org.eclipse.blockchain.ui/src/org/eclipse/blockchain/ui/preference/SolidityCompilerPreference.java - gerrit/secoblocks/secoblocks - Git at Google

 /*
  * Copyright (c) Robert Bosch GmbH. All rights reserved.
  */
 package org.eclipse.blockchain.ui.preference;

 import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.net.URL;
 import java.net.URLConnection;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;

 import org.eclipse.blockchain.core.BlockchainCore;
 import org.eclipse.blockchain.core.SecoBlocksPreferenceConstants;
 import org.eclipse.blockchain.ui.Activator;
 import org.eclipse.blockchain.ui.util.UnzipUtility;
 import org.eclipse.core.resources.ResourcesPlugin;
 import org.eclipse.core.runtime.IProgressMonitor;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.Platform;
 import org.eclipse.core.runtime.Status;
 import org.eclipse.core.runtime.SubMonitor;
 import org.eclipse.core.runtime.jobs.Job;
 import org.eclipse.core.runtime.preferences.InstanceScope;
 import org.eclipse.jface.dialogs.IDialogConstants;
 import org.eclipse.jface.dialogs.MessageDialog;
 import org.eclipse.jface.preference.PreferencePage;
 import org.eclipse.jface.viewers.IStructuredContentProvider;
 import org.eclipse.jface.viewers.IStructuredSelection;
 import org.eclipse.jface.viewers.ListViewer;
 import org.eclipse.jface.viewers.StructuredSelection;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.events.SelectionEvent;
 import org.eclipse.swt.events.SelectionListener;
 import org.eclipse.swt.layout.GridData;
 import org.eclipse.swt.layout.GridLayout;
 import org.eclipse.swt.widgets.Button;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Control;
 import org.eclipse.swt.widgets.DirectoryDialog;
 import org.eclipse.swt.widgets.Display;
 import org.eclipse.swt.widgets.Label;
 import org.eclipse.swt.widgets.Shell;
 import org.eclipse.swt.widgets.Text;
 import org.eclipse.ui.IWorkbench;
 import org.eclipse.ui.IWorkbenchPreferencePage;
 import org.eclipse.ui.PlatformUI;
 import org.osgi.service.prefs.BackingStoreException;


 /**
  * @author ADG5COB
  */
 public class SolidityCompilerPreference extends PreferencePage implements IWorkbenchPreferencePage {

   private Text solcPathText = null;
   String solidityCompilerPath;
   boolean added, removed;

   List<String> avaiableVersions = new ArrayList<>();
   List<String> selectedVersions = new ArrayList<>();

   /**
    * {@inheritDoc}
    */
   @Override
   public void init(final IWorkbench workbench) {

     this.solidityCompilerPath =
         Platform.getPreferencesService().getString(SecoBlocksPreferenceConstants.SECOBLOCKS_PREF_NODE,
             SecoBlocksPreferenceConstants.SOLIDITY_COMPILER_PREF_KEY, "", null);
     String list = Platform.getPreferencesService().getString(SecoBlocksPreferenceConstants.SECOBLOCKS_PREF_NODE,
         SecoBlocksPreferenceConstants.PREF_KEY_VersionList, null, null);
     if (list != null) {
       for (String version : list.split(",")) {
         this.avaiableVersions.add(version);
       }
     }
     list = Platform.getPreferencesService().getString(SecoBlocksPreferenceConstants.SECOBLOCKS_PREF_NODE,
         SecoBlocksPreferenceConstants.PREF_KEY_SelectedList, null, null);
     if (list != null) {
       for (String version : list.split(",")) {
         this.selectedVersions.add(version);
       }
     }
   }

   /**
    * {@inheritDoc}
    */
   @Override
   protected Control createContents(final Composite parent) {
     Composite container = new Composite(parent, SWT.None);
     container.setLayout(new GridLayout(3, false));
     GridData layoutData = new GridData(SWT.FILL, SWT.FILL, false, false);
     container.setLayoutData(layoutData);

     Label solcLabel = new Label(container, SWT.None);
     solcLabel.setLayoutData(new GridData(SWT.FILL, SWT.RIGHT, false, false));
     solcLabel.setText("Solidity Compiler Path");

     this.solcPathText = new Text(container, SWT.BORDER);
     this.solcPathText.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, false));
     this.solcPathText.setToolTipText("Please mention the filesystem path of solidity compiler to be downloaded");
     this.solcPathText.setText(this.solidityCompilerPath);

