#!/usr/bin/lua

-- PID file to ensure the hoodselector isn't running parallel
local pidPath="/var/run/hoodselector.pid"

local uci = require('simple-uci').cursor()
local hoodutil = require("hoodselector.util")
local hash = require("hash")

if io.open(pidPath, "r") ~=nil then
  hoodutil.log("The hoodselector is still running.")
  os.exit(1)
else
  if io.open(pidPath, "w") ==nil then
    hoodutil.log("Can`t create pid file on "..pidPath)
    os.exit(1)
  end
end

-- Program terminating function including removing of PID file
local function exit(exc)
  if io.open(pidPath, "r") ~=nil then
    os.remove(pidPath)
  end
  os.exit(tonumber(exc))
end

-- initialization done

local function get_mesh_vpn_interface()
  local ret = {}
  if hoodutil.fastd_installed() then
    local vpnifac = uci:get('fastd', 'mesh_vpn_backbone', 'net')
    if vpnifac  ~= nil then
      vpnifac = vpnifac:gsub("%_",'-')
      table.insert(ret,vpnifac)
    else
      hoodutil.log("fastd uci config broken! abort...")
      exit(1)
    end
  end
  if hoodutil.tunneldigger_installed() then
    local vpnifac = uci:get('tunneldigger', 'mesh_vpn', 'interface')
    if vpnifac  ~= nil then
      table.insert(ret,vpnifac)
    else
      hoodutil.log("tunneldigger uci config broken! abort...")
      exit(1)
    end
  end
  return ret
end

function table.val_to_str ( v )
  if "string" == type( v ) then
    v = string.gsub( v, "\n", "\\n" )
    if string.match( string.gsub(v,"[^'\"]",""), '^"+$' ) then
      return "'" .. v .. "'"
    end
    return '"' .. string.gsub(v,'"', '\\"' ) .. '"'
  else
    return "table" == type( v ) and table.tostring( v ) or tostring( v )
  end
end

function table.key_to_str ( k )
  if "string" == type( k ) and string.match( k, "^[_%a][_%a%d]*$" ) then
    return k
  else
    return "[" .. table.val_to_str( k ) .. "]"
  end
end

function table.tostring( tbl )
  local result, done = {}, {}
  for k, v in ipairs( tbl ) do
    table.insert( result, table.val_to_str( v ) )
    done[ k ] = true
  end
  for k, v in pairs( tbl ) do
    if not done[ k ] then
      table.insert( result, table.key_to_str( k ) .. "=" .. table.val_to_str( v ) )
    end
  end
  return "{" .. table.concat( result, "," ) .. "}"
end


-- INITIALIZE AND PREPARE DATA --
-- read hoodfile...
local jhood = hoodutil.get_domains()

-- get defaul hood
local defaultHood = hoodutil.getDefaultHood(jhood)

-- VPN MODE
-- If we have a VPN connection then we will try to get the routers location and
-- select the hood coresponding to our location.
-- If no hood for the location has been defined, we will select
-- the default hood.
-- If we can not get our routers location, we will continure to next mode.
if hoodutil.directVPN(get_mesh_vpn_interface()) then
  io.stdout:write('VPN connection found.\n')
  local geo = hoodutil.getGeolocation()
  if geo.lat ~= nil and geo.lon ~= nil then
    io.stdout:write('Position found.\n')
    local geoHood = hoodutil.getHoodByGeo(jhood, geo)
    if geoHood ~= nil then
      if hoodutil.set_hoodconfig(geoHood) then
        hoodutil.restart_services() -- TMP solution
        io.stdout:write('Hood set by VPN mode.\n')
      end
      exit(0)
    end
    io.stdout:write('No hood has been defined for current position.\n')
    if hoodutil.set_hoodconfig(defaultHood) then
      hoodutil.restart_services() -- TMP solution
      io.stdout:write('Hood set by VPN mode.\n')
    end
    exit(0)
  else
    -- The hoodselector should continure with next states because thier can be other
    -- VPN routers in the local mesh network which provides a possition and therfore
    -- have set a geo base hood.
    io.stdout:write('No position found\n')
  end
else
  io.stdout:write('No VPN connection found\n')
end

