from flask import jsonify, request
from models.department import Department
from models.user import User
import csv
import io
import bcrypt
import random
import string
import logging

# Configure logging
logger = logging.getLogger(__name__)

def generate_random_password(length=12):
    """Generate a random password"""
    characters = string.ascii_letters + string.digits
    return ''.join(random.choice(characters) for _ in range(length))

def create_department():
    """Create a new department with its first admin user"""
    data = request.get_json()
    
    # Check if required fields are present
    required_fields = ['name', 'address', 'website', 'admin_email', 'admin_name', 'admin_password']
    for field in required_fields:
        if field not in data:
            return jsonify({'message': f'Missing required field: {field}'}), 400
    
    # Check if department with this name already exists
    existing_department = Department.find_by_name(data['name'])
    if existing_department:
        return jsonify({'message': 'Department with this name already exists'}), 400
    
    # Check if user with this email already exists
    existing_user = User.find_by_email(data['admin_email'])
    if existing_user:
        return jsonify({'message': 'User with this email already exists'}), 400
    
    try:
        # Log the request data for debugging
        logger.info(f"Creating new department with data: {data}")
        
        # Create department
        department = Department(
            name=data['name'],
            address=data['address'],
            website=data['website']
        )
        
        # Save department and log the result
        save_result = department.save()
        logger.info(f"Department saved with _id: {department._id}, save result: {save_result}")
        
        # Create admin user
        hashed_password = User.hash_password(data['admin_password'])
        admin_user = User(
            email=data['admin_email'],
            name=data['admin_name'],
            password=hashed_password,
            permissions='Admin',
            position=data.get('admin_position', 'Administrator'),
            department_id=department._id
        )
        
        # Save user and log the result
        user_save_result = admin_user.save()
        logger.info(f"Admin user saved with _id: {admin_user._id}, save result: {user_save_result}")
        
        # Add admin to department members and log the result
        member_add_result = department.add_member(admin_user._id)
        logger.info(f"Adding admin user to department members, result: {member_add_result}")
        
        # Check if the member was added correctly
        updated_department = Department.find_by_id(department._id)
        logger.info(f"Updated department members: {updated_department.members if updated_department else 'Department not found'}")
        
        # Return success response with detailed information
        return jsonify({
            'message': 'Department and admin user created successfully',
            'department': {
                **department.to_dict(),
                'members_debug': [str(member) for member in department.members]
            },
            'admin_user': admin_user.to_dict(),
            'success': True
        }), 201
        
    except Exception as e:
        import traceback
        logger.error(f"Error creating department: {str(e)}")
        logger.error(f"Traceback: {traceback.format_exc()}")
        return jsonify({'message': f'Error creating department: {str(e)}'}), 500

def get_department(department_id):
    """Get department by ID"""
    department = Department.find_by_id(department_id)
    if not department:
        return jsonify({'message': 'Department not found'}), 404
    
    return jsonify({'department': department.to_dict()}), 200

def update_department(department_id):
    """Update department details"""
    department = Department.find_by_id(department_id)
    if not department:
        return jsonify({'message': 'Department not found'}), 404
    
    data = request.get_json()
    
    # Update fields if provided
    if 'name' in data:
        department.name = data['name']
    if 'address' in data:
        department.address = data['address']
    if 'website' in data:
        department.website = data['website']
    
    # Save changes
    if department.save():
        return jsonify({'message': 'Department updated successfully', 'department': department.to_dict()}), 200
    else:
        return jsonify({'message': 'Failed to update department'}), 500

def delete_department(department_id):
    """Delete a department"""
    department = Department.find_by_id(department_id)
    if not department:
        return jsonify({'message': 'Department not found'}), 404
    
    # Delete all users in the department
    users = User.find_by_department(department_id)
    for user in users:
        user.delete()
    
    # Delete the department
    if department.delete():
        return jsonify({'message': 'Department and all its users deleted successfully'}), 200
    else:
        return jsonify({'message': 'Failed to delete department'}), 500

def get_all_departments():
    """Get all departments"""
    departments = Department.get_all()
    return jsonify({'departments': [department.to_dict() for department in departments]}), 200

def add_members_csv(department_id):
    """Add multiple members to a department using CSV upload"""
    department = Department.find_by_id(department_id)
    if not department:
        return jsonify({'message': 'Department not found'}), 404
    
    if 'file' not in request.files:
        return jsonify({'message': 'No file part'}), 400
    
    file = request.files['file']
    if file.filename == '':
        return jsonify({'message': 'No selected file'}), 400
    
    if file and file.filename.endswith('.csv'):
        try:
            # Read CSV data
            csv_data = file.read().decode('utf-8')
            csv_reader = csv.DictReader(io.StringIO(csv_data))
            
