--
-- (C) 2014-18 - ntop.org
--
local dirs = ntop.getDirs()

require "graph_utils" -- getRRDName
local os_utils = require "os_utils"
local delete_data_utils = {}
local dry_run = false

local function delete_host_fs_data(interface_id, host_info)
   if not isMacAddress(host_info["host"]) and not isIPv4(host_info["host"]) and not isIPv6(host_info["host"]) then
      -- TODO: try to find the IP address of a string
      return false
   end

   -- getRRDName automatically determines the right path both for ip and mac addresses
   local host_rrd_dir = os_utils.fixPath(dirs.workingdir .. "/" .. interface_id .. "/rrd/" .. getPathFromKey(hostinfo2hostkey(host_info)))

   if not dry_run and ntop.isdir(host_rrd_dir) then
      ntop.rmdir(host_rrd_dir)
   end

   return true
end

local function delete_host_redis_keys(interface_id, host_info)
   local serialized_k, dns_k, devnames_k, devtypes_k

   if not isMacAddress(host_info["host"]) then
      -- this is an IP address, see HOST_SERIALIZED_KEY (ntop_defines.h)
      serialized_k = string.format("ntopng.serialized_hosts.ifid_%u__%s@%d", interface_id, host_info["host"], host_info["vlan"] or "0")
      dns_k = string.format("ntopng.dns.cache.%s", host_info["host"]) -- neither vlan nor ifid implemented for the dns cache
   else
      -- is a mac address, see MAC_SERIALIED_KEY (see ntop_defines.h)
      serialized_k = string.format("ntopng.serialized_macs.ifid_%u__%s", interface_id, host_info["host"])
      devnames_k = string.format("ntopng.cache.devnames.%s", host_info["host"])
      devtypes_k = string.format("ntopng.prefs.device_types.%s", host_info["host"])
   end

   if not dry_run then
      if serialized_k then ntop.delCache(serialized_k) end
      if devnames_k   then ntop.delCache(devnames_k) end
      if devtypes_k   then ntop.delCache(devtypes_k) end
      if dns_k        then ntop.delCache(dns_k) end
   end

   return true
end

local function delete_host_mysql_flows(interface_id, host_info)
   if not ntop.getPrefs()["is_dump_flows_to_mysql_enabled"] then
      -- nothing to do..
      return true
   end

   local addr = host_info["host"]
   local vlan = host_info["vlan"] or 0
   local q

   if isIPv4(addr) then
      q = string.format("DELETE FROM %s WHERE (IP_SRC_ADDR = INET_ATON('%s') OR IP_DST_ADDR = INET_ATON('%s')) AND VLAN_ID = %u",
			"flowsv4", addr, addr, vlan)
   elseif isIPv6(addr) then
      q = string.format("DELETE FROM %s WHERE (IP_SRC_ADDR = '%s' OR IP_DST_ADDR = '%s') AND VLAN_ID = %u",
			"flowsv6", addr, addr, vlan)
   else
      return true
   end

   if not dry_run and q then
      interface.execSQLQuery(q)
   end

   return true
end

function delete_data_utils.delete_host(interface_id, host_info)
   res = {status = "ERR_DELETE_FAILED"}

   if delete_host_fs_data(interface_id, host_info) then
      if delete_host_redis_keys(interface_id, host_info) then
	 if delete_host_mysql_flows(interface_id, host_info) then
	    res = {status = "OK"}
	 end
      end
   end

   return res
end

return delete_data_utils