     Button compilerPathBrowseButton = new Button(container, SWT.PUSH);
     compilerPathBrowseButton.setText("Browse");
     compilerPathBrowseButton.setLayoutData(new GridData(SWT.FILL, SWT.RIGHT, false, false, 1, 1));

     compilerPathBrowseButton.addSelectionListener(new SelectionListener() {

       @Override
       public void widgetSelected(final SelectionEvent e) {
         DirectoryDialog solcCompilerPathDialog = new DirectoryDialog(parent.getShell());
         solcCompilerPathDialog.setFilterPath(System.getProperty("user.dir"));
         String selectedDir = solcCompilerPathDialog.open();
         if (selectedDir != null) {
           SolidityCompilerPreference.this.solcPathText.setText(selectedDir);
           SolidityCompilerPreference.this.solidityCompilerPath = selectedDir;
         }

       }

       @Override
       public void widgetDefaultSelected(final SelectionEvent e) {
         // do nothing
       }
     });


     Composite composite = new Composite(parent, SWT.NONE);
     GridData data = new GridData(SWT.FILL, SWT.FILL, false, false);
     data.horizontalSpan = 2;
     composite.setLayoutData(data);
     GridLayout layout = new GridLayout();
     layout.numColumns = 3;
     layout.marginHeight = 15;
     composite.setLayout(layout);

     Label candidatesLbl = new Label(composite, SWT.None);
     candidatesLbl.setText("Versions avaliable");
     candidatesLbl.setLayoutData(new GridData(SWT.CENTER, SWT.CENTER, false, true));


     Composite emptyContainer = new Composite(composite, SWT.None);
     layout = new GridLayout(1, false);
     emptyContainer.setLayout(layout);
     layoutData = new GridData(SWT.CENTER, SWT.CENTER, true, true);
     layout.horizontalSpacing = 20;
     layout.verticalSpacing = 30;
     emptyContainer.setLayoutData(layoutData);


     Label selected = new Label(composite, SWT.None);
     selected.setText("Versions to be downloaded");
     selected.setLayoutData(new GridData(SWT.CENTER, SWT.CENTER, false, true));

     ListViewer listViewer = new ListViewer(composite, SWT.SINGLE | SWT.H_SCROLL | SWT.V_SCROLL | SWT.BORDER);
     data = new GridData(GridData.FILL_BOTH);
     data.heightHint = convertHeightInCharsToPixels(10);
     data.widthHint = convertWidthInCharsToPixels(60);
     listViewer.getList().setLayoutData(data);
     listViewer.getList().setFont(parent.getFont());


     listViewer.setContentProvider(new IStructuredContentProvider() {

       @Override
       public Object[] getElements(final Object inputElement) {
         return ((ArrayList<String>) inputElement).toArray();
       }
     });

     if (this.avaiableVersions.isEmpty()) {
       this.avaiableVersions = new ArrayList<String>(Arrays.asList(SecoBlocksPreferenceConstants.versionList));
     }
     listViewer.setInput(this.avaiableVersions);

 // Set the initial selection
     listViewer.setSelection(new StructuredSelection(SecoBlocksPreferenceConstants.versionList[0]), true);

     Composite buttonContainer = new Composite(composite, SWT.None);
     layout = new GridLayout(1, false);
     buttonContainer.setLayout(layout);
     layoutData = new GridData(SWT.CENTER, SWT.CENTER, true, true);
     layout.horizontalSpacing = 20;
     layout.verticalSpacing = 30;
     buttonContainer.setLayoutData(layoutData);


     ListViewer listViewerSelected = new ListViewer(composite, SWT.SINGLE | SWT.H_SCROLL | SWT.V_SCROLL | SWT.BORDER);
     listViewerSelected.getList().setLayoutData(data);
     listViewerSelected.getList().setFont(parent.getFont());

     listViewerSelected.setContentProvider(new IStructuredContentProvider() {

       @Override
       public Object[] getElements(final Object inputElement) {
         return ((ArrayList<String>) inputElement).toArray();
       }
     });

     listViewerSelected.setInput(this.selectedVersions);

     Button sendRightButton = new Button(buttonContainer, SWT.BOLD);
     sendRightButton.setText(" > ");
     sendRightButton.addSelectionListener(new SelectionListener() {

