Monitor Messageboard

local oldPull = os.pullEvent
os.pullEvent = os.pullEventRaw
local function numberString(number)
  local s = ""
  repeat
    local remainder = number % 2
    s = remainder..s
    number = (number-remainder)/2
  until number==0
  return s
end
function fromBinary(str)
  if #str % 8 ~= 0 then
    error("Malformed Binary Sequence",2)
  end
  local result = ""
  for i = 1, #str, 8 do
   result = result..string.char(tonumber(str:sub(i,i+7),2))
  end
  return result
end
function toBinary(str)
  if #str > 0 then
    local result = ""
    for a = 1, #str do
      result = result..string.format("%08d",numberString(string.byte(str:sub(a,a))))
    end
    return result
  else return nil
  end
end
local MOD = 2^32
local MODM = MOD-1
local function memoize(f)
        local mt = {}
        local t = setmetatable({}, mt)
        function mt:__index(k)
                local v = f(k)
                t[k] = v
                return v
        end
        return t
end
local function make_bitop_uncached(t, m)
        local function bitop(a, b)
                local res,p = 0,1
                while a ~= 0 and b ~= 0 do
                        local am, bm = a % m, b % m
                        res = res + t[am][bm] * p
                        a = (a - am) / m
                        b = (b - bm) / m
                        p = p*m
                end
                res = res + (a + b) * p
                return res
        end
        return bitop
end
local function make_bitop(t)
        local op1 = make_bitop_uncached(t,2^1)
        local op2 = memoize(function(a) return memoize(function(b) return op1(a, b) end) end)
        return make_bitop_uncached(op2, 2 ^ (t.n or 1))
end
local bxor1 = make_bitop({[0] = {[0] = 0,[1] = 1}, [1] = {[0] = 1, [1] = 0}, n = 4})
local function bxor(a, b, c, ...)
        local z = nil
        if b then
                a = a % MOD
                b = b % MOD
                z = bxor1(a, b)
                if c then z = bxor(z, c, ...) end
                return z
        elseif a then return a % MOD
        else return 0 end
end
local function band(a, b, c, ...)
        local z
        if b then
                a = a % MOD
                b = b % MOD
                z = ((a + b) - bxor1(a,b)) / 2
                if c then z = bit32_band(z, c, ...) end
                return z
        elseif a then return a % MOD
        else return MODM end
end
local function bnot(x) return (-1 - x) % MOD end
local function rshift1(a, disp)
        if disp < 0 then return lshift(a,-disp) end
        return math.floor(a % 2 ^ 32 / 2 ^ disp)
end
local function rshift(x, disp)
        if disp > 31 or disp < -31 then return 0 end
        return rshift1(x % MOD, disp)
end
local function lshift(a, disp)
        if disp < 0 then return rshift(a,-disp) end
        return (a * 2 ^ disp) % 2 ^ 32
end
local function rrotate(x, disp)
    x = x % MOD
    disp = disp % 32
    local low = band(x, 2 ^ disp - 1)
    return rshift(x, disp) + lshift(low, 32 - disp)
end
local k = {
        0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
        0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
        0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
        0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
        0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
        0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
        0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
        0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
        0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
        0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
        0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
        0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
        0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
        0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
        0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
        0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2,
}
local function str2hexa(s)
        return (string.gsub(s, ".", function(c) return string.format("%02x", string.byte(c)) end))
end
local function num2s(l, n)
        local s = ""
        for i = 1, n do
                local rem = l % 256
                s = string.char(rem) .. s
                l = (l - rem) / 256
        end
        return s
end
local function s232num(s, i)
        local n = 0
        for i = i, i + 3 do n = n*256 + string.byte(s, i) end
        return n
end
local function preproc(msg, len)
        local extra = 64 - ((len + 9) % 64)
        len = num2s(8 * len, 8)
        msg = msg .. "\128" .. string.rep("\0", extra) .. len
        assert(#msg % 64 == 0)
        return msg
end
local function initH256(H)
        H[1] = 0x6a09e667
        H[2] = 0xbb67ae85
        H[3] = 0x3c6ef372
        H[4] = 0xa54ff53a
        H[5] = 0x510e527f
        H[6] = 0x9b05688c
        H[7] = 0x1f83d9ab
        H[8] = 0x5be0cd19
        return H
end
local function digestblock(msg, i, H)
        local w = {}
        for j = 1, 16 do w[j] = s232num(msg, i + (j - 1)*4) end
        for j = 17, 64 do
                local v = w[j - 15]
                local s0 = bxor(rrotate(v, 7), rrotate(v, 18), rshift(v, 3))
                v = w[j - 2]
                w[j] = w[j - 16] + s0 + w[j - 7] + bxor(rrotate(v, 17), rrotate(v, 19), rshift(v, 10))
        end

