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libmpd (empty) → 0.1.2

raw patch · 9 files changed

+1720/−0 lines, 9 filesdep +basedep +mtldep +networkbuild-type:Customsetup-changed

Dependencies added: base, mtl, network

Files

+ ChangeLog view
@@ -0,0 +1,8 @@+* v0.1.2, 2007-09-29+	- Changed name to libmpd.++* v0.1.1, 2007-09-28+	- Missing files added to the source distribution.++* v0.1, 2007-09-28+	- Initial public release.
+ LICENSE view
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+ Network/MPD.hs view
@@ -0,0 +1,73 @@+{-+    libmpd for Haskell, an MPD client library.+    Copyright (C) 2005-2007  Ben Sinclair <bsinclai@turing.une.edu.au>++    This library is free software; you can redistribute it and/or+    modify it under the terms of the GNU Lesser General Public+    License as published by the Free Software Foundation; either+    version 2.1 of the License, or (at your option) any later version.++    This library 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+    Lesser General Public License for more details.++    You should have received a copy of the GNU Lesser General Public+    License along with this library; if not, write to the Free Software+    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA+-}++-- | Module    : Network.MPD+-- Copyright   : (c) Ben Sinclair 2005-2007+-- License     : LGPL+-- Maintainer  : bsinclai@turing.une.edu.au+-- Stability   : alpha+-- Portability : Haskell 98+--+-- MPD client library.++module Network.MPD (+    -- * Basic data types+    MPD, MPDError(..), ACKType(..), Response,+    module Network.MPD.Commands,+    -- * Connections+    withMPD, withMPDEx,+    -- * Misc.+    kill, throwMPD, catchMPD+    ) where++import Network.MPD.Commands+import Network.MPD.Prim++import Control.Monad (liftM)+import Data.Maybe (listToMaybe)+import Data.IORef (newIORef, atomicModifyIORef)+import System.Environment (getEnv)+import System.IO+import System.IO.Error (isDoesNotExistError, ioError)++-- | Run an MPD action using localhost:6600 as the default host:port,+-- or whatever is found in the environment variables MPD_HOST and+-- MPD_PORT. If MPD_HOST is of the form \"password\@host\" then the+-- password will be supplied as well.+withMPD :: MPD a -> IO (Response a)+withMPD m = do+    port <- liftM read (getEnvDefault "MPD_PORT" "6600")+    (pw,host) <- liftM (break (== '@')) (getEnvDefault "MPD_HOST" "localhost")+    let (host',pw') = if null host then (pw,host) else (drop 1 host,pw)+    pwGen <- mkPasswordGen [pw']+    withMPDEx host' port pwGen m+    where+        getEnvDefault x dflt =+            catch (getEnv x) (\e -> if isDoesNotExistError e+                                    then return dflt else ioError e)++-- | Create an action that produces passwords for a connection. You+-- can pass these to 'withMPDEx' and it will use them to get passwords+-- to send to the server until one works or it runs out of them.+--+-- > do gen <- mkPasswordGen ["password1", "password2"]+-- >    withMPDEx "localhost" 6600 gen (update [])+mkPasswordGen :: [String] -> IO (IO (Maybe String))+mkPasswordGen = liftM f . newIORef+    where f = flip atomicModifyIORef $ \xs -> (drop 1 xs, listToMaybe xs)
+ Network/MPD/Commands.hs view
@@ -0,0 +1,789 @@+{-+    libmpd for Haskell, an MPD client library.+    Copyright (C) 2005-2007  Ben Sinclair <bsinclai@turing.une.edu.au>++    This library is free software; you can redistribute it and/or+    modify it under the terms of the GNU Lesser General Public+    License as published by the Free Software Foundation; either+    version 2.1 of the License, or (at your option) any later version.++    This library 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+    Lesser General Public License for more details.++    You should have received a copy of the GNU Lesser General Public+    License along with this library; if not, write to the Free Software+    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA+-}++-- | Module    : Network.MPD.Commands+-- Copyright   : (c) Ben Sinclair 2005-2007+-- License     : LGPL+-- Maintainer  : bsinclai@turing.une.edu.au+-- Stability   : alpha+-- Portability : Haskell 98+--+-- Interface to the user commands supported by MPD.++module Network.MPD.Commands (+    -- * Command related data types+    State(..), Status(..), Stats(..),+    Device(..),+    Query(..), Meta(..),+    Artist, Album, Title, Seconds, PLIndex(..),+    Song(..), Count(..),++    -- * Admin commands+    disableoutput, enableoutput, outputs, update,++    -- * Database commands+    find, list, listAll, listAllinfo, lsinfo, search, count,++    -- * Playlist commands+    -- $playlist+    add, add_, addid, clear, currentSong, delete, load, move,+    playlistinfo, listplaylist, listplaylistinfo, playlist, plchanges,+    plchangesposid, playlistfind, playlistsearch, rm, rename, save, shuffle,+    swap,++    -- * Playback commands+    crossfade, next, pause, play, previous, random, repeat, seek, setVolume,+    volume, stop,++    -- * Miscellaneous commands+    clearerror, close, commands, notcommands, tagtypes, urlhandlers, password,+    ping, reconnect, stats, status,++    -- * Extensions\/shortcuts+    addMany, deleteMany, crop, prune, lsdirs, lsfiles, lsplaylists, findArtist,+    findAlbum, findTitle, listArtists, listAlbums, listAlbum, searchArtist,+    searchAlbum, searchTitle, getPlaylist, toggle, updateid+    ) where++import Network.MPD.Prim++import Control.Monad (liftM, unless)+import Prelude hiding (repeat)+import Data.List (findIndex)+import Data.Maybe++--+-- Data types+--++type Artist  = String+type Album   = String+type Title   = String+type Seconds = Integer++-- | Available metadata types\/scope modifiers, used for searching the+-- database for entries with certain metadata values.