dbus-0.10.1: examples/introspect.hs

{-# LANGUAGE OverloadedStrings #-}

-- Copyright (C) 2009-2011 John Millikin <jmillikin@gmail.com>
-- 
-- This program is free software: you can redistribute it and/or modify
-- it under the terms of the GNU General Public License as published by
-- the Free Software Foundation, either version 3 of the License, or
-- any later version.
-- 
-- This program is distributed in the hope that it will be useful,
-- but WITHOUT ANY WARRANTY; without even the implied warranty of
-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-- GNU General Public License for more details.
-- 
-- You should have received a copy of the GNU General Public License
-- along with this program.  If not, see <http://www.gnu.org/licenses/>.

module Main (main) where

import           Control.Monad (when)
import           Data.String (fromString)
import qualified Data.Text
import           System.Environment (getArgs, getProgName)
import           System.Exit (exitFailure)
import           System.IO (hPutStrLn, stderr)

import           DBus
import           DBus.Client
import qualified DBus.Introspection as I

main :: IO ()
main = do
	args <- getArgs
	(service, path) <- case args of
		a1:a2:_ -> return (fromString a1, fromString a2)
		_ -> do
			name <- getProgName
			hPutStrLn stderr ("Usage: " ++ name ++ " <service> <path>")
			exitFailure
	client <- connectSession
	printObj (introspect client service) path

introspect :: Client -> BusName -> ObjectPath -> IO I.Object
introspect client service path = do
	reply <- call_ client (methodCall path "org.freedesktop.DBus.Introspectable" "Introspect")
		{ methodCallDestination = Just service
		}
	let Just xml = fromVariant (methodReturnBody reply !! 0)
	case I.parseXML path xml of
		Just info -> return info
		Nothing -> error ("Invalid introspection XML: " ++ show xml)

-- most of this stuff is just boring text formatting

printObj :: (ObjectPath -> IO I.Object) -> ObjectPath -> IO ()
printObj get path = do
	obj <- get path
	putStrLn (formatObjectPath path)
	mapM_ printIface (I.objectInterfaces obj)
	putStrLn ""
	mapM_ (printObj get) [I.objectPath x | x <- I.objectChildren obj]

printIface :: I.Interface -> IO ()
printIface iface = do
	putStr "    "
	putStrLn (formatInterfaceName (I.interfaceName iface))
	
	mapM_ printMethod (I.interfaceMethods iface)
	mapM_ printSignal (I.interfaceSignals iface)
	mapM_ printProperty (I.interfaceProperties iface)
	putStrLn ""

printMethod :: I.Method -> IO ()
printMethod method = do
	putStr "        method "
	putStrLn (formatMemberName (I.methodName method))
	mapM_ printMethodArg (I.methodArgs method)

printMethodArg :: I.MethodArg -> IO ()
printMethodArg arg = do
	let dir = case I.methodArgDirection arg of
		d | d == I.directionIn -> "IN "
		d | d == I.directionOut -> "OUT"
		_ -> "   "
	putStr ("            [" ++ dir ++ " ")
	putStr (show (formatSignature (signature_ [I.methodArgType arg])) ++ "] ")
	putStrLn (I.methodArgName arg)

printSignal :: I.Signal -> IO ()
printSignal sig = do
	putStr "        signal "
	putStrLn (formatMemberName (I.signalName sig))
	mapM_ printSignalArg (I.signalArgs sig)

printSignalArg :: I.SignalArg -> IO ()
printSignalArg arg = do
	putStr "            ["
	putStr (show (formatSignature (signature_ [I.signalArgType arg])) ++ "] ")
	putStrLn (I.signalArgName arg)

printProperty :: I.Property -> IO ()
printProperty prop = do
	putStr "        property "
	putStr (show (formatSignature (signature_ [I.propertyType prop])) ++ " ")
	putStrLn (I.propertyName prop)
	
	putStr "            "
	when (I.propertyRead prop) (putStr "Read")
	when (I.propertyWrite prop) (putStr "Write")
	putStrLn ""