eclipse plugin: Recreate the Core Library link...

...if we change the project's wesnoth install

utils/umc_dev/org.wesnoth/src/org/wesnoth/installs/WesnothInstallsUtils.java

@@ -200,6 +200,11 @@ public class WesnothInstallsUtils
             if( WorkspaceUtils.checkPathsAreSet( installName, true ) ) {
                 // replace current install with the default
                 setInstallNameForResource( resource, installName );
+
+                // re-create the core library link
+                ProjectUtils.createCoreLibraryFolder( resource.getProject( ),
+                    IResource.NONE );
+
                 return true;
             }
 

utils/umc_dev/org.wesnoth/src/org/wesnoth/preferences/Preferences.java

@@ -12,6 +12,7 @@ import java.util.HashMap;
 import java.util.Map;
 
 import org.eclipse.core.runtime.IPath;
+import org.eclipse.core.runtime.Path;
 import org.eclipse.core.runtime.preferences.AbstractPreferenceInitializer;
 import org.eclipse.jface.preference.IPreferenceStore;
 
@@ -233,6 +234,16 @@ public class Preferences extends AbstractPreferenceInitializer
             return getWorkingDir( ) + "data/core/"; //$NON-NLS-1$
         }
 
+        /**
+         * Returns the 'data/core' directory as a Path variable
+         * 
+         * @return Returns the 'data/core' directory
+         */
+        public Path getCoreDirPath( )
+        {
+            return new Path( getCoreDir( ) );
+        }
+
         /**
          * Returns the <b>schema.cfg</b> file path
          * 

utils/umc_dev/org.wesnoth/src/org/wesnoth/projects/ProjectCache.java

@@ -76,6 +76,16 @@ public class ProjectCache implements Serializable
             .getMacrosLocation( project ) );
     }
 
+    /**
+     * Returns the associated project for this cache
+     * 
+     * @return An IProject instance
+     */
+    public IProject getProject( )
+    {
+        return project_;
+    }
+
     /**
      * Gets the properties map for this project.
      * 

utils/umc_dev/org.wesnoth/src/org/wesnoth/projects/ProjectUtils.java

@@ -20,6 +20,8 @@ import org.eclipse.core.resources.IWorkspaceRoot;
 import org.eclipse.core.resources.ResourcesPlugin;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IProgressMonitor;
+import org.eclipse.core.runtime.IStatus;
+import org.eclipse.core.runtime.NullProgressMonitor;
 import org.eclipse.core.runtime.Path;
 
 import org.wesnoth.Constants;
@@ -75,6 +77,52 @@ public class ProjectUtils
         return cache;
     }
 
+    /**
+     * Creates a folder that link to the project's wesnoth installation's
+     * 'data/core' directory
+     * 
+     * @param updateFlags
+     *        bit-wise or of update flag constants
+     *        (IResource.ALLOW_MISSING_LOCAL, IResource.REPLACE,
+     *        IResource.BACKGROUND_REFRESH, and IResource.HIDDEN)
+     * @param project
+     *        The project to create the link for
+     * @return True if the creation was successfully, false otherwise
+     */
+    public static boolean createCoreLibraryFolder( IProject project,
+        int updateFlags )
+    {
+        ProjectCache cache = getCacheForProject( project );
+        Paths paths = Preferences.getPaths( cache.getInstallName( ) );
+        IFolder coreLibrary = project
+            .getFolder( WesnothProjectsExplorer.CORE_LIBRARY_NAME );
+
+        if( ResourcesPlugin.getWorkspace( ).validateLinkLocation( coreLibrary,
+            paths.getCoreDirPath( ) ).getCode( ) != IStatus.ERROR ) {
+            try {
+                if( coreLibrary.exists( ) ) {
+                    coreLibrary.delete( true, new NullProgressMonitor( ) );
+                }
+
+                coreLibrary
+                    .createLink( paths.getCoreDirPath( ), updateFlags,
+                        new NullProgressMonitor( ) );
+            } catch( CoreException e ) {
+                Logger.getInstance( ).logException( e );
+                return false;
+            }
+        }
+        else {
+            Logger.getInstance( ).log(
+                "Couldn't create link on:" + paths.getCoreDir( )
+                    + "; project: " + project.getName( ),
+                "Cannot create the Wesnoth Core Library folder for project "
+                    + project.getName( ) + "!" );
+        }
+
+        return true;
+    }
+
     /**
      * Creates a new wesnoth project with the specified name
      * and on the specified location on disk
@@ -200,10 +248,7 @@ public class ProjectUtils
             monitor.worked( 10 );
 