+data Meta = Artist | Album | Title | Track | Name | Genre | Date+    | Composer | Performer | Disc | Any | Filename++instance Show Meta where+    show Artist    = "Artist"+    show Album     = "Album"+    show Title     = "Title"+    show Track     = "Track"+    show Name      = "Name"+    show Genre     = "Genre"+    show Date      = "Date"+    show Composer  = "Composer"+    show Performer = "Performer"+    show Disc      = "Disc"+    show Any       = "Any"+    show Filename  = "Filename"++-- | A query is composed of a scope modifier and a query string.+data Query = Query Meta String  -- ^ Simple query.+           | MultiQuery [Query] -- ^ Query with multiple conditions.++instance Show Query where+    show (Query meta query) = show meta ++ " " ++ show query+    show (MultiQuery xs)    = show xs+    showList xs _ = unwords $ map show xs++-- | Represents a song's playlist index.+data PLIndex = Pos Integer -- ^ A playlist position index (starting from 0)+             | ID Integer  -- ^ A playlist ID number that more robustly+                           --   identifies a song.+    deriving Show++-- | Represents the different playback states.+data State = Playing+           | Stopped+           | Paused+    deriving (Show, Eq)++-- | Container for MPD status.+data Status =+    Status { stState :: State+             -- | A percentage (0-100)+           , stVolume          :: Int+           , stRepeat          :: Bool+           , stRandom          :: Bool+             -- | A value that is incremented by the server every time the+             --   playlist changes.+           , stPlaylistVersion :: Integer+           , stPlaylistLength  :: Integer+             -- | Current song's position in the playlist.+           , stSongPos         :: Maybe PLIndex+             -- | Current song's playlist ID.+           , stSongID          :: Maybe PLIndex+             -- | Time elapsed\/total time.+           , stTime            :: (Seconds, Seconds)+             -- | Bitrate (in kilobytes per second) of playing song (if any).+           , stBitrate         :: Int+             -- | Crossfade time.+           , stXFadeWidth      :: Seconds+             -- | Samplerate\/bits\/channels for the chosen output device+             --   (see mpd.conf).+           , stAudio           :: (Int, Int, Int)+             -- | Job ID of currently running update (if any).+           , stUpdatingDb      :: Integer+             -- | Last error message (if any).+           , stError           :: String }+    deriving Show++-- | Container for database statistics.+data Stats =+    Stats { stsArtists    :: Integer -- ^ Number of artists.+          , stsAlbums     :: Integer -- ^ Number of albums.+          , stsSongs      :: Integer -- ^ Number of songs.+          , stsUptime     :: Seconds -- ^ Daemon uptime in seconds.+          , stsPlaytime   :: Seconds -- ^ Total playing time.+          , stsDbPlaytime :: Seconds -- ^ Total play time of all the songs in+                                     --   the database.+          , stsDbUpdate   :: Integer -- ^ Last database update in UNIX time.+          }+    deriving Show++-- | Represents a single song item.+data Song =+    Song { sgArtist, sgAlbum, sgTitle, sgFilePath, sgGenre, sgName, sgComposer+         , sgPerformer :: String+         , sgLength    :: Seconds       -- ^ Length in seconds+         , sgDate      :: Int           -- ^ Year+         , sgTrack     :: (Int, Int)    -- ^ Track number\/total tracks+         , sgDisc      :: (Int, Int)    -- ^ Position in set\/total in set+         , sgIndex     :: Maybe PLIndex }+    deriving Show++-- Avoid the need for writing a proper 'elem' for use in 'prune'.+instance Eq Song where+    (==) x y = sgFilePath x == sgFilePath y++-- | Represents the result of running 'count'.+data Count =+    Count { cSongs    :: Integer -- ^ Number of songs matching the query+          , cPlaytime :: Seconds -- ^ Total play time of matching songs+          }+    deriving Show++-- | Represents an output device.+data Device =+    Device { dOutputID      :: Int    -- ^ Output's ID number+           , dOutputName    :: String -- ^ Output's name as defined in the MPD+                                      --   configuration file+           , dOutputEnabled :: Bool }+    deriving Show++class Parsable a where+    parse :: [String] -> a++parseResponse :: (Parsable a) => String -> MPD a+parseResponse = liftM parse . getResponse++instance Parsable () where+    parse = const ()++instance Parsable [String] where+    parse = takeValues++--+-- Admin commands+--++-- | Turn off an output device.+disableoutput :: Int -> MPD ()+disableoutput = parseResponse . ("disableoutput " ++) . show++-- | Turn on an output device.+enableoutput :: Int -> MPD ()+enableoutput = getResponse_ . ("enableoutput " ++) . show++-- | Retrieve information for all output devices.+outputs :: MPD [Device]+outputs = liftM (map takeDevInfo . splitGroups . kvise)+    (getResponse "outputs")+    where+        takeDevInfo xs = Device {+            dOutputID      = takeNum "outputid" xs,+            dOutputName    = takeString "outputname" xs,+            dOutputEnabled = takeBool "outputenabled" xs+            }++-- | Update the server's database.+update :: [String] -- ^ Optionally specify a list of paths+       -> MPD ()+update  [] = getResponse_ "update"+update [x] = getResponse_ ("update " ++ show x)+update  xs = getResponses (map (("update " ++) . show) xs) >> return ()++--+-- Database commands+--++-- | List all metadata of metadata (sic).