package org.eclipse.team.internal.ccvs.core;

/*
 * (c) Copyright IBM Corp. 2000, 2002.
 * All Rights Reserved.
 */
 
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Set;

import org.eclipse.core.resources.IContainer;
import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.IWorkspaceRunnable;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Path;
import org.eclipse.core.runtime.Status;
import org.eclipse.team.core.RepositoryProvider;
import org.eclipse.team.core.Team;
import org.eclipse.team.core.TeamException;
import org.eclipse.team.internal.ccvs.core.client.Checkout;
import org.eclipse.team.internal.ccvs.core.client.Command;
import org.eclipse.team.internal.ccvs.core.client.Import;
import org.eclipse.team.internal.ccvs.core.client.Request;
import org.eclipse.team.internal.ccvs.core.client.Session;
import org.eclipse.team.internal.ccvs.core.client.Update;
import org.eclipse.team.internal.ccvs.core.client.Command.GlobalOption;
import org.eclipse.team.internal.ccvs.core.client.Command.LocalOption;
import org.eclipse.team.internal.ccvs.core.client.Command.QuietOption;
import org.eclipse.team.internal.ccvs.core.connection.CVSRepositoryLocation;
import org.eclipse.team.internal.ccvs.core.connection.CVSServerException;
import org.eclipse.team.internal.ccvs.core.resources.CVSWorkspaceRoot;
import org.eclipse.team.internal.ccvs.core.resources.RemoteFolder;
import org.eclipse.team.internal.ccvs.core.resources.RemoteFolderTree;
import org.eclipse.team.internal.ccvs.core.resources.RemoteModule;
import org.eclipse.team.internal.ccvs.core.syncinfo.FolderSyncInfo;
import org.eclipse.team.internal.ccvs.core.util.Util;

public class CVSProvider implements ICVSProvider {

	private static final String STATE_FILE = ".cvsProviderState"; //$NON-NLS-1$
	
	private static CVSProvider instance;
	private Map repositories;
	
	private List listeners = new ArrayList();
		
	private CVSProvider() {
		repositories = new HashMap();
	}
	
	/*
	 * Add the repository location to the cahced locations
	 */
	private void addToCache(ICVSRepositoryLocation repository) {
		repositories.put(repository.getLocation(), repository);
	}
	
	private void repositoryAdded(ICVSRepositoryLocation repository) {
		Iterator it = listeners.iterator();
		while (it.hasNext()) {
			ICVSListener listener = (ICVSListener)it.next();
			listener.repositoryAdded(repository);
		}
	}
	
	public void addRepositoryListener(ICVSListener listener) {
		listeners.add(listener);
	}
	
	public void removeRepositoryListener(ICVSListener listener) {
		listeners.remove(listener);
	}
	
	/**
	 * @see ICVSProvider#checkout(ICVSRepositoryLocation, IProject, String, String, IProgressMonitor)
	 */
	public void checkout(
		ICVSRepositoryLocation repository,
		IProject project,
		String sourceModule,
		CVSTag tag,
		IProgressMonitor monitor)
		throws TeamException {
		
		if (sourceModule == null)
			sourceModule = project.getName();
		checkout(new ICVSRemoteFolder[] { new RemoteFolder(null, repository, new Path(sourceModule), tag)},
			new IProject[] { project }, monitor);
	}

