)
    
    query = db.query(LoginAttempt).filter(LoginAttempt.timestamp >= cutoff_time)
    
    if username:
        query = query.filter(LoginAttempt.username.ilike(f"%{username}%"))
    
    if failed_only:
        query = query.filter(LoginAttempt.success == 0)
    
    total_count = query.count()
    attempts = query.order_by(LoginAttempt.timestamp.desc()).offset(skip).limit(limit).all()
    
    return {
        "total": total_count,
        "attempts": [
            {
                "id": attempt.id,
                "username": attempt.username,
                "ip_address": attempt.ip_address,
                "user_agent": attempt.user_agent,
                "success": bool(attempt.success),
                "failure_reason": attempt.failure_reason,
                "timestamp": attempt.timestamp.isoformat()
            }
            for attempt in attempts
        ]
    }


@router.get("/audit/user-activity/{user_id}")
async def get_user_activity(
    user_id: int,
    limit: int = Query(100, ge=1, le=500),
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Get activity for a specific user"""
    
    # Verify user exists
    user = db.query(User).filter(User.id == user_id).first()
    if not user:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="User not found"
        )
    
    logs = audit_service.get_user_activity(db, user_id, limit)
    
    return {
        "user": {
            "id": user.id,
            "username": user.username,
            "email": user.email,
            "first_name": user.first_name,
            "last_name": user.last_name
        },
        "activity": [
            {
                "id": log.id,
                "action": log.action,
                "resource_type": log.resource_type,
                "resource_id": log.resource_id,
                "details": log.details,
                "ip_address": log.ip_address,
                "timestamp": log.timestamp.isoformat()
            }
            for log in logs
        ]
    }


@router.get("/audit/security-alerts")
async def get_security_alerts(
    hours_back: int = Query(24, ge=1, le=168),  # Default 24 hours, max 7 days
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Get security alerts and suspicious activity"""
    
    cutoff_time = datetime.now() - timedelta(hours=hours_back)
    
    # Get failed login attempts
    failed_logins = db.query(LoginAttempt).filter(
        LoginAttempt.success == 0,
        LoginAttempt.timestamp >= cutoff_time
    ).order_by(LoginAttempt.timestamp.desc()).all()
    
    # Group failed logins by IP and username for analysis
    failed_by_ip = {}
    failed_by_username = {}
    
    for attempt in failed_logins:
        # Group by IP
        if attempt.ip_address not in failed_by_ip:
            failed_by_ip[attempt.ip_address] = []
        failed_by_ip[attempt.ip_address].append(attempt)
        
        # Group by username
        if attempt.username not in failed_by_username:
            failed_by_username[attempt.username] = []
        failed_by_username[attempt.username].append(attempt)
    
    alerts = []
    
    # Check for suspicious IPs (multiple failed attempts)
    for ip, attempts in failed_by_ip.items():
        if len(attempts) >= 5:  # Threshold for suspicious activity
            alerts.append({
                "type": "SUSPICIOUS_IP",
                "severity": "HIGH" if len(attempts) >= 10 else "MEDIUM",
                "description": f"IP {ip} had {len(attempts)} failed login attempts",
                "details": {
                    "ip_address": ip,
                    "failed_attempts": len(attempts),
                    "usernames_targeted": list(set(a.username for a in attempts)),
                    "time_range": f"{attempts[-1].timestamp.isoformat()} to {attempts[0].timestamp.isoformat()}"
                }
            })
    
    # Check for targeted usernames (multiple failed attempts on same account)
    for username, attempts in failed_by_username.items():
        if len(attempts) >= 3:  # Threshold for account targeting
            alerts.append({
                "type": "ACCOUNT_TARGETED",
                "severity": "HIGH" if len(attempts) >= 5 else "MEDIUM",
                "description": f"Username '{username}' had {len(attempts)} failed login attempts",
                "details": {
                    "username": username,
                    "failed_attempts": len(attempts),
                    "source_ips": list(set(a.ip_address for a in attempts)),
                    "time_range": f"{attempts[-1].timestamp.isoformat()} to {attempts[0].timestamp.isoformat()}"
                }
            })
    