        local a, b, c, d, e, f, g, h = H[1], H[2], H[3], H[4], H[5], H[6], H[7], H[8]
        for i = 1, 64 do
                local s0 = bxor(rrotate(a, 2), rrotate(a, 13), rrotate(a, 22))
                local maj = bxor(band(a, b), band(a, c), band(b, c))
                local t2 = s0 + maj
                local s1 = bxor(rrotate(e, 6), rrotate(e, 11), rrotate(e, 25))
                local ch = bxor (band(e, f), band(bnot(e), g))
                local t1 = h + s1 + ch + k[i] + w[i]
                h, g, f, e, d, c, b, a = g, f, e, d + t1, c, b, a, t1 + t2
        end

        H[1] = band(H[1] + a)
        H[2] = band(H[2] + b)
        H[3] = band(H[3] + c)
        H[4] = band(H[4] + d)
        H[5] = band(H[5] + e)
        H[6] = band(H[6] + f)
        H[7] = band(H[7] + g)
        H[8] = band(H[8] + h)
end
local function sha256(msg)
        msg = preproc(msg, #msg)
        local H = initH256({})
        for i = 1, #msg, 64 do digestblock(msg, i, H) end
        return str2hexa(num2s(H[1], 4) .. num2s(H[2], 4) .. num2s(H[3], 4) .. num2s(H[4], 4) ..
                num2s(H[5], 4) .. num2s(H[6], 4) .. num2s(H[7], 4) .. num2s(H[8], 4))
end

local mainInput = "1. Login"

local uRSInput = [[1. Admin
2. Member
3. Delete
4. Exit]]

local codeInput = [[Please enter new user code.
> ]]

local codeError = [[Invalid user code.]]

local regInput = [[New user setup, please enter new username and pass.
Username:
Password: ]]

local newOwnerInput = [[No Users detected. Enter Owner login. You must complete Owner signup or program will not function.
Username:
Password: ]]

local loginInput = [[Enter Username and Password. Leave blank to leave.
Username:
Password: ]]

local oMInput = [[Owner Menu:
1. Edit message
2. Edit User Ranks
3. Change User Code
4. Exit Program
5. Logout]]

local aMInput = [[Admin Menu:
1. Edit message
2. Edit User Ranks
3. Change User Code
4. Logout]]

local nMInput = [[Member Menu:
1. Edit message
2. Logout]]

local cCInput = [[Enter New User Access Code
> ]]

local function findMon()
  for a,v in pairs(rs.getSides()) do
    if peripheral.isPresent(v) and peripheral.getType(v) == "monitor" then
      return peripheral.wrap(v)
    end
  end
  error("No monitor connected",0)
end

local mon = findMon()
mon.setTextScale(1.5)