	/*
	 * Delete the target projects before checking out
	 */
	private void scrubProjects(IProject[] projects, IProgressMonitor monitor) throws CVSException {
		if (projects == null) {
			monitor.done();
			return;
		}
		monitor.beginTask(Policy.bind("CVSProvider.Scrubbing_projects_1"), projects.length * 100); //$NON-NLS-1$
		try {	
			for (int i=0;i<projects.length;i++) {
				IProject project = projects[i];
				if (project != null && project.exists()) {
					if(!project.isOpen()) {
						project.open(Policy.subMonitorFor(monitor, 10));
					}
					// XXX: temporary code to support creating a java project for sources in CVS
					// should be removed once nature support is added to the UI.
					// delete children, keep project 
					monitor.subTask(Policy.bind("CVSProvider.Scrubbing_local_project_1")); //$NON-NLS-1$
					IResource[] children = project.members(IContainer.INCLUDE_TEAM_PRIVATE_MEMBERS);
					IProgressMonitor subMonitor = Policy.subMonitorFor(monitor, 80);
					subMonitor.beginTask(null, children.length * 100);
					try {
						for (int j = 0; j < children.length; j++) {
							if ( ! children[j].getName().equals(".project")) {//$NON-NLS-1$
								children[j].delete(true /*force*/, Policy.subMonitorFor(subMonitor, 100));
							}
						}
					} finally {
						subMonitor.done();
					}
					CVSWorkspaceRoot.getCVSFolderFor(project).unmanage(Policy.subMonitorFor(monitor, 10));
				} else if (project != null) {
					// Make sure there is no directory in the local file system.
					File location = new File(project.getParent().getLocation().toFile(), project.getName());
					if (location.exists()) {
						deepDelete(location);
					}
				}
			}
		} catch (CoreException e) {
			throw wrapException(e);
		} finally {
			monitor.done();
		}
	}
	
	private void deepDelete(File resource) {
		if (resource.isDirectory()) {
			File[] fileList = resource.listFiles();
			for (int i = 0; i < fileList.length; i++) {
				deepDelete(fileList[i]);
			}
		}
		resource.delete();
	}
	
	/*
	 * Bring the provied projects into the workspace
	 */
	private void refreshProjects(IProject[] projects, IProgressMonitor monitor) throws CoreException, TeamException {
		monitor.beginTask(Policy.bind("CVSProvider.Creating_projects_2"), projects.length * 100); //$NON-NLS-1$
		try {
			for (int i = 0; i < projects.length; i++) {
				IProject project = projects[i];
				// Register the project with Team
				// (unless the project already has the proper nature from the project meta-information)
				if (!project.getDescription().hasNature(CVSProviderPlugin.getTypeId())) {
					Team.addNatureToProject(project, CVSProviderPlugin.getTypeId(), Policy.subMonitorFor(monitor, 100));
				}
			}
			
		} finally {
			monitor.done();
		}
	}
	
	
	/**
	 * @see ICVSProvider#checkout(ICVSRemoteResource[], IProject[], IProgressMonitor)
	 */
	public void checkout(final ICVSRemoteFolder[] resources, final IProject[] projects, final IProgressMonitor monitor) throws TeamException {
		final TeamException[] eHolder = new TeamException[1];
		try {
			IWorkspaceRunnable workspaceRunnable = new IWorkspaceRunnable() {
				public void run(IProgressMonitor pm) throws CoreException {
					try {
						pm.beginTask(null, 1000 * resources.length);
						
						// Get the location of the workspace root
						ICVSFolder root = CVSWorkspaceRoot.getCVSFolderFor(ResourcesPlugin.getWorkspace().getRoot());
						
						for (int i=0;i<resources.length;i++) {
							IProject project = null;
							RemoteFolder resource = (RemoteFolder)resources[i];
							
							// Determine the provided target project if there is one
							if (projects != null) 
								project = projects[i];
							
							// Determine the remote module to be checked out
							String moduleName;
							if (resource instanceof RemoteModule) {
								moduleName = ((RemoteModule)resource).getName();
							} else {
								moduleName = resource.getRepositoryRelativePath();
							}
							
							// Open a connection session to the repository
							ICVSRepositoryLocation repository = resource.getRepository();
							Session session = new Session(repository, root);
							try {
								session.open(Policy.subMonitorFor(pm, 50));
								
								// Determine the local target projects (either the project provider or the module expansions) 
								final Set targetProjects = new HashSet();
								if (project == null) {
									
