from rest_framework.exceptions import APIException
from rest_framework import status
from rest_framework.views import exception_handler as drf_exception_handler
from rest_framework.response import Response
from rest_framework.exceptions import ValidationError



def error_response(error_code, message, details=None, status_code=status.HTTP_400_BAD_REQUEST):
    # print(f'>>>> {error_code}')
    response_data = {
        "status": "error",
        "code": error_code,
        "message": message,
        "details": details or {}
    }
    
    return Response(response_data, status=status_code)


def exception_handler(exc, context):
    # Call REST framework's default exception handler first,
        # to get the standard error response.
    response = drf_exception_handler(exc, context)
    # قالب‌بندی جدید خطاها
    formatted_errors = []

    if response is not None:
        # تعیین نوع خطاها   
        print(f'>>> {type(exc)}/ {exc}')

        if isinstance(exc, ValidationError):
            error_code = "validation_error"
            message = "There were validation errors."

            if isinstance(response.data, list):
                for error in response.data:
                    formatted_errors.append({
                        "field": None,  # No specific field when the error is a list
                        "message": error
                    })
           
            else: 
                # فرمت کردن خطاها به فرمت جدید
                print(f'>>>>>> {response.data}')
                for field, errors in response.data.items():
                    if isinstance(errors, list):
                        for error in errors:
                            # print()
                            # print(f'>>>> {field}')
                            formatted_errors.append({
                                "field": field,
                                "message": error
                            })
                    else:
                        formatted_errors.append({
                            "field": field,
                            "message": errors
                        })
    
                seen_fields = set()
                for i in range(len(formatted_errors) - 1, -1, -1):
                    field = formatted_errors[i]['field']
                    if field in seen_fields:
                        # اگر فیلد تکراری بود، آن را حذف کن
                        del formatted_errors[i]
                    else:
                        # اولین باری که فیلد دیده شده، آن را ثبت کن
                        seen_fields.add(field)
                        
        elif isinstance(exc, AppAPIException):
            error_code = "app_api_error"
            message = "An error occurred while processing the request."
            for field, errors in response.data.items():
                if isinstance(errors, list):
                    for error in errors:
                        formatted_errors.append({
                            "message": error
                        })
                else:
                    formatted_errors.append({
                        "message": errors
                    })
            
            
        else:
            error_code = "server_error"
            message = "An error occurred."
            # فرمت کردن خطاها به فرمت جدید
            for field, errors in response.data.items():
                if isinstance(errors, list):
                    for error in errors:
                        formatted_errors.append({
                            "message": error
                        })
                else:
                    formatted_errors.append({
                        "message": errors
                    })



            
        # تنظیم ساختار جدید برای پاسخ خطا
        response.data = {
            "status": "error",
            "code": error_code,
            "status_code": response.status_code,  # Adding the status code
            "message": message,
            "errors": formatted_errors
        }

    return response


class AppAPIException(APIException):
    status_code = status.HTTP_400_BAD_REQUEST  
    default_detail = 'An error occurred while processing the request.'
    
    def __init__(self, detail=None, status_code=None):
        if detail is None:
            detail = self.default_detail
        if status_code is None:
            status_code = self.default_code
        else:
            self.status_code = status_code
        super().__init__(detail, status_code)



class ExpiredCodeException(APIException):
    status_code = status.HTTP_410_GONE
    default_detail = "The verification code has expired."
    default_code = "expired_code"

class UserNotFoundException(APIException):
    status_code = status.HTTP_404_NOT_FOUND
    default_detail = 'user notfound'
class NotFoundException(APIException):
    status_code = status.HTTP_404_NOT_FOUND
    default_detail = "The requested resource was not found."
    default_code = "not_found"
    
    
class InvaliedCodeVrify(APIException):
    status_code = status.HTTP_400_BAD_REQUEST
    default_detail = "code notfound"
    
    
class ServiceUnavailableException(APIException):
    status_code = status.HTTP_500_INTERNAL_SERVER_ERROR
    default_detail = 'Service temporarily unavailable'
    default_code = 'service_unavailable'