SaaS codebase your AI can actually understand

'use client';

import { useMutation } from '@tanstack/react-query';
import type { CreateCheckoutSessionInput } from '../schemas';

interface UseCreateCheckoutOptions {
    onSuccess?: (url: string) => void;
    onError?: (error: Error) => void;
}

export function useCreateCheckout(options: UseCreateCheckoutOptions = {}) {
    const { onSuccess, onError } = options;

    return useMutation({
        mutationFn: async (data: CreateCheckoutSessionInput) => {
            const response = await fetch('/api/payment/create-checkout', {
                method: 'POST',
                headers: { 'Content-Type': 'application/json' },
                body: JSON.stringify(data),
            });

            const result = await response.json();

            if (!response.ok || !result.success) {
                throw new Error(result.error || 'Failed to create checkout session');
            }

            if (!result.data?.url) {
                throw new Error('No checkout URL returned');
            }

            return result.data;
        },
        onSuccess: (data) => {
            if (data.url) {
                window.location.href = data.url;
            }
            onSuccess?.(data.url);
        },
        onError: (error: Error) => {
            onError?.(error);
        },
    });
}