									// Fetch the module expansions
									IStatus status = Request.EXPAND_MODULES.execute(session, new String[] {moduleName}, Policy.subMonitorFor(pm, 50));
									if (status.getCode() == CVSStatus.SERVER_ERROR) {
										// XXX Should we cleanup any partially checked out projects?
										throw new CVSServerException(status);
									}
									
									// Convert the module expansions to local projects
									String[] expansions = session.getModuleExpansions();
									for (int j = 0; j < expansions.length; j++) {
										targetProjects.add(ResourcesPlugin.getWorkspace().getRoot().getProject(new Path(expansions[j]).segment(0)));
									}
									
								} else {
									targetProjects.add(project);
								}
								
								// Prepare the target projects to receive resources
								root.run(new ICVSRunnable() {
									public void run(IProgressMonitor monitor) throws CVSException {
										scrubProjects((IProject[]) targetProjects.toArray(new IProject[targetProjects.size()]), monitor);
									}
								}, Policy.subMonitorFor(pm, 100));
							
								// Build the local options
								List localOptions = new ArrayList();
								// Add the option to load into the target project if one was supplied
								if (project != null) {
									localOptions.add(Checkout.makeDirectoryNameOption(project.getName()));
								}
								// Prune empty directories if pruning enabled
								if (CVSProviderPlugin.getPlugin().getPruneEmptyDirectories()) 
									localOptions.add(Checkout.PRUNE_EMPTY_DIRECTORIES);
								// Add the options related to the CVSTag
								CVSTag tag = resource.getTag();
								if (tag == null) {
									// A null tag in a remote resource indicates HEAD
									tag = CVSTag.DEFAULT;
								}
								localOptions.add(Update.makeTagOption(tag));
		
								// Perform the checkout
								IStatus status = Command.CHECKOUT.execute(session,
									getDefaultGlobalOptions(),
									(LocalOption[])localOptions.toArray(new LocalOption[localOptions.size()]),
									new String[]{moduleName},
									null,
									Policy.subMonitorFor(pm, 800));
								if (status.getCode() == CVSStatus.SERVER_ERROR) {
									// XXX Should we cleanup any partially checked out projects?
									throw new CVSServerException(status);
								}
								
								// Bring the project into the workspace
								refreshProjects((IProject[])targetProjects.toArray(new IProject[targetProjects.size()]), Policy.subMonitorFor(pm, 100));

							} finally {
								session.close();
							}
						}
					}
					catch (TeamException e) {
						// Pass it outside the workspace runnable
						eHolder[0] = e;
					} finally {
						pm.done();
					}
					// CoreException and OperationCanceledException are propagated
				}
			};
			ResourcesPlugin.getWorkspace().run(workspaceRunnable, monitor);
		} catch (CoreException e) {
			throw wrapException(e);
		} finally {
			monitor.done();
		}		
		// Re-throw the TeamException, if one occurred
		if (eHolder[0] != null) {
			throw eHolder[0];
		}
	}

	/**
	 * @see ICVSProvider#createRepository(Properties)
	 */
	public ICVSRepositoryLocation createRepository(Properties configuration) throws CVSException {
		// Create a new repository location
		CVSRepositoryLocation location = CVSRepositoryLocation.fromProperties(configuration);
		
		// Check the cache for an equivalent instance and if there is one, throw an exception
		CVSRepositoryLocation existingLocation = (CVSRepositoryLocation)repositories.get(location.getLocation());
		if (existingLocation != null) {
			throw new CVSException(new CVSStatus(CVSStatus.ERROR, Policy.bind("CVSProvider.alreadyExists"))); //$NON-NLS-1$
		}

		return location;
	}

	/**
	 * @see ICVSProvider#addRepository(ICVSRepositoryLocation)
	 */
	public void addRepository(ICVSRepositoryLocation repository) throws CVSException {
		// Check the cache for an equivalent instance and if there is one, just update the cache
		CVSRepositoryLocation existingLocation = (CVSRepositoryLocation)repositories.get(repository.getLocation());
		if (existingLocation != null) {
			((CVSRepositoryLocation)repository).updateCache();
		} else {
			// Cache the password and register the repository location
			addToCache(repository);
			((CVSRepositoryLocation)repository).updateCache();
			repositoryAdded(repository);
		}
	}
	