+list :: Meta -- ^ Metadata to list+     -> Maybe Query -> MPD [String]+list mtype query = liftM takeValues (getResponse cmd)+    where cmd = "list " ++ show mtype ++ maybe "" ((" "++) . show) query++-- | Non-recursively list the contents of a database directory.+lsinfo :: Maybe String -- ^ Optionally specify a path.+       -> MPD [Either String Song]+lsinfo path = do+    (dirs,_,songs) <- liftM takeEntries+                      (getResponse ("lsinfo " ++ maybe "" show path))+    return (map Left dirs ++ map Right songs)++-- | List the songs (without metadata) in a database directory recursively.+listAll :: Maybe String -> MPD [String]+listAll path = liftM (map snd . filter ((== "file") . fst) . kvise)+                     (getResponse ("listall " ++ maybe "" show path))++-- | Recursive 'lsinfo'.+listAllinfo :: Maybe String -- ^ Optionally specify a path+            -> MPD [Either String Song]+listAllinfo path = do+    (dirs,_,songs) <- liftM takeEntries+                      (getResponse ("listallinfo " ++ maybe "" show path))+    return (map Left dirs ++ map Right songs)++-- | Search the database for entries exactly matching a query.+find :: Query -> MPD [Song]+find query = liftM takeSongs (getResponse ("find " ++ show query))++-- | Search the database using case insensitive matching.+search :: Query -> MPD [Song]+search query = liftM takeSongs (getResponse ("search " ++ show query))++-- | Count the number of entries matching a query.+count :: Query -> MPD Count+count query = liftM (takeCountInfo . kvise)+                    (getResponse ("count " ++ show query))+    where takeCountInfo xs = Count { cSongs    = takeNum "songs" xs,+                                     cPlaytime = takeNum "playtime" xs }++--+-- Playlist commands+--+-- $playlist+-- Unless otherwise noted all playlist commands operate on the current+-- playlist.++-- | Like 'add', but returns a playlist id.+addid :: String -> MPD Integer+addid x =+    liftM (read . snd . head . kvise) (getResponse ("addid " ++ show x))++-- | Like 'add_' but returns a list of the files added.+add :: Maybe String -> String -> MPD [String]+add plname x = add_ plname x >> listAll (Just x)++-- | Add a song (or a whole directory) to a playlist.+-- Adds to current if no playlist is specified.+-- Will create a new playlist if the one specified does not already exist.+add_ :: Maybe String -- ^ Optionally specify a playlist to operate on+     -> String -> MPD ()+add_ Nothing       = getResponse_ . ("add " ++) . show+add_ (Just plname) = getResponse_ .+                     (("playlistadd " ++ show plname ++ " ") ++) . show++-- | Clear a playlist. Clears current playlist if no playlist is specified.+-- If the specified playlist does not exist, it will be created.+clear :: Maybe String -- ^ Optional name of a playlist to clear.+      -> MPD ()+clear = getResponse_ . maybe "clear" (("playlistclear " ++) . show)++-- | Remove a song from a playlist.+-- If no playlist is specified, current playlist is used.+-- Note that a playlist position ('Pos') is required when operating on+-- playlists other than the current.+delete :: Maybe String -- ^ Optionally specify a playlist to operate on+       -> PLIndex -> MPD ()+delete Nothing (Pos x) = getResponse_ ("delete " ++ show x)+delete Nothing (ID x) = getResponse_ ("deleteid " ++ show x)+delete (Just plname) (Pos x) =+    getResponse_ ("playlistdelete " ++ show plname ++ " " ++ show x)+delete _ _ = fail "'delete' within a playlist doesn't accept a playlist ID"++-- | Load an existing playlist.+load :: String -> MPD ()+load = getResponse_ . ("load " ++) . show++-- | Move a song to a given position.+-- Note that a playlist position ('Pos') is required when operating on+-- playlists other than the current.+move :: Maybe String -- ^ Optionally specify a playlist to operate on+     -> PLIndex -> Integer -> MPD ()+move Nothing (Pos from) to =+    getResponse_ ("move " ++ show from ++ " " ++ show to)+move Nothing (ID from) to =+    getResponse_ ("moveid " ++ show from ++ " " ++ show to)+move (Just plname) (Pos from) to =+    getResponse_ ("playlistmove " ++ show plname ++ " " ++ show from +++                       " " ++ show to)+move _ _ _ = fail "'move' within a playlist doesn't accept a playlist ID"++-- | Delete existing playlist.+rm :: String -> MPD ()+rm = getResponse_ . ("rm " ++) . show++-- | Rename an existing playlist.+rename :: String -- ^ Name of playlist to be renamed+       -> String -- ^ New playlist name+       -> MPD ()+rename plname new =+    getResponse_ ("rename " ++ show plname ++ " " ++ show new)++-- | Save the current playlist.+save :: String -> MPD ()+save = getResponse_ . ("save " ++) . show++-- | Swap the positions of two songs.+-- Note that the positions must be of the same type, i.e. mixing 'Pos' and 'ID'+-- will result in a no-op.+swap :: PLIndex -> PLIndex -> MPD ()+swap (Pos x) (Pos y) = getResponse_ ("swap "   ++ show x ++ " " ++ show y)+swap (ID x)  (ID y)  = getResponse_ ("swapid " ++ show x ++ " " ++ show y)+swap _ _ = fail "'swap' cannot mix position and ID arguments"++-- | Shuffle the playlist.+shuffle :: MPD ()+shuffle = getResponse_ "shuffle"++-- | Retrieve metadata for songs in the current playlist.+playlistinfo :: Maybe PLIndex   -- ^ Optional playlist index.+             -> MPD [Song]+playlistinfo x = liftM takeSongs (getResponse cmd)+    where cmd = case x of+                    Just (Pos x') -> "playlistinfo " ++ show x'+                    Just (ID x')  -> "playlistid " ++ show x'+                    Nothing       -> "playlistinfo"++-- | Retrieve metadata for files in a given playlist.