--[[
-- GATEWAY MODE
-- If a node have batman-adv GWs ensure config is validate to current hood.
-- Furthermore is a node is connected to a neigbour hood check if its geo base hood avalable.
local gw_intf = hoodutil.get_batman_GW_interface()
if gw_intf ~= nil then
  io.stdout:write('Batman gateways found\n')
  -- We have to verify if the currend applyed setting
  -- return currend applyed hood if source gw_intf a wifi interface
  -- we have to check the hood explecit bw wifi source besause the
  -- scan mode can apply an unknown hood by adapting the mesh id or
  -- bssid with deaktivated VPNs(in case if a router will get a VPN
  -- connection afterwards).
  local currentHood = hoodutil.getHoodByRadio(gw_intf, jhood)
  if currentHood ~= nil then
    print("DEBUG: currentHood ~= nil")
    -- Now we need check if the current seclected hood our geo base hood, otherwise search for
    -- our geo base hood in the local network ENV
    --check if hood inside geo pos
    local geo = hoodutil.getGeolocation()
    if geo.lat ~= nil and geo.lon ~= nil then
      io.stdout:write('Position found.\n')
      local geoHood = hoodutil.getHoodByGeo(jhood, geo)
      if geoHood ~= nil then
        print("DEBUG: geoHood ~= nil")
        if string.format(hash.md5(table.tostring(currentHood))) ~=
        string.format(hash.md5(table.tostring(geoHood))) then
          io.stdout:write('Geo hood and current applyed hood are not equal, do wifi scan...\n')
          local sortedWlanList = hoodutil.wlan_list_sorted()
          for i=#sortedWlanList,1,-1 do
            -- Filter all wifis whicht does not match the geo base hood
--            if h.domain.wifi24 ~= nil then
--              if h.domain.wifi24.ibss ~= nil then
               print("foo")
--             end
--           end
         end
        end
      end
    end
  end

454        if geoHood ~= nil then
455          if string.format(hash.md5(table.tostring(bssidHood))) ~=
               string.format(hash.md5(table.tostring(geoHood))) then
456            io.stdout:write('Geo hood and bssid hood are not equal, do wifi scan...\n')
457            local sortedWlanList = hoodutil.wlan_list_sorted(radios, mesh_prefix)
458            for i=#sortedWlanList,1,-1 do
459              if(string.lower(geoHood.bssid) ~= string.lower(sortedWlanList[i].bssid)) then
460               table.remove(sortedWlanList, i)
461              end
462            end
463            if next(sortedWlanList) then
464              io.stdout:write('Try to switch back in our real hood!\n')
465              io.stdout:write('After filtering we will test the following wireless networks:\n')
466              for _, network in pairs(sortedWlanList) do
467               print(network["quality"].."\t"..network["frequency"].."\t"..network["bssid"].."\t"..network["ssid"])
468              end
469              io.stdout:write("Prepare configuration for testing wireless networks...\n")
470              local bssid = hoodutil.test_batman_mesh_networks(sortedWlanList, mesh_prefix)
471              hoodutil.wireless_restart()
472              io.stdout:write("Finished testing wireless networks, restored previous configuration\n")
473              if bssid ~= nil then
474               set_hoodconfig(geoHood, mesh_prefix, radios)
475               hoodutil.vpn_enable()
476               hoodutil.vpn_start()
477               io.stdout:write('Set Geo Hood by Gateway mode\n')
478               write_molwm(geoHood, radios)
479               exit(0)
480              else
481               io.stdout:write('No neighboring freifunk batman advanced mesh found.\n')
482              end
483            else
484              io.stdout:write('No networks left after filtering!\n')
485            end --end next(sortedWlanList)
486          else
487            io.stdout:write('Geo hood are equal to bssid hood no wifi scan necessary.\n')
488          end --end bssidHood ~= geoHood
489        else
490          io.stdout:write('No hood has been defined for current position.\n')
491        end --end geoHood ~= nil
492       else
493        io.stdout:write('No position found.\n')
494       end --end geo.lat ~= nil and geo.lon ~= nil
495       set_hoodconfig(bssidHood, mesh_prefix, radios)
496       io.stdout:write('Hood set by batmanHasGateway mode, GW source is wifi\n')
497       write_molwm(bssidHood,radios)
498       exit(0)
499     end --end bssidHood ~= nil
500
501     -- mesh lan or wan interface
502     if hoodutil.mesh_lan_wan(gw_intf[1]) then
503       -- if mesh_lan/wan try to get hood by selected bssid of neightbour vpnRouters
504       local neighbourBssid = hoodutil.molw_get_bssid(gw_intf)
505       if neighbourBssid ~= nil then
506         bssidHood = hoodutil.gethoodByBssid(jhood, neighbourBssid)
507         if bssidHood ~= nil then
508           set_hoodconfig(bssidHood, mesh_prefix, radios)
509           io.stdout:write('Hood set by batmanHasGateway mode, GW source is mesh on lan/wan\n')
510           molwmtable["md5hash"] = "\"" .. string.format(hash.md5(table.tostring(bssidHood))) .. "\""
511           molwmtable["hoodname"] = "\"" .. bssidHood["name"] .. "\""
512           molwmtable["bssid"] = "\"" .. bssidHood["bssid"] .. "\""
513           molwm_to_file()
514           exit(0)
515         end
516       end
517     end]]
--end -- end gw_intf

