-- Setup Terminology abbreviations; from FractalFusion
local bnd,br,bxr=bit.band,bit.bor,bit.bxor
local rshift, lshift=bit.rshift, bit.lshift
local mdword=memory.readdwordunsigned
local mword=memory.readwordunsigned
local mbyte=memory.readbyteunsigned
local wdword=memory.writedword
local md,mw,mb=memory.readdwordunsigned,memory.readwordunsigned,memory.readbyteunsigned

local game=0 -- 0 for white2, 1 for black2
local rng=0x021FFC58-0x20*game -- PRNG Seed Location
local mtrng=0x021FED68-0x20*game -- Mersenne Twister Table Top
local mac=0x123456 -- MAC Address of Emulator
local pos_m=md(0x02000024)+0x36780

local storage=0x02000200
local trackcgear=0 -- 0 on, 1 off; disable for Standard Abuse, enable for Entralink Abuse
local research=0 -- 0 on, 1 off; only enable for dev features (unneeded)



-- Setup initial variables, rest of script detection will take care of them
local initl=0
local inith=0
local initm=0
local adv=0
local jump1=0
local jump2=0
local jump3=0
local jump4=0
local jump5=0
local jump6=0
local jump7=0
local jump8=0
local jump9=0
local jump10=0
local jump11=0
local jump12=0
local jump13=0
local jump14=0
local jump15=0
local jump16=0
local jump17=0
local jump18=0
local jump19=0
local jump20=0
local total=0
local last=0
local lastm=0
local lmtp=0
local steptable=0
local mtf=0
local mttrack=0
local nextmt=0
local second=0
local minute=0
local hour=0
local cgearoff=0
local cachevalue=0
local notrestored=0
local wasrestored=0

-- S frame detection function; works off of seeing how many times the lower half was advanced
-- Lua sucks and only allows 16 bit multiplication, so 32 bit multiplication can't be used
-- The lower seed is advanced as follows, if observed as a standalone 32 bit number:
-- SEED1 = (0x6C078965 * SEED1) + 0x00269EC3; from Kazo
function next(s)
local a=0x6C07*(s%65536)+rshift(s,16)*0x8965
local b=0x8965*(s%65536)+(a%65536)*65536+0x00269EC3
local c=b%4294967296
return c
end

-- To predict Mersenne advancement, it's a little harder. Copied and adapted pre-existing Lua
-- http://code.google.com/p/gocha-tas/s...9937.lua?r=117
-- Mersenne Twister: A random number generator
-- ported to Lua by gocha, based on mt19937ar.c
module("mt19937", package.seeall)

require "bit"

-- Period parameters
local N = 624
local M = 397
local MATRIX_A = 0x9908b0df -- constant vector a
local UPPER_MASK = 0x80000000 -- most significant w-r bits
local LOWER_MASK = 0x7fffffff -- least significant r bits

local mt = {} -- the array for the state vector
local mti = N + 1 -- mti==N+1 means mt[N] is not initialized

-- initializes mt[N] with a seed
function randomseed(s)
s = bit.band(s, 0xffffffff)
mt[1] = s
for i = 1, N - 1 do
-- s = 1812433253 * (bit.bxor(s, bit.rshift(s, 30))) + i
s = bit.bxor(s, bit.rshift(s, 30))
local s_lo = bit.band(s, 0xffff)
local s_hi = bit.rshift(s, 16)
local s_lo2 = bit.band(1812433253 * s_lo, 0xffffffff)
local s_hi2 = bit.band(1812433253 * s_hi, 0xffff)
s = bit.bor(bit.lshift(bit.rshift(s_lo2, 16) + s_hi2, 16),
bit.band(s_lo2, 0xffff))
-- s = bit.band(s + i, 0xffffffff)
local s_lim = -bit.tobit(s)
-- assumes i<2^31
if (s_lim > 0 and s_lim <= i) then
s = i - s_lim
else
s = s + i
end
mt[i+1] = s
-- See Knuth TAOCP Vol2. 3rd Ed. P.106 for multiplier.
-- In the previous versions, MSBs of the seed affect
-- only MSBs of the array mt[].
-- 2002/01/09 modified by Makoto Matsumoto
end
mti = N
end

local mag01 = { 0, MATRIX_A } -- mag01[x] = x * MATRIX_A for x=0,1

-- generates a random number on [0,0xffffffff]-interval
function random_int32()
local y

if (mti >= N) then -- generate N words at one time
local kk

if (mti == N + 1) then -- if init_genrand() has not been called,
mt19937.randomseed(5489) -- a default initial seed is used
end