local function clear()
    term.clear()
    term.setCursorPos(1,1)
end

local function userRankSwap(str)
  clear()
  local filePath = fs.combine("Users/",str)
  local file = fs.open(filePath,"r")
  local fileData = textutils.unserialize(file.readAll())
  file.close()
  if fileData[2] == "Owner" then
    print("Cannot edit Owner permissions.")
    sleep(2)
    return
  end
  print("Choose rank of "..str.. ". Currently rank: "..fileData[2])
  print(uRSInput)
  while true do
    local event, param1 = os.pullEvent("char")
    if param1 == "1" then
      local file = fs.open(filePath,"w")
      fileData[2] = "Administrator"
      file.writeLine(textutils.serialize(fileData))
      file.close()
      return
    elseif param1 == "2" then
      local file = fs.open(filePath,"w")
      fileData[2] = "Member"
      file.writeLine(textutils.serialize(fileData))
      file.close()
      return
    elseif param1 == "3" then
      local file = fs.open(filePath,"w")
      fileData[2] = "Removed"
      file.writeLine(textutils.serialize(fileData))
      file.close()
      return
    elseif param1 == "4" then
      return
    end
  end
end

local function currentUsers()
  local list = fs.list("Users/")
  local totalList = {}
  for a, p in ipairs(list) do
    table.insert(totalList,a,p)
  end
  local o = 0
  local x = 0
  local y = 7
  local z = 1
  local currentList = {}
  repeat
    currentList = {}
    clear()
    y=y*z
    local a = 0
    x = y - 7
    repeat
      a=a+1
      x=x+1
      if totalList[x] == nil then
        break
      else
        table.insert(currentList,totalList[x])
        print(a..". "..totalList[x])
      end
    until a == y
    print("8. Previous")
    print("9. Next")
    print("0. Exit")
    while true do
      local event, para = os.pullEvent("char")
      local chrPara = tonumber(para)
      if chrPara then
        if (chrPara > 0 and chrPara < 8) then
          if currentList[chrPara] ~= nil then
            userRankSwap(currentList[chrPara])
            return
          elseif currentList[chrPara] == nil then
            print("File doesn't exist")
            sleep(.75)
            break
          end
        elseif chrPara == 8 then
          if o == 0 then
            print("Cannot go back")
            sleep(0.5)
            break
          elseif o ~= 0 then
            o = o-1
            x=7*8
            break
          end
        elseif chrPara == 9  then
          if totalList[x] == nil then
            print("Cannot go forward")
            sleep(0.5)
            break
          elseif totalList[x] ~= nil then
            o = o + 1
            break
          end
        elseif chrPara == 0 then
          return
        end
      end
    end
  until nil
end

local function changeMessage()
  shell.run("edit message")
end

local function changeCode()
  clear()
  write(cCInput)
  local code = read()
  if code ~= "" then
    local file = fs.open("userCode","w")
    file.writeLine(code)
    file.close()
    print("Code Saved")
    sleep(1)
  end
end

local function ownerMenu()
  clear()
  print(oMInput)
  local done = false
  repeat
    local event,param1 = os.pullEvent ("char")
    if param1 == "1" then
      changeMessage()
      done = true
    elseif param1 == "2" then
      currentUsers()
        done = true
    elseif param1 == "3" then
      changeCode()
        done = true
    elseif param1 == "4" then
        os.pullEvent = oldPull
        clear()
      error()
    elseif param1 == "5" then
        done = true
    end
  until done
end

local function adminMenu()
  clear()
  print(aMInput)
  local done = false
  repeat
    local event,param1 = os.pullEvent ("char")
    if param1 == "1" then
      changeMessage()
      done = true
    elseif param1 == "2" then
      currentUsers()
        done = true
    elseif param1 == "3" then
      changeCode()
        done = true
    elseif param1 == "4" then
        done = true
    end
  until done
end

local function memberMenu()
  clear()
  print(nMInput)
  local done = false
  repeat
    local event,param1 = os.pullEvent ("char")
    if param1 == "1" then
      changeMessage()
      done = true
    elseif param1 == "2" then
      done = true
    end
  until done
end

local function login()
  local leave = ""
  clear()
  print(loginInput)
  term.setCursorPos(11,2)
  local user = string.lower(read())
  term.setCursorPos(11,3)
  local pass = read("*")
  local filePath = fs.combine("Users/",user)
  if user == leave and pass == leave then

