MT | TEC | Add more display options to the ical feeds

tribe_additional_feed_views.php

<?php

/**
 * Adds more display options to the ical feeds
 * 
 * This will show recently published events, up to 40 of them:
 * events-slug/?ical=1&tribe_display=recently-published&tribe_posts_amount=40
 * 
 * This will show all events in the year 2012
 * events-slug/?ical=1&tribe_display=year&eventDate=2012
 *
 * @see pre_get_posts
 */
function tribe_additional_feed_views( $query ) {
	if ( ! isset( $_GET['ical'] ) || ! isset( $query->tribe_is_event_query ) || ! $query->tribe_is_event_query ) {
		return;
	}

	$tribe_display_unsanitized = $_GET['tribe_display'];

	if ( $tribe_display_unsanitized === 'year' ) {

		$which_year = isset( $query->query['eventDate'] ) ? strtotime( $query->query['eventDate'] ) : time();
		$start_of_year = date( 'Y', $which_year ) . '-01-01';
		$end_of_year = date( 'Y', $which_year ) . '-12-31';

		$query->set( 'eventDisplay', 'custom' );
		$query->set( 'start_date', $start_of_year );
		$query->set( 'end_date', $end_of_year );
		$query->set( 'posts_per_page', -1 );

	} elseif ( 'recently-published' === $tribe_display_unsanitized ) {

		$num_posts = isset( $_GET['tribe_posts_amount'] ) ? intval( $_GET['tribe_posts_amount'] ) : 0;

		// Uses default if $_GET is not a valid posts_per_page int
		if ( $num_posts < -1 ) {
			$num_posts = tribe_get_option( 'postsPerPage', 20 );
		}

		$query->set( 'order', 'DESC' );
		$query->set( 'orderby', 'modified' );
		$query->set( 'posts_per_page', $num_posts );

		// Remove default orderby and wheres, lest they return events sorted by event_date
		remove_filter( 'posts_orderby', array( 'Tribe__Events__Query', 'posts_orderby' ), 10 );
		remove_filter( 'posts_where', array( 'Tribe__Events__Query', 'posts_where' ), 10 );
	}
}

add_action( 'pre_get_posts', 'tribe_additional_feed_views', 100 );