sprite_number.lua

local str_digit_to_frame= {}
for i= 0, 9 do
	str_digit_to_frame[tostring(i)]= i
end

local function sprite_number(digits, commands)
	local parts= {}
	local spacing= 32
	local midpoint= spacing * digits * .5
	local frame= Def.ActorFrame(commands)
	local internal= false
	local part_holder= Def.ActorFrame{
		InitCommand= function(self)
			internal= self
		end,
	}
	frame[#frame+1]= part_holder
	frame.SetCommand= function(self, number)
		-- 5.1-new or 5.0.x compat
		if type(number) == "table" then
			number= number[1]
		end
		-- reverse the string because part[1] is the ones digit.
		local str= ("%i"):format(math.floor(number)):reverse()
		local last= math.min(#str, #parts)
		for sid= 1, last do
			local part= parts[sid]
			local was_vis= part:GetVisible()
			local prev_state= part:GetState()
			local new_state= str_digit_to_frame[str:sub(sid, sid)]
			part:setstate(new_state)
			part:visible(true)
			if not was_vis or prev_state ~= new_state then
				part:playcommand("Bounce")
			end
		end
		for pid= last+1, #parts do
			local part= parts[pid]
			part:visible(false)
		end
		local width= last * spacing
		internal:x((width * .5) + midpoint)
	end
	for id= 1, digits do
		part_holder[#part_holder+1]= Def.Sprite{
			Texture= THEME:GetPathG("", "grades/number_grades"),
			InitCommand= function(self)
				parts[id]= self
				self:animate(false)
				-- lowest id digit is the ones place
					:x((id-1) * -spacing)
					:visible(false)
			end,
			BounceCommand= function(self)
				self:finishtweening()
					:spring(.2):y(-8)
					:spring(.2):y(0)
			end,
		}
	end
	return frame
end

local curr_value= 0
local sprnum= false

local function input(event)
	if event.type == "InputEventType_Release" then return end
	local button= event.DeviceInput.button
	if button == "DeviceButton_f" then
		curr_value= math.max(0, curr_value - 1)
		sprnum:playcommand("Set", curr_value)
	elseif button == "DeviceButton_j" then
		curr_value= math.min(999999, curr_value + 1)
		sprnum:playcommand("Set", curr_value)
	end
end

local frame= Def.ActorFrame{
	quaid(_screen.cx, _screen.cy, _screen.w, _screen.h, {.7, .7, .7, .7}),
	OnCommand= function(self)
		sprnum= self:GetChild("sprnum")
		SCREENMAN:GetTopScreen():AddInputCallback(input)
		sprnum:playcommand("Set", curr_value)
	end,
	sprite_number(6, {Name= "sprnum", InitCommand= function(self) self:Center() end}),
}

return frame