from flask import request
from functools import wraps
from marshmallow import ValidationError
from app.common.responses import error_response


def validate_request(schema_class):
    """
    Decorator to validate incoming JSON request data against a marshmallow schema.

    Usage:
        @customer.route("/create", methods=["POST"])
        @validate_request(CreateCustomerSchema)
        def create_customer():
            data = request.validated_data  # Access validated data
            ...
    """
    def decorator(f):
        @wraps(f)
        def decorated_function(*args, **kwargs):
            # Check if request has JSON data
            if not request.is_json:
                return error_response("Request must be JSON", 400)

            json_data = request.get_json()
            if json_data is None:
                return error_response("Invalid JSON data", 400)

            # Validate the data
            schema = schema_class()
            try:
                validated_data = schema.load(json_data)
                # Attach validated data to request object for easy access
                request.validated_data = validated_data
            except ValidationError as err:
                return error_response("Validation failed", 400, details=str(err.messages))

            return f(*args, **kwargs)
        return decorated_function
    return decorator


def validate_json(schema_class, data):
    """
    Validate data against a schema and return (validated_data, errors).

    Usage:
        data, errors = validate_json(CreateCustomerSchema, request.get_json())
        if errors:
            return jsonify({"error": "Validation failed", "details": errors}), 400
    """
    schema = schema_class()
    try:
        validated_data = schema.load(data or {})
        return validated_data, None
    except ValidationError as err:
        return None, err.messages