Refactorings of the Scion client code.

Now uses the Eclipse job scheduler to run commands.
This is a lot cleaner than using our own command queue;
moreover, it gives us more flexibility such as job priorities and cancellation.

Also, made parts of ...scion.client internal for
a cleaner separation of interface and implementation.

net.sf.eclipsefp.haskell-feature/feature.xml

@@ -24,7 +24,6 @@ available at http://www.eclipse.org/legal/epl-v10.html.
       <import plugin="org.eclipse.ui.cheatsheets" version="3.2.0" match="compatible"/>
       <import plugin="net.sf.eclipsefp.haskell.ui"/>
       <import plugin="net.sf.eclipsefp.haskell.haddock"/>
-      <import plugin="de.leiffrenzel.cohatoe.server.core"/>
       <import plugin="org.eclipse.core.expressions" version="3.2.0" match="compatible"/>
       <import plugin="org.eclipse.core.runtime" version="3.2.0" match="compatible"/>
       <import plugin="org.eclipse.debug.core" version="3.2.0" match="compatible"/>

net.sf.eclipsefp.haskell.core/META-INF/MANIFEST.MF

@@ -7,7 +7,8 @@ Bundle-Vendor: %bundleVendor
 Bundle-Localization: plugin
 Require-Bundle: org.eclipse.core.expressions;bundle-version="[3.2.0,4.0.0)",
  org.eclipse.core.runtime;bundle-version="[3.2.0,4.0.0)",
- org.eclipse.debug.core;bundle-version="[3.2.0,4.0.0)"
+ org.eclipse.debug.core;bundle-version="[3.2.0,4.0.0)",
+ net.sf.eclipsefp.haskell.scion.client;bundle-version="0.13.0"
 Bundle-ActivationPolicy: lazy
 Bundle-ManifestVersion: 2
 Bundle-RequiredExecutionEnvironment: J2SE-1.5

net.sf.eclipsefp.haskell.scion.client/META-INF/MANIFEST.MF

@@ -13,5 +13,4 @@ Require-Bundle: org.eclipse.core.runtime;bundle-version="3.5.0",
  org.eclipse.text
 Bundle-Vendor: Thomas ten Cate <ttencate@gmail.com>
 Export-Package: net.sf.eclipsefp.haskell.scion.client,
- net.sf.eclipsefp.haskell.scion.commands,
  net.sf.eclipsefp.haskell.scion.types

net.sf.eclipsefp.haskell.scion.client/build.properties

@@ -1,9 +1,9 @@
-source.. = src/
+source.. = src/,\
+           lib/
 output.. = bin/
 bin.includes = META-INF/,\
                .,\
                plugin.properties,\
-               about.html,\
-               plugin.xml
+               about.html
 src.includes = src/,\
                lib/

net.sf.eclipsefp.haskell.scion.client/plugin.properties

@@ -5,16 +5,3 @@
 # bundle manifest
 bundleVendor = Thomas ten Cate <ttencate@gmail.com>
 bundleName = Scion Client for EclipseFP
-
-# Preferences
-ScionPP.name = Scion
-ScionServerExecutable.label = &Server executable (%1$s):
-AutodetectButton.label = Try to find the server executable in common directories:
-AutodetectButton.text = &Autodetect
-AutodetectButton.errorTitle = Server executable not found
-AutodetectButton.errorMessage = The Scion server executable, %1$s, could not be found.\n\nMake sure that Scion is installed on your system. If Scion is installed, try specifying the location of %1$s by hand.
-
-# ExecutableFileFieldEditor
-ExecutableFileFieldEditor.errorDoesNotExist = The specified file must exist
-ExecutableFileFieldEditor.errorNotAbsolute = Path must be absolute
-ExecutableFileFieldEditor.errorNotExecutable = The specified file must be executable

net.sf.eclipsefp.haskell.scion.client/src/net/sf/eclipsefp/haskell/scion/client/ScionInstance.java