	/**
	 * @see ICVSProvider#disposeRepository(ICVSRepositoryLocation)
	 */
	public void disposeRepository(ICVSRepositoryLocation repository) throws CVSException {
		((CVSRepositoryLocation)repository).dispose();
		removeFromCache(repository);
	}

	public boolean isKnownRepository(String location) {
		return repositories.get(location) != null;
	}
	
	public static GlobalOption[] getDefaultGlobalOptions() {
		QuietOption option = CVSProviderPlugin.getPlugin().getQuietness();
		if (option == null)
			return Command.NO_GLOBAL_OPTIONS;
		else
			return new GlobalOption[] {option};
	}
	
	/**
	 * Return the singleton instance of CVSProvider
	 */
	public static CVSProvider getInstance() {
		return instance;
	}
	
	public String[] getExpansions(ICVSRemoteFolder[] resources, IProgressMonitor monitor) throws CVSException {
		
		if (resources.length == 0) return new String[0];
		
		// Get the location of the workspace root
		ICVSFolder root = CVSWorkspaceRoot.getCVSFolderFor(ResourcesPlugin.getWorkspace().getRoot());
		
		// Get the command arguments
		String[] arguments = new String[resources.length];
		for (int i = 0; i < resources.length; i++) {
			if (resources[i] instanceof RemoteModule) {
				arguments[i] = ((RemoteModule)resources[i]).getName();
			} else {
				arguments[i]  = resources[i].getRepositoryRelativePath();
			}
		}
		
		// Perform the Expand-Modules command
		IStatus status;
		Session s = new Session(resources[0].getRepository(), root);
		s.open(monitor);
		try {
			status = Request.EXPAND_MODULES.execute(s, arguments, monitor);
		} finally {
			s.close();
		}
		if (status.getCode() == CVSStatus.SERVER_ERROR) {
			throw new CVSServerException(status);
		}
		
		return s.getModuleExpansions();
	}
	
	/**
	 * @see ICVSProvider#getKnownRepositories()
	 */
	public ICVSRepositoryLocation[] getKnownRepositories() {
		return (ICVSRepositoryLocation[])repositories.values().toArray(new ICVSRepositoryLocation[repositories.size()]);
	}


	/**
	 * @see ICVSProvider#getRepository(String)
	 */
	public ICVSRepositoryLocation getRepository(String location) throws CVSException {
		ICVSRepositoryLocation repository = (ICVSRepositoryLocation)repositories.get(location);
		if (repository == null) {
			repository = CVSRepositoryLocation.fromString(location);
			addToCache(repository);
			repositoryAdded(repository);
		}
		return repository;
	}
	
	/**
	 * @see ICVSProvider#getSupportedConnectionMethods()
	 */
	public String[] getSupportedConnectionMethods() {
		IConnectionMethod[] methods = CVSRepositoryLocation.getPluggedInConnectionMethods();
		String[] result = new String[methods.length];
		for (int i=0;i<methods.length;i++)
			result[i] = methods[i].getName();
		return result;
	}

	/**
	 * @see ICVSProvider#createModule()
	 */
	public void createModule(ICVSRepositoryLocation location, IProject project, String moduleName, IProgressMonitor monitor) throws TeamException {
		
