main.hs

module Main where
import Data.List
import System.Console.GetOpt
import System.Environment (getArgs)
import System.Exit (exitFailure)
import System.IO (hPutStrLn, stderr)
import Twitter.Search

----- Helpers -----
formatTweet :: Tweet -> String
formatTweet tweet = '@' : fromUser tweet ++ ": " ++ tweetText tweet

tweeters :: SearchResults -> [String]
tweeters = nub . sort . map fromUser . tweets

----- Handy command-line search client -----
usage = "Usage: twitsearch <OPTIONS> term [term ...]"

main = do
  args <- getArgs
  options <- parseArgs args
  results <- search options
  putStr "Tweeting about this: "
  putStrLn $ intercalate ", " $ tweeters results
  putStrLn $ take 80 $ repeat '-'
  sequence $ map putStrLn $ map formatTweet $ tweets results

options :: [OptDescr Integer]
options = [Option ['n'] ["max"] (ReqArg read "NUM") "max results (default 15)"]

parseArgs :: [String] -> IO SearchOptions
parseArgs argv =
  case getOpt' Permute options argv of
    ([count], term:terms, []              , []        ) ->
      return SearchOptions {
        resultsPerPage = count,
        searchQuery = unwords (term:terms)
        }

    ([]     , term:terms, []              , []        ) ->
      return $ basicOptions $ unwords (term:terms)

    (_      , _         , unrecog:unrecogs, _         ) ->
      do
        sequence $ map unrecognised (unrecog:unrecogs)
        errUsage

    (_      , _         , _               , errr:errrs) ->
      do
        sequence $ map putStrLn (errr:errrs)
        errUsage

    _ -> errUsage
  where
    errUsage = err $ usageInfo usage options

unrecognised :: String -> IO ()
unrecognised opt = putStrLn ("Unrecognised option " ++ opt)

err :: String -> IO a
err msg = do 
	  hPutStrLn stderr msg
	  exitFailure