practice/love/mike/lib/keys.lua

require "lib/GameState"

QUIT_KEY = "q"
SAVE_KEY = "s"
LOAD_KEY = "l"
HALF_SPEED = "lshift"
MOVE_RIGHT = "right"
MOVE_LEFT = "left"
SAVE_FILE = "testing.lua"

function love.keyreleased(key)
  if key == QUIT_KEY then
      love.event.quit()

  -- save
  elseif key == SAVE_KEY then
    --love.filesystem.write(saveFile, Tserial.pack(player, false, true))
		love.filesystem.write(SAVE_FILE, GameState.save(actors, "actors"))

  -- Load
  elseif key == LOAD_KEY then
  	
		save_exists = love.filesystem.exists(SAVE_FILE)

    if save_exists then
      --player = Tserial.unpack( love.filesystem.read( saveFile ) )
			GameState.load(SAVE_FILE)
    end 
  end 
end

function half_speed(object_speed)
	if love.keyboard.isDown(HALF_SPEED) then
		return object_speed/2
	else return object_speed
	end
end

function check_keys(object, screen, dt) 
  local newObject = {}
  newObject.x = object.x
  newObject.y = object.y
  newObject.width = object.width
  newObject.height = object.height
  newObject.speed = object.speed
	
	if love.keyboard.isDown(MOVE_RIGHT)  then
    newObject.x = newObject.x + half_speed(newObject.speed * dt)
  end

	if love.keyboard.isDown(MOVE_LEFT) then
		newObject.x = newObject.x - half_speed(newObject.speed * dt)
	end

	if screen_col_detect(newObject, screen) then
		return newObject
	else
		return object
	end
end

--Inspired by https://love2d.org/wiki/BoundingBox.lua
--Returns true if boxes overlap