             // create the Core library link
-            IFolder coreLibrary = handle
-                .getFolder( WesnothProjectsExplorer.CORE_LIBRARY_NAME );
-            coreLibrary.createLink( new Path( paths.getCoreDir( ) ),
-                IResource.NONE, monitor );
+            createCoreLibraryFolder( handle, IResource.NONE );
             monitor.worked( 10 );
 
             // save the install name

utils/umc_dev/org.wesnoth/src/org/wesnoth/propertypages/WesnothProjectPage.java

@@ -3,6 +3,7 @@ package org.wesnoth.propertypages;
 import java.util.List;
 
 import org.eclipse.core.resources.IProject;
+import org.eclipse.core.resources.IResource;
 import org.eclipse.core.runtime.IAdaptable;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.layout.FillLayout;
@@ -24,12 +25,14 @@ import org.wesnoth.projects.ProjectUtils;
 public class WesnothProjectPage extends PropertyPage
 {
     private Combo        cmbInstall_;
-    private ProjectCache currProjectCache_;
+    private ProjectCache currentProjectCache_;
+    private String       currentInstall_;
 
     public WesnothProjectPage( )
     {
-        currProjectCache_ = null;
+        currentProjectCache_ = null;
         cmbInstall_ = null;
+        currentInstall_ = null;
     }
 
     @Override
@@ -42,7 +45,8 @@ public class WesnothProjectPage extends PropertyPage
 
         IProject selectedProject = ( IProject ) selectedElement;
 
-        currProjectCache_ = ProjectUtils.getCacheForProject( selectedProject );
+        currentProjectCache_ = ProjectUtils
+            .getCacheForProject( selectedProject );
 
         Composite newComposite = new Composite( parent, 0 );
         newComposite.setLayout( new FillLayout( SWT.VERTICAL ) );
@@ -64,7 +68,7 @@ public class WesnothProjectPage extends PropertyPage
         List< WesnothInstall > installs = WesnothInstallsUtils.getInstalls( );
 
         boolean foundInstallInList = false;
-        String installName = currProjectCache_.getInstallName( );
+        String installName = currentProjectCache_.getInstallName( );
 
         for( WesnothInstall wesnothInstall: installs ) {
             cmbInstall_.add( wesnothInstall.getName( ) );
@@ -72,6 +76,7 @@ public class WesnothProjectPage extends PropertyPage
             // current install is default?
             if( wesnothInstall.getName( ).equalsIgnoreCase( installName ) ) {
                 cmbInstall_.select( cmbInstall_.getItemCount( ) - 1 );
+                currentInstall_ = wesnothInstall.getName( );
                 foundInstallInList = true;
             }
         }
@@ -87,9 +92,16 @@ public class WesnothProjectPage extends PropertyPage
     @Override
     public boolean performOk( )
     {
+        String selectedInstall = cmbInstall_.getText( );
         // save settings.
-        if( currProjectCache_ != null && ! cmbInstall_.getText( ).isEmpty( ) ) {
-            currProjectCache_.setInstallName( cmbInstall_.getText( ) );
+        if( currentProjectCache_ != null && ! selectedInstall.isEmpty( ) ) {
+            currentProjectCache_.setInstallName( selectedInstall );
+
+            if( ! selectedInstall.equals( currentInstall_ ) ) {
+                // relink the data directory
+                ProjectUtils.createCoreLibraryFolder( currentProjectCache_
+                    .getProject( ), IResource.BACKGROUND_REFRESH );
+            }
         }
 
         return true;