For SportsPress - Add a player list on the fly to the current team.

sportspress-add-player-list-automatically.php

<?php

/**
 * Add a player list on the fly to the current team.
 */
add_action(
	'init',
	function () {

		/**
		 * Configuration.
		 *
		 * @var array  {
		 *     @type boolean filter_by_league       Filter by league.
		 *     @type boolean filter_by_season       Filter by season.
		 *     @type boolean filter_by_current_team Filter by current team.
		 *     @type int     priority               Filter priority. Use 9 or lower to place the additional content above
		 *                                          any other SportsPress elements.
		 * }
		 */
		$config = array(
			'filter_by_league'       => true,
			'filter_by_season'       => true,
			'filter_by_current_team' => true,
			'priority'               => 0,
		);

		/* That's all, stop editing! Happy sportspress'ing. */

		add_filter(
			'the_content',
			function ( $content ) use ( $config ) {

				$object = get_queried_object();

				/**
				 * Exit if this is not a SportsPress team.
				 */

				if ( 'sp_team' !== $object->post_type ) {
					return $content;
				}

				/**
				 * Build the output.
				 *
				 * We use the shortcode `[player_list team=? seasons=? leagues=?]`.
				 * If `filter_by_current_team` is false, we will filter players and only
				 * show the ones whose team is the current one.
				 */

				$id     = $object->ID;
				$league = $config['filter_by_league'] ? get_option( 'sportspress_league' ) : false;
				$season = $config['filter_by_season'] ? get_option( 'sportspress_season' ) : false;

				$force_current_teams_cb = $config['filter_by_current_team']
					? function ( $args, $team ) {
						$args['meta_query'][] = array(
							array(
								'key'   => 'sp_current_team',
								'value' => $team,
							),
						);
						return $args;
					}
					: function ( $args ) {
						return $args;
					};

				add_filter( 'sportspress_player_list_args', $force_current_teams_cb, 10, 2 );
				$additional_content = do_shortcode(
					sprintf(
						'[player_list team=%d %s %s]',
						$id,
						$season ? "seasons=$season" : '',
						$league ? "leagues=$league" : ''
					)
				);
				remove_filter( 'sportspress_player_list_args', $force_current_teams_cb, 10, 2 );

				/**
				 * Done
				 */
				return $content . $additional_content;
			},
			$config['priority']
		);
	}
);