+listplaylistinfo :: String -> MPD [Song]+listplaylistinfo = liftM takeSongs . getResponse .+    ("listplaylistinfo " ++) . show++-- | Retrieve a list of files in a given playlist.+listplaylist :: String -> MPD [String]+listplaylist = liftM takeValues . getResponse . ("listplaylist " ++) . show++-- | Retrieve file paths and positions of songs in the current playlist.+-- Note that this command is only included for completeness sake; it's+-- deprecated and likely to disappear at any time.+playlist :: MPD [(PLIndex, String)]+playlist = liftM (map f) (getResponse "playlist")+    where f s = let (pos, name) = break (== ':') s+                in (Pos $ read pos, drop 1 name)++-- | Retrieve a list of changed songs currently in the playlist since+-- a given playlist version.+plchanges :: Integer -> MPD [Song]+plchanges = liftM takeSongs . getResponse . ("plchanges " ++) . show++-- | Like 'plchanges' but only returns positions and ids.+plchangesposid :: Integer -> MPD [(PLIndex, PLIndex)]+plchangesposid plver =+    liftM (map takePosid . splitGroups . kvise) (getResponse cmd)+    where cmd          = "plchangesposid " ++ show plver+          takePosid xs = (Pos $ takeNum "cpos" xs, ID $ takeNum "Id" xs)++-- | Search for songs in the current playlist with strict matching.+playlistfind :: Query -> MPD [Song]+playlistfind = liftM takeSongs . getResponse . ("playlistfind " ++) . show++-- | Search case-insensitively with partial matches for songs in the+-- current playlist.+playlistsearch :: Query -> MPD [Song]+playlistsearch = liftM takeSongs . getResponse . ("playlistsearch " ++) . show++-- | Get the currently playing song.+currentSong :: MPD (Maybe Song)+currentSong = do+    currStatus <- status+    if stState currStatus == Stopped+        then return Nothing+        else do ls <- liftM kvise (getResponse "currentsong")+                return $ if null ls then Nothing+                                    else Just (takeSongInfo ls)++--+-- Playback commands+--++-- | Set crossfading between songs.+crossfade :: Seconds -> MPD ()+crossfade = getResponse_ . ("crossfade " ++) . show++-- | Begin\/continue playing.+play :: Maybe PLIndex -> MPD ()+play Nothing        = getResponse_ "play"+play (Just (Pos x)) = getResponse_ ("play " ++ show x)+play (Just (ID x))  = getResponse_ ("playid " ++ show x)++-- | Pause playing.+pause :: Bool -> MPD ()+pause = getResponse_ . ("pause " ++) . showBool++-- | Stop playing.+stop :: MPD ()+stop = getResponse_ "stop"++-- | Play the next song.+next :: MPD ()+next = getResponse_ "next"++-- | Play the previous song.+previous :: MPD ()+previous = getResponse_ "previous"++-- | Seek to some point in a song.+-- Seeks in current song if no position is given.+seek :: Maybe PLIndex -> Seconds -> MPD ()+seek (Just (Pos x)) time =+    getResponse_ ("seek " ++ show x ++ " " ++ show time)+seek (Just (ID x)) time =+    getResponse_ ("seekid " ++ show x ++ " " ++ show time)+seek Nothing time = do+    st <- status+    unless (stState st == Stopped) (seek (stSongID st) time)++-- | Set random playing.+random :: Bool -> MPD ()+random = getResponse_ . ("random " ++) . showBool++-- | Set repeating.+repeat :: Bool -> MPD ()+repeat = getResponse_ . ("repeat " ++) . showBool++-- | Set the volume.+setVolume :: Int -> MPD ()+setVolume = getResponse_ . ("setvol " ++) . show++-- | Increase or decrease volume by a given percent, e.g.+-- 'volume 10' will increase the volume by 10 percent, while+-- 'volume (-10)' will decrease it by the same amount.+-- Note that this command is only included for completeness sake ; it's+-- deprecated and may disappear at any time.+volume :: Int -> MPD ()+volume = getResponse_ . ("volume " ++) . show++--+-- Miscellaneous commands+--++-- | Clear the current error message in status.+clearerror :: MPD ()+clearerror = getResponse_ "clearerror"++-- | Retrieve a list of available commands.+commands :: MPD [String]+commands = liftM takeValues (getResponse "commands")++-- | Retrieve a list of unavailable commands.+notcommands :: MPD [String]+notcommands = liftM takeValues (getResponse "notcommands")++-- | Retrieve a list of available song metadata.+tagtypes :: MPD [String]+tagtypes = liftM takeValues (getResponse "tagtypes")++-- | Retrieve a list of supported urlhandlers.+urlhandlers :: MPD [String]+urlhandlers = liftM takeValues (getResponse "urlhandlers")++-- XXX should the password be quoted?+-- | Send password to server to authenticate session.+-- Password is sent as plain text.+password :: String -> MPD ()+password = getResponse_ . ("password " ++)++-- | Check that the server is still responding.+ping :: MPD ()+ping = getResponse_ "ping"++-- | Get server statistics.+stats :: MPD Stats+stats = liftM (parseStats . kvise) (getResponse "stats")+    where parseStats xs =+                Stats { stsArtists = takeNum "artists" xs,+                        stsAlbums = takeNum "albums" xs,+                        stsSongs = takeNum "songs" xs,+                        stsUptime = takeNum "uptime" xs,+                        stsPlaytime = takeNum "playtime" xs,+                        stsDbPlaytime = takeNum "db_playtime" xs,+                        stsDbUpdate = takeNum "db_update" xs }++-- | Get the server's status.