            # Process each row
            new_users = []
            errors = []
            
            required_fields = ['email', 'name', 'position', 'permissions']
            
            for row_index, row in enumerate(csv_reader, start=1):
                # Check if all required fields are present
                missing_fields = [field for field in required_fields if field not in row or not row[field]]
                
                if missing_fields:
                    errors.append(f"Row {row_index}: Missing required fields: {', '.join(missing_fields)}")
                    continue
                
                # Check if user already exists
                if User.find_by_email(row['email']):
                    errors.append(f"Row {row_index}: User with email {row['email']} already exists")
                    continue
                
                # Check if permissions are valid
                if row['permissions'] not in ['Admin', 'User']:
                    row['permissions'] = 'User'  # Default to User if invalid
                
                # Generate random password
                password = generate_random_password()
                hashed_password = User.hash_password(password)
                
                # Create new user
                user = User(
                    email=row['email'],
                    name=row['name'],
                    password=hashed_password,
                    permissions=row['permissions'],
                    position=row['position'],
                    department_id=department._id
                )
                
                if user.save():
                    # Add user to department
                    department.add_member(user._id)
                    
                    # Store for response (including the raw password)
                    user_dict = user.to_dict()
                    user_dict['raw_password'] = password
                    new_users.append(user_dict)
                else:
                    errors.append(f"Row {row_index}: Failed to save user {row['email']}")
            
            # Return results
            return jsonify({
                'message': f"Processed {len(new_users)} new users with {len(errors)} errors",
                'new_users': new_users,
                'errors': errors
            }), 200
            
        except Exception as e:
            logger.error(f"Error processing CSV: {str(e)}")
            return jsonify({'message': f'Error processing CSV: {str(e)}'}), 500
    else:
        return jsonify({'message': 'File must be a CSV'}), 400

def add_member(department_id, current_user=None):
    """Add a single member to a department"""
    department = Department.find_by_id(department_id)
    if not department:
        return jsonify({'message': 'Department not found'}), 404
    
    data = request.get_json()
    
    # Check if required fields are present
    required_fields = ['email', 'name', 'position', 'permissions']
    for field in required_fields:
        if field not in data:
            return jsonify({'message': f'Missing required field: {field}'}), 400
    
    # Check if user already exists
    if User.find_by_email(data['email']):
        return jsonify({'message': 'User with this email already exists'}), 400
    
    # Check if permissions are valid
    if data['permissions'] not in ['Admin', 'User']:
        data['permissions'] = 'User'  # Default to User if invalid
    
    try:
        # Generate random password if not provided
        password = data.get('password', generate_random_password())
        hashed_password = User.hash_password(password)
        
        # Create new user
        user = User(
            email=data['email'],
            name=data['name'],
            password=hashed_password,
            permissions=data['permissions'],
            position=data['position'],
            department_id=department._id
        )
        
        if user.save():
            # Add user to department
            department.add_member(user._id)
            
            # Return the raw password in the response
            user_dict = user.to_dict()
            user_dict['raw_password'] = password
            
            return jsonify({
                'message': 'User added successfully',
                'user': user_dict
            }), 201
        else:
            return jsonify({'message': 'Failed to save user'}), 500
            
    except Exception as e:
        logger.error(f"Error adding member: {str(e)}")
        return jsonify({'message': f'Error adding member: {str(e)}'}), 500

def get_department_members(department_id, current_user=None):
    """Get all members of a department"""
    # Log input parameters
    logger.info(f"get_department_members called with department_id: {department_id}")
    if current_user:
        logger.info(f"Current user: {current_user._id}, {current_user.email}, Department: {current_user.department_id}")
    
    # Find department by ID
    department = Department.find_by_id(department_id)
    if not department:
        logger.error(f"Department with ID {department_id} not found")
        return jsonify({'message': 'Department not found'}), 404
    
    # Log department info
    logger.info(f"Found department: {department.name}, ID: {department._id}")
    logger.info(f"Department members list (raw): {department.members}")
    logger.info(f"Department has {len(department.members)} members in its members array")
    
    # Find users by department
    logger.info(f"Calling User.find_by_department with department_id: {department_id}")
    users = User.find_by_department(department_id)
    
    # Log result
    logger.info(f"User.find_by_department returned {len(users)} users")
    for user in users:
        logger.info(f"Found user: {user._id}, {user.email}, Department: {user.department_id}")
    
