import Control.Monad
import Control.Concurrent
import System.Random

import Control.Concurrent.Pool

second = 1000000

tester :: Int -> Int -> IO Int
tester n m = do
  th <- myThreadId
  putStrLn $ "Starting task #" ++ show n ++ " in [" ++ show th ++ "] for " ++ show m ++ " ticks."
  forM_ [1..m] $ \k -> do
    putStrLn $ "Task " ++ show n ++ ": " ++ show k ++ "..."
--     threadDelay second
  putStrLn $ "Task " ++ show n ++ ": done."
  return n

resultCollector :: Integer -> Int -> IO ()
resultCollector task n =
  putStrLn $ "Task #" ++ show task ++ " ended with result: " ++ show n

main = do
  pool <- newPool 1 True
  forM_ [1..1000] $ \k -> do
    timeout <- randomRIO (1,10)
    queue pool (tester k timeout) ()
  noMoreTasks pool
  forkIO $ resultsReader pool resultCollector
  waitFor pool
  terminatePool pool