+status :: MPD Status+status = liftM (parseStatus . kvise) (getResponse "status")+    where parseStatus xs =+              Status { stState = maybe Stopped parseState $ lookup "state" xs,+                     stVolume = takeNum "volume" xs,+                     stRepeat = takeBool "repeat" xs,+                     stRandom = takeBool "random" xs,+                     stPlaylistVersion = takeNum "playlist" xs,+                     stPlaylistLength = takeNum "playlistlength" xs,+                     stXFadeWidth = takeNum "xfade" xs,+                     stSongPos = takeIndex Pos "song" xs,+                     stSongID = takeIndex ID "songid" xs,+                     stTime = maybe (0,0) parseTime $ lookup "time" xs,+                     stBitrate = takeNum "bitrate" xs,+                     stAudio = maybe (0,0,0) parseAudio $ lookup "audio" xs,+                     stUpdatingDb = takeNum "updating_db" xs,+                     stError = takeString "error" xs+                   }+          parseState x = case x of "play"  -> Playing+                                   "pause" -> Paused+                                   _       -> Stopped+          parseTime  x = let (y,_:z) = break (== ':') x in (read y, read z)+          parseAudio x =+              let (u,_:u') = break (== ':') x; (v,_:w) = break (== ':') u' in+                  (read u, read v, read w)++--+-- Extensions\/shortcuts.+--++-- | Like 'update', but returns the update job id.+updateid :: [String] -> MPD Integer+updateid paths = liftM (read . head . takeValues) cmd+  where cmd = case paths of+                []  -> getResponse "update"+                [x] -> getResponse ("update " ++ x)+                xs  -> getResponses (map ("update " ++) xs)++-- | Toggles play\/pause. Plays if stopped.+toggle :: MPD ()+toggle = do+    st <- status+    case stState st of+         Playing -> pause True+         _       -> play Nothing++-- | Add a list of songs\/folders to a playlist.+-- Should be more efficient than running 'add' many times.+addMany :: Maybe String -> [String] -> MPD ()+addMany _ [] = return ()+addMany plname [x] = add_ plname x+addMany plname xs = getResponses (map (cmd ++) xs) >> return ()+    where cmd = maybe ("add ") (\pl -> "playlistadd " ++ show pl ++ " ") plname++-- | Delete a list of songs from a playlist.+-- If there is a duplicate then no further songs will be deleted, so+-- take care to avoid them (see 'prune' for this).+deleteMany :: Maybe String -> [PLIndex] -> MPD ()+deleteMany _ [] = return ()+deleteMany plname [x] = delete plname x+deleteMany (Just plname) xs = getResponses (map cmd xs) >> return ()+    where cmd (Pos x) = "playlistdelete " ++ show plname ++ " " ++ show x+          cmd _       = ""+deleteMany Nothing xs = getResponses (map cmd xs) >> return ()+    where cmd (Pos x) = "delete " ++ show x+          cmd (ID x)  = "deleteid " ++ show x++-- | Crop playlist.+-- The bounds are inclusive.+-- If 'Nothing' or 'ID' is passed the cropping will leave your playlist alone+-- on that side.+crop :: Maybe PLIndex -> Maybe PLIndex -> MPD ()+crop x y = do+    pl <- playlistinfo Nothing+    let x' = case x of Just (Pos p) -> fromInteger p+                       Just (ID i)  -> maybe 0 id (findByID i pl)+                       Nothing      -> 0+        -- ensure that no songs are deleted twice with 'max'.+        ys = case y of Just (Pos p) -> drop (max (fromInteger p) x') pl+                       Just (ID i)  -> maybe [] (flip drop pl . max x' . (+1))+                                      (findByID i pl)+                       Nothing      -> []+    deleteMany Nothing . mapMaybe sgIndex $ take x' pl ++ ys+    where findByID i = findIndex ((==) i . (\(ID j) -> j) . fromJust . sgIndex)++-- | Remove duplicate playlist entries.+prune :: MPD ()+prune = findDuplicates >>= deleteMany Nothing++-- Find duplicate playlist entries.+findDuplicates :: MPD [PLIndex]+findDuplicates =+    liftM (map ((\(ID x) -> ID x) . fromJust . sgIndex) . flip dups ([],[])) $+        playlistinfo Nothing+    where dups [] (_, dup) = dup+          dups (x:xs) (ys, dup)+            | x `elem` xs && x `notElem` ys = dups xs (ys, x:dup)+            | otherwise                     = dups xs (x:ys, dup)++-- | List directories non-recursively.+lsdirs :: Maybe String -- ^ optional path.+       -> MPD [String]+lsdirs path = liftM ((\(x,_,_) -> x) . takeEntries)+                    (getResponse ("lsinfo " ++ maybe "" show path))++-- | List files non-recursively.+lsfiles :: Maybe String -- ^ optional path.+        -> MPD [String]+lsfiles path = liftM (map sgFilePath . (\(_,_,x) -> x) . takeEntries)+                     (getResponse ("lsinfo " ++ maybe "" show path))++-- | List all playlists.+lsplaylists :: MPD [String]+lsplaylists = liftM ((\(_,x,_) -> x) . takeEntries) (getResponse "lsinfo")++-- | Search the database for songs relating to an artist.+findArtist :: Artist -> MPD [Song]+findArtist = find . Query Artist++-- | Search the database for songs relating to an album.+findAlbum :: Album -> MPD [Song]+findAlbum = find . Query Album++-- | Search the database for songs relating to a song title.+findTitle :: Title -> MPD [Song]+findTitle = find . Query Title++-- | List the artists in the database.+listArtists :: MPD [Artist]+listArtists = liftM takeValues (getResponse "list artist")++-- | List the albums in the database, optionally matching a given+-- artist.+listAlbums :: Maybe Artist -> MPD [Album]+listAlbums artist = liftM takeValues (getResponse ("list album" +++    maybe "" ((" artist " ++) . show) artist))++-- | List the songs in an album of some artist.+listAlbum :: Artist -> Album -> MPD [Song]+listAlbum artist album = find (MultiQuery [Query Artist artist+                                          ,Query Album album])++-- | Search the database for songs relating to an artist using 'search'.+searchArtist :: Artist -> MPD [Song]+searchArtist = search . Query Artist++-- | Search the database for songs relating to an album using 'search'.