import Graphics.Gloss.Interface.Pure.Simulate
import GHC.Float
import Data.WrapAround

dispmode = InWindow "WrapAround module test" (800, 600) (0, 0)

main = simulate dispmode (dim green) 10 model dispmodel stepfunc

data Model = Model { particles :: [(WP, (Double, Double))]
                   , wmap :: WM }
  deriving (Show)

model = let wmap' = wm 800 600 in
        let wrap (a, b) = (wp wmap' a, b) in
        Model { particles = map wrap [ ((60, 30), (10, 0))
                                     , ((110, 140), (0, 18))
                                     , ((90, 50), (-8, 14))
                                     ]
              , wmap = wmap'
              }

appPair f (x, y) = (f x, f y)

downgrade a = appPair double2Float a

dispmodel m = let s = [ let (x, y) = downgrade (coords (wmap m) p) in
                          Polygon [ (x, y)
                                  , (x + 10, y)
                                  , (x + 10, y + 10)
                                  , (x, y + 10)
                                  ]
                      | (p, _) <- particles m
                      ] in
              Translate
                (-400) (-300)
                (Pictures [ (Color black
                             (Polygon [ (800, 600)
                                      , (0, 600)
                                      , (0, 0)
                                      , (800, 0)
                                      ]))
                          , (Color green
                              (Pictures s))
                          ])

stepfunc _ _ m = m { particles = [ (add' (wmap m) p v, v)
                                 | (p, v) <- particles m
                                 ]
                   }