       @Override
       public void widgetSelected(final SelectionEvent e) {
         IStructuredSelection s = (IStructuredSelection) listViewer.getSelection();
         String firstElement = (String) s.getFirstElement();
         if (firstElement != null) {
           SolidityCompilerPreference.this.avaiableVersions.remove(firstElement);
           SolidityCompilerPreference.this.selectedVersions.add(firstElement);
           listViewer.refresh(false);
           listViewerSelected.add(firstElement);
           SolidityCompilerPreference.this.added = true;
         }

       }

       @Override
       public void widgetDefaultSelected(final SelectionEvent e) {
         // TODO Auto-generated method stub

       }
     });


     Button sendLeftButton = new Button(buttonContainer, SWT.BOLD);
     sendLeftButton.setText(" < ");
     sendLeftButton.addSelectionListener(new SelectionListener() {

       @Override
       public void widgetSelected(final SelectionEvent e) {
         IStructuredSelection s = (IStructuredSelection) listViewerSelected.getSelection();
         String firstElement = (String) s.getFirstElement();
         if (firstElement != null) {
           SolidityCompilerPreference.this.selectedVersions.remove(firstElement);
           SolidityCompilerPreference.this.avaiableVersions.add(firstElement);
           listViewerSelected.refresh(false);
           listViewer.add(firstElement);
           SolidityCompilerPreference.this.removed = true;
         }

       }

       @Override
       public void widgetDefaultSelected(final SelectionEvent e) {
         // TODO Auto-generated method stub

       }
     });

     return parent;
   }

   /**
    * {@inheritDoc}
    */
   @Override
   public boolean performOk() {


     if (this.added) {
       Shell shell = PlatformUI.getWorkbench().getDisplay().getActiveShell();
       if (shell == null) {
         shell = new Shell(PlatformUI.getWorkbench().getDisplay());
       }
       MessageDialog messageBox = new MessageDialog(shell, "Download Information", null,
           "The selected compiler  versions will be downloaded in the specified location", MessageDialog.INFORMATION, 0,
           new String[] { IDialogConstants.OK_LABEL, IDialogConstants.CANCEL_LABEL });
       messageBox.setBlockOnOpen(true);
       int mbr = messageBox.open();
       if (mbr == IDialogConstants.CANCEL_ID) {
 // cancel
       }
       else if (mbr == IDialogConstants.OK_ID) {
         processDownload(this.selectedVersions);
       }

     }

     this.solidityCompilerPath = getSolText();
     InstanceScope.INSTANCE.getNode(SecoBlocksPreferenceConstants.SECOBLOCKS_PREF_NODE)
         .put(SecoBlocksPreferenceConstants.SOLIDITY_COMPILER_PREF_KEY, this.solidityCompilerPath);
     InstanceScope.INSTANCE.getNode(SecoBlocksPreferenceConstants.PREF_KEY_VersionList)
         .put(SecoBlocksPreferenceConstants.PREF_KEY_VersionList, String.join(",", this.avaiableVersions));
     InstanceScope.INSTANCE.getNode(SecoBlocksPreferenceConstants.PREF_KEY_SelectedList)
         .put(SecoBlocksPreferenceConstants.PREF_KEY_SelectedList, String.join(",", this.selectedVersions));
     try {
       InstanceScope.INSTANCE.getNode(SecoBlocksPreferenceConstants.SECOBLOCKS_PREF_NODE).flush();
     }
     catch (BackingStoreException e) {
       BlockchainCore.getInstance().logException(Activator.PLUGIN_ID, e.getMessage(), e);
     }
     return super.performOk();
   }

   private String getSolText() {
     List<String> solcPathList = new ArrayList<>();
     Display.getDefault().syncExec(() -> {
       solcPathList.add(this.solcPathText.getText());
     });
     return solcPathList.get(0);
   }


   /**
    * @param selectedVersion
    * @throws IOException
    */
   private void processDownload(final List<String> selectedVersion) {
     if (!this.solidityCompilerPath.isEmpty()) {
       Job job = new Job("Downloading Complier Packages") {