+searchAlbum :: Album -> MPD [Song]+searchAlbum = search . Query Album++-- | Search the database for songs relating to a song title.+searchTitle :: Title -> MPD [Song]+searchTitle = search . Query Title++-- | Retrieve the current playlist.+-- Equivalent to 'playlistinfo Nothing'.+getPlaylist :: MPD [Song]+getPlaylist = playlistinfo Nothing++--+-- Miscellaneous functions.+--++-- Run getResponse but discard the response.+getResponse_ :: String -> MPD ()+getResponse_ x = getResponse x >> return ()++-- Get the lines of the daemon's response to a list of commands.+getResponses :: [String] -> MPD [String]+getResponses cmds = getResponse .+    unlines $ "command_list_begin" : cmds ++ ["command_list_end"]++-- Break up a list of strings into an assoc. list, separating at+-- the first ':'.+kvise :: [String] -> [(String, String)]+kvise = map f+    where f x = let (k,v) = break (== ':') x in+                (k,dropWhile (== ' ') $ drop 1 v)++-- Takes an assoc. list with recurring keys, and groups each cycle of+-- keys with their values together. The first key of each cycle needs+-- to be present in every cycle for it to work, but the rest don't+-- affect anything.+--+-- > splitGroups [(1,'a'),(2,'b'),(1,'c'),(2,'d')] ==+-- >     [[(1,'a'),(2,'b')],[(1,'c'),(2,'d')]]+splitGroups :: Eq a => [(a, b)] -> [[(a, b)]]+splitGroups [] = []+splitGroups (x:xs) = ((x:us):splitGroups vs)+    where (us,vs) = break (\y -> fst x == fst y) xs++-- Run 'kvise' and return only the values.+takeValues :: [String] -> [String]+takeValues = snd . unzip . kvise++-- Separate the result of an lsinfo\/listallinfo call into directories,+-- playlists, and songs.+takeEntries :: [String] -> ([String], [String], [Song])+takeEntries s =+    (dirs, playlists, map takeSongInfo . splitGroups $ reverse filedata)+    where (dirs, playlists, filedata) = foldl split ([], [], []) $ kvise s+          split (ds, pls, ss) x@(k, v) | k == "directory" = (v:ds, pls, ss)+                                       | k == "playlist"  = (ds, v:pls, ss)+                                       | otherwise        = (ds, pls, x:ss)++-- Build a list of song instances from a response.+takeSongs :: [String] -> [Song]+takeSongs = map takeSongInfo . splitGroups . kvise++-- Builds a song instance from an assoc. list.+takeSongInfo :: [(String,String)] -> Song+takeSongInfo xs =+    Song {+          sgArtist    = takeString "Artist" xs,+          sgAlbum     = takeString "Album" xs,+          sgTitle     = takeString "Title" xs,+          sgGenre     = takeString "Genre" xs,+          sgName      = takeString "Name" xs,+          sgComposer  = takeString "Composer" xs,+          sgPerformer = takeString "Performer" xs,+          sgDate      = takeNum "Date" xs,+          sgTrack     = maybe (0, 0) parseTrack $ lookup "Track" xs,+          sgDisc      = maybe (0, 0) parseTrack $ lookup "Disc" xs,+          sgFilePath  = takeString "file" xs,+          sgLength    = takeNum "Time" xs,+          sgIndex     = takeIndex ID "Id" xs+         }+    where parseTrack x = let (trck, tot) = break (== '/') x+                         in (read trck, parseNum (drop 1 tot))++-- Helpers for retrieving values from an assoc. list.+takeString :: String -> [(String, String)] -> String+takeString v = fromMaybe "" . lookup v++takeIndex :: (Integer -> PLIndex) -> String -> [(String, String)]+          -> Maybe PLIndex+takeIndex c v = maybe Nothing (Just . c . parseNum) . lookup v++takeNum :: (Read a, Num a) => String -> [(String, String)] -> a+takeNum v = maybe 0 parseNum . lookup v++takeBool :: String -> [(String, String)] -> Bool+takeBool v = maybe False parseBool . lookup v++-- Parse a numeric value, returning 0 on failure.+parseNum :: (Read a, Num a) => String -> a+parseNum = fromMaybe 0 . maybeReads+    where maybeReads s = do ; [(x, "")] <- return (reads s) ; return x++-- Inverts 'parseBool'.+showBool :: Bool -> String+showBool x = if x then "1" else "0"++-- Parse a boolean response value.+parseBool :: String -> Bool+parseBool = (== "1") . take 1
+ Network/MPD/Prim.hs view
@@ -0,0 +1,269 @@+{-+    libmpd for Haskell, an MPD client library.+    Copyright (C) 2005-2007  Ben Sinclair <bsinclai@turing.une.edu.au>++    This library is free software; you can redistribute it and/or+    modify it under the terms of the GNU Lesser General Public+    License as published by the Free Software Foundation; either+    version 2.1 of the License, or (at your option) any later version.++    This library 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+    Lesser General Public License for more details.++    You should have received a copy of the GNU Lesser General Public+    License along with this library; if not, write to the Free Software+    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA+-}++-- | Module    : Network.MPD.Prim+-- Copyright   : (c) Ben Sinclair 2005-2007+-- License     : LGPL+-- Maintainer  : bsinclai@turing.une.edu.au+-- Stability   : alpha+-- Portability : Haskell 98+--+-- Core functionality.++module Network.MPD.Prim (+    -- * Data types+    MPD, MPDError(..), ACKType(..), Response,++    -- * Running an action+    withMPDEx,++    -- * Errors+    throwMPD, catchMPD,++    -- * Interacting+    getResponse, close, reconnect, kill,+    ) where++import Control.Monad (liftM, unless)+import Control.Exception (finally)+import Control.Monad.Trans+import Prelude hiding (repeat)+import Data.IORef (IORef, newIORef, readIORef, writeIORef)+import Data.List (isPrefixOf)+import Data.Maybe+import Network+import System.IO+import System.IO.Error (isEOFError)++--+-- Data types.