package org.eparapher.rcp.views;

import java.security.KeyStoreException;
import java.security.cert.X509Certificate;
import java.util.Iterator;

import org.apache.log4j.Logger;
import org.eclipse.jface.action.Action;
import org.eclipse.jface.action.IMenuListener;
import org.eclipse.jface.action.IMenuManager;
import org.eclipse.jface.action.IToolBarManager;
import org.eclipse.jface.action.MenuManager;
import org.eclipse.jface.action.Separator;
import org.eclipse.jface.viewers.ColumnWeightData;
import org.eclipse.jface.viewers.DoubleClickEvent;
import org.eclipse.jface.viewers.IDoubleClickListener;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.IStructuredContentProvider;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.ITableLabelProvider;
import org.eclipse.jface.viewers.LabelProvider;
import org.eclipse.jface.viewers.TableLayout;
import org.eclipse.jface.viewers.TableViewer;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.jface.viewers.ViewerComparator;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Menu;
import org.eclipse.swt.widgets.Table;
import org.eclipse.swt.widgets.TableColumn;
import org.eclipse.ui.IActionBars;
import org.eclipse.ui.IViewPart;
import org.eclipse.ui.IWorkbenchActionConstants;
import org.eclipse.ui.part.ViewPart;
import org.eparapher.core.EParapherManager;
import org.eparapher.core.crypto.EPKeystoreManager;
import org.eparapher.core.crypto.cert.CertificateInfo;
import org.eparapher.core.crypto.keystore.KeystoreEntry;
import org.eparapher.rcp.dialog.CertificateViewerDialog;
import org.eparapher.rcp.tools.GUIIcons;
import org.eparapher.rcp.tools.RCPGUI;


public abstract class AbstractCertificateView extends ViewPart {

	private static Logger log = Logger.getLogger(AbstractCertificateView.class);
	
	protected TableViewer viewer;
	protected Action      importAction;
	protected Action      exportAction;
	protected Action      delecteAction;
	protected Action      refreshAction;
	protected Action      doubleClickAction;
	
	//private static DateFormat dateFormat = DateFormat.getDateInstance(DateFormat.FULL, Locale.getDefault());
	/*
	 * The content provider class is responsible for
	 * providing objects to the view. It can wrap
	 * existing objects in adapters or simply return
	 * objects as-is. These objects may be sensitive
	 * to the current input of the view, or ignore
	 * it and always show the same content 
	 * (like Task List, for example).
	 */
	 
	class ViewContentProvider implements IStructuredContentProvider {
		
		public void inputChanged(Viewer v, Object oldInput, Object newInput) {
		}
		public void dispose() {
		}
		public Object[] getElements(Object parent) {
			return getKeystoreEntries();
		}
	}
	class ViewLabelProvider extends LabelProvider implements ITableLabelProvider {
		public String getColumnText(Object obj, int index) {

			if (obj==null)
				return "";
			
			KeystoreEntry certchain = (KeystoreEntry) obj;
			
			X509Certificate userCert = null;
			if (certchain.getCertificateChain() == null) {
				if (index==4)
					return "Secret Key";
				if (index==7)
					return certchain.getKeystoreAlias();
				return "--";
			}
			userCert = certchain.getCertificateChain()[0];
			
			switch (index) {
				case 0:	return CertificateInfo.getSubjectAsShortText(userCert);
				case 1: return CertificateInfo.getIssuerAsShortText(userCert);
				case 2:	return CertificateInfo.getNotBeforeAsText( userCert );
				case 3:	return CertificateInfo.getNotAfterAsText( userCert );
				case 4: return CertificateInfo.getPublicKeyInfo( userCert.getPublicKey() );
				case 5: return CertificateInfo.getKeyUsageAsText(userCert);
				case 6:	return CertificateInfo.getExtendedKeyUsageAsText(userCert);
				case 7:	return certchain.getKeystoreAlias();
				default: break;
			}
			return "";
		}
		public Image getColumnImage(Object obj, int index) {
			if (index == 0)
				return getImage(obj);
			return null;
		}
		
		public Image getImage(Object obj) {
			return 	getCertificateImage(obj);
		}
	}

	class NameComparator extends ViewerComparator {
	    public int compare(Viewer viewer, Object e1, Object e2) {
	    	KeystoreEntry k1 = (KeystoreEntry) e1; 
	    	KeystoreEntry k2 = (KeystoreEntry) e2; 
	    	if (k1.getCertificateChain()==null || k2.getCertificateChain()==null ||
	    		k1.getCertificateChain().length ==0 || k2.getCertificateChain().length ==0)
	    	return 1;
	    	String s1 = CertificateInfo.getSubjectAsShortText(k1.getCertificateChain()[0]);
	    	String s2 = CertificateInfo.getSubjectAsShortText(k2.getCertificateChain()[0]);
			int compare = getComparator().compare(s1, s2);
			return compare;
	    }
	    public boolean isSorterProperty(Object element, String property) {
	        return false;
	    }
	}

