import qualified Data.ByteString.Lazy as BSL
import qualified Data.ByteString.Lazy.UTF8 as BUL
import Database.TokyoCabinet.HDB
import System.Environment (getArgs)

printUsage = do
	putStrLn "Simple TokyoCabinet hash storage interface."
	putStrLn "Usage: tchcli <db file> <action> <args>"
	putStrLn "Examples: tchcli mydb.tch get mykey # gets value of mykey and prints it to STDOUT"
	putStrLn "          tchcli mydb.tch put mykey # stores data from STDIN as mykey in database"
	putStrLn "          tchcli mydb.tch putcat mykey # appends data from STDIN to mykey in database"

performTricks dbname action arg = do
	case action of
		"get" -> do
			db <- new
			open db dbname [OCREAT, OREADER]
			result <- get db (BUL.fromString arg)
			maybe (putStr "") (BSL.putStr) result
		"put" -> do
			db <- new
			open db dbname [OCREAT, OWRITER]
			put db (BUL.fromString arg) =<< BSL.getContents
			return ()
		"putcat" -> do
			db <- new
			open db dbname [OCREAT, OWRITER]
			putcat db (BUL.fromString arg) =<< BSL.getContents
			return ()
		"num" -> do
			db <- new
			open db dbname [OCREAT, OREADER]
			print =<< rnum db
		otherwise -> printUsage

main = do
	args <- getArgs
	if (length args < 3) then
		printUsage
		else do
		let [dbname, action, arg] = args
		performTricks dbname action arg