+--++-- | A connection to an MPD server.+-- don't export the field names.+data Connection = Conn { connHostName :: String+                       , connPortNum  :: Integer+                       , connHandle   :: IORef (Maybe Handle)+                       , connGetPass  :: IO (Maybe String)+                       }++-- | The MPDError type is used to signal errors, both from the MPD and+-- otherwise.+data MPDError = NoMPD              -- ^ MPD not responding+              | TimedOut           -- ^ The connection timed out+              | Custom String      -- ^ Used for misc. errors+              | ACK ACKType String -- ^ ACK type and a message from the+                                   --   server.++instance Show MPDError where+    show NoMPD      = "Could not connect to MPD"+    show TimedOut   = "MPD connection timed out"+    show (Custom s) = s+    show (ACK _ s)  = s++-- | Represents various MPD errors (aka. ACKs).+data ACKType = InvalidArgument  -- ^ Invalid argument passed (ACK 2)+             | InvalidPassword  -- ^ Invalid password supplied (ACK 3)+             | Auth             -- ^ Authentication required (ACK 4)+             | UnknownCommand   -- ^ Unknown command (ACK 5)+             | FileNotFound     -- ^ File or directory not found ACK 50)+             | PlaylistMax      -- ^ Playlist at maximum size (ACK 51)+             | System           -- ^ A system error (ACK 52)+             | PlaylistLoad     -- ^ Playlist loading failed (ACK 53)+             | Busy             -- ^ Update already running (ACK 54)+             | NotPlaying       -- ^ An operation requiring playback+                                --   got interrupted (ACK 55)+             | FileExists       -- ^ File already exists (ACK 56)+             | UnknownACK       -- ^ An unknown ACK (aka. bug)++-- | A response is either an ACK or some result.+type Response a = Either MPDError a++-- Export the type name but not the constructor or the field.+--+-- This is basically a state and an error monad combined. It's just+-- nice if we can have a few custom functions that fiddle with the+-- internals.+newtype MPD a = MPD { runMPD :: Connection -> IO (Response a) }++instance Functor MPD where+    fmap f m = MPD $ \conn -> either Left (Right . f) `liftM` runMPD m conn++instance Monad MPD where+    return a = MPD $ \_ -> return (Right a)+    m >>= f  = MPD $ \conn -> runMPD m conn >>=+                              either (return . Left) (flip runMPD conn . f)+    fail err = MPD $ \_ -> return . Left $ Custom err++instance MonadIO MPD where+    liftIO m = MPD $ \_ -> liftM Right m++-- | Throw an exception.+throwMPD :: MPDError -> MPD ()+throwMPD e = MPD $ \_ -> return (Left e)++-- | Catch an exception from an action.+catchMPD :: MPD a -> (MPDError -> MPD a) -> MPD a+catchMPD m h = MPD $ \conn ->+    runMPD m conn >>= either (flip runMPD conn . h) (return . Right)++--+-- Basic connection functions+--++-- | Run an MPD action against a server.+withMPDEx :: String            -- ^ Host name.+          -> Integer           -- ^ Port number.+          -> IO (Maybe String) -- ^ An action that supplies passwords.+          -> MPD a             -- ^ The action to run.+          -> IO (Response a)+withMPDEx host port getpw m = do+    hRef <- newIORef Nothing+    connect host port hRef+    readIORef hRef >>= maybe (return $ Left NoMPD)+        (\_ -> finally (runMPD m $ Conn host port hRef getpw) (closeIO hRef))++-- Connect to an MPD server.+connect :: String -> Integer -- host and port+        -> IORef (Maybe Handle) -> IO ()+connect host port hRef =+    withSocketsDo $ do+        closeIO hRef+        handle <- safeConnectTo host port+        writeIORef hRef handle+        maybe (return ()) (\h -> checkConn h >>= flip unless (closeIO hRef))+              handle++safeConnectTo :: String -> Integer -> IO (Maybe Handle)+safeConnectTo host port =+    catch (liftM Just $ connectTo host (PortNumber $ fromInteger port))+          (const $ return Nothing)++-- Check that an MPD daemon is at the other end of a connection.+checkConn :: Handle -> IO Bool+checkConn h = isPrefixOf "OK MPD" `liftM` hGetLine h++-- Close a connection.+closeIO :: IORef (Maybe Handle) -> IO ()+closeIO hRef = do+    readIORef hRef >>= maybe (return ())+                             (\h -> hPutStrLn h "close" >> hClose h)+    writeIORef hRef Nothing++-- | Refresh a connection.+reconnect :: MPD ()+reconnect = MPD $ \(Conn host port hRef _) -> do+    connect host port hRef+    liftM (maybe (Left NoMPD) (const $ Right ())) (readIORef hRef)++-- | Kill the server. Obviously, the connection is then invalid.+kill :: MPD ()+kill = getResponse "kill" `catchMPD` cleanup >> return ()+    where cleanup TimedOut = MPD $ \conn -> do+              readIORef (connHandle conn) >>= maybe (return ()) hClose+              writeIORef (connHandle conn) Nothing+              return (Right [])+          cleanup x = throwMPD x >> return []++-- | Close an MPD connection.+close :: MPD ()+close = MPD $ \conn -> closeIO (connHandle conn) >> return (Right ())++-- | Send a command to the MPD and return the result.+getResponse :: String -> MPD [String]+getResponse cmd = MPD $ \conn -> respRead (sendCmd conn) reader (givePW conn)+    where sendCmd conn =+              readIORef (connHandle conn) >>=+              maybe (return $ Left NoMPD)+                    (\h -> hPutStrLn h cmd >> hFlush h >> return (Right h))+          reader h = getLineTO h >>= return . (either Left parseResponse)+          givePW conn cont (ACK Auth _) = tryPassword conn cont+          givePW _ _ ack = return (Left ack)++-- Get a line of text, handling a timed-out connection.