module RPGEngine.Render.Level
( renderLevel
) where

import Graphics.Gloss
import RPGEngine.Data
import RPGEngine.Render.Core (getRender, setRenderPos, zoom, resolution)

renderLevel :: Level -> Picture
renderLevel Level{ layout = l, items = i, entities = e } = level
    where level    = pictures [void, layout, items, entities]
          void     = createVoid
          layout   = renderLayout l
          items    = renderItems i
          entities = renderEntities e

renderLayout :: Layout -> Picture
renderLayout strips = pictures [setRenderPos 0 y (renderStrip (strips !! y)) | y <- [0 .. count]]
    where count = length strips - 1

renderStrip :: [Physical] -> Picture
renderStrip list = pictures physicals
    where physicals       = [setRenderPos x 0 (image (list !! x)) | x <- [0 .. count]]
          image Void      = getRender "void"
          image Walkable  = getRender "tile"
          image Blocked   = getRender "wall"
          image Entrance  = pictures [getRender "tile", getRender "entrance"]
          image Exit      = pictures [getRender "tile", getRender "exit"]
          count           = length list - 1

renderItems :: [Item] -> Picture
renderItems list = pictures $ map renderItem list

renderItem :: Item -> Picture
renderItem Item{ itemId = id, itemX = x, itemY = y} = setRenderPos x y image
    where image = getRender id

renderEntities :: [Entity] -> Picture
renderEntities list = pictures $ map renderEntity list

renderEntity :: Entity -> Picture
renderEntity Entity{ entityId = id, entityX = x, entityY = y} = setRenderPos x y image
    where image = getRender id

createVoid :: Picture
createVoid = setRenderPos offX offY $ pictures voids
    where voids = [setRenderPos x y void | x <- [0 .. width], y <- [0 .. height]]
          void  = getRender "void"
          intZoom = round zoom :: Int
          height = round $ 4320 / resolution / zoom
          width  = round $ 7680 / resolution / zoom
          offX   = negate (width `div` 2)
          offY   = negate (height `div` 2)