    # Get recent admin actions
    admin_actions = db.query(AuditLog).filter(
        AuditLog.timestamp >= cutoff_time,
        AuditLog.action.in_(["DELETE", "DEACTIVATE", "RESET_PASSWORD", "GRANT_ADMIN"])
    ).order_by(AuditLog.timestamp.desc()).limit(10).all()
    
    # Add alerts for sensitive admin actions
    for action in admin_actions:
        if action.action in ["DELETE", "DEACTIVATE"]:
            alerts.append({
                "type": "ADMIN_ACTION",
                "severity": "MEDIUM",
                "description": f"Admin {action.username} performed {action.action} on {action.resource_type}",
                "details": {
                    "admin_user": action.username,
                    "action": action.action,
                    "resource_type": action.resource_type,
                    "resource_id": action.resource_id,
                    "timestamp": action.timestamp.isoformat()
                }
            })
    
    return {
        "alert_summary": {
            "total_alerts": len(alerts),
            "high_severity": len([a for a in alerts if a["severity"] == "HIGH"]),
            "medium_severity": len([a for a in alerts if a["severity"] == "MEDIUM"]),
            "failed_logins_total": len(failed_logins)
        },
        "alerts": alerts[:20],  # Return top 20 alerts
        "recent_failed_logins": [
            {
                "username": attempt.username,
                "ip_address": attempt.ip_address,
                "failure_reason": attempt.failure_reason,
                "timestamp": attempt.timestamp.isoformat()
            }
            for attempt in failed_logins[:10]
        ]
    }


@router.get("/audit/statistics")
async def get_audit_statistics(
    days_back: int = Query(30, ge=1, le=365),  # Default 30 days
    db: Session = Depends(get_db),
    current_user: User = Depends(get_admin_user)
):
    """Get audit statistics and metrics"""
    
    cutoff_time = datetime.now() - timedelta(days=days_back)
    
    # Total activity counts
    total_audit_entries = db.query(func.count(AuditLog.id)).filter(
        AuditLog.timestamp >= cutoff_time
    ).scalar()
    
    total_login_attempts = db.query(func.count(LoginAttempt.id)).filter(
        LoginAttempt.timestamp >= cutoff_time
    ).scalar()
    
    successful_logins = db.query(func.count(LoginAttempt.id)).filter(
        LoginAttempt.timestamp >= cutoff_time,
        LoginAttempt.success == 1
    ).scalar()
    
    failed_logins = db.query(func.count(LoginAttempt.id)).filter(
        LoginAttempt.timestamp >= cutoff_time,
        LoginAttempt.success == 0
    ).scalar()
    
    # Activity by action type
    activity_by_action = db.query(
        AuditLog.action,
        func.count(AuditLog.id).label('count')
    ).filter(
        AuditLog.timestamp >= cutoff_time
    ).group_by(AuditLog.action).all()
    
    # Activity by resource type
    activity_by_resource = db.query(
        AuditLog.resource_type,
        func.count(AuditLog.id).label('count')
    ).filter(
        AuditLog.timestamp >= cutoff_time
    ).group_by(AuditLog.resource_type).all()
    
    # Most active users
    most_active_users = db.query(
        AuditLog.username,
        func.count(AuditLog.id).label('count')
    ).filter(
        AuditLog.timestamp >= cutoff_time,
        AuditLog.username != "system"
    ).group_by(AuditLog.username).order_by(func.count(AuditLog.id).desc()).limit(10).all()
    
    return {
        "period": f"Last {days_back} days",
        "summary": {
            "total_audit_entries": total_audit_entries,
            "total_login_attempts": total_login_attempts,
            "successful_logins": successful_logins,
            "failed_logins": failed_logins,
            "success_rate": round((successful_logins / total_login_attempts * 100) if total_login_attempts > 0 else 0, 1)
        },
        "activity_by_action": [
            {"action": action, "count": count}
            for action, count in activity_by_action
        ],
        "activity_by_resource": [
            {"resource_type": resource_type, "count": count}
            for resource_type, count in activity_by_resource
        ],
        "most_active_users": [
            {"username": username, "activity_count": count}
            for username, count in most_active_users
        ]
    }