#!/usr/bin/lua

local util = require("luci.util")
local json = require("luci.json")
local config = require 'gluon.sites'
local uci = require('luci.model.uci').cursor()
local site = require 'gluon.site_config'

function is_site_valid(site)
  for _, tmp in pairs(config) do
    if tmp.site_code == site then
      return true
    end
  end
  return false
end

function set_currentsite(site)
  if site and is_site_valid(site) then
    uci:set('currentsite', 'current', 'name', site)
    uci:save('currentsite')
    uci:commit('currentsite')
    return true
  end
  return false
end

function neighbours(ifname)
  local info = util.exec("gluon-neighbour-info -d ff02::2:1001 -p 1001 -r nodeinfo -t 2 -i " .. ifname)
  local macs = {}
  for _, line in ipairs(util.split(info)) do
    local data = json.decode(line)
    if data and data["network"] then
      local mac = data["network"]["mac"]
      if mac then
        macs[mac] = data
      end
    end
  end

  return macs
end

function get_neighbour_site()
  local interfaces = util.split(util.trim(util.exec("batctl if | grep active | grep -v mesh-vpn | cut -d':' -f1")))
  for _, ifname in ipairs(interfaces) do
    local macs = neighbours(ifname)
    for _, node in pairs(macs) do
      if node["system"] then
        local node_site = node["system"]["site_code"]
        if node_site and is_site_valid(node_site) then
          return node_site
        end
      end
    end
  end

  return nil
end

local currentsite = uci:get('currentsite', 'current', 'name')
local configured = is_site_valid(currentsite)

if configured == false then
  currentsite = get_neighbour_site()
  configured = set_currentsite(currentsite)
end

if configured then
  os.execute("rm -f /lib/gluon/cron/ffho-site-auto-select >/dev/null 2>&1")
  if site.site_code ~= currentsite then
    os.execute("/lib/gluon/site-select/site-upgrade >/dev/null 2>&1")
    os.execute("reboot >/dev/null 2>&1")
  end
end