class XORBeamMeUp : GateLocal {

    override fun collectable() = true

    var partner : XORBeamMeUp = null

    // A bodge, so that we con't have to curry the player
    var warpingPlayer : Player = null

    override fun invading( movement : Movement ) {

        warpingPlayer = movement.item as Player
        val seconds = 1
        val spins = 3

        val others = PlayDirector.instance.mainStage.findRolesByClass<XORBeamMeUp>( XORBeamMeUp )
        for ( other in others ) {
            if ( other != this ) {
                partner = other
            }
        }

        replaceAction(
            (
                // Tumble the player into this gate
                ScaleTo( warpingPlayer.actor, seconds, 0.1, Eases.easeOut ) and
                TurnBy( warpingPlayer.actor.direction, seconds, Angle.degrees( 360 * spins ), Eases.easeIn ) and
                Fade( warpingPlayer.actor.color, seconds, 0, Eases.easeInQuad )

            ) thenOnce
                this:>warp then
            (
                ScaleTo( warpingPlayer.actor, seconds, 1.0, Eases.easeIn ) and
                TurnBy( warpingPlayer.actor.direction, seconds, Angle.degrees( 360 * spins ), Eases.easeOut ) and
                Fade( warpingPlayer.actor.color, seconds, 1.0, Eases.easeOutQuad )
            ) thenOnce this:>postWarp
        )
    }

    fun warp() {
        warpingPlayer.warpTo( partner.square )
    }
    fun postWarp() {
        partner.exitGate( warpingPlayer )
        warpingPlayer.replaceAction( warpingPlayer.createAction() )
    }

    // Looks ENWS for the first empty square, and moves out in that direction.
    fun exitGate( player : Player ) {
        for ( dir in 0..3 ) {
            val next = look(dir)
            if (next.isEmpty()) {
                player.autoInstructions = Item.directionAbbreviation(dir) + player.autoInstructions
                return
            }
        }
    }

    override fun invaded( movement : Movement ) : boolean {
        movement.item.replaceAction( null )
        return false
    }

}