Fix save games in Stalker New Arsenal 7.

function attach(sm)
	sm:subscribe({signal = "on_key_down", fun = this.on_key_down})
end
 
function on_key_down( key, bind )
    if
      level.main_input_receiver()
      or bind ~= key_bindings.kNA_SAVE_ON_LEVEL
    then
      return
    end
 
    local game_time = game.get_game_time()
    local day = math.floor(game_time:diffSec(getStartTime()) / 86400)
 
    local inx = jr_xvars.get_value("jr_save_on_level.index", 0)
    if inx == 99 then
        inx = 1
    else
        inx = inx + 1
    end
    jr_xvars.set_value("jr_save_on_level.index", inx)
 
    local save_name = string.format("hardsave %03d - %s. %02d", day, game.translate_string( level.name() ), inx)
 
    cmd("save", save_name)
end
 
function getStartTime()
  local d = string.explode( ".", get_string( "alife", "start_date" ), true )
  local st = game.CTime()
  st:set( tonumber( d[ 3 ] ), tonumber( d[ 2 ] ), tonumber( d[ 1 ] ), 0, 0, 0, 0 )
  local temp = game.CTime()
  temp:setHMS( 24, 0, 0 )
  return (st - temp)
end