/* Title: Pure/System/session.scala
Author: Makarius
Options: :folding=explicit:collapseFolds=1:
Main Isabelle/Scala session, potentially with running prover process.
*/
package isabelle
import java.lang.System
import scala.actors.TIMEOUT
import scala.actors.Actor
import scala.actors.Actor._
object Session
{
/* file store */
abstract class File_Store
{
def read(path: Path): String
}
/* events */
//{{{
case object Global_Settings
case object Perspective
case object Assignment
case class Commands_Changed(set: Set[Command])
sealed abstract class Phase
case object Inactive extends Phase
case object Startup extends Phase // transient
case object Failed extends Phase
case object Ready extends Phase
case object Shutdown extends Phase // transient
//}}}
}
class Session(val file_store: Session.File_Store)
{
/* real time parameters */ // FIXME properties or settings (!?)
val input_delay = Time.seconds(0.3) // user input (e.g. text edits, cursor movement)
val output_delay = Time.seconds(0.1) // prover output (markup, common messages)
val update_delay = Time.seconds(0.5) // GUI layout updates
/* pervasive event buses */
val global_settings = new Event_Bus[Session.Global_Settings.type]
val perspective = new Event_Bus[Session.Perspective.type]
val assignments = new Event_Bus[Session.Assignment.type]
val commands_changed = new Event_Bus[Session.Commands_Changed]
val phase_changed = new Event_Bus[Session.Phase]
val raw_messages = new Event_Bus[Isabelle_Process.Message]
/** buffered command changes (delay_first discipline) **/
//{{{
private case object Stop
private val (_, command_change_buffer) =
Simple_Thread.actor("command_change_buffer", daemon = true)
{
var changed: Set[Command] = Set()
var flush_time: Option[Long] = None
def flush_timeout: Long =
flush_time match {
case None => 5000L
case Some(time) => (time - System.currentTimeMillis()) max 0
}
def flush()
{
if (!changed.isEmpty) commands_changed.event(Session.Commands_Changed(changed))
changed = Set()
flush_time = None
}
def invoke()
{
val now = System.currentTimeMillis()
flush_time match {
case None => flush_time = Some(now + output_delay.ms)
case Some(time) => if (now >= time) flush()
}
}
var finished = false
while (!finished) {
receiveWithin(flush_timeout) {
case command: Command => changed += command; invoke()
case TIMEOUT => flush()
case Stop => finished = true; reply(())
case bad => System.err.println("command_change_buffer: ignoring bad message " + bad)
}
}
}
//}}}
/** main protocol actor **/
/* global state */
@volatile var verbose: Boolean = false
@volatile private var loaded_theories: Set[String] = Set()
@volatile private var syntax = new Outer_Syntax
def current_syntax(): Outer_Syntax = syntax
@volatile private var reverse_syslog = List[XML.Elem]()
def syslog(): String = reverse_syslog.reverse.map(msg => XML.content(msg).mkString).mkString("\n")
@volatile private var _phase: Session.Phase = Session.Inactive
private def phase_=(new_phase: Session.Phase)
{
_phase = new_phase
phase_changed.event(new_phase)
}
def phase = _phase
def is_ready: Boolean = phase == Session.Ready
private val global_state = new Volatile(Document.State.init)
def current_state(): Document.State = global_state()
def snapshot(name: String, pending_edits: List[Text.Edit]): Document.Snapshot =
global_state().snapshot(name, pending_edits)
/* theory files */
val thy_load = new Thy_Load
{
override def is_loaded(name: String): Boolean =
loaded_theories.contains(name)
override def check_thy(dir: Path, name: String): (String, Thy_Header.Header) =
{
val file = Isabelle_System.platform_file(dir + Thy_Header.thy_path(name))
if (!file.exists || !file.isFile) error("No such file: " + quote(file.toString))
val text = Standard_System.read_file(file)
val header = Thy_Header.read(text)
(text, header)
}
}
val thy_info = new Thy_Info(thy_load)
/* actor messages */
private case class Start(timeout: Time, args: List[String])
private case object Interrupt
private case class Init_Node(name: String, header: Document.Node.Header, text: String)
private case class Edit_Node(name: String, header: Document.Node.Header, edits: List[Text.Edit])
private case class Change_Node(
name: String,
doc_edits: List[Document.Edit_Command],
previous: Document.Version,
version: Document.Version)
private val (_, session_actor) = Simple_Thread.actor("session_actor", daemon = true)
{
val this_actor = self
var prover: Option[Isabelle_Process with Isar_Document] = None
/* incoming edits */
def handle_edits(name: String,
header: Document.Node.Header, edits: List[Document.Node.Edit[Text.Edit]])
//{{{
{
val syntax = current_syntax()
val previous = global_state().history.tip.version
val doc_edits =
(name, Document.Node.Update_Header[Text.Edit](header)) :: edits.map(edit => (name, edit))
val result = Future.fork { Thy_Syntax.text_edits(syntax, previous.join, doc_edits) }
val change =
global_state.change_yield(_.extend_history(previous, doc_edits, result.map(_._2)))
result.map {
case (doc_edits, _) =>
assignments.await { global_state().is_assigned(previous.get_finished) }
this_actor ! Change_Node(name, doc_edits, previous.join, change.version.join)
}
}
//}}}
/* resulting changes */
def handle_change(change: Change_Node)
//{{{
{
val previous = change.previous
val version = change.version
val name = change.name
val doc_edits = change.doc_edits
var former_assignment = global_state().the_assignment(previous).get_finished
for {
(name, Document.Node.Edits(cmd_edits)) <- doc_edits // FIXME proper coverage!?