         @Override
         public IStatus run(final IProgressMonitor monitor) {
           SubMonitor subMonitor = SubMonitor.convert(monitor);

           for (String version : selectedVersion) {
             String urlString =
                 "https://github.com/ethereum/solidity/releases/download/" + version + "/solidity-windows.zip";
             version = version.replace(".", "_");
             java.io.File file =
                 new java.io.File(SolidityCompilerPreference.this.solidityCompilerPath + File.separator + version);
             file.getParentFile().setReadable(true);
             file.mkdir();
             file.setReadable(true);
             file.getParentFile().mkdirs();
             try {
               URL website = new URL(urlString.trim());
               String zipFile = file + File.separator + "solidity-windows.zip";
               URLConnection connection = website.openConnection();
               InputStream reader = website.openStream();
               subMonitor.beginTask(getName(), connection.getContentLength());
               byte[] buffer = new byte[102400];
               int totalBytesRead = 0;
               int bytesRead = 0;
               try (FileOutputStream writer = new FileOutputStream(zipFile, true)) {
                 while ((bytesRead = reader.read(buffer)) > 0) {
                   writer.write(buffer, 0, bytesRead);
                   buffer = new byte[102400];
                   totalBytesRead += bytesRead;
                   subMonitor.newChild(1);
                 }
                 writer.close();
                 reader.close();
               }
               // unzip the file
               UnzipUtility.unzip(zipFile, file.getCanonicalPath());
               subMonitor.done();
             }
             catch (Exception e) {
               return new Status(IStatus.ERROR, "download",
                   "The network proxy has to be checked. Please go to Window -> Preferences->General-> NetworkConnections.\\n Please set the correct proxy to download the selected complier versions");
             }
           }
           Display.getDefault().syncExec(() -> {
             MessageDialog messageBox = new MessageDialog(Display.getDefault().getActiveShell(), "Download Information",
                 null, "Downloaded successfully", MessageDialog.INFORMATION, 0,
                 new String[] { IDialogConstants.OK_LABEL });
             messageBox.setBlockOnOpen(true);
             messageBox.open();
           });

           return new Status(IStatus.OK, "download", "Successfully downloaded");
         }
       };
       job.setRule(ResourcesPlugin.getWorkspace().getRoot());
       job.setUser(true);
       job.schedule();

     }
   }


 }
	/*
	* Copyright (c) Robert Bosch GmbH. All rights reserved.
	*/
	package org.eclipse.blockchain.ui.preference;

	import java.io.File;
	import java.io.FileOutputStream;
	import java.io.IOException;
	import java.io.InputStream;
	import java.net.URL;
	import java.net.URLConnection;
	import java.util.ArrayList;
	import java.util.Arrays;
	import java.util.List;

	import org.eclipse.blockchain.core.BlockchainCore;
	import org.eclipse.blockchain.core.SecoBlocksPreferenceConstants;
	import org.eclipse.blockchain.ui.Activator;
	import org.eclipse.blockchain.ui.util.UnzipUtility;
	import org.eclipse.core.resources.ResourcesPlugin;
	import org.eclipse.core.runtime.IProgressMonitor;
	import org.eclipse.core.runtime.IStatus;
	import org.eclipse.core.runtime.Platform;
	import org.eclipse.core.runtime.Status;
	import org.eclipse.core.runtime.SubMonitor;
	import org.eclipse.core.runtime.jobs.Job;
	import org.eclipse.core.runtime.preferences.InstanceScope;
	import org.eclipse.jface.dialogs.IDialogConstants;
	import org.eclipse.jface.dialogs.MessageDialog;
	import org.eclipse.jface.preference.PreferencePage;
	import org.eclipse.jface.viewers.IStructuredContentProvider;
	import org.eclipse.jface.viewers.IStructuredSelection;
	import org.eclipse.jface.viewers.ListViewer;
	import org.eclipse.jface.viewers.StructuredSelection;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.events.SelectionEvent;
	import org.eclipse.swt.events.SelectionListener;
	import org.eclipse.swt.layout.GridData;
	import org.eclipse.swt.layout.GridLayout;
	import org.eclipse.swt.widgets.Button;
	import org.eclipse.swt.widgets.Composite;
	import org.eclipse.swt.widgets.Control;
	import org.eclipse.swt.widgets.DirectoryDialog;
	import org.eclipse.swt.widgets.Display;
	import org.eclipse.swt.widgets.Label;
	import org.eclipse.swt.widgets.Shell;
	import org.eclipse.swt.widgets.Text;
	import org.eclipse.ui.IWorkbench;
	import org.eclipse.ui.IWorkbenchPreferencePage;
	import org.eclipse.ui.PlatformUI;
	import org.osgi.service.prefs.BackingStoreException;