for kk = 1, N - M do
y = bit.bor(bit.band(mt[kk], UPPER_MASK), bit.band(mt[kk+1], LOWER_MASK))
mt[kk] = bit.bxor(mt[kk+M], bit.rshift(y, 1), mag01[1 + bit.band(y, 1)])
end
for kk = N - M + 1, N - 1 do
y = bit.bor(bit.band(mt[kk], UPPER_MASK), bit.band(mt[kk+1], LOWER_MASK))
mt[kk] = bit.bxor(mt[kk+(M-N)], bit.rshift(y, 1), mag01[1 + bit.band(y, 1)])
end
y = bit.bor(bit.band(mt[N], UPPER_MASK), bit.band(mt[1], LOWER_MASK))
mt[N] = bit.bxor(mt[M], bit.rshift(y, 1), mag01[1 + bit.band(y, 1)])

mti = 0
end

y = mt[mti+1]
mti = mti + 1



return y
end

function random(...)
-- local r = mt19937.random_int32() * (1.0/4294967296.0)
local rtemp = mt19937.random_int32()
local r = (bit.band(rtemp, 0x7fffffff) * (1.0/4294967296.0)) + (bit.tobit(rtemp) < 0 and 0.5 or 0)
local arg = {...}
if #arg == 0 then
return r
elseif #arg == 1 then
local u = math.floor(arg[1])
if 1 <= u then
return math.floor(r*u)+1
else
error("bad argument #1 to 'random' (internal is empty)")
end
elseif #arg == 2 then
local l, u = math.floor(arg[1]), math.floor(arg[2])
if l <= u then
return math.floor((r*(u-l+1))+l)
else
error("bad argument #2 to 'random' (internal is empty)")
end
else
error("wrong number of arguments")
end
end

-- Lua script begin!
function main()
wdword(storage,1)
-- setup every loop
seed2=mdword(rng+4)
seed1=mdword(rng)
adv=0
test=last
mtv=mdword(mtrng)
mtp=mdword(mtrng+0x9C0)
delay=mdword(0x02FFFC3C)
timehex=mdword(0x023FFDEC)
datehex=mdword(0x023FFDE8)
hour=string.format("%02X",(timehex%0x100)%0x40) -- memory stores as decimal, but Lua reads as hex. Convert.
minute=string.format("%02X",(rshift(timehex%0x10000 ,8)))
second=string.format("%02X",(mbyte(0x02FFFDEE)))
year=string.format("%02X",(mbyte(0x02FFFDE8)))
month=string.format("%02X",(mbyte(0x02FFFDE9)))
day=string.format("%02X",(mbyte(0x02FFFDEA)))

-- display seeds every loop
gui.text(1,10,string.format("Current: %08X%08X",seed2,seed1))
gui.text(1,180,string.format("Initial: %08X%08X",inith,initl))
gui.text(1,170, string.format("M: %d, X: %d, Y: %d, Z: %d", mword(pos_m), mword(pos_m+0x6), mword(pos_m+0xE), mword(pos_m+0xA)))

-- Check to see if the RNG advanced from the last value
while seed1~=0 and seed2~=0 and delay > 2 do
if adv>200 then -- RNG advanced a bunch, or the game/script was reset. Reset variables then stop loop.
steptable=0
adv =0
jump1=0
jump2=0
jump3=0
jump4=0
jump5=0
jump6=0
jump7=0
jump8=0
jump9=0
jump10=0
jump11=0
jump12=0
jump13=0
jump14=0
jump15=0
jump16=0
jump17=0
jump18=0
jump19=0
jump20=0
if mdword(storage)==1 and delay>3 and mdword(storage+0x4*2)~=0 then
print(""..string.format("Restoring session. Please Wait..."))
steptable=mdword(storage+0x4*1) -- restore mt
initm=mdword(storage+0x4*2)
lastm=mdword(storage+0x4*7)
randomseed(initm)
i=624*steptable+1
while i>0 do -- restore internal mt frame
nextmt=math.floor(random_int32())
i=i-1 
end

mttrack=1 -- turn on tracking

inith=mdword(storage+0x4*4) -- restore PRNG
initl=mdword(storage+0x4*3)

cacheseed=mdword(storage+0x4*5)
cachevalue=mdword(storage+0x4*6)
lastm=mtv
mtv=lastm
lmtp=mtp

