game.nim

let doc = """
RTS.

Usage:
  rts <hostname> <port>
"""

import asyncdispatch, zengine, sdl2, opengl, random, glm, strutils, docopt, websocket, logging, message, json

let args = docopt(doc, version = "RTS 0.1.0")

const
  ScreenWidth = 960
  ScreenHeight = 540
  SquareSize = 20
  Columns = 12
  Rows = 20
  LateralSpeed = 10
  TurningSpeed = 12
  FastFallAwaitCounter = 30
  FadingTime = 33

type
  GridSquare {.pure.} = enum
    Empty, Moving, Full, Block, Fading

var
  socket: AsyncWebSocket



let targetFramePeriod = 16.0 # 16 milliseconds corresponds to 60 fps
var frameTime: float64 = 0

proc limitFrameRate(clock: Timer) =
  let now = timeElapsed(clock) * 1000
  if frameTime > now:
    delay(uint32 frameTime - now) # Delay to maintain steady frame rate
  frameTime += targetFramePeriod

proc initGame() {.async.} =
  let 
    hostname = $args["<hostname>"]
    port = $args["<port>"]
  socket = await newAsyncWebsocket(hostname, Port(parseInt(port)), "", ssl = false, protocols = @["rts"])
  info "Connected to ws://$1:$2/rts" % [hostname, port]

  await socket.sock.sendText(toJson(createHelloMessage("bot")), true)
  
  proc reader() {.async.} =
    while true:
      echo "READING DATA"
      let read = await socket.sock.readData(true)
      echo "read: " & $read

  asyncCheck reader()    


proc updateGame(clock: Timer) =
  discard

proc drawGame(clock: var Timer) = 
  clock.tick()  

  beginDrawing()

  clearBackground(ZENGRAY)

  discard
  
  endDrawing()
  swapBuffers()

proc disposeGame() =
  discard

proc main() {.async.} =
  zengine.init(ScreenWidth, ScreenHeight, "RTS")

  await initGame()

  var
    # Window control
    evt = sdl2.defaultEvent
    running = true

  var clock = Timer()
  clock.start()

  while running:
    while sdl2.pollEvent(evt):
      case evt.kind:
        # Shutdown if X button clicked
        of QuitEvent:
          running = false
        of KeyUp:
          let keyEvent = cast[KeyboardEventPtr](addr evt)
          # Shutdown if ESC pressed
          if keyEvent.keysym.sym == K_ESCAPE:
            running = false
        else:
          discard

    updateGame(clock)

    drawGame(clock)

    limitFrameRate(clock)

  disposeGame()

  zengine.core.shutdown()

asyncCheck main()
runForever()