{-# LANGUAGE OverloadedStrings #-}
-- https://code.world/haskell#P2VuKi7iRNnijdQBr7XmDLg
import CodeWorld
import qualified Data.Text as T

type Model = Double

initial_radius :: Model
initial_radius = 5.0

drawh :: Model -> Picture
drawh r = circle r

eventh :: Event -> Model -> Model

eventh (PointerPress (x,y)) m = sqrt(x*x+y*y)

eventh (KeyPress "R") m = 1.0
eventh (KeyPress "T") m = 9.0
eventh (KeyPress _) m = initial_radius

eventh (TimePassing dt) m = m + dt
eventh _ m = m

main = activityOf initial_radius eventh drawh