	/**
	* @author ADG5COB
	*/
	public class SolidityCompilerPreference extends PreferencePage implements IWorkbenchPreferencePage {

	private Text solcPathText = null;
	String solidityCompilerPath;
	boolean added, removed;

	List<String> avaiableVersions = new ArrayList<>();
	List<String> selectedVersions = new ArrayList<>();

	/**
	* {@inheritDoc}
	*/
	@Override
	public void init(final IWorkbench workbench) {

	this.solidityCompilerPath =
	Platform.getPreferencesService().getString(SecoBlocksPreferenceConstants.SECOBLOCKS_PREF_NODE,
	SecoBlocksPreferenceConstants.SOLIDITY_COMPILER_PREF_KEY, "", null);
	String list = Platform.getPreferencesService().getString(SecoBlocksPreferenceConstants.SECOBLOCKS_PREF_NODE,
	SecoBlocksPreferenceConstants.PREF_KEY_VersionList, null, null);
	if (list != null) {
	for (String version : list.split(",")) {
	this.avaiableVersions.add(version);
	}
	}
	list = Platform.getPreferencesService().getString(SecoBlocksPreferenceConstants.SECOBLOCKS_PREF_NODE,
	SecoBlocksPreferenceConstants.PREF_KEY_SelectedList, null, null);
	if (list != null) {
	for (String version : list.split(",")) {
	this.selectedVersions.add(version);
	}
	}
	}

	/**
	* {@inheritDoc}
	*/
	@Override
	protected Control createContents(final Composite parent) {
	Composite container = new Composite(parent, SWT.None);
	container.setLayout(new GridLayout(3, false));
	GridData layoutData = new GridData(SWT.FILL, SWT.FILL, false, false);
	container.setLayoutData(layoutData);

	Label solcLabel = new Label(container, SWT.None);
	solcLabel.setLayoutData(new GridData(SWT.FILL, SWT.RIGHT, false, false));
	solcLabel.setText("Solidity Compiler Path");

	this.solcPathText = new Text(container, SWT.BORDER);
	this.solcPathText.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, false));
	this.solcPathText.setToolTipText("Please mention the filesystem path of solidity compiler to be downloaded");
	this.solcPathText.setText(this.solidityCompilerPath);

	Button compilerPathBrowseButton = new Button(container, SWT.PUSH);
	compilerPathBrowseButton.setText("Browse");
	compilerPathBrowseButton.setLayoutData(new GridData(SWT.FILL, SWT.RIGHT, false, false, 1, 1));

	compilerPathBrowseButton.addSelectionListener(new SelectionListener() {

	@Override
	public void widgetSelected(final SelectionEvent e) {
	DirectoryDialog solcCompilerPathDialog = new DirectoryDialog(parent.getShell());
	solcCompilerPathDialog.setFilterPath(System.getProperty("user.dir"));
	String selectedDir = solcCompilerPathDialog.open();
	if (selectedDir != null) {
	SolidityCompilerPreference.this.solcPathText.setText(selectedDir);
	SolidityCompilerPreference.this.solidityCompilerPath = selectedDir;
	}

	}

	@Override
	public void widgetDefaultSelected(final SelectionEvent e) {
	// do nothing
	}
	});


	Composite composite = new Composite(parent, SWT.NONE);
	GridData data = new GridData(SWT.FILL, SWT.FILL, false, false);
	data.horizontalSpan = 2;
	composite.setLayoutData(data);
	GridLayout layout = new GridLayout();
	layout.numColumns = 3;
	layout.marginHeight = 15;
	composite.setLayout(layout);

	Label candidatesLbl = new Label(composite, SWT.None);
	candidatesLbl.setText("Versions avaliable");
	candidatesLbl.setLayoutData(new GridData(SWT.CENTER, SWT.CENTER, false, true));


	Composite emptyContainer = new Composite(composite, SWT.None);
	layout = new GridLayout(1, false);
	emptyContainer.setLayout(layout);
	layoutData = new GridData(SWT.CENTER, SWT.CENTER, true, true);
	layout.horizontalSpacing = 20;
	layout.verticalSpacing = 30;
	emptyContainer.setLayoutData(layoutData);


