PMPro integration for WPForms that adds "Require Membership" settings to the "General" settings of a Form. Also has integration with PMPro Series Add-On to prevent access to forms if not yet available in the series flow.

pmpro-wpforms-snippets.php

<?php

/**
 * Add output that explains that the person does not have access to this form.
 *
 * Customize this to fit your needs!
 */
function my_pmpro_wpform_locked_message() {
	// Set your level ID here so they know where to go to sign up. Non-existent ID will just send them to the Membership Levels page.
	$level_id = 9999999;
	?>
	<p>
		<?php esc_html_e( 'You do not have access to this form.', 'pmpro-wpforms-snippets' ); ?>
		<?php echo pmpro_getCheckoutButton( $level_id ); ?>
	</p>
	<?php
}

/**
 * Add output that explains that the person does not have access to this form yet.
 *
 * Customize this to fit your needs!
 */
function my_pmpro_wpform_locked_message_in_series() {
	?>
	<p>
		<?php esc_html_e( 'You do not have access to this form yet.', 'pmpro-wpforms-snippets' ); ?>
	</p>
	<?php
}

/**
 * Filter the list of post types supported for PMPro Series UI.
 *
 * @param array $post_types The list of post types supported for PMPro Series UI.
 *
 * @return array The list of post types supported.
 */
function my_pmpro_wpform_post_types_for_series( array $post_types ) {
	$post_types[] = 'wpforms';

	return $post_types;
}

add_filter( 'pmpros_post_types', 'my_pmpro_wpform_post_types_for_series' );

/**
 * Filter whether the form should be loaded based on if it is locked or not.
 *
 * @param bool  $load_form Indicates whether a form should be loaded.
 * @param array $form_data Form information.
 *
 * @return bool Whether the form is locked.
 */
function my_pmpro_wpform_can_form_be_accessed( $load_form, $form_data ) {
	// Check if PMPro is active.
	if ( ! function_exists( 'pmpro_hasMembershipLevel' ) ) {
		return $load_form;
	}

	// Don't do anything if we cannot load the form anyways.
	if ( ! $load_form ) {
		return $load_form;
	}

	// Get the form post ID.
	$form_id = $form_data['id'];

	// Get the current user ID to use when checking access.
	$user_id = get_current_user_id();

	$required_levels = [];

	// Loop through all of the settings to find our level-specific values.
	foreach ( $form_data['settings'] as $key => $setting_value ) {
		// It must start with "pmpro_require_membership_".
		if ( 0 !== strpos( $key, 'pmpro_require_membership_' ) ) {
			continue;
		}

		// It must be checked (1).
		if ( 1 !== (int) $setting_value ) {
			continue;
		}

		// Add the level ID to the list.
		$required_levels[] = str_replace( 'pmpro_require_membership_', '', $key );
	}

	// Check if they have access to the levels specified.
	if ( $required_levels && ! pmpro_hasMembershipLevel( $required_levels, $user_id ) ) {
		add_action( 'wpforms_frontend_not_loaded', 'my_pmpro_wpform_locked_message' );

		return false;
	}

	// Check if member has access from a series.
	if ( function_exists( 'pmpros_hasAccess' ) ) {
		add_action( 'wpforms_frontend_not_loaded', 'my_pmpro_wpform_locked_message_in_series' );

		return pmpros_hasAccess( $user_id, $form_id );
	}

	return true;
}

add_filter( 'wpforms_frontend_load', 'my_pmpro_wpform_can_form_be_accessed', 10, 2 );

/**
 * Register panel fields.
 *
 * @param object $instance Settings panel instance.
 */
function my_pmpro_wpform_register_panel_fields( $instance ) {
	// Check if PMPro is active.
	if ( ! function_exists( 'pmpro_getAllLevels' ) ) {
		return;
	}

	$levels = pmpro_getAllLevels( true, true );

	$heading = false;

	foreach ( $levels as $level ) {
		$args = [];

		if ( ! $heading ) {
			$heading = true;

			$args['before'] = '<h2>' . esc_html__( 'Require Membership', 'pmpro-wpforms-snippets' ) . '</h2>';
		}

		wpforms_panel_field(
			'checkbox',
			'settings',
			'pmpro_require_membership_' . sanitize_key( $level->id ),
			$instance->form_data,
			sprintf( esc_html__( 'Require Membership Level: %s', 'pmpro-wpforms-snippets' ), $level->name ),
			$args
		);
	}
}

add_action( 'wpforms_form_settings_general', 'my_pmpro_wpform_register_panel_fields', 30, 2 );

/**
 * Filter the post link for Conditional Forms.
 *
 * @param string  $post_link The post link.
 * @param WP_Post $post      The post object.
 *
 * @return string|void
 */
function my_pmpro_wpform_filter_post_link( $post_link, $post ) {
	if ( ! function_exists( 'wpforms_decode' ) ) {
		return $post_link;
	}

	if ( 'wpforms' !== $post->post_type ) {
		return $post_link;
	}

	$form_data = wpforms_decode( $post->post_content );

	if ( ! $form_data || empty( $form_data['settings']['conversational_forms_enable'] ) ) {
		return $post_link;
	}

	return home_url( $post->post_name );
}

add_filter( 'post_type_link', 'my_pmpro_wpform_filter_post_link', 10, 2 );