(prev, None) <- cmd_edits
removed <- previous.nodes(name).commands.get_after(prev)
} former_assignment -= removed
def id_command(command: Command): Document.Command_ID =
{
if (global_state().lookup_command(command.id).isEmpty) {
global_state.change(_.define_command(command))
prover.get.define_command(command.id, Symbol.encode(command.source))
}
command.id
}
val id_edits =
doc_edits map {
case (name, edit) =>
(name, edit.map({ case (c1, c2) => (c1.map(id_command), c2.map(id_command)) }))
}
global_state.change(_.define_version(version, former_assignment))
prover.get.edit_version(previous.id, version.id, id_edits)
}
//}}}
/* prover results */
def handle_result(result: Isabelle_Process.Result)
//{{{
{
def bad_result(result: Isabelle_Process.Result)
{
if (verbose)
System.err.println("Ignoring prover result: " + result.message.toString)
}
result.properties match {
case Position.Id(state_id) if !result.is_raw =>
try {
val st = global_state.change_yield(_.accumulate(state_id, result.message))
command_change_buffer ! st.command
}
catch {
case _: Document.State.Fail => bad_result(result)
}
case Markup.Invoke_Scala(name, id) if result.is_raw =>
Future.fork {
val arg = XML.content(result.body).mkString
val (tag, res) = Invoke_Scala.method(name, arg)
prover.get.invoke_scala(id, tag, res)
}
case _ =>
if (result.is_syslog) {
reverse_syslog ::= result.message
if (result.is_ready) {
// FIXME move to ML side (!?)
syntax += ("hence", Keyword.PRF_ASM_GOAL, "then have")
syntax += ("thus", Keyword.PRF_ASM_GOAL, "then show")
phase = Session.Ready
}
else if (result.is_exit && phase == Session.Startup) phase = Session.Failed
else if (result.is_exit) phase = Session.Inactive
}
else if (result.is_stdout) { }
else if (result.is_status) {
result.body match {
case List(Isar_Document.Assign(id, edits)) =>
try {
val cmds: List[Command] = global_state.change_yield(_.assign(id, edits))
for (cmd <- cmds) command_change_buffer ! cmd
assignments.event(Session.Assignment)
}
catch { case _: Document.State.Fail => bad_result(result) }
case List(Keyword.Command_Decl(name, kind)) => syntax += (name, kind)
case List(Keyword.Keyword_Decl(name)) => syntax += name
case List(Thy_Info.Loaded_Theory(name)) => loaded_theories += name
case _ => bad_result(result)
}
}
else bad_result(result)
}
}
//}}}
/* main loop */
//{{{
var finished = false
while (!finished) {
receive {
case Start(timeout, args) if prover.isEmpty =>
if (phase == Session.Inactive || phase == Session.Failed) {
phase = Session.Startup
prover = Some(new Isabelle_Process(timeout, this_actor, args:_*) with Isar_Document)
}
case Stop =>
if (phase == Session.Ready) {
global_state.change(_ => Document.State.init) // FIXME event bus!?
phase = Session.Shutdown
prover.get.terminate
prover = None
phase = Session.Inactive
}
finished = true
reply(())
case Interrupt if prover.isDefined =>
prover.get.interrupt
case Init_Node(name, header, text) if prover.isDefined =>
// FIXME compare with existing node
handle_edits(name, header,
List(Document.Node.Remove(), Document.Node.Edits(List(Text.Edit.insert(0, text)))))
reply(())
case Edit_Node(name, header, text_edits) if prover.isDefined =>
handle_edits(name, header, List(Document.Node.Edits(text_edits)))
reply(())
case change: Change_Node if prover.isDefined =>
handle_change(change)
case input: Isabelle_Process.Input =>
raw_messages.event(input)
case result: Isabelle_Process.Result =>
handle_result(result)
raw_messages.event(result)
case bad => System.err.println("session_actor: ignoring bad message " + bad)
}
}
//}}}
}
/* actions */
def start(timeout: Time, args: List[String]) { session_actor ! Start(timeout, args) }
def stop() { command_change_buffer !? Stop; session_actor !? Stop }
def interrupt() { session_actor ! Interrupt }
def init_node(name: String, header: Document.Node.Header, text: String)
{ session_actor !? Init_Node(name, header, text) }
def edit_node(name: String, header: Document.Node.Header, edits: List[Text.Edit])
{ session_actor !? Edit_Node(name, header, edits) }
}