package ch.jodersky.flow
import akka.actor.ExtensionKey
import akka.util.ByteString
/** Defines messages used by flow's serial IO layer. */
object Serial extends ExtensionKey[SerialExt] {
/** Base trait for any flow-related messages. */
sealed trait Message
/** A message extending this trait is to be viewed as a command, an out-bound message issued by the client to flow's API. */
trait Command extends Message
/** A message extending this trait is to be viewed as an event, an in-bound message issued by flow to the client. */
trait Event extends Message
/** A command has failed. */
case class CommandFailed(command: Command, reason: Throwable) extends Event
/**
* Open a new serial port.
*
* Send this command to the serial manager to request the opening of a serial port. The manager will
* attempt to open a serial port with the specified parameters and, if successful, create a `SerialOperator` actor associated to the port.
* The operator actor acts as an intermediate to the underlying native serial port, dealing with threading issues and dispatching messages.
*
* In case the port is successfully opened, the operator will respond with an `Opened` message.
* In case the port cannot be opened, the manager will respond with a `CommandFailed` message.
*
* @param port name of serial port to open
* @param settings settings of serial port to open
* @param bufferSize maximum read and write buffer sizes
*/
case class Open(port: String, settings: SerialSettings, bufferSize: Int = 1024) extends Command
/**
* A port has been successfully opened.
*
* Event sent by a port operator, indicating that a serial port was successfully opened. The sender
* of this message is the operator associated to the given serial port.
*
* @param port name of opened serial port
*/
case class Opened(port: String) extends Event
/**
* Data has been received.
*
* Event sent by an operator, indicating that data was received on the operator's serial port.
*
* @param data data received on the port
*/
case class Received(data: ByteString) extends Event
/**
* Write data to a serial port.
*
* Send this command to an operator to write the given data to its associated serial port.
* An acknowledgment may be set, in which case it is sent back to the sender on a successful write.
* Note that a successful write does not guarantee the actual transmission of data through the serial port,
* it merely guarantees that the data has been stored in the operating system's kernel buffer, ready to
* be transmitted.
*
* @param data data to be written to port
* @param ack acknowledgment sent back to sender once data has been enqueued in kernel for sending (the acknowledgment
* is a function 'number of bytes written => event')
*/
case class Write(data: ByteString, ack: Int => Event = NoAck) extends Command
/**
* Special type of acknowledgment that is not sent back.
*/
case object NoAck extends Function1[Int, Event] {
def apply(length: Int) = sys.error("cannot apply NoAck")
}
/**
* Request closing of port.
*
* Send this command to an operator to close its associated port. The operator will respond
* with a `Closed` message upon closing the serial port.
*/
case object Close extends Command
/**
* A port has been closed.
*
* Event sent from operator, indicating that its port has been closed.
*/
case object Closed extends Event
/**
* Watch a directory for new ports.
*
* Send this command to the manager to get notifications when a new port (i.e. file) is created in
* the given directory.
* In case the given directory cannot be watched, the manager responds with a `CommandFailed` message.
*
* Note: the sender is also notified of currently existing ports.
*
* @param directory the directory to watch
* @param skipInitial don't get notified of already existing ports
*
* @see Unwatch
* @see Connected
*/
case class Watch(directory: String = "/dev", skipInitial: Boolean = false) extends Command
/**
* Stop receiving notifications about a previously watched directory.
*
* @param directory the directory to unwatch
*/
case class Unwatch(directory: String = "/dev") extends Command
/**
* A new port (i.e. file) has been detected.
*
* @param port the absolute file name of the connected port
*/
case class Connected(port: String) extends Event
/**
* Sets native debugging mode. If debugging is enabled, detailed error messages
* are printed (to stderr) from native method calls.
*
* @param value set to enable debugging
*/
def debug(value: Boolean) = UnsafeSerial.debug(value)
}