	/**
	 * This is a callback that will allow us
	 * to create the viewer and initialize it.
	 */
	public void createPartControl(Composite parent) {

		viewer = new TableViewer(createTable(parent));
		viewer.setContentProvider(new ViewContentProvider());
		viewer.setLabelProvider(new ViewLabelProvider());
		viewer.setComparator(new NameComparator());
		viewer.setInput(getViewSite());

		makeActions();
		hookContextMenu();
		hookDoubleClickAction();
		contributeToActionBars();
	}

	private Table createTable(Composite parent) {
		//Table struture
		Table table = new Table(parent, SWT.H_SCROLL | SWT.V_SCROLL | SWT.MULTI |  SWT.FULL_SELECTION);
		table.setLinesVisible(true);
		table.setHeaderVisible(true);
		
		TableLayout layout = new TableLayout();
		layout.addColumnData(new ColumnWeightData(1, 100, true));
		layout.addColumnData(new ColumnWeightData(1, 100, true));
		layout.addColumnData(new ColumnWeightData(1, 100, true));
		layout.addColumnData(new ColumnWeightData(1, 100, true));
		layout.addColumnData(new ColumnWeightData(1, 100, true));
		layout.addColumnData(new ColumnWeightData(1, 100, true));
		layout.addColumnData(new ColumnWeightData(1, 100, true));
		table.setLayout(layout);

		TableColumn nameColumn = new TableColumn(table, SWT.NONE);
		nameColumn.setText("Delivered to");
		nameColumn.setWidth(70);
		nameColumn.setMoveable(true);

		TableColumn issuerCNColumn = new TableColumn(table, SWT.NONE);
		issuerCNColumn.setText("Delivered by");
		issuerCNColumn.setWidth(70);
		issuerCNColumn.setMoveable(true);
		
		TableColumn deliveryDateColumn = new TableColumn(table, SWT.NONE);
		deliveryDateColumn.setText("Valid from");
		deliveryDateColumn.setWidth(70);
		deliveryDateColumn.setMoveable(true);
		
		TableColumn expiryDateColumn = new TableColumn(table, SWT.NONE);
		expiryDateColumn.setText("Expires on");
		expiryDateColumn.setWidth(70);
		expiryDateColumn.setMoveable(true);

		TableColumn keyColumn = new TableColumn(table, SWT.NONE);
		keyColumn.setText("Key");
		keyColumn.setWidth(120);
		keyColumn.setMoveable(true);
		
		TableColumn keyusageColumn = new TableColumn(table, SWT.NONE);
		keyusageColumn.setText("Key Usage");
		keyusageColumn.setWidth(120);
		keyusageColumn.setMoveable(true);
		
		TableColumn issuerDNColumn = new TableColumn(table, SWT.NONE);
		issuerDNColumn.setText("Extended KeyUsage");
		issuerDNColumn.setWidth(120);
		issuerDNColumn.setMoveable(true);

		TableColumn aliasColumn = new TableColumn(table, SWT.NONE);
		aliasColumn.setText("Alias");
		aliasColumn.setWidth(60);
		aliasColumn.setMoveable(true);
		
		return table;
	}
	private void hookContextMenu() {
		MenuManager menuMgr = new MenuManager("#PopupMenu");
		menuMgr.setRemoveAllWhenShown(true);
		menuMgr.addMenuListener(new IMenuListener() {
			public void menuAboutToShow(IMenuManager manager) {
				fillContextMenu(manager);
			}
		});
		Menu menu = menuMgr.createContextMenu(viewer.getControl());
		viewer.getControl().setMenu(menu);
		getSite().registerContextMenu(menuMgr, viewer);
	}

	private void contributeToActionBars() {
		IActionBars bars = getViewSite().getActionBars();
		//fillLocalPullDown(bars.getMenuManager());
		fillLocalToolBar(bars.getToolBarManager());
	}

	protected void fillLocalPullDown(IMenuManager manager) {
		manager.add(importAction);
		manager.add(exportAction);
	}

	protected void fillContextMenu(IMenuManager manager) {
		manager.add(delecteAction);
		manager.add(new Separator());
		manager.add(importAction);
		manager.add(exportAction);
		manager.add(new Separator());
		manager.add(refreshAction);
		// Other plug-ins can contribute there actions here
		manager.add(new Separator(IWorkbenchActionConstants.MB_ADDITIONS));
	}
	