-- SCAN MODE
if next(hoodutil.getWifiDevices()) then
  print("Entering SCAN MODE ...")
  -- check if there exist a neighbouring freifunk batman advanced mesh
  -- network with an active connection to a batman advanced gateway
  local sortedWlanList = hoodutil.wlan_list_sorted()
  if next(sortedWlanList) then
    local ID = hoodutil.get_batman_mesh_network(sortedWlanList, defaultHood)
    if ID ~= nil then
      local scanHood = nil
      if ID.method == "ibss" then
        io.stdout:write("Neighoring freifunk batman advanced mesh with Bssid: "..ID.bssid.." found\n")
        scanHood = hoodutil.gethoodByBssid(jhood, ID.bssid)
      end
      if ID.method == "11s" then
        io.stdout:write("Neighoring freifunk batman advanced mesh with meshid: "..ID.meshid.." found\n")
        scanHood = hoodutil.gethoodByMeshID(jhood, ID.meshid)
      end
      if scanHood ~= nil then
        if hoodutil.set_hoodconfig(scanHood) then
          hoodutil.restart_services() -- TMP solution
          io.stdout:write('Hood set by scan mode\n')
        end
        exit(0)
      end

    -- if the wifi ID does not corespond to any hood, we disable all VPN and
    -- just establish a wireless connection to the coresponding mesh. Furthermore
    -- we set a unknown VXLAN ID to signalisize neibouring mesh on LAN/WAN nodes
    -- that we have a gateway conection but does not know to which hood it is coresponding.
    io.stdout:write("No hood has been found for this mesh ID\n")
    --hoodutil.vpn_stop()
    --hoodutil.vpn_disable()
    --TBD
    -- some idea was to collect neigbouhood informations like VXLAN ID over respondd
    end
  end
end

--Radio less mode
-- TBD

-- DEFAULT-HOOD MODE
-- If we do NOT have a VPN connection and no other freifunk mesh nodes found in our network ENV
-- then we set the default hood.
io.stdout:write("ENV does not give enough information\n")
if hoodutil.set_hoodconfig(defaultHood) then
  hoodutil.restart_services() -- TMP solution
  io.stdout:write('Hood set by default-hood mode.\n')
end
exit(0)