<?php
/**
 * Facilitates embedding one or more maps utilizing the Google Maps API.
 */
class TribeEvents_EmbeddedMaps {
	/**
	 * Script handle for the embedded maps script.
	 */
	const MAP_HANDLE = 'tribe_events_embedded_map';

	/**
	 * @var TribeEvents_EmbeddedMaps
	 */
	protected static $instance;

	/**
	 * Post ID of the current event.
	 *
	 * @var int
	 */
	protected $event_id = 0;

	/**
	 * Post ID of the current venue (if known/if can be determined).
	 *
	 * @var int
	 */
	protected $venue_id = 0;

	/**
	 * Address of the current event/venue.
	 *
	 * @var string
	 */
	protected $address = '';

	/**
	 * Container for map address data (potentially allowing for multiple maps
	 * per page).
	 *
	 * @var array
	 */
	protected $embedded_maps = array();

	/**
	 * Indicates if the Google Maps API script has been enqueued.
	 *
	 * @var bool
	 */
	protected $map_script_enqueued = false;


	/**
	 * @return TribeEvents_EmbeddedMaps
	 */
	public static function instance() {
		if ( ! isset( self::$instance ) ) {
			self::$instance = new self;
		}

		return self::$instance;
	}

	/**
	 * Returns the placeholder HTML needed to embed a map within a page and
	 * additionally enqueues supporting scripts, etc.
	 *
	 * @param int  $post_id ID of the pertinent event or venue
	 * @param int  $width
	 * @param int  $height
	 * @param bool $force_load add the map even if no address data can be found
	 *
	 * @return string
	 */
	public function get_map( $post_id, $width, $height, $force_load ) {
		$this->get_ids( $post_id );

		// Bail if either the venue or event couldn't be determined
		if ( ! tribe_is_venue( $this->venue_id ) && ! tribe_is_event( $this->event_id ) ) {
			return apply_filters( 'tribe_get_embedded_map', '' );
		}

		$this->form_address();

		if ( empty( $this->address ) && ! $force_load ) {
			return apply_filters( 'tribe_get_embedded_map', '' );
		}

		$this->embedded_maps[] = array(
			'address' => $this->address,
			'title'   => tribe_get_venue( $this->venue_id )
		);

		end( $this->embedded_maps );
		$index = key( $this->embedded_maps );

		// Generate the HTML used to "house" the map
		ob_start();

		tribe_get_template_part( 'modules/map', null, array(
			'index'  => $index,
			'width'  => null === $width  ? apply_filters( 'tribe_events_single_map_default_width', '100%' ) : $width,
			'height' => null === $height ? apply_filters( 'tribe_events_single_map_default_height', '350px' ) : $height,
		) );

		$this->setup_scripts();
		do_action( 'tribe_events_map_embedded', $index, $this->venue_id );
		return apply_filters( 'tribe_get_embedded_map', ob_get_clean() );
	}

	protected function get_ids( $post_id ) {
		$post_id = $post_id = TribeEvents::postIdHelper( $post_id );
		$this->event_id = tribe_is_event( $post_id ) ? $post_id : 0;
		$this->venue_id  = tribe_is_venue( $post_id ) ? $post_id : tribe_get_venue_id( $post_id );
	}

	protected function form_address() {
		$this->address = '';
		$location_parts = array( 'address', 'city', 'state', 'province', 'zip', 'country' );

		// Form the address string for the map
		foreach ( $location_parts as $val ) {
			$address_part = call_user_func( 'tribe_get_' . $val, $this->venue_id );
			if ( $address_part ) {
				$this->address .= $address_part . ' ';
			}
		}
	}

	public function get_map_data( $map_index ) {
		return isset( $this->embedded_maps[$map_index] ) ? $this->embedded_maps[$map_index] : array();
	}

	public function update_map_data( $map_index, array $data ) {
		$this->embedded_maps[$map_index] = $data;
		$this->setup_scripts();
	}

	protected function setup_scripts() {
		if ( ! $this->map_script_enqueued ) {
			$this->enqueue_map_scripts();
		}

		// Provide address data
		wp_localize_script( self::MAP_HANDLE, 'tribeEventsSingleMap', array(
			'addresses' => $this->embedded_maps,
			'zoom' => apply_filters( 'tribe_events_single_map_zoom_level', (int) tribe_get_option( 'embedGoogleMapsZoom', 8 ) )
		));
	}

	protected function enqueue_map_scripts() {
		// Setup Google Maps API
		$url = apply_filters( 'tribe_events_google_maps_api', '//maps.googleapis.com/maps/api/js' );
		wp_enqueue_script( 'tribe_events_google_maps_api', $url, array(), false, true );

		// Setup our own script used to initialize each map
		$resources_url = trailingslashit( TribeEvents::instance()->pluginUrl ) . 'resources/';
		$url = Tribe_Template_Factory::getMinFile( $resources_url . 'embedded-map.js', true );
		wp_enqueue_script( self::MAP_HANDLE, $url, array( 'tribe_events_google_maps_api' ), false, true );

		$this->map_script_enqueued = true;
	}
}