	protected void fillLocalToolBar(IToolBarManager manager) {
		manager.add(refreshAction);
		manager.add(new Separator());
		manager.add(importAction);
		manager.add(exportAction);
	}

	protected void makeActions() {

		delecteAction = new DeleteAction(this);
		
		
		refreshAction =  new RefreshAction();
		
		doubleClickAction = new DoubleClickAction();
	}

	private void hookDoubleClickAction() {
		viewer.addDoubleClickListener(new IDoubleClickListener() {
			public void doubleClick(DoubleClickEvent event) {
				doubleClickAction.run();
			}
		});
	}

	/**
	 * Passing the focus request to the viewer's control.
	 */
	public void setFocus() {
		viewer.getControl().setFocus();
	}
	/**
	 * Refresh the view.
	 */
	public void refreshView() {
		//refresh the view
		if (viewer!=null)
			viewer.refresh();
	}
	/**
	 * Passing the focus request to the viewer's control.
	 */
	protected abstract Object[] getKeystoreEntries();
	
	protected abstract Image getCertificateImage(Object obj);
	
	protected String[] getSelectedAlias() {
		ISelection selection = viewer.getSelection();
		int size = ((IStructuredSelection)selection).size();
		String[] selected_aliases = new String[size];
		int i=0;
		IStructuredSelection struct_sel = (IStructuredSelection)selection;
		for (Iterator<KeystoreEntry> iterator = struct_sel.iterator(); iterator.hasNext();) {
			KeystoreEntry type = iterator.next();
			selected_aliases[i++] = type.getKeystoreAlias();
		}
		return selected_aliases;
	}

	class RefreshAction extends Action {
		protected RefreshAction() {
			setText("Re&fresh");
			setToolTipText("Refresh the Tree for added/removed files");
			setImageDescriptor(GUIIcons.REFRESH_ICON);
			setAccelerator(SWT.F5);
		}
		public void run() {
			viewer.refresh();
		}
	}
	
	class DoubleClickAction extends Action {
			public void run() {
				ISelection selection = viewer.getSelection();
				Object obj = ((IStructuredSelection)selection).getFirstElement();
				if (obj instanceof KeystoreEntry) {
					KeystoreEntry ke = (KeystoreEntry) obj; 
					if (ke.getCertificateChain()!=null) {
						CertificateViewerDialog cvg = new CertificateViewerDialog(ke.getCertificateChain());
						cvg.open();
					} else {
						//TODO : For Secret Key, ask password and show it
					}
				}
			}
	}
	
	class DeleteAction extends Action {
		IViewPart vp;
		public DeleteAction(IViewPart mvp) {
			setText("Delete");
			setToolTipText("Delete selected keys/certificates");
			setImageDescriptor(GUIIcons.TRASH_ICON);
			vp = mvp;
		}
		public void run() {
			ISelection selection = viewer.getSelection();
			if (selection.isEmpty())
				RCPGUI.infoMessage("Delete private key(s) and/or certificate(s)","Please select first an entry in the list.");
			else {
				String[] aliases_to_del = getSelectedAlias();
				String aliases = "alias ";
				if (aliases_to_del.length>1)
				    aliases = "aliases ";
				for (int i = 0; i < aliases_to_del.length; i++) {
                    aliases += aliases_to_del[i] + ( i != (aliases_to_del.length-1) ? ", " : "" );
                }
				if ( EParapherManager.getInstance().getUI().askUserYesNo("Please confirm the deletion of keys and/or certificates for " + aliases) ) {
					for (int i = 0; i < aliases_to_del.length; i++) {
						try {
							if (vp instanceof UserCertificateStoreView)
								EPKeystoreManager.getInstance().getUserkeystore().getKeystore().deleteEntry(aliases_to_del[i]);
							if (vp instanceof TrustedCertificateStoreView) {
								EPKeystoreManager.getInstance().getTrustStore().getKeystore().deleteEntry(aliases_to_del[i]);
							    log.info("Alias " + aliases_to_del[i] + " deleted in truststore");
							}
						} catch (KeyStoreException e) {
							log.error("Cannot delete alias " + aliases_to_del[i] + " in user keystore", e );
						}
						viewer.refresh();
					}
					if (vp instanceof UserCertificateStoreView)
						EPKeystoreManager.getInstance().getUserkeystore().saveKeyStore();
					if (vp instanceof TrustedCertificateStoreView)
						EPKeystoreManager.getInstance().getTrustStore().saveTrustStore();
				}
			}
		}
	}
}