	Label selected = new Label(composite, SWT.None);
	selected.setText("Versions to be downloaded");
	selected.setLayoutData(new GridData(SWT.CENTER, SWT.CENTER, false, true));

	ListViewer listViewer = new ListViewer(composite, SWT.SINGLE \| SWT.H_SCROLL \| SWT.V_SCROLL \| SWT.BORDER);
	data = new GridData(GridData.FILL_BOTH);
	data.heightHint = convertHeightInCharsToPixels(10);
	data.widthHint = convertWidthInCharsToPixels(60);
	listViewer.getList().setLayoutData(data);
	listViewer.getList().setFont(parent.getFont());


	listViewer.setContentProvider(new IStructuredContentProvider() {

	@Override
	public Object[] getElements(final Object inputElement) {
	return ((ArrayList<String>) inputElement).toArray();
	}
	});

	if (this.avaiableVersions.isEmpty()) {
	this.avaiableVersions = new ArrayList<String>(Arrays.asList(SecoBlocksPreferenceConstants.versionList));
	}
	listViewer.setInput(this.avaiableVersions);

	// Set the initial selection
	listViewer.setSelection(new StructuredSelection(SecoBlocksPreferenceConstants.versionList[0]), true);

	Composite buttonContainer = new Composite(composite, SWT.None);
	layout = new GridLayout(1, false);
	buttonContainer.setLayout(layout);
	layoutData = new GridData(SWT.CENTER, SWT.CENTER, true, true);
	layout.horizontalSpacing = 20;
	layout.verticalSpacing = 30;
	buttonContainer.setLayoutData(layoutData);


	ListViewer listViewerSelected = new ListViewer(composite, SWT.SINGLE \| SWT.H_SCROLL \| SWT.V_SCROLL \| SWT.BORDER);
	listViewerSelected.getList().setLayoutData(data);
	listViewerSelected.getList().setFont(parent.getFont());

	listViewerSelected.setContentProvider(new IStructuredContentProvider() {

	@Override
	public Object[] getElements(final Object inputElement) {
	return ((ArrayList<String>) inputElement).toArray();
	}
	});

	listViewerSelected.setInput(this.selectedVersions);

	Button sendRightButton = new Button(buttonContainer, SWT.BOLD);
	sendRightButton.setText(" > ");
	sendRightButton.addSelectionListener(new SelectionListener() {

	@Override
	public void widgetSelected(final SelectionEvent e) {
	IStructuredSelection s = (IStructuredSelection) listViewer.getSelection();
	String firstElement = (String) s.getFirstElement();
	if (firstElement != null) {
	SolidityCompilerPreference.this.avaiableVersions.remove(firstElement);
	SolidityCompilerPreference.this.selectedVersions.add(firstElement);
	listViewer.refresh(false);
	listViewerSelected.add(firstElement);
	SolidityCompilerPreference.this.added = true;
	}

	}

	@Override
	public void widgetDefaultSelected(final SelectionEvent e) {
	// TODO Auto-generated method stub

	}
	});


	Button sendLeftButton = new Button(buttonContainer, SWT.BOLD);
	sendLeftButton.setText(" < ");
	sendLeftButton.addSelectionListener(new SelectionListener() {

	@Override
	public void widgetSelected(final SelectionEvent e) {
	IStructuredSelection s = (IStructuredSelection) listViewerSelected.getSelection();
	String firstElement = (String) s.getFirstElement();
	if (firstElement != null) {
	SolidityCompilerPreference.this.selectedVersions.remove(firstElement);
	SolidityCompilerPreference.this.avaiableVersions.add(firstElement);
	listViewerSelected.refresh(false);
	listViewer.add(firstElement);
	SolidityCompilerPreference.this.removed = true;
	}

	}

	@Override
	public void widgetDefaultSelected(final SelectionEvent e) {
	// TODO Auto-generated method stub

	}
	});

	return parent;
	}

	/**
	* {@inheritDoc}
	*/
	@Override
	public boolean performOk() {


	if (this.added) {
	Shell shell = PlatformUI.getWorkbench().getDisplay().getActiveShell();
	if (shell == null) {
	shell = new Shell(PlatformUI.getWorkbench().getDisplay());
	}
	MessageDialog messageBox = new MessageDialog(shell, "Download Information", null,
	"The selected compiler versions will be downloaded in the specified location", MessageDialog.INFORMATION, 0,
	new String[] { IDialogConstants.OK_LABEL, IDialogConstants.CANCEL_LABEL });
	messageBox.setBlockOnOpen(true);
	int mbr = messageBox.open();
	if (mbr == IDialogConstants.CANCEL_ID) {
	// cancel
	}
	else if (mbr == IDialogConstants.OK_ID) {
	processDownload(this.selectedVersions);
	}