if initm==0 or inith==0 or initl==0 then 
print(""..string.format("Save state's session did not start with script.")) 
print(""..string.format("Either load a valid save state or resume with this one."))
initl=mdword(rng) -- reset to session
inith=mdword(rng+4)
mttrack=0
emu.pause()
total=0
steptable=0
mtf=0
lmtp=mtp
steptable=0
else
print(""..string.format("PRNG: %08X%08X",inith,initl)) 
print(""..string.format("MTRNG: %08X", initm))
last=cacheseed
total=cachevalue -- restored frame
end
cgearoff=mdword(storage+0x4*8) -- remember if c-gear was turned on or not
notrestored=1
wasrestored=1
elseif initm==inith then
print(""..string.format("Game Reset. Re-initializing."))
total=0
steptable=0
mtf=0
lmtp=mtp
initl=mdword(rng)
inith=mdword(rng+4)
initm=mdword(mtrng)
if inith>0x7FFFFFFF then wdword(storage+0x4*4,inith-0x100000000) else wdword(storage+0x4*4,inith) end -- dumb storage problems, have to make sure they are recognized as the right number type before storage
if initl>0x7FFFFFFF then wdword(storage+0x4*3,initl-0x100000000) else wdword(storage+0x4*3,initl) end
if initm>0x7FFFFFFF then wdword(storage+0x4*2,initm-0x100000000) else wdword(storage+0x4*2,initm) end
lastm=initm
randomseed(initm)
mttrack=1 -- enable mersenne tracking
nextmt=random_int32() -- get first untempered mersenne value, this is the value that will replace the MTRNG seed in the memory when the table is redone
cgearenoff=0
wasrestored=0

print(""..string.format("Session Initial Seed: %08X%08X",inith,initl)) 
--print(""..string.format("Next: %08X", nextmt)) -- debug

-- see if initial seeding happened (high32=mtseed)
mttrack=1 -- enable tracking
print(""..string.format("Initial Seeding Detected. MTRNG Seed: %08X", initm))
else 
print(""..string.format("Foreign Save State Detected, or Restart didn't refresh. Reset again."))
total=0
steptable=0
mtf=0
lmtp=mtp
initl=mdword(rng)
inith=mdword(rng+4)
initm=mdword(mtrng)
if inith>0x7FFFFFFF then wdword(storage+0x4*4,inith-0x100000000) else wdword(storage+0x4*4,inith) end
if initl>0x7FFFFFFF then wdword(storage+0x4*3,initl-0x100000000) else wdword(storage+0x4*3,initl) end
if initm>0x7FFFFFFF then wdword(storage+0x4*2,initm-0x100000000) else wdword(storage+0x4*2,initm) end
lastm=initm
randomseed(initm)
mttrack=0 -- disable mersenne tracking
nextmt=random_int32() -- get first untempered mersenne value, this is the value that will replace the MTRNG seed in the memory when the table is redone
cgearenoff=0
wasrestored=0
end
print(""..string.format("")) -- Visual Line to separate.
break 

elseif test~=seed1 then -- RNG advanced at least once. Lets advance once and repeat the loop.
test=next(test)
adv=adv+1

elseif test==seed1 then 
if adv > 0 then -- Refresh Frame Advancement Table if there's more than one advancement this frame.
jump20=jump19
jump19=jump18
jump18=jump17
jump17=jump16
jump16=jump15
jump15=jump14
jump14=jump13
jump13=jump12
jump12=jump11
jump11=jump10
jump10=jump9
jump9=jump8
jump8=jump7
jump7=jump6
jump6=jump5
jump5=jump4
jump4=jump3
jump3=jump2
jump2=jump1
jump1=adv 
end 
break -- last frame's advanced RNG value matches the current. Stop loop.
end
end


gui.text(180,10,string.format("%d/%d/%d",month,day,2000+year)) -- Display Date
gui.text(180,19,string.format("%02d:%02d:%02d",hour,minute,second,delay)) -- Display Time

-- Check to see if the MTRNG changed, only if tracking is enabled.
if mttrack==1 and notrestored == 0 then
if (lmtp>mtp and delay > 50 and notrestored==0) or (lmtp==mtp and lastm~=mtv) then
strmtv=string.format("%08X",mtv) -- Mersenne Twister untempered is in one format while the memory is in another
strnmt=string.format("%08X",nextmt) -- Convert to a string hex so that they can be equated when their decimal isn't
if strmtv~=strnmt then -- New untempered table value isn't as predicted, so the c-gear was turned on!
mttrack=1 
-- print(strmtv,strnmt,string.format("%08X",lastm)) -- debug for bad initialize
if wasrestored==1 then print(""..string.format("Earlier restoration may have failed. Double Check.")) print(""..string.format("If C-Gear was just turned on this frame, ignore.")) print(""..string.format("")) wasrestored=0 end
-- mttrack=0
--else 
print(""..string.format("C-Gear turned on. Determining C-Gear Seed and restarting tracking.")) 
steptable=1
wdword(storage+0x4*1, steptable)
-- Finding the C-Gear seed you hit
-- Load Time Values
hour=string.format("%02X",(timehex%0x100)%0x40) -- Memory stores as decimal, but Lua reads as hex. Convert.
minute=string.format("%02X",(rshift(timehex%0x10000,8)))
second=string.format("%02X",(mbyte(0x02FFFDEE)))
year=string.format("%02X",(mbyte(0x02FFFDE8)))
month=string.format("%02X",(mbyte(0x02FFFDE9)))
day=string.format("%02X",(mbyte(0x02FFFDEA)))
ab=(month*day+minute+second)%256
cd=hour
cgd=delay%65536-1 -- Delay from a frame before is used.
abcd=ab*0x100+cd
efgh=(year+cgd)%0x10000
tempcgear=(ab*0x1000000+cd*0x10000+efgh+mac)%0x100000000
randomseed(tempcgear)
trialseed=random_int32()
tempcgearuntemp=string.format("%08X",trialseed)
if strmtv~=tempcgearuntemp then
second=second-1 -- Subtract a second to check a different set.
if second < 0 then -- Balaning minutes
second=59
minute=minute-1 
if minute<0 then -- Balancing Hours
minute=59
hour=hour-1
end
end
ab=(month*day+minute+second)%256 -- Rebuild seed, try again.
cd=hour
abcd=ab*0x100+cd
efgh=(year+cgd)%0x10000
tempcgear=(ab*0x1000000+cd*0x10000+efgh+mac)%0x100000000
randomseed(tempcgear)
trialseed=random_int32()
tempcgearuntemp=string.format("%08X",trialseed)
end