		// Determine if the repository is known
		boolean alreadyExists = isCached(location);
		// Set the folder sync info of the project to point to the remote module
		ICVSFolder folder = (ICVSFolder)CVSWorkspaceRoot.getCVSResourceFor(project);
			
		try {
			// Get the import properties
			String message = Policy.bind("CVSProvider.initialImport"); //$NON-NLS-1$
			String vendor = location.getUsername();
			String tag = "start"; //$NON-NLS-1$
			String projectName = project.getName();
			if (moduleName == null)
				moduleName = projectName;

			// Perform the import using a dummy root so the local project is not traversed
			Session s = new Session(location, new RemoteFolderTree(null, location, Path.EMPTY, null));
			s.open(monitor);
			try {
				IStatus status = Command.IMPORT.execute(s,
					getDefaultGlobalOptions(),
					new LocalOption[] {Import.makeArgumentOption(Command.MESSAGE_OPTION, message)},
					new String[] { moduleName, vendor, tag },
					null,
					monitor);
				// If we get a warning, the operation most likely failed so check that the status is OK
				if (status.getCode() == CVSStatus.SERVER_ERROR  || ! status.isOK()) {
					throw new CVSServerException(status);
				}
			} finally {
				s.close();
			}
						
			folder.setFolderSyncInfo(new FolderSyncInfo(moduleName, location.getLocation(), null, false));

			// Register the project with Team
			// (unless the project already has the proper nature from the project meta-information)
			try {
				if (!project.getDescription().hasNature(CVSProviderPlugin.getTypeId())) {
					Team.addNatureToProject(project, CVSProviderPlugin.getTypeId(), Policy.subMonitorFor(monitor, 1));
				}
			} catch (CoreException e) {
				throw wrapException(e);
			} 
		} catch (TeamException e) {
			// The checkout may have triggered password caching
			// Therefore, if this is a newly created location, we want to clear its cache
			if ( ! alreadyExists)
				disposeRepository(location);
			throw e;
		}
		// Add the repository if it didn't exist already
		if ( ! alreadyExists)
			addRepository(location);
	}
		
	private CVSTag getTagFromProperties(Properties configuration) {
		String date = configuration.getProperty("date"); //$NON-NLS-1$
		String tagName = configuration.getProperty("tag"); //$NON-NLS-1$
		if (tagName == null)
			tagName = configuration.getProperty("branch"); //$NON-NLS-1$
		if (tagName == null)
			return CVSTag.DEFAULT;
		return new CVSTag(tagName, CVSTag.BRANCH);
	}
	
	private boolean isCached(ICVSRepositoryLocation repository) {
		return repositories.containsKey(repository.getLocation());
	}
	
	public static boolean isText(IFile file) {
		return Team.getType(file) == Team.TEXT;
	}
	
	private void removeFromCache(ICVSRepositoryLocation repository) {
		if (repositories.remove(repository.getLocation()) != null) {
			Iterator it = listeners.iterator();
			while (it.hasNext()) {
				ICVSListener listener = (ICVSListener)it.next();
				listener.repositoryRemoved(repository);
			}
		}
	}
	
	public void setSharing(IProject project, FolderSyncInfo info, IProgressMonitor monitor) throws TeamException {
		
		// Ensure provided info matches that of the project
		ICVSFolder folder = (ICVSFolder)CVSWorkspaceRoot.getCVSResourceFor(project);
		FolderSyncInfo folderInfo = folder.getFolderSyncInfo();
		if ( ! info.equals(folderInfo)) {
			throw new CVSException(new CVSStatus(CVSStatus.ERROR, Policy.bind("CVSProvider.infoMismatch", project.getName())));//$NON-NLS-1$
		}
		
		// Ensure that the provided location is managed
		ICVSRepositoryLocation location = getRepository(info.getRoot());
		if (! isCached(location)) {
			addToCache(location);
			repositoryAdded(location);
		}
		
