--
-- (C) 2017-21 - ntop.org
--

local dirs = ntop.getDirs()
package.path = dirs.installdir .. "/scripts/lua/modules/pools/?.lua;" .. package.path

local pools = require "pools"
local host_pools = require "host_pools"

-- Retrieve the info from the pool
local pool_info = ntop.getDropPoolInfo()

local drop_host_pool_utils = {}
local drop_host_pool_id

-- ############################################

function drop_host_pool_utils.check_pre_banned_hosts_to_add()
   local queue_name = "ntopng.cache.tmp_add_host_list"
   local host_pool = nil
   local changed = false

   while(true) do
      local elem = ntop.lpopCache(queue_name)

      if(elem == nil) then
	      break
      else
	      if(host_pool == nil) then 
            host_pool = host_pools:create() 
         end

         -- io.write("Adding "..elem.." to pool ["..pools.DROP_HOST_POOL_NAME.."]\n")
         local blocked_hosts_pool_name = pools.DROP_HOST_POOL_NAME
         local all_pools = host_pool:get_all_pools()
         
         -- Check the existance of the pool   
         for _, value in pairs(all_pools) do
            if value["name"] == blocked_hosts_pool_name then
               local res, err = host_pool:bind_member(elem, value["pool_id"])
               changed = true
               break
            end
         end	 
      end
   end

   -- Read rules from configured pools and policies
   -- and push rules to the nProbe listeners
   if(changed) then
      if ntop.isPro() then
         package.path = dirs.installdir .. "/pro/scripts/lua/modules/?.lua;" .. package.path
         local policy_utils = require "policy_utils"
         
         local rsp = policy_utils.get_ips_rules()
         if(rsp ~= nil) then
            ntop.broadcastIPSMessage(rsp)
         end
      end
   end
end

-- ############################################

-- This function checks if the are banned hosts that need to be unbanned

function drop_host_pool_utils.check_periodic_hosts_list()
   -- Check the list length
   local list_len = ntop.llenCache(pool_info.list_key)
   local changed = false
   
   if list_len == 0 then
      return
   end     

   -- Retrieve the pool
   local blocked_hosts_pool_id = -2
   -- Get the pool name
   local blocked_hosts_pool_name = pools.DROP_HOST_POOL_NAME
   local blocked_hosts_pool_members = {}
   local host_pool = host_pools:create()
   local all_pools = host_pool:get_all_pools()
   
   -- Check the existance of the pool   
   for _, value in pairs(all_pools) do
      if value["name"] == blocked_hosts_pool_name then
            blocked_hosts_pool_id = value["pool_id"]
            blocked_hosts_pool_members = value.members
            goto continue
      end
   end
   
   ::continue::
   
   -- Check the hosts inside the list
   while list_len > 0 do
      local data = ntop.lpopCache(pool_info.list_key)
      local curr_time = os.time()
        local host
        local time
	
        host, time = data:match("(%w+)_(%w+)")
	
        -- The host needs to be unbanned
        if curr_time >= tonumber(time) + pool_info.expiration_time then
            for i, value in pairs(blocked_hosts_pool_members) do
	       -- Member found, remove it
	       if string.find(value, host) then
		  host_pool:bind_member(value, 0)
		  changed = true
		  goto continue_check
	       end
            end        
        else
	   -- The host needs to be added again at the start of the list (ordered by time)
	   ntop.lpushCache(pool_info.list_key, data)
	   goto policy_changed
        end
	
        ::continue_check::
        list_len = list_len - 1
   end 

   ::policy_changed::
   -- Read rules from configured pools and policies
   -- and push rules to the nProbe listeners
   if(changed) then
      if ntop.isPro() then
	 package.path = dirs.installdir .. "/pro/scripts/lua/modules/?.lua;" .. package.path
	 local policy_utils = require "policy_utils"
	 
	 local rsp = policy_utils.get_ips_rules()
	 if(rsp ~= nil) then
	     ntop.broadcastIPSMessage(rsp)
	 end
      end
   end
end 

-- ############################################

return drop_host_pool_utils