/*******************************************************************************
 * Copyright (c) 2007, 2008 IBM Corporation and others. All rights reserved.
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
 * and is available at http://www.eclipse.org/legal/epl-v10.html
 * 
 * Contributors: IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.equinox.internal.simpleconfigurator;

import java.io.*;
import java.net.URL;
import java.util.*;
import org.eclipse.equinox.internal.simpleconfigurator.utils.*;
import org.osgi.framework.*;
import org.osgi.service.packageadmin.PackageAdmin;
import org.osgi.service.startlevel.StartLevel;

class ConfigApplier {
	private static final String LAST_BUNDLES_TXT = "last.bundles.info"; //$NON-NLS-1$

	private BundleContext manipulatingContext;
	private PackageAdmin adminService = null;
	private StartLevel startLevelService = null;
	private final boolean runningOnEquinox;
	private boolean checkManifestBeforeInstall = false;

	private Bundle callingBundle;

	ConfigApplier(BundleContext context, Bundle callingBundle) {
		this.manipulatingContext = context;
		this.callingBundle = callingBundle;
		//String vendor = context.getProperty(Constants.FRAMEWORK_VENDOR);
		//System.out.println("vendor=" + vendor);
		this.runningOnEquinox = "Eclipse".equals(context.getProperty(Constants.FRAMEWORK_VENDOR)); //$NON-NLS-1$
		ServiceReference packageAdminRef = manipulatingContext.getServiceReference(PackageAdmin.class.getName());
		if (packageAdminRef == null)
			throw new IllegalStateException("No PackageAdmin service is available."); //$NON-NLS-1$

		adminService = (PackageAdmin) manipulatingContext.getService(packageAdminRef);

		ServiceReference startLevelRef = manipulatingContext.getServiceReference(StartLevel.class.getName());
		if (startLevelRef == null)
			throw new IllegalStateException("No StartLevelService service is available."); //$NON-NLS-1$
		startLevelService = (StartLevel) manipulatingContext.getService(startLevelRef);

	}

	void install(BundleInfo[] expectedState, URL url, boolean exclusiveMode) {
		HashSet toUninstall = null;
		if (!exclusiveMode) {
			BundleInfo[] lastInstalledBundles = getLastState();
			if (lastInstalledBundles != null) {
				toUninstall = new HashSet(Arrays.asList(lastInstalledBundles));
				toUninstall.removeAll(Arrays.asList(expectedState));
			}
			saveStateAsLast(url);
		}

		Collection prevouslyResolved = getResolvedBundles();
		Collection toRefresh = new ArrayList();
		Collection toStart = new ArrayList();
		if (exclusiveMode) {
			toRefresh.addAll(installBundles(expectedState, toStart));
			toRefresh.addAll(uninstallBundles(expectedState, adminService));
		} else {
			toRefresh.addAll(installBundles(expectedState, toStart));
			if (toUninstall != null)
				toRefresh.addAll(uninstallBundles(toUninstall));
		}
		refreshPackages((Bundle[]) toRefresh.toArray(new Bundle[toRefresh.size()]), manipulatingContext);
		if (toRefresh.size() > 0)
			try {
				manipulatingContext.getBundle().loadClass("org.eclipse.osgi.service.resolver.PlatformAdmin"); //$NON-NLS-1$
				// now see if there are any currently resolved bundles with option imports which could be resolved or
				// if there are fragments with additional constraints which conflict with an already resolved host
				Bundle[] additionalRefresh = StateResolverUtils.getAdditionalRefresh(prevouslyResolved, manipulatingContext);
				if (additionalRefresh.length > 0)
					refreshPackages(additionalRefresh, manipulatingContext);
			} catch (ClassNotFoundException cnfe) {
				// do nothing; no resolver package available
			}
		startBundles((Bundle[]) toStart.toArray(new Bundle[toStart.size()]));
		//if time stamps are the same
		//  do nothing
		//  return
		//if list exists
		//  force the list in the fwk
		//else
		//  discover bundles in folders and force the list in the fwk
	}

	private Collection getResolvedBundles() {
		Collection resolved = new HashSet();
		Bundle[] allBundles = manipulatingContext.getBundles();
		for (int i = 0; i < allBundles.length; i++)
			if ((allBundles[i].getState() & (Bundle.INSTALLED | Bundle.UNINSTALLED)) == 0)
				resolved.add(allBundles[i]);
		return resolved;
	}

	private Collection uninstallBundles(HashSet toUninstall) {
		Collection removedBundles = new ArrayList(toUninstall.size());
		for (Iterator iterator = toUninstall.iterator(); iterator.hasNext();) {
			BundleInfo current = (BundleInfo) iterator.next();
			Bundle[] matchingBundles = adminService.getBundles(current.getSymbolicName(), getVersionRange(current.getVersion()));
			for (int j = 0; matchingBundles != null && j < matchingBundles.length; j++) {
				try {
					removedBundles.add(matchingBundles[j]);
					matchingBundles[j].uninstall();
				} catch (BundleException e) {
					//TODO log in debug mode...
				}
			}
		}
		return removedBundles;
	}

	private void saveStateAsLast(URL url) {
		InputStream sourceStream = null;
		OutputStream destinationStream = null;

