<?php

class MC4WP_Form_Previewer {

	public function add_hooks() {
		add_action( 'parse_request', array( $this, 'listen' ) );
	}

	public function listen() {
		if ( empty( $_GET['mc4wp_preview_form'] ) ) {
			return;
		}

		if ( ! current_user_can( 'edit_posts' ) ) {
			return;
		}

		show_admin_bar( false );
		add_filter( 'pre_handle_404', '__return_true' );
		remove_all_actions( 'template_redirect' );
		add_action( 'template_redirect', array( $this, 'load_preview' ) );
	}

	public function load_preview() {
		// clear output, some plugin or hooked code might have thrown errors by now.
		if ( ob_get_level() > 0 ) {
			ob_end_clean();
		}

		$form_id = (int) $_GET['mc4wp_preview_form'];
		status_header( 200 );

		require __DIR__ . '/views/preview.php';
		exit;
	}
}