initm=tempcgear
print(""..string.format("C-Gear Seed: %08X Delay: %d",tempcgear,cgd))
print(""..string.format("")) -- Visual Blank Line
cgearenabled=2
wdword(storage+0x4*8,cgearenabled) 
if initm>0x7FFFFFFF then wdword(storage+0x4*2,initm-0x100000000) else wdword(storage+0x4*2,initm) end
i=0
while i~=624 do -- get the next untempered for the cgear
nextmt=math.floor(random_int32())
i=i+1
end --end
else -- untempered is as predicted -> predict next one for when the time rolls around

i=0
while i~=624 do -- do 624 iterations to build the remaining 623 and the first of the next.
nextmt=math.floor(random_int32())
i=i+1
end
--print(""..string.format("Next: %08X", nextmt)) -- debug



steptable=steptable+1 -- mersenne twister has a new table as the is reset to 0; tables++

wdword(storage+0x4*1, steptable) -- save state storage of table refreshes
end
end
gui.text(1,160,string.format("MTRNG Seed: %08X",initm))
gui.text(1,150,string.format("Frame: %d",mtf))
-- gui.text(1,38,string.format("next mt: %08X", nextmt)) -- debug
end


-- Advancement Tracking for the PRNG and Mersenne Twister
total=adv+total -- total advancements = advancements on this frame + total advancements from previous frames
if total-cachevalue>200 then -- check to see if we should refresh the cached value
cachevalue=total
end
mtf=mtp+(steptable-1)*624 -- Mersenne Twister Frame = Pointer Value + (TableRefresh-1)*624 ; this accounts for the initial value of 0x270 which is actually zero

gui.text(1,19,string.format("Frame: %d", total)) -- Display PRNG Frame; total advancements since the initial seed

-- If the user specifies they want to use the C-Gear

-- If user specifies they want to see the frame advancement chart
if research==0 then -- Display framebased advancement table
gui.text(1,37,string.format("%d", jump1)) gui.text(1,46,string.format("%d", jump2)) gui.text(1,55,string.format("%d", jump3)) gui.text(1,64,string.format("%d", jump4))
gui.text(1,73,string.format("%d", jump5)) gui.text(1,82,string.format("%d", jump6)) gui.text(1,91,string.format("%d", jump7)) gui.text(1,100,string.format("%d", jump8))
gui.text(1,109,string.format("%d", jump9)) gui.text(1,118,string.format("%d", jump10)) gui.text(20,37,string.format("%d", jump11)) gui.text(20,46,string.format("%d", jump12)) 
gui.text(20,55,string.format("%d", jump13)) gui.text(20,64,string.format("%d", jump14)) gui.text(20,73,string.format("%d", jump15)) gui.text(20,82,string.format("%d", jump16)) 
gui.text(20,91,string.format("%d", jump17)) gui.text(20,100,string.format("%d", jump18)) gui.text(20,109,string.format("%d", jump19)) gui.text(20,118,string.format("%d", jump20))
end

-- Set Up variables for next frame's pass
lmtp=mtp
last=seed1
lastm=mtv
if lastm>0x7FFFFFFF then wdword(storage+0x4*7,lastm-0x100000000) else wdword(storage+0x4*7,lastm) end
wdword(storage+0x4*6,total)
if seed1>0x7FFFFFFF then wdword(storage+0x4*5,seed1-0x100000000) else wdword(storage+0x4*5,seed1) end

notrestored=0
-- End Lua
end

gui.register(main)