view.js

let formSettings;
try {
	formSettings = JSON.parse(
		document.getElementById(
			'wp-script-module-data-@wordpress/block-library/form/view'
		)?.textContent
	);
} catch {}

// eslint-disable-next-line eslint-comments/disable-enable-pair
/* eslint-disable no-undef */
document.querySelectorAll( 'form.wp-block-form' ).forEach( function ( form ) {
	// Bail If the form settings not provided or the form is not using the mailto: action.
	if (
		! formSettings ||
		! form.action ||
		! form.action.startsWith( 'mailto:' )
	) {
		return;
	}

	const redirectNotification = ( status ) => {
		const urlParams = new URLSearchParams( window.location.search );
		urlParams.append( 'wp-form-result', status );
		window.location.search = urlParams.toString();
	};

	// Add an event listener for the form submission.
	form.addEventListener( 'submit', async function ( event ) {
		event.preventDefault();
		// Get the form data and merge it with the form action and nonce.
		const formData = Object.fromEntries( new FormData( form ).entries() );
		formData.formAction = form.action;
		formData._ajax_nonce = formSettings.nonce;
		formData.action = formSettings.action;
		formData._wp_http_referer = window.location.href;
		formData.formAction = form.action;

		try {
			const response = await fetch( formSettings.ajaxUrl, {
				method: 'POST',
				headers: {
					'Content-Type': 'application/x-www-form-urlencoded',
				},
				body: new URLSearchParams( formData ).toString(),
			} );
			if ( response.ok ) {
				redirectNotification( 'success' );
			} else {
				redirectNotification( 'error' );
			}
		} catch ( error ) {
			redirectNotification( 'error' );
		}
	} );
} );