	}

	this.solidityCompilerPath = getSolText();
	InstanceScope.INSTANCE.getNode(SecoBlocksPreferenceConstants.SECOBLOCKS_PREF_NODE)
	.put(SecoBlocksPreferenceConstants.SOLIDITY_COMPILER_PREF_KEY, this.solidityCompilerPath);
	InstanceScope.INSTANCE.getNode(SecoBlocksPreferenceConstants.PREF_KEY_VersionList)
	.put(SecoBlocksPreferenceConstants.PREF_KEY_VersionList, String.join(",", this.avaiableVersions));
	InstanceScope.INSTANCE.getNode(SecoBlocksPreferenceConstants.PREF_KEY_SelectedList)
	.put(SecoBlocksPreferenceConstants.PREF_KEY_SelectedList, String.join(",", this.selectedVersions));
	try {
	InstanceScope.INSTANCE.getNode(SecoBlocksPreferenceConstants.SECOBLOCKS_PREF_NODE).flush();
	}
	catch (BackingStoreException e) {
	BlockchainCore.getInstance().logException(Activator.PLUGIN_ID, e.getMessage(), e);
	}
	return super.performOk();
	}

	private String getSolText() {
	List<String> solcPathList = new ArrayList<>();
	Display.getDefault().syncExec(() -> {
	solcPathList.add(this.solcPathText.getText());
	});
	return solcPathList.get(0);
	}


	/**
	* @param selectedVersion
	* @throws IOException
	*/
	private void processDownload(final List<String> selectedVersion) {
	if (!this.solidityCompilerPath.isEmpty()) {
	Job job = new Job("Downloading Complier Packages") {

	@Override
	public IStatus run(final IProgressMonitor monitor) {
	SubMonitor subMonitor = SubMonitor.convert(monitor);

	for (String version : selectedVersion) {
	String urlString =
	"https://github.com/ethereum/solidity/releases/download/" + version + "/solidity-windows.zip";
	version = version.replace(".", "_");
	java.io.File file =
	new java.io.File(SolidityCompilerPreference.this.solidityCompilerPath + File.separator + version);
	file.getParentFile().setReadable(true);
	file.mkdir();
	file.setReadable(true);
	file.getParentFile().mkdirs();
	try {
	URL website = new URL(urlString.trim());
	String zipFile = file + File.separator + "solidity-windows.zip";
	URLConnection connection = website.openConnection();
	InputStream reader = website.openStream();
	subMonitor.beginTask(getName(), connection.getContentLength());
	byte[] buffer = new byte[102400];
	int totalBytesRead = 0;
	int bytesRead = 0;
	try (FileOutputStream writer = new FileOutputStream(zipFile, true)) {
	while ((bytesRead = reader.read(buffer)) > 0) {
	writer.write(buffer, 0, bytesRead);
	buffer = new byte[102400];
	totalBytesRead += bytesRead;
	subMonitor.newChild(1);
	}
	writer.close();
	reader.close();
	}
	// unzip the file
	UnzipUtility.unzip(zipFile, file.getCanonicalPath());
	subMonitor.done();
	}
	catch (Exception e) {
	return new Status(IStatus.ERROR, "download",
	"The network proxy has to be checked. Please go to Window -> Preferences->General-> NetworkConnections.\\n Please set the correct proxy to download the selected complier versions");
	}
	}
	Display.getDefault().syncExec(() -> {
	MessageDialog messageBox = new MessageDialog(Display.getDefault().getActiveShell(), "Download Information",
	null, "Downloaded successfully", MessageDialog.INFORMATION, 0,
	new String[] { IDialogConstants.OK_LABEL });
	messageBox.setBlockOnOpen(true);
	messageBox.open();
	});

	return new Status(IStatus.OK, "download", "Successfully downloaded");
	}
	};
	job.setRule(ResourcesPlugin.getWorkspace().getRoot());
	job.setUser(true);
	job.schedule();

	}
	}


	}