-- NES Braidulator VERSION 1
--(C) Antony Lavelle 2009       got_wot@hotmail.com      http://www.the-exp.net
-- A Lua script that allows 'Braid' style time reversal for Nes games being run in FCEUX
--'Braid' is copyright Jonathan Blow, who is not affiliated with this script, but you should all buy his game because it's ace.
--This is my first ever time scripting in Lua, so if you can improve on this idea/code please by all means do and redistribute it, just please be nice and include original credits along with your own :)



--Change these settings to adjust options


--Which key you would like to function as the "rewind key"

local rewindKey = 'select'


--How much rewind power would you like? (The higher the number the further back in time you can go, but more computer memory is used up)
--Do not set to 0!

local saveMax = 1000;




--The stuff below is for more advanced users, enter at your own peril!



local saveArray = {};--the Array in which the save states are stored
local saveCount = 1;--used for finding which array position to cycle through
local save; -- the variable used for storing the save state
local rewindCount = 0;--this stops you looping back around the array if theres nothing at the end
local savePreventBuffer = 1;--Used for more control over when save states will be saved, not really used in this version much.
while (true) do
	savePreventBuffer = savePreventBuffer-1;
	if savePreventBuffer==0 then
		savePreventBuffer = 1;
	end;
	joyput	= joypad.read(1);
	if joyput[rewindKey] then
		savePreventBuffer = 5;
		if rewindCount==0 then
			--makes sure you can't go back too far could also include other things in here, left empty for now.	
		else	
			savestate.load(saveArray[saveCount]);
			saveCount = saveCount-1;
			rewindCount = rewindCount-1;
			if saveCount==0 then		
				saveCount = saveMax-1;
			end;
		end;
	end;
	if savePreventBuffer==1 then
		gui.text(80,15,"");
		saveCount=saveCount+1;
		if saveCount==saveMax then
			saveCount = 1;
		end
		rewindCount = rewindCount+1;
		if rewindCount==saveMax-1 then
			rewindCount = saveMax-2;
		end;
		save = savestate.create();
		savestate.save(save);
		saveArray[saveCount] = save;
	end;
	local HUDMATH = (math.ceil((100/saveMax)*rewindCount));--Making the rewind time a percentage.
	local HUDTEXT = "REWIND POWER: ".. HUDMATH .."%"; 
	gui.text(80,5,HUDTEXT);--Displaying the time onscreen.
	FCEU.frameadvance();
end;