/*
* Isabelle session, potentially with running prover
*
* @author Makarius
*/
package isabelle.proofdocument
import scala.actors.TIMEOUT
import scala.actors.Actor._
object Session
{
/* events */
case object Global_Settings
/* managed entities */
type Entity_ID = String
trait Entity
{
val id: Entity_ID
def consume(session: Session, message: XML.Tree): Unit
}
}
class Session(system: Isabelle_System)
{
/* pervasive event buses */
val global_settings = new Event_Bus[Session.Global_Settings.type]
val raw_results = new Event_Bus[Isabelle_Process.Result]
val results = new Event_Bus[Command]
val command_change = new Event_Bus[Command]
val document_change = new Event_Bus[Document]
/* unique ids */
private var id_count: BigInt = 0
def create_id(): Session.Entity_ID = synchronized { id_count += 1; "j" + id_count }
/* document state information -- owned by session_actor */
@volatile private var syntax = new Outer_Syntax(system.symbols)
def current_syntax: Outer_Syntax = syntax
@volatile private var entities = Map[Session.Entity_ID, Session.Entity]()
def lookup_entity(id: Session.Entity_ID): Option[Session.Entity] = entities.get(id)
// FIXME eliminate
@volatile private var documents = Map[Isar_Document.Document_ID, Document]()
def document(id: Isar_Document.Document_ID): Option[Document] = documents.get(id)
/** main actor **/
private case class Register(entity: Session.Entity)
private case class Start(timeout: Int, args: List[String])
private case object Stop
private case class Begin_Document(path: String)
private val session_actor = actor {
var prover: Isabelle_Process with Isar_Document = null
def register(entity: Session.Entity) { entities += (entity.id -> entity) }
/* document changes */
def handle_change(change: Change)
{
val old = document(change.parent.get.id).get
val (doc, changes) = old.text_changed(this, change)
val id_changes = changes map {
case (c1, c2) =>
(c1.map(_.id).getOrElse(""),
c2 match {
case None => None
case Some(command) => // FIXME clarify -- may reuse existing commands!??
register(command)
prover.define_command(command.id, system.symbols.encode(command.content))
Some(command.id)
})
}
register(doc)
documents += (doc.id -> doc)
prover.edit_document(old.id, doc.id, id_changes)
document_change.event(doc)
}
/* prover results */
def handle_result(result: Isabelle_Process.Result)
{
raw_results.event(result)
val target: Option[Session.Entity] =
Position.get_id(result.props) match {
case None => None
case Some(id) => entities.get(id)
}
if (target.isDefined) target.get.consume(this, result.message)
else if (result.kind == Isabelle_Process.Kind.STATUS) {
// global status message
for (elem <- result.body) {
elem match {
// command and keyword declarations
case XML.Elem(Markup.COMMAND_DECL, (Markup.NAME, name) :: (Markup.KIND, kind) :: _, _) =>
syntax += (name, kind)
case XML.Elem(Markup.KEYWORD_DECL, (Markup.NAME, name) :: _, _) =>
syntax += name
case _ =>
}
}
}
else if (result.kind == Isabelle_Process.Kind.EXIT)
prover = null
}
/* prover startup */
def startup_error(): String =
{
val buf = new StringBuilder
while (
receiveWithin(0) {
case result: Isabelle_Process.Result =>
if (result.is_raw) {
for (text <- XML.content(result.message))
buf.append(text)
}
true
case TIMEOUT => false
}) {}
buf.toString
}
def prover_startup(timeout: Int): Option[String] =
{
receiveWithin(timeout) {
case result: Isabelle_Process.Result
if result.kind == Isabelle_Process.Kind.INIT =>
while (receive {
case result: Isabelle_Process.Result =>
handle_result(result); !result.is_ready
}) {}
None
case result: Isabelle_Process.Result
if result.kind == Isabelle_Process.Kind.EXIT =>
Some(startup_error())
case TIMEOUT => // FIXME clarify
prover.kill; Some(startup_error())
}
}
/* main loop */
val xml_cache = new XML.Cache(131071)
loop {
react {
case Register(entity: Session.Entity) =>
register(entity)
reply(())
case Start(timeout, args) =>
if (prover == null) {
prover = new Isabelle_Process(system, self, args:_*) with Isar_Document
val origin = sender
val opt_err = prover_startup(timeout)
if (opt_err.isDefined) prover = null
origin ! opt_err
}
else reply(None)
case Stop => // FIXME clarify; synchronous
if (prover != null) {
prover.kill
prover = null
}
case Begin_Document(path: String) if prover != null =>
val id = create_id()
val doc = Document.empty(id)
register(doc)
documents += (id -> doc)
prover.begin_document(id, path)
reply(doc)
case change: Change if prover != null =>
handle_change(change)
case result: Isabelle_Process.Result =>
handle_result(result.cache(xml_cache))
case bad if prover != null =>
System.err.println("session_actor: ignoring bad message " + bad)
}
}
}
/* main methods */
def register_entity(entity: Session.Entity) { session_actor !? Register(entity) }
def start(timeout: Int, args: List[String]): Option[String] =
(session_actor !? Start(timeout, args)).asInstanceOf[Option[String]]
def stop() { session_actor ! Stop }
def input(change: Change) { session_actor ! change }
def begin_document(path: String): Document =
(session_actor !? Begin_Document(path)).asInstanceOf[Document]
}