@@ -0,0 +1,119 @@
+package net.sf.eclipsefp.haskell.scion.client;
+
+import net.sf.eclipsefp.haskell.scion.internal.client.ScionThreadManager;
+import net.sf.eclipsefp.haskell.scion.internal.commands.BackgroundTypecheckFileCommand;
+import net.sf.eclipsefp.haskell.scion.internal.commands.ConnectionInfoCommand;
+import net.sf.eclipsefp.haskell.scion.internal.commands.LoadCommand;
+import net.sf.eclipsefp.haskell.scion.internal.commands.NameDefinitionsCommand;
+import net.sf.eclipsefp.haskell.scion.internal.commands.ThingAtPointCommand;
+import net.sf.eclipsefp.haskell.scion.internal.util.Multiset;
+import net.sf.eclipsefp.haskell.scion.types.Location;
+
+/**
+ * Manages a single instance of the Scion server.
+ * 
+ * This is one level above {@link ScionThreadManager}, in the sense that it is concerned
+ * with the semantics of the commands, instead of the mechanics of sending and receiving.
+ * 
+ * Objects from this class keep track of the state of the Scion server, so that the server
+ * can be put into the same state after a restart (either of the server, or of the entire
+ * workbench). 
+ * 
+ * @author Thomas ten Cate
+ */
+public class ScionInstance {
+
+	private String serverExecutable;
+	private ScionThreadManager threadManager;
+	private Multiset<String> loadedFiles = new Multiset<String>();
+
+	public ScionInstance(String serverExecutable) {
+		this.serverExecutable = serverExecutable;
+		createThreadManager();
+	}
+
+	public String getServerExecutable() {
+		return serverExecutable;
+	}
+
+	public void setServerExecutable(String serverExecutable) {
+		if (!this.serverExecutable.equals(serverExecutable)) {
+			destroyThreadManager();
+			this.serverExecutable = serverExecutable;
+			createThreadManager();
+		}
+	}
+
+	public void stop() {
+		destroyThreadManager();
+	}
+
+	////////////////////////////
+	// Thread manager handling
+
+	private void createThreadManager() {
+		threadManager = new ScionThreadManager(serverExecutable);
+	}
+
+	private void destroyThreadManager() {
+		threadManager.dispose();
+		threadManager = null;
+	}
+
+	////////////////
+	// State stuff
+
+
+	//////////////////////
+	// Specific commands
+
+	private void checkProtocol() {
+		ConnectionInfoCommand command = new ConnectionInfoCommand(threadManager);
+		if (command.runSync().isOK()) {
+			// TODO
+		}
+	}
+
+	public void backgroundTypecheckFile(String fileName) {
+		BackgroundTypecheckFileCommand command = new BackgroundTypecheckFileCommand(threadManager, fileName);
+		command.runAsync();
+	}
+
+	public void loadFile(String fileName) {
+		loadedFiles.add(fileName);
+		reloadFile(fileName);
+	}
+
+	public void reloadFile(String fileName) {
+		LoadCommand loadCommand = new LoadCommand(threadManager, fileName);
+		BackgroundTypecheckFileCommand typecheckCommand = new BackgroundTypecheckFileCommand(threadManager, fileName);
+		typecheckCommand.runAsyncAfter(loadCommand);
+		loadCommand.runAsync();
+	}
+
+	public void unloadFile(String fileName) {
+		// TODO Scion has no command for unloading yet!
+		loadedFiles.remove(fileName);
+	}
+
+	public String thingAtPoint(Location location) {
+      ThingAtPointCommand command = new ThingAtPointCommand(threadManager, location);
+      command.runSync();
+      if (command.getResult().isOK()) {
+    	  return command.getThing();
+      } else {
+    	  return null;
+      }
+	}
+
+	public Location firstDefinitionLocation(String name) {
+		NameDefinitionsCommand command = new NameDefinitionsCommand(threadManager, name);
+		command.runSync();
+		if (command.getResult().isOK() && command.isFound()) {
+			return command.getFirstLocation();
+		} else {
+			return null;
+		}
+	}
+
+}

net.sf.eclipsefp.haskell.scion.client/src/net/sf/eclipsefp/haskell/scion/client/ScionPlugin.java

@@ -24,21 +24,15 @@ public ScionPlugin() {
 	@Override
 	public void start(BundleContext context) throws Exception {
 		super.start(context);
-
 		resourceBundle = ResourceBundle.getBundle("plugin");
-
-		// Preload the server in anticipation of its use
-		Scion.initializeClient();
 	}
 
 	@Override
 	public void stop(BundleContext context) throws Exception {
-		Scion.dispose();
-
 		super.stop(context);
 	}
 
-	private static String getPluginId() {
+	public static String getPluginId() {
 		if (instance != null) {
 			return instance.getBundle().getSymbolicName();
 		} else {