    # Return response
    return jsonify({'members': [user.to_dict() for user in users]}), 200

def remove_member(department_id, user_id, current_user=None):
    """Remove a member from a department"""
    department = Department.find_by_id(department_id)
    if not department:
        return jsonify({'message': 'Department not found'}), 404
    
    user = User.find_by_id(user_id)
    if not user:
        return jsonify({'message': 'User not found'}), 404
    
    # Check if user belongs to the department
    if str(user.department_id) != str(department._id):
        return jsonify({'message': 'User does not belong to this department'}), 400
    
    # Remove user from department
    if department.remove_member(user_id) and user.delete():
        return jsonify({'message': 'User removed successfully'}), 200
    else:
        return jsonify({'message': 'Failed to remove user'}), 500

def update_member_permissions(department_id, user_id, current_user=None):
    """Update a member's permissions"""
    department = Department.find_by_id(department_id)
    if not department:
        return jsonify({'message': 'Department not found'}), 404
    
    user = User.find_by_id(user_id)
    if not user:
        return jsonify({'message': 'User not found'}), 404
    
    # Check if user belongs to the department
    if str(user.department_id) != str(department._id):
        return jsonify({'message': 'User does not belong to this department'}), 400
    
    data = request.get_json()
    
    # Check if permissions are provided
    if 'permissions' not in data:
        return jsonify({'message': 'Permissions not provided'}), 400
    
    # Check if permissions are valid
    if data['permissions'] not in ['Admin', 'User']:
        return jsonify({'message': 'Invalid permissions. Must be "Admin" or "User"'}), 400
    
    # Update permissions
    user.permissions = data['permissions']
    
    if user.save():
        return jsonify({'message': 'User permissions updated successfully', 'user': user.to_dict()}), 200
    else:
        return jsonify({'message': 'Failed to update user permissions'}), 500

def debug_department(department_id, current_user=None):
    """Debug endpoint to get detailed information about a department and its members"""
    logger.info(f"debug_department called with department_id: {department_id}")
    if current_user:
        logger.info(f"Called by user: {current_user._id}, {current_user.email}, Permissions: {current_user.permissions}")
    
    # Find department directly from MongoDB
    from db import get_departments_collection, get_users_collection
    from bson import ObjectId
    
    dept_id_obj = ObjectId(department_id) if isinstance(department_id, str) else department_id
    logger.info(f"Looking up department with ObjectId: {dept_id_obj}")
    
    # Get raw department data
    departments_collection = get_departments_collection()
    department_data = departments_collection.find_one({"_id": dept_id_obj})
    
    if not department_data:
        logger.error(f"Department with ID {department_id} not found in database")
        return jsonify({'message': 'Department not found'}), 404
    
    # Get department object
    department = Department.find_by_id(department_id)
    
    # Get users collection
    users_collection = get_users_collection()
    
    # Find all users in database
    all_users = list(users_collection.find())
    logger.info(f"Total users in database: {len(all_users)}")
    
    # Collect user info for all department members
    member_info = []
    for member_id in department_data.get('members', []):
        # Try to find user by ID
        user_data = users_collection.find_one({"_id": member_id})
        if user_data:
            member_info.append({
                "user_id": str(member_id),
                "found_in_db": True,
                "email": user_data.get('email'),
                "name": user_data.get('name'),
                "department_id": str(user_data.get('department_id')) if user_data.get('department_id') else None
            })
        else:
            member_info.append({
                "user_id": str(member_id),
                "found_in_db": False
            })
    
    # Find all users with this department_id
    users_with_dept = list(users_collection.find({"department_id": dept_id_obj}))
    logger.info(f"Found {len(users_with_dept)} users with department_id matching {dept_id_obj}")
    
    users_info = []
    for user_data in users_with_dept:
        users_info.append({
            "user_id": str(user_data.get('_id')),
            "email": user_data.get('email'),
            "name": user_data.get('name'),
            "in_members_array": any(str(user_data.get('_id')) == str(m) for m in department_data.get('members', []))
        })
    
    # Build response with detailed info
    response = {
        "department": {
            "_id": str(department_data.get('_id')),
            "name": department_data.get('name'),
            "raw_members": [str(m) for m in department_data.get('members', [])],
            "member_count": len(department_data.get('members', [])),
            "members_detail": member_info
        },
        "users_with_department_id": {
            "count": len(users_with_dept),
            "users": users_info
        }
    }
    
    return jsonify(response), 200