		File lastBundlesTxt = getLastBundleTxt();
		try {
			try {
				destinationStream = new FileOutputStream(lastBundlesTxt);
				sourceStream = url.openStream();
				SimpleConfiguratorUtils.transferStreams(sourceStream, destinationStream);
			} finally {
				if (destinationStream != null)
					destinationStream.close();
				if (sourceStream != null)
					sourceStream.close();
			}
		} catch (IOException e) {
			//nothing
		}
	}

	private File getLastBundleTxt() {
		return manipulatingContext.getDataFile(LAST_BUNDLES_TXT);
	}

	private BundleInfo[] getLastState() {
		File lastBundlesTxt = getLastBundleTxt();
		if (!lastBundlesTxt.isFile())
			return null;
		try {
			return (BundleInfo[]) SimpleConfiguratorUtils.readConfiguration(lastBundlesTxt.toURL()).toArray(new BundleInfo[1]);
		} catch (IOException e) {
			return null;
		}
	}

	private ArrayList installBundles(BundleInfo[] finalList, Collection toStart) {
		ArrayList installed = new ArrayList();
		//printSystemBundle();

		boolean useReference = true;
		if (manipulatingContext.getProperty(SimpleConfiguratorConstants.PROP_KEY_USE_REFERENCE) == null)
			useReference = true;
		else
			useReference = Boolean.valueOf(manipulatingContext.getProperty(SimpleConfiguratorConstants.PROP_KEY_USE_REFERENCE)).booleanValue();

		for (int i = 0; i < finalList.length; i++) {
			if (finalList[i] == null)
				continue;
			//TODO here we do not deal with bundles that don't have a symbolic id
			//TODO Need to handle the case where getBundles return multiple value

			String symbolicName = finalList[i].getSymbolicName();
			String version = finalList[i].getVersion();

			if (checkManifestBeforeInstall) {
				Dictionary manifest = Utils.getOSGiManifest(finalList[i].getLocation());
				if (manifest == null) {
					Utils.log(1, null, null, "No bundle found at: " + finalList[i].getLocation(), null); //$NON-NLS-1$
					finalList[i] = null;
					continue;
				}

				//if (manifest != null)
				try {
					symbolicName = (String) manifest.get(Constants.BUNDLE_SYMBOLICNAME);
				} catch (RuntimeException re) {
					System.err.println("cannot get Manifest :" + finalList[i]); //$NON-NLS-1$
					throw re;
				}
				if (symbolicName != null && symbolicName.indexOf(';') != -1)
					symbolicName = symbolicName.substring(0, symbolicName.indexOf(';')).trim();

				version = (String) manifest.get(Constants.BUNDLE_VERSION);
			}

			Bundle[] matches = null;
			if (symbolicName != null && version != null)
				matches = adminService.getBundles(symbolicName, getVersionRange(version));

			Bundle current = matches == null ? null : (matches.length == 0 ? null : matches[0]);
			if (current == null) {
				try {
					String location = finalList[i].getLocation();
					if (location == null)
						continue;
					if (runningOnEquinox && useReference && location.startsWith("file:")) //$NON-NLS-1$
						location = "reference:" + location; //$NON-NLS-1$

					//TODO Need to eliminate System Bundle.
					// If a system bundle doesn't have a SymbolicName header, like Knopflerfish 4.0.0,
					// it will be installed unfortunately. 
					current = manipulatingContext.installBundle(location);
					if (Activator.DEBUG)
						System.out.println("installed bundle:" + finalList[i]); //$NON-NLS-1$
					installed.add(current);
				} catch (BundleException e) {
					if (Activator.DEBUG) {
						System.err.println("Can't install " + symbolicName + '/' + version + " from location " + finalList[i].getLocation()); //$NON-NLS-1$ //$NON-NLS-2$
						e.printStackTrace();
					}
					continue;
				}
			}
			int startLevel = finalList[i].getStartLevel();
			if (startLevel != BundleInfo.NO_LEVEL)
				if (current.getBundleId() != 0) {
					String name = current.getSymbolicName();
					try {
						if (startLevel > 0)
							if (!SimpleConfiguratorConstants.TARGET_CONFIGURATOR_NAME.equals(name))
								startLevelService.setBundleStartLevel(current, startLevel);
					} catch (IllegalArgumentException ex) {
						Utils.log(4, null, null, "Failed to set start level of Bundle:" + finalList[i], ex); //$NON-NLS-1$
					}
				}
			if (finalList[i].isMarkedAsStarted()) {
				toStart.add(current);
			}
		}
		return installed;
	}

