bp_messages_get_avatars( integer $thread_id, integer $user_id )

function bp_messages_get_avatars( $thread_id, $user_id ) {
	global $wpdb;

	if ( empty( $user_id ) ) {
		$user_id = bp_loggedin_user_id();
	}

	$avatar_urls      = array();
	$avatars_user_ids = array();
	$thread_messages  = BP_Messages_Thread::get_messages( $thread_id, null, 99999999 );
	$recepients       = BP_Messages_Thread::get_recipients_for_thread( $thread_id );

	if ( count( $recepients ) > 2 ) {
		foreach ( $thread_messages as $message ) {
			if ( $message->sender_id !== $user_id ) {

				if ( count( $avatars_user_ids ) >= 2 ) {
					continue;
				}

				if ( ! in_array( $message->sender_id, $avatars_user_ids ) ) {
					$avatars_user_ids[] = $message->sender_id;
				}
			}
		}
	} else {
		unset( $recepients[ $user_id ] );
		$avatars_user_ids[] = current( $recepients )->user_id;
	}

	if ( count( $recepients ) > 2 && count( $avatars_user_ids ) < 2 ) {
		unset( $recepients[ $user_id ] );
		if ( count( $avatars_user_ids ) === 0 ) {
			$avatars_user_ids = array_slice( array_keys( $recepients ), 0, 2 );
		} else {
			unset( $recepients[ $avatars_user_ids[0] ] );
			$avatars_user_ids = array_merge( $avatars_user_ids, array_slice( array_keys( $recepients ), 0, 1 ) );
		}
	}

	if ( ! empty( $avatars_user_ids ) ) {
		$avatars_user_ids = array_reverse( $avatars_user_ids );
		foreach ( (array) $avatars_user_ids as $avatar_user_id ) {
			$avatar_urls[] = array(
				'url'  => esc_url(
					bp_core_fetch_avatar(
						array(
							'item_id' => $avatar_user_id,
							'object'  => 'user',
							'type'    => 'thumb',
							'width'   => BP_AVATAR_THUMB_WIDTH,
							'height'  => BP_AVATAR_THUMB_HEIGHT,
							'html'    => false,
						)
					)
				),
				'name' => esc_attr( bp_core_get_user_displayname( $avatar_user_id ) )
			);
		}
	}


	$first_message    = end( $thread_messages );
	$first_message_id = ( ! empty( $first_message ) ? $first_message->id : false );
	$group_id         = ( isset( $first_message_id ) ) ? (int) bp_messages_get_meta( $first_message_id, 'group_id', true ) : 0;
	if ( ! empty( $first_message_id ) && ! empty( $group_id ) ) {
		$message_from  = bp_messages_get_meta( $first_message_id, 'message_from', true ); // group
		$message_users = bp_messages_get_meta( $first_message_id, 'group_message_users', true ); // all - individual
		$message_type  = bp_messages_get_meta( $first_message_id, 'group_message_type', true ); // open - private

		if ( 'group' === $message_from && 'all' === $message_users && 'open' === $message_type ) {
			if ( bp_is_active( 'groups' ) ) {
				$group_name   = bp_get_group_name( groups_get_group( $group_id ) );
				$group_avatar = array(
					'url'  => bp_core_fetch_avatar(
						array(
							'item_id'    => $group_id,
							'object'     => 'group',
							'type'       => 'full',
							'avatar_dir' => 'group-avatars',
							'alt'        => sprintf( __( 'Group logo of %s', 'buddyboss' ), $group_name ),
							'title'      => $group_name,
							'html'       => false,
						)
					),
					'name' => $group_name
				);
			} else {
				
				/**
				* 
				* Filters table prefix.
				* 
				* @param int $wpdb->base_prefix table prefix
				* 
				* @since BuddyBoss 1.4.7
				*/
				$prefix                   = apply_filters( 'bp_core_get_table_prefix', $wpdb->base_prefix );
				$groups_table             = $prefix . 'bp_groups';
				$group_name               = $wpdb->get_var( "SELECT `name` FROM `{$groups_table}` WHERE `id` = '{$group_id}';" ); // db call ok; no-cache ok;
				$group_avatar             = buddypress()->plugin_url . 'bp-core/images/mystery-group.png';
				$legacy_group_avatar_name = '-groupavatar-full';
				$legacy_user_avatar_name  = '-avatar2';

				if ( ! empty( $group_name ) ) {
					$directory         = 'group-avatars';
					$avatar_size       = '-bpfull';
					$avatar_folder_dir = bp_core_avatar_upload_path() . '/' . $directory . '/' . $group_id;
					$avatar_folder_url = bp_core_avatar_url() . '/' . $directory . '/' . $group_id;

					$avatar = bp_core_get_group_avatar( $legacy_user_avatar_name, $legacy_group_avatar_name, $avatar_size, $avatar_folder_dir, $avatar_folder_url );
					if ( '' !== $avatar ) {
						$group_avatar = array(
							'url'  => $avatar,
							'name' => $group_name
						);
					}
				}
			}

			if ( ! empty( $group_avatar ) ) {
				$avatar_urls = array( $group_avatar );
			}
		}
	}
	
	/**
	 * 
	 * Filters the avatar url array to be applied in message thread.
	 * 
	 * @param array $avatar_urls avatar urls in 
	 * @param int $thread_id Message thread id
	 * @param int $user_id user id
	 * 
	 * @since BuddyBoss 1.4.7
	 */
	return apply_filters( 'bp_messages_get_avatars', $avatar_urls, $thread_id, $user_id );
}