Add to Calender for WordPress Shortcode

functions.php

<?php

/* Event Add to Calendar Shortcode */

// Shortcode function to display Events
function display_events() {
	ob_start();
	// Get the current post ID
	$current_post_id = get_the_ID();

	// Arguments for WP_Query
	$args = array(
		'post_type' => 'events',
		'p' => $current_post_id, // Query only the current post
	);

	// Custom query
	$query = new WP_Query($args);

	// Check if any posts were found
	if ($query->have_posts()) { ?>
<div class="addto-calendar">
	<?php
		// Loop through the posts
		while ($query->have_posts()) {
			$query->the_post();

			// Retrieve title, description, and custom field
			$title = get_the_title();
			$description = get_the_content();
			$event_start_date = get_field('event_start_date');
			$event_end_date = get_field('event_end_date');
			$event_start_time = get_field('event_start_time');
			$event_end_time = get_field('event_end_time');

			$startDate_timestamp = strtotime($event_start_date);
			$endDate_timestamp = strtotime($event_end_date);
			$startTime_timestamp = strtotime($event_start_time);
			$endTime_timestamp = strtotime($event_end_time);


			// Format the date as Y/m/d
			$formatted_event_start_date = date_i18n('Ymd', $startDate_timestamp);
			$formatted_event_end_date = date_i18n('Ymd', $endDate_timestamp);
			$formatted_event_start_time = date('His', $startTime_timestamp);
			$formatted_event_end_time = date('His', $endTime_timestamp);

			
            $google_calendar_link = "https://www.google.com/calendar/render?action=TEMPLATE&text=" . urlencode($title) . "&details=" . urlencode($description) . "&location=" . urlencode($title) . "&dates=" . $formatted_event_start_date . "T" . $formatted_event_start_time . "/" . $formatted_event_end_date . "T" . $formatted_event_end_time;
            
			// Outlook Calendar link
            $outlook_calendar_link = "https://outlook.live.com/calendar/0/deeplink/compose?subject=" . urlencode($title) . "&body=" . urlencode($description) . "&location=" . urlencode($title) . "&startdt=" . $formatted_event_start_date . "T" . $formatted_event_start_time . "Z&enddt=" . $formatted_event_end_date . "T" . $formatted_event_end_time . "Z&path=/calendar/action/compose";

            // Yahoo Calendar link
            $yahoo_calendar_link = "https://calendar.yahoo.com/?v=60&view=d&type=20&title=" . urlencode($title) . "&st=" . $formatted_event_start_date . "T" . $formatted_event_start_time . "Z&dur=0100&desc=" . urlencode($description) . "&in_loc=" . urlencode($title);

            // Apple Calendar (iCal) link
            $ical_content = "BEGIN:VCALENDAR\nVERSION:2.0\nBEGIN:VEVENT\nUID:" . uniqid() . "\nDTSTAMP:" . gmdate('Ymd\THis\Z') . "\nDTSTART:" . $formatted_event_start_date . "T" . $formatted_event_start_time . "Z\nDTEND:" . $formatted_event_end_date . "T" . $formatted_event_end_time . "Z\nSUMMARY:" . $title . "\nDESCRIPTION:" . $description . "\nLOCATION:" . $title . "\nEND:VEVENT\nEND:VCALENDAR";
            $ical_file = "data:text/calendar;charset=utf8," . urlencode($ical_content);

			
	?>
	<a href="<?php echo $google_calendar_link; ?>" title="Google Calendar" target="_blank"><i class="fa-brands fa-google"></i></a>
	<a href="<?php echo $yahoo_calendar_link; ?>" title="Yahoo Calendar" target="_blank"><img src="https://fairelectionscenter.org/wp-content/uploads/2024/07/yahoo.svg"></a>
	<a href="<?php echo $outlook_calendar_link; ?>" title="Outlook Calendar" target="_blank"><img src="https://fairelectionscenter.org/wp-content/uploads/2024/07/outlook.svg"></a>
	<a href="<?php echo $ical_file; ?>" title="Apple Calendar" target="_blank"><i class="fa-brands fa-apple"></i></a>
	<?php
		}
		// Restore original post data
		
	?>
</div>
<?php }
	wp_reset_postdata();
	$myvariable = ob_get_clean();
	return $myvariable;
}
add_shortcode('display_events', 'display_events');