	private void refreshPackages(Bundle[] bundles, BundleContext context) {
		if (bundles.length == 0)
			return;
		ServiceReference packageAdminRef = context.getServiceReference(PackageAdmin.class.getName());
		PackageAdmin packageAdmin = null;
		if (packageAdminRef != null) {
			packageAdmin = (PackageAdmin) context.getService(packageAdminRef);
			if (packageAdmin == null)
				return;
		}
		final boolean[] flag = new boolean[] {false};
		FrameworkListener listener = new FrameworkListener() {
			public void frameworkEvent(FrameworkEvent event) {
				if (event.getType() == FrameworkEvent.PACKAGES_REFRESHED) {
					synchronized (flag) {
						flag[0] = true;
						flag.notifyAll();
					}
				}
			}
		};
		context.addFrameworkListener(listener);
		packageAdmin.refreshPackages(bundles);
		synchronized (flag) {
			while (!flag[0]) {
				try {
					flag.wait();
				} catch (InterruptedException e) {
					//ignore
				}
			}
		}
		//		if (DEBUG) {
		//			for (int i = 0; i < bundles.length; i++) {
		//				System.out.println(SimpleConfiguratorUtils.getBundleStateString(bundles[i]));
		//			}
		//		}
		context.removeFrameworkListener(listener);
		context.ungetService(packageAdminRef);
	}

	private void startBundles(Bundle[] bundles) {
		for (int i = 0; i < bundles.length; i++) {
			Bundle bundle = bundles[i];
			if (bundle.getState() == Bundle.STARTING && (bundle == callingBundle || bundle == manipulatingContext.getBundle()))
				continue;

			try {
				bundle.start();
				if (Activator.DEBUG)
					System.out.println("started Bundle:" + bundle.getSymbolicName() + '(' + bundle.getLocation() + ':' + bundle.getBundleId() + ')'); //$NON-NLS-1$
			} catch (BundleException e) {
				e.printStackTrace();
				//				FrameworkLogEntry entry = new FrameworkLogEntry(FrameworkAdaptor.FRAMEWORK_SYMBOLICNAME, NLS.bind(EclipseAdaptorMsg.ECLIPSE_STARTUP_FAILED_START, bundle.getLocation()), 0, e, null);
				//				log.log(entry);
			}
		}
	}

	/**
	 * Uninstall bundles which are not listed on finalList.  
	 * 
	 * @param finalList bundles list not to be uninstalled.
	 * @param packageAdmin package admin service.
	 * @return Collection HashSet of bundles finally installed.
	 */
	private Collection uninstallBundles(BundleInfo[] finalList, PackageAdmin packageAdmin) {
		Bundle[] allBundles = manipulatingContext.getBundles();

		//Build a set with all the bundles from the system
		Set removedBundles = new HashSet(allBundles.length);
		//		configurator.setPrerequisiteBundles(allBundles);
		for (int i = 0; i < allBundles.length; i++) {
			if (allBundles[i].getBundleId() == 0)
				continue;
			removedBundles.add(allBundles[i]);
		}

		//Remove all the bundles appearing in the final list from the set of installed bundles
		for (int i = 0; i < finalList.length; i++) {
			if (finalList[i] == null)
				continue;
			Bundle[] toAdd = packageAdmin.getBundles(finalList[i].getSymbolicName(), getVersionRange(finalList[i].getVersion()));
			for (int j = 0; toAdd != null && j < toAdd.length; j++) {
				removedBundles.remove(toAdd[j]);
			}
		}

		for (Iterator iter = removedBundles.iterator(); iter.hasNext();) {
			try {
				Bundle bundle = ((Bundle) iter.next());
				bundle.uninstall();
				if (Activator.DEBUG)
					System.out.println("uninstalled Bundle:" + bundle.getSymbolicName() + '(' + bundle.getLocation() + ':' + bundle.getBundleId() + ')'); //$NON-NLS-1$
			} catch (BundleException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}

		return removedBundles;
	}

	private String getVersionRange(String version) {
		return version == null ? null : new StringBuffer().append('[').append(version).append(',').append(version).append(']').toString();
	}
}