signature APP_INIT =
sig
  val fromWindowWidthAndHeight: int * int * int * int -> AppType.app_type
end

structure AppInit :> APP_INIT =
struct
  open AppType

  fun helpFromWidthAndHeight
    ( windowWidth
    , windowHeight
    , wStart
    , wFinish
    , hStart
    , hFinish
    , canvasWidth
    , canvasHeight
    ) : app_type =
    let
      val xClickPoints = ClickPoints.generate (wStart, wFinish, canvasWidth)
      val yClickPoints = ClickPoints.generate (hStart, hFinish, canvasHeight)

      val maxPoints = Int.max (canvasWidth, canvasHeight)
      val squares = Vector.tabulate (maxPoints, fn _ =>
        Vector.tabulate (maxPoints, fn _ => 0))
    in
      { mode = AppType.NORMAL_MODE
      , squares = squares
      , canvasWidth = canvasWidth
      , canvasHeight = canvasHeight
      , windowWidth = windowWidth
      , windowHeight = windowHeight
      , xClickPoints = xClickPoints
      , yClickPoints = yClickPoints

      , mouseX = 0.0
      , mouseY = 0.0
      , showGraph = true
      , arrowX = 0
      , arrowY = 0
      , openFilePath = ""
      , fileBrowser = Vector.fromList []
      , fileBrowserIdx = 0
      , r = 0.0
      , g = 0.0
      , b = 0.0
      , modalNum = 0
      }
    end

  fun fromWindowWidthAndHeight
    (windowWidth, windowHeight, canvasWidth, canvasHeight) =
    if windowWidth > windowHeight then
      let
        val difference = windowWidth - windowHeight
        val wStart = difference div 2
        val wFinish = wStart + windowHeight
      in
        helpFromWidthAndHeight
          ( windowWidth
          , windowHeight
          , wStart
          , wFinish
          , 0
          , windowHeight
          , canvasWidth
          , canvasHeight
          )
      end
    else
      let
        val difference = windowHeight - windowWidth
        val hStart = difference div 2
        val hFinish = hStart + windowWidth
      in
        helpFromWidthAndHeight
          ( windowWidth
          , windowHeight
          , 0
          , windowWidth
          , hStart
          , hFinish
          , canvasWidth
          , canvasHeight
          )
      end
end