json = require "json"

_config = {}

function _config.read(file)

  local file = file or "/opt/squid-auth-helper/config.json"
  local f = assert(io.open(file))
  local cfg = json.decode(f:read("*all"))

  _config.pmap = cfg["portmap"] or {}  

  _config.ident_timeout = 2
  _config.ident_default = nil

  if cfg["ident"] then
    _config.ident_timeout = cfg["ident"]["timeout"] or _config.ident_timeout
    _config.ident_default = cfg["ident"]["default"] or _config.ident_default
  end

  _config.ipmap = {}
  _config.macmap = {}
  
  if cfg["hosts"] then
    if cfg["hosts"]["ip"] then
      for k, v in pairs(cfg["hosts"]["ip"]) do
        local k, n = string.gsub(k, "%.", "%%.")
        local k, n = string.gsub(k,"%*",".*")
        _config.ipmap["^"..k.."$"] = v 
      end
    end
    if cfg["hosts"]["mac"] then
      for k, v in pairs(cfg["hosts"]["mac"]) do
        local k, n = string.gsub(k,"%*",".*")
        _config.macmap["^"..k.."$"] = v 
      end
    end 
  end

  _config.arp_ttl = 60

  if cfg["arp-ttl"] then
    _config.arp_ttl = tonumber(cfg["arp-ttl"])
  end
  
end

function _config.map_port(port)
  return _config.pmap[tostring(port)] or port
end

function _config.map_ip(ip)
  for k,v in pairs(_config.ipmap) do
    if string.match(ip,k) then
      return v
    end  
  end
  return nil
end

function _config.map_mac(mac)
  for k,v in pairs(_config.macmap) do
    if string.match(mac,k) then
      return v
    end  
  end
  return nil
end

return _config