atm

local channels = {
  atm = 1,
  db = 2,
}

os.loadAPI("/common")
os.loadAPI("/sha256")

local modem = peripheral.find("modem")
modem.open(channels.atm)

local function sendCmd(...)
  modem.transmit(channels.db, channels.atm, {...})
  local resp = common.waitForMsg(channels.db, 2)
  if resp then
    if resp[1] then
      return resp
    else
      printError(resp[2])
    end
  else
    printError("Timed out")
  end
  return resp
end

while true do
  term.clear()
  term.setCursorPos(1,1)
  print("1. Register\n2. Login\n3. Exit")
  write("> ")
  local mode = tonumber(read())

  term.clear()
  term.setCursorPos(1,1)

  if mode == 1 then
    print("Register an account")
    write("Username: ")
    local username = read()
    write("Password: ")
    local password = read("*")
    local salt = sendCmd("register", username)
    if salt and salt[1] then
      local hash = sha256.pbkdf2(password, salt[2], 64):toHex()
      sendCmd(true, hash)
      print("Account created!")
    end

    sleep(2)

  elseif mode == 2 then
    print("Log-in into your account")
    write("Username: ")
    local username = read()
    write("Password: ")
    local password = read("*")
    local salt = sendCmd("auth", username)
    if salt and salt[1] then
      local hash = sha256.pbkdf2(password, salt[2], 64):toHex()
      local resp = sendCmd(true, hash)
      if resp and resp[1] then
        while true do
          term.clear()
          term.setCursorPos(1,1)
          print("Logged in as "..username)
          print("1. Check Balance\n2. Transfer money\n3. Deposit\n4. Withdraw\n5. Exit")
          write("> ")
          local mode = tonumber(read())
          if mode == 1 then
            local bal = sendCmd("balance", username, hash)
            if bal and bal[1] then
              print("Your current balance is "..bal[2])
            end
          elseif mode == 2 then
            write("Recipient: ")
            local recip = read()
            write("Amount: ")
            local amt = read()
            local newbal = sendCmd("transfer", username, hash, recip, amt)
            if newbal and newbal[1] then
              print(amt.." has been sent to "..recip)
              print("Your balance is now "..newbal[2])
            end
        elseif mode == 3 then print("place deposit into slot 1\n then press enter")
         ent = os.pullEvent("key")
         if ent== 28 then
           turtle.getItemDetail("minecraft:coal")
           amt = turtle.getItemCount(1)
              sendCmd("add", username, hash, amt)
         end
         turtle.dropDown()

              elseif mode == 4 then print("Amount:")
           amt=read()
           sendCmd("balance", username, hash)
           if bal >= amt then
              sendCmd("withdraw", username, hash, amt)
           elseif bal < amt then
              print("insufficient funds")
           end

        elseif mode == 5 then print("Logged off") break
          end
          print("Press any key to continue")
          os.pullEvent("key")
        end
      end
    end
    sleep(2)
  elseif mode == 3 then break
  end
end