Counter on Card

MIN_VALUE = 0
MAX_VALUE = 50
value = 0
backValue = 0

f_size = 600

function updateSave()
   local data_to_save = {value, backValue}
   saved_data = JSON.encode(data_to_save)
   self.script_state = saved_data
end

function onload(saved_data)
   if saved_data ~= "" then
      local loaded_data = JSON.decode(saved_data)
      --Set up information off of loaded_data
      if loaded_data[1] ~= nil then value = loaded_data[1] else value = MIN_VALUE end
      if loaded_data[2] ~= nil then backValue = loaded_data[2] else backValue = MIN_VALUE end
   else
      --Set up information for if there is no saved saved data
      value = MIN_VALUE
      backValue = MIN_VALUE
   end

   createBtns()
end


--Beginning Setup


--Make setup button
function createBtns()

   local pos = { - 0.9, 0.5, - 1.1}
   local backPos = {0.9, - 0.5, - 1.1}
   local rot = {0, 0, 0}
   local backRot = {0, 0, 180}
   local h = 500
   local w = 500
   local f_color = {1, 1, 1, 255}
   local bg_color = {0, 0, 0, 0}
   local diff = 0.8

   --center display
   self.createButton({
      label = tostring(value),
      click_function = "add_subtract",
      function_owner = self,
      position = pos,
      rotation = rot,
      height = h,
      width = w,
      scale = {x = 0.25, y = 0.25, z = 0.25},
      font_size = get_size(value),
      color = f_size,
      font_color = f_color,
      color = bg_color
   })
   --Back Side
   self.createButton({
      label = tostring(backValue),
      click_function = "add_subtract_back",
      function_owner = self,
      position = backPos,
      rotation = backRot,
      height = h,
      width = w,
      scale = {x = 0.25, y = 0.25, z = 0.25},
      font_size = get_size(value),
      color = f_size,
      font_color = f_color,
      color = bg_color
   })

end

function get_size(value)
   local char_count = string.len(tostring(value))
   return f_size * 2 / (char_count + 1)
end

function add_subtract(_obj, _color, alt_click)
   mod = alt_click and - 1 or 1
   new_value = math.min(math.max(value + mod, MIN_VALUE), MAX_VALUE)
   if value ~= new_value then
      value = new_value
      updateDisplay()
      updateSave()
   end
end

function add_subtract_back(_obj, _color, alt_click)
   mod = alt_click and - 1 or 1
   new_value = math.min(math.max(backValue + mod, MIN_VALUE), MAX_VALUE)
   if backValue ~= new_value then
      backValue = new_value
      updateDisplay()
      updateSave()
   end
end

function updateDisplay()
   self.editButton({
      index = 0,
      label = tostring(value),
      font_size = get_size(value)
   })
   self.editButton({
      index = 1,
      label = tostring(backValue),
      font_size = get_size(backValue)
   })
end