-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | Binding to the OS level Midi services (fork of system-midi).
--   
--   Cross-platform binding to Midi libraries. Supports OS X and Windows
--   (limited testing). The API use the same represeentation as Codec.Midi
--   so system and file I/O have the same interface. This package was based
--   on the system-midi package.
@package hamid
@version 0.10


-- | A lowest common denominator interface to the Win32 and MacOSX Midi
--   bindings. Error handling is via <a>fail</a>-s in the IO monad.
module System.Midi
type MidiTime = Word32
type MidiMessage = Message
type MidiEvent = (MidiTime, Message)
class MidiHasName a
name :: MidiHasName a => a -> IO String

-- | The opaque data type representing a Midi source.
data Source

-- | Enumerates the Midi sources present in the system.
sources :: IO [Source]

-- | The opaque data type representing a Midi destination.
data Destination

-- | Enumerates the Midi destinations present in the system.
destinations :: IO [Destination]

-- | Opens a Midi Source. There are two possibilites to receive Midi
--   messages. The user can either support a callback function, or get the
--   messages from an asynchronous buffer. However, mixing the two
--   approaches is not allowed.
openSource :: Source -> Maybe (MidiTime -> Message -> IO ()) -> IO Stream

-- | Opens a Midi Destination.
openDestination :: Destination -> IO Stream

-- | The opaque data type representing a Midi connection.
data Stream

-- | Closes a Midi Stream.
close :: Stream -> IO ()

-- | Starts a connection. This is required for receiving Midi messages, and
--   also for starting the clock.
start :: Stream -> IO ()

-- | Stops a connection.
stop :: Stream -> IO ()

-- | Sends a short message. The connection must be a <a>Destination</a>.
send :: Stream -> Message -> IO ()

-- | Gets the next event from a buffered connection (see also
--   <a>openSource</a>)
getNextEvent :: Stream -> IO (Maybe MidiEvent)

-- | Gets all the events from the buffer (see also <a>openSource</a>)
getEvents :: Stream -> IO [MidiEvent]

-- | Returns the time elapsed since the last <a>start</a> call, in
--   milisecs.
currentTime :: Stream -> IO MidiTime
instance Eq Source
instance Eq Destination
instance Show Destination
instance Show Source
instance MidiHasName Destination
instance MidiHasName Source