  elseif user == leave or pass == leave then
    print("Username or Password cannot be left blank, leave both blank to leave.")
      sleep(3)
      login()
  elseif fs.exists(filePath) then
    local file = fs.open(filePath, "r")
    local fileData = textutils.unserialize(file.readAll())
    file.close()
      local hashData = sha256(toBinary(pass))
    if hashData == fileData[1] then
      if fileData[2] == "Owner" then
        ownerMenu()
      elseif fileData[2] == "Administrator" then
        adminMenu()
      elseif fileData[2] == "Member" then
        memberMenu()
      elseif fileData[2] == "Removed" then
        print("Your account was removed")
        sleep(4)
        fs.delete(filePath)
      end
    else
      print("Username and/or Password are incorrect.")
      sleep(2)
      login()
    end
  else
    print("Username and/or Password are incorrect")
    sleep(2)
    login()
  end
end

local function register()
  local leave = ""
  clear()
  print(regInput)
  term.setCursorPos(11,2)
  local newuser = string.lower(read())
  term.setCursorPos(11,3)
  local newpass = read("*")
  if newuser == leave and newpass == leave then

  elseif newuser == leave or newpass == leave then
    print("Username and/or password cannot be blank")
    sleep(2.5)
    register()
  elseif fs.exists("Users/1"..newuser) == true then
    print("Username already exists, please try again.")
    sleep(2.5)
    register()
  else
    newpass = sha256(toBinary(newpass))
    local file = fs.open(fs.combine("Users/",newuser),"w")
    file.writeLine(textutils.serialize({newpass,"Member"}))
    file.close()
    fs.delete("userCode")
    print("User registered.")
    sleep(1)
  end
end

local function newOwner()
  local leave = ""
  fs.makeDir("Users/")
  clear()
  print(newOwnerInput)
  term.setCursorPos(11,3)
  local ownerUser = string.lower(read())
  term.setCursorPos(11,4)
  local ownerPass = read("*")
  if ownerUser == leave and ownerPass == leave then
    print("Username and/or password cannot be blank")
    sleep(2.5)
    newOwner()
  elseif ownerUser == leave or ownerPass == leave then
    print("Username and/or password cannot be blank")
    sleep(2.5)
    newOwner()
  else
    ownerPass = sha256(toBinary(ownerPass))
    local file = fs.open(fs.combine("Users/",ownerUser),"w")
    file.writeLine(textutils.serialize({ownerPass,"Owner"}))
    file.close()
    print("Registered new Owner")
    sleep(4)
  end
end

local function checkCode()
  if fs.exists("userCode") then
    clear()
    local file = fs.open("userCode","r")
    local code = file.readLine()
    file.close()
    write(codeInput)
    local input = read()
    if input == code then
      register()
    else
      write(codeError)
      sleep(1)
    end
  end
end

local function main()
  if fs.exists("Users/") then
    clear()
    print(mainInput)
    local done = false
    while not done do
      local event, param1 = os.pullEvent ("char")
      if param1 == "1" then
        login()
        done = true
      elseif param1 == "." then
        checkCode()
        done = true
      end
    end
  elseif not fs.exists("Users/") then
    newOwner()
    done = true
  end
end

local function monWrite(arg1)
  local x,y = mon.getSize()
  local z = arg1 or ""
  local getx,gety = mon.getCursorPos()
  local d = false
  while #z > x do
    getx,gety = mon.getCursorPos()
    mon.write(z:sub(1,x))
    mon.setCursorPos(1,gety+1)
    z = z:sub(x+1,#z)
    d = true
  end
  mon.write(z)
  mon.setCursorPos(1,d and gety + 2 or gety + 1)
end

local function loadMessage()
  mon.clear()
  mon.setCursorPos(1,1)
  if fs.exists("message") then
    local file = fs.open("message","r")
    local fileData = {}
    local line = file.readLine()
    while line ~= nil do
      table.insert(fileData,line)
      line = file.readLine()
    end
    file.close()
    for a = 1, #fileData do
      monWrite(fileData[a])
    end
  end
end

while true do
  loadMessage()
  main()
end