-- Placed in the public domain 2020, 2022 Sam Trenholme



-- This is a version of RadioGatun[32] (RG32) which uses bit32.

-- Wikipedia has bit32 in an external library

if not bit32 then

  bit32 = require("bit32")

end



local p = {}



-- Note that belt and mill are 1-indexed here

local function beltMill(belt, mill)



  -- Mill to belt feedforward

  for z = 0, 11 do

    local offset = z + ((z % 3) * 13) + 1

    beltoffset = bit32.bxor(beltoffset],millz + 2])

  end



  -- Mill core

  local rotate = 0

  local millPrime = {}

  for z = 0, 18 do

    rotate = rotate + z

    local view = (z * 7) % 19

    local num = millview + 1

    view = (view + 1) % 19

    local viewPrime = (view + 1) % 19

    num = bit32.bxor(num,bit32.bor(millview + 1],

                     bit32.bnot(millviewPrime + 1])))

    num = bit32.rrotate(num,rotate)

    millPrimez + 1 = num

  end

  for z = 0, 18 do

    local view = (z + 1) % 19

    local viewPrime = (z + 4) % 19

    millz + 1 = bit32.bxor(millPrimez + 1],

        millPrimeview + 1],millPrimeviewPrime + 1])

  end



  -- Belt rotate

  for z = 39, 1, -1 do

     beltz + 1 = beltz

  end

  for z = 0, 2 do

     belt[(z * 13) + 1 = belt[((z + 1) * 13) + 1

  end



  -- Belt to mill

  for z = 0, 2 do

     mill14 + z = bit32.bxor(belt[(z * 13) + 1],mill14 + z])

  end



  -- Iota

  mill1 = bit32.bxor(mill1],1)

end



-- Debug function to show the belt and mill

local function showBeltMill(belt, mill)

  for z = 1, 13 do

    print(string.format("%2d %08x %08x %08x %08x",z,millz],beltz],

                        beltz + 13],beltz + 26]))

  end

  for z = 14, 19 do

    print(string.format("%2d %08x",z,millz]))

  end

end



local function initBeltMill()

  local belt = {}

  local mill = {}

  for z = 1, 40 do

    beltz = 0

  end

  for z = 1, 19 do

    millz = 0

  end

  return belt, mill

end



-- Output strings which are hex numbers in the same endian order

-- as RadioGatun[32] test vectors, given a float

local function makeLittleEndianHex(i)

  local out = ""

  for z = 1, 4 do

    i = math.floor(i)

    out = out .. string.format("%02X",i % 256)

    i = i / 256

  end

  return out

end



-- Output a 256-bit digest string, given a radiogatun state.  Affects belt and

-- mill, returns string

local function makeRG32sum(belt, mill)

  local out = ""

  for z = 1, 4 do

    out = out .. makeLittleEndianHex(mill2]) .. makeLittleEndianHex(mill3])

    beltMill(belt, mill)

  end

  return out

end



-- RadioGatun input map; given string return belt, mill

local function RG32inputMap(i)

  local belt, mill

  belt, mill = initBeltMill()

  local phase = 0;

  for a = 1, string.len(i) do

    local c = string.byte(i, a)

    local b

    c = c % 256

    c = c * (2 ^ (8 * (phase % 4)))

    b = math.floor(phase / 4) % 3

    belt[(13 * b) + 1 = bit32.bxor(belt[(13 * b) + 1],c)

    mill17 + b = bit32.bxor(mill17 + b],c)

    phase = phase + 1

    if phase % 12 == 0 then

      beltMill(belt, mill)

    end

  end



  -- Padding byte

  local b = math.floor(phase / 4) % 3

  local c = 2 ^ (8 * (phase % 4))

  belt[(13 * b) + 1 = bit32.bxor(belt[(13 * b) + 1],c)

  mill17 + b = bit32.bxor(mill17 + b],c)



  -- Blank rounds

  for z = 1, 18 do

    beltMill(belt,mill)

  end

  return belt, mill

end



-- Get the input string from a function input

-- depending on how the parent function is called, this can be a Mediawiki 

-- table with all args or it can be a simple string.

local function grabString(i)

  local input = i

  if type(input) == "table" then

    local args = nil

    local pargs = nil

    args = input.args

    pargs = input:getParent().args

    if args and args1 then 

      input = args1

    elseif pargs and pargs1 then

      input = pargs1

    else

      input = "1234" -- Default value

    end

  end

  return input

end



-- Given an input string, make a string with the hex RadioGatun[32] sum

function p.rg32sum(i)

  local belt, mill = RG32inputMap(grabString(i))

  return makeRG32sum(belt,mill)

end



-- Given an input to hash, return a formatted version of the hash

-- with both the input and hash value

function p.rg32(i)

  local input = grabString(i)

  local rginput

  -- Remove formatting from the string we give to the rg32 engine

  rginput = input:gsub("{{Background color|#%w+|(%w+)}}","%1")

  rginput = rginput:gsub("<[^>]+>","") -- Remove HTML tags

  rginput = rginput:gsub("%[%[Category[^%]]+%]%]","") -- Remove categories

  local sum = p.rg32sum(rginput)

  -- This is the output in Mediawiki markup format we give to

  -- the caller of this function

  return(' RadioGatun[32]("' .. input .. '") =\n ' .. sum)

end



-- This script is a standalone Lua script outside of the Wikipedia

if not mw then

  if arg and arg1 then

    print(p.rg32(arg1]))

  else

    print(p.rg32(

'The quick brown fox jumps over the lazy {{Background color|#87CEEB|d}}og'))

  end

end



return p