		// Register the project with Team
		// (unless the project already has the proper nature from the project meta-information)
		try {
			if (!project.getDescription().hasNature(CVSProviderPlugin.getTypeId()))
				Team.addNatureToProject(project, CVSProviderPlugin.getTypeId(), monitor);
		} catch (CoreException e) {
			throw wrapException(e);
		}
	}
	
	private CVSException wrapException(CoreException e) {
		return new CVSException(e.getStatus()); //$NON-NLS-1$
	}

	public static void startup() {
		if (instance == null) {
			instance = new CVSProvider();
		}
		try {
			getInstance().loadState();
		} catch (TeamException e) {
			Util.logError(Policy.bind("CVSProvider.errorSaving"), e);//$NON-NLS-1$
		}
	}
	
	public static void shutdown() {
		try {
			getInstance().saveState();
		} catch (TeamException e) {
			Util.logError(Policy.bind("CVSProvider.errorLoading"), e);//$NON-NLS-1$
		}
	}
	
	private void loadState() throws TeamException {
		IPath pluginStateLocation = CVSProviderPlugin.getPlugin().getStateLocation().append(STATE_FILE);
		File file = pluginStateLocation.toFile();
		if (file.exists()) {
			try {
				DataInputStream dis = new DataInputStream(new FileInputStream(file));
				readState(dis);
				dis.close();
			} catch (IOException e) {
				throw new TeamException(new Status(Status.ERROR, CVSProviderPlugin.ID, TeamException.UNABLE, Policy.bind("CVSProvider.ioException"), e));  //$NON-NLS-1$
			}
		}  else {
			// If the file did not exist, then prime the list of repositories with
			// the providers with which the projects in the workspace are shared.
			IProject[] projects = ResourcesPlugin.getWorkspace().getRoot().getProjects();
			for (int i = 0; i < projects.length; i++) {
				RepositoryProvider provider = RepositoryProvider.getProvider(projects[i], CVSProviderPlugin.getTypeId());
				if (provider!=null) {
					ICVSFolder folder = (ICVSFolder)CVSWorkspaceRoot.getCVSResourceFor(projects[i]);
					FolderSyncInfo info = folder.getFolderSyncInfo();
					if (info != null) {
						ICVSRepositoryLocation result = getRepository(info.getRoot());
						addToCache(result);
						repositoryAdded(result);
					}
				}
			}
		}
	}
	
	private void saveState() throws TeamException {
		IPath pluginStateLocation = CVSProviderPlugin.getPlugin().getStateLocation();
		File tempFile = pluginStateLocation.append(STATE_FILE + ".tmp").toFile(); //$NON-NLS-1$
		File stateFile = pluginStateLocation.append(STATE_FILE).toFile();
		try {
			DataOutputStream dos = new DataOutputStream(new FileOutputStream(tempFile));
			writeState(dos);
			dos.close();
			if (stateFile.exists()) {
				stateFile.delete();
			}
			boolean renamed = tempFile.renameTo(stateFile);
			if (!renamed) {
				throw new TeamException(new Status(Status.ERROR, CVSProviderPlugin.ID, TeamException.UNABLE, Policy.bind("CVSProvider.rename", tempFile.getAbsolutePath()), null)); //$NON-NLS-1$
			}
		} catch (IOException e) {
			throw new TeamException(new Status(Status.ERROR, CVSProviderPlugin.ID, TeamException.UNABLE, Policy.bind("CVSProvider.save",stateFile.getAbsolutePath()), e)); //$NON-NLS-1$
		}
	}
	private void readState(DataInputStream dis) throws IOException, CVSException {
		int count = dis.readInt();
		for (int i = 0; i < count; i++) {
			getRepository(dis.readUTF());
		}
	}
	
	private void writeState(DataOutputStream dos) throws IOException {
		// Write the repositories
		Collection repos = repositories.values();
		dos.writeInt(repos.size());
		Iterator it = repos.iterator();
		while (it.hasNext()) {
			ICVSRepositoryLocation root = (ICVSRepositoryLocation)it.next();
			dos.writeUTF(root.getLocation());
		}
	}
}