+getLineTO :: Handle -> IO (Response String)+getLineTO h = catch (liftM Right $ hGetLine h)+                    (\err -> if isEOFError err then return $ Left TimedOut+                                               else ioError err)++-- Send a password to MPD and run an action on success.+tryPassword :: Connection -> IO (Response a) -> IO (Response a)+tryPassword conn cont =+    readIORef (connHandle conn) >>= maybe (return $ Left NoMPD) get+    where+        get h = connGetPass conn >>=+                maybe (return . Left $ ACK Auth "Password required") (send h)+        send h pw = do hPutStrLn h ("password " ++ pw) >> hFlush h+                       result <- hGetLine h+                       case result of "OK" -> cont+                                      _    -> tryPassword conn cont++-- XXX suggestions for names welcome.+--+-- Run a setup action before a recurrent reader. If the reader returns+-- Nothing it has finished reading. If an error is returned a handler+-- is called with an action that, when invoked, will run the setup+-- action again and continue.+respRead :: IO (Either e a)                               -- setup+         -> (a -> IO (Either e (Maybe b)))                -- reader+         -> (IO (Either e [b]) -> e -> IO (Either e [b])) -- handler+         -> IO (Either e [b])+respRead sup rdr onErr = start []+    where start acc = sup >>= either (return . Left) (\x -> readAll x acc)+          readAll x acc =+              rdr x >>= either (onErr (start acc))+                               (maybe result (\y -> readAll x (y:acc)))+              where result = return $ Right (reverse acc)++-- Consume response and return a Response.+parseResponse :: String -> Response (Maybe String)+parseResponse s | isPrefixOf "ACK" s = Left  $ parseAck s+                | isPrefixOf "OK" s  = Right Nothing+                | otherwise          = Right $ Just s++parseAck :: String -> MPDError+parseAck s = ACK ack msg+    where+        ack = case code of+                "2"  -> InvalidArgument+                "3"  -> InvalidPassword+                "4"  -> Auth+                "5"  -> UnknownCommand+                "50" -> FileNotFound+                "51" -> PlaylistMax+                "52" -> System+                "53" -> PlaylistLoad+                "54" -> Busy+                "55" -> NotPlaying+                "56" -> FileExists+                _    -> UnknownACK+        (code, _, msg) = splitAck s++-- Break an ACK into (error code, current command, message).+-- ACKs are of the form:+-- ACK [error@command_listNum] {current_command} message_text\n+splitAck :: String -> (String, String, String)+splitAck s = (code, cmd, msg)+    where (code, notCode) = between (== '[') (== '@') s+          (cmd, notCmd)   = between (== '{') (== '}') notCode+          msg             = drop 1 . snd $ break (== ' ') notCmd++          -- take whatever is between 'f' and 'g'.+          between f g xs  = let (_, y) = break f xs+                            in break g (drop 1 y)
+ README view
@@ -0,0 +1,43 @@++           libmpd-haskell : An MPD client library for Haskell+         ------------------------------------------------------++Dependencies:+    The Glasgow Haskell Compiler >= 6.4       http://haskell.org/ghc+    Cabal > 1.0                               http://haskell.org/cabal+    network                                   http://hackage.haskell.org/cgi-bin/hackage-scripts/package/network+    mtl                                       http://hackage.haskell.org/cgi-bin/hackage-scripts/package/mtl++Building:+    $ chmod +x configure Setup.lhs+    $ ./Setup.lhs configure --prefix=${HOME}+    $ ./Setup.lhs build+    $ ./Setup.lhs install --user++    This assumes you have Cabal installed. Cabal is installed by+    default with newer GHCs.++Use:+    Import the MPD module and specify the mpd package (-package mpd)+    when compiling, or add it to the `Build-Depends' list in your+    `_.cabal' file.++Limitations:+    Most of the API is complete, but some parts, most notably parsing, are+    not yet as good as they could be.++Platforms:+    libmpd-haskell has been confirmed to work on:+        Linux/x86+    Seems to work on Windows XP as well, but there is no MPD support for+    that platform.++Latest Sources:+    darcs get http://turing.une.edu.au/~bsinclai/code/libmpd-haskell++License:+    LGPL++Authors:+    Ben Sinclair <bsinclai@turing.une.edu.au>+    Joachim Fasting <joachim.fasting@gmail.com>
+ Setup.lhs view
@@ -0,0 +1,5 @@+#!/usr/bin/env runhaskell+> module Main where+> import Distribution.Simple+> main :: IO ()+> main = defaultMain
+ TODO view
@@ -0,0 +1,4 @@+TODO:+    - improve parsing performance+    - find a way to retrieve the name of the currently loaded+    playlist (if any). should return "current" by default.
+ libmpd.cabal view
@@ -0,0 +1,19 @@+Name:               libmpd+Version:            0.1.2+License:            LGPL+License-file:       LICENSE+Copyright:          Ben Sinclair 2005-2007+Author:             Ben Sinclair+Maintainer:         bsinclai@turing.une.edu.au+Stability:          alpha+Homepage:           http://turing.une.edu.au/~bsinclai/code/libmpd-haskell.html+Synopsis:           An MPD client library.+Description:        A client library for MPD, the Music Player Daemon.+Category:           Network, Sound+Tested-With:        GHC == 6.5, GHC == 6.6.1, Hugs == 2006.9+Build-Depends:      base, network, mtl+Extra-Source-Files: TODO README ChangeLog+Exposed-Modules:    Network.MPD+Other-Modules:      Network.MPD.Prim, Network.MPD.Commands+ghc-options:        -Wall -O2+ghc-prof-options:   -auto-all -prof