local Config = require('config')

local config = { }

local Security = { }

function Security.verifyPassword(password)
  Config.load('os', config)
  return config.password and password == config.password
end

function Security.hasPassword()
  return not not config.password
end

function Security.getSecretKey()
  Config.load('os', config)
  if not config.secretKey then
    config.secretKey = math.random(100000, 999999)
    Config.update('os', config)
  end
  return config.secretKey
end

function Security.getPublicKey()

  local exchange = {
    base = 11,
    primeMod = 625210769
  }

  local function modexp(base, exponent, modulo)
    local remainder = base

    for _ = 1, exponent-1 do
      remainder = remainder * remainder
      if remainder >= modulo then
        remainder = remainder % modulo
      end
    end

    return remainder
  end

  local secretKey = Security.getSecretKey()
  return modexp(exchange.base, secretKey, exchange.primeMod)
end

function Security.updatePassword(password)
  Config.load('os', config)
  config.password = password
  Config.update('os', config)
end

function Security.getPassword()
  Config.load('os', config)
  return config.password
end

return Security