module Dodge.LevelGen.SwarmPlacement
    ( swarmPS
    )
    where
import Dodge.Data
import Dodge.LevelGen.Data
import Dodge.Creature.State.Data
--import Geometry
import Geometry.ConvexPoly
import qualified IntMapHelp as IM

import Data.List
import qualified Data.IntSet as IS
import Control.Lens

swarmPS :: Int -> Point2 -> Float -> Creature -> Placement
swarmPS i p a cr = GroupedPlacement
    { _groupPlacementID = i
    , _groupUpdate = setSwarm
--    , _groupPlacementFunc = setSwarm i
    , _placementSpot = PS p a $ PutCrit cr
    }
setSwarm :: World -> [Placement] -> World
setSwarm w ps = updateCrs w' & creatureGroups %~ IM.insert gid theGroupParams
  where
    (w', crs) = mapAccumR updateCrit w ps
    is = IS.fromList $ map _crID crs
    cpos = centroid $ map _crPos crs
    gid = IM.newKey (_creatureGroups w')
    theGroupParams = CrGroupParams
        { _crGroupParamID = gid
        , _crGroupIDs = is
        , _crGroupCenter = cpos
        , _crGroupUpdate = crGroupUpdateCenter
        }
    updateCrs w'' = IS.foldl' (\w''' cid -> w''' & creatures . ix cid %~ setSwarmStatus) w'' is
    setSwarmStatus = crGroup .~ Swarm {_swarm = is, _crGroupID = gid}

crGroupUpdateCenter :: World -> CrGroupParams -> Maybe CrGroupParams
crGroupUpdateCenter w cgp 
    | IM.null crs = Nothing
    | otherwise = Just $ cgp & crGroupCenter .~
        centroid (IM.map _crPos crs)
  where
    crs = IM.restrictKeys (_creatures w) (_crGroupIDs cgp)

updateCrit :: World -> Placement -> (World, Creature)
updateCrit w pl = (w & creatures %~ IM.insert cid cr
    , cr
    )
  where 
    p = _psPos $ _placementSpot pl
    rot = _psRot $ _placementSpot pl
    scr = _unPutCrit $ _psType $ _placementSpot pl
    cid = IM.newKey (_creatures w)
    cr = scr {_crPos = p,_crOldPos = p,_crDir = rot,_crID = cid}