package org.eclipse.core.internal.runtime;

/*
 * (c) Copyright IBM Corp. 2000, 2001.
 * All Rights Reserved.
 */

import org.eclipse.core.runtime.*;
import java.io.*;
import java.net.*;
import java.util.*;

/**
 * A database that remembers information, such as usernames and
 * passwords.  The information is stored in memory and can be saved
 * to disk in an encrypted format.  While the API is phrased in terms of
 * URLs, realms and authentication schemes, not all of these must have
 * significant values.  For example, if "realm" is not relevant to a
 * particular application, it can be left blank (though not
 * <code>null</code>).
 */
public class AuthorizationDatabase {
	/**
	 * A nested hashtable that stores authorization information. The
	 * table maps server URLs to realms to authentication schemes to
	 * authorization information.
	 */
	private Hashtable authorizationInfo = new Hashtable(5);

	/**
	 * A hashtable mapping resource URLs to realms.
	 */
	private Hashtable protectionSpace = new Hashtable(5);

	private File file = null;
	private String password = null;
	private boolean needsSaving = true;
/**
 * Creates a new authorization database whose data cannot be saved to
 * disk.
 */
public AuthorizationDatabase() {
}
/**
 * Creates a new authorization database, or opens an existing one, whose
 * data is, or can be, saved to a file with the given filename. A
 * password must be given to create a new database and an existing
 * database is opened by supplying the password that was given to create
 * it.
 *
 * @param filename the location of the database on disk. For example,
 *		"c:/temp/database"
 * @param password the password to access the database. For example,
 *		"secret"
 * @exception Exception if there are problems creating the database.
 *		Reasons include:
 * <ul>
 * <li>The database could not be opened because the wrong password was given.
 * <li>The database could not be opened because the specified file is corrupt.
 * </ul>
 */
public AuthorizationDatabase(String filename, String password) throws CoreException {
	Assert.isNotNull(filename);
	Assert.isNotNull(password);
	this.password = password;
	file = new File(filename);
	load();
}
/**
 * Adds the given authorization information to the database. The
 * information is relevant for the specified protection space and the
 * given authorization scheme. The protection space is defined by the
 * combination of the given server URL and realm. The authorization 
 * scheme determines what the authorization information contains and how 
 * it should be used. The authorization information is a <code>Map</code> 
 * of <code>String</code> to <code>String</code> and typically
 * contain information such as usernames and passwords.
 *
 * @param serverUrl the URL identifying the server for this authorization
 *		information. For example, "http://www.hostname.com/".
 * @param realm the subsection of the given server to which this
 *		authorization information applies.  For example,
 *		"realm1@hostname.com" or "" for no realm.
 * @param authScheme the scheme for which this authorization information
 *		applies. For example, "Basic" or "" for no authorization scheme
 * @param info a <code>Map</code> containing authorization information 
 *		such as usernames and passwords
 */
public void addAuthorizationInfo(URL serverUrl, String realm, String authScheme, Map info){
	Assert.isNotNull(serverUrl);
	Assert.isNotNull(realm);
	Assert.isNotNull(authScheme);
	Assert.isNotNull(info);

	String url = serverUrl.toString();
	Hashtable realmToAuthScheme = (Hashtable)authorizationInfo.get(url);
	if(realmToAuthScheme == null){
		realmToAuthScheme = new Hashtable(5);
		authorizationInfo.put(url, realmToAuthScheme);
	}

	Hashtable authSchemeToInfo = (Hashtable)realmToAuthScheme.get(realm);
	if(authSchemeToInfo == null){
		authSchemeToInfo = new Hashtable(5);
		realmToAuthScheme.put(realm, authSchemeToInfo);
	}

	authSchemeToInfo.put(authScheme.toLowerCase(), info);
	needsSaving = true;
}
/**
 * Adds the specified resource to the protection space specified by the
 * given realm. All resources at or deeper than the depth of the last
 * symbolic element in the path of the given resource URL are assumed to
 * be in the same protection space.
 *
 * @param resourceUrl the URL identifying the resources to be added to
 *		the specified protection space. For example,
 *		"http://www.hostname.com/folder/".
 * @param realm the name of the protection space. For example,
 *		"realm1@hostname.com"
 */
public void addProtectionSpace(URL resourceUrl, String realm){
	Assert.isNotNull(resourceUrl);
	Assert.isNotNull(realm);

	String file = resourceUrl.getFile();
	if(!file.endsWith("/")){
		resourceUrl = URLTool.getParent(resourceUrl);
	}

	String oldRealm = getProtectionSpace(resourceUrl);
	if(oldRealm != null && oldRealm.equals(realm)){
		return;
	}

	String url1 = resourceUrl.toString();
	Enumeration urls = protectionSpace.keys();
	while(urls.hasMoreElements()){
		String url2 = (String)urls.nextElement();
		if(url1.startsWith(url2) || url2.startsWith(url1)){
			protectionSpace.remove(url2);
			break;
		}
	}

	protectionSpace.put(url1, realm);
	needsSaving = true;
}
/**
 * Removes the authorization information for the specified protection
 * space and given authorization scheme. The protection space is defined
 * by the given server URL and realm.
 *
 * @param serverUrl the URL identifying the server to remove the
 *		authorization information for. For example,
 *		"http://www.hostname.com/".
 * @param realm the subsection of the given server to remove the
 *		authorization information for. For example,
 *		"realm1@hostname.com" or "" for no realm.
 * @param authScheme the scheme for which the authorization information
 *		to remove applies. For example, "Basic" or "" for no
 *		authorization scheme.
 */
public void flushAuthorizationInfo(URL serverUrl, String realm, String authScheme) {
	Hashtable realmToAuthScheme = (Hashtable)authorizationInfo.get(serverUrl.toString());

	if(realmToAuthScheme == null){
		return;
	}

	Hashtable authSchemeToInfo = (Hashtable)realmToAuthScheme.get(realm);

	if(authSchemeToInfo == null){
		return;
	}

	authSchemeToInfo.remove(authScheme.toLowerCase());

	needsSaving = true;
}
/**
 * Returns the authorization information for the specified protection
 * space and given authorization scheme. The protection space is defined
 * by the given server URL and realm. Returns <code>null</code> if no
 * such information exists.
 *
 * @param serverUrl the URL identifying the server for the authorization
 *		information. For example, "http://www.hostname.com/".
 * @param realm the subsection of the given server to which the
 *		authorization information applies.  For example,
 *		"realm1@hostname.com" or "" for no realm.
 * @param authScheme the scheme for which the authorization information
 *		applies. For example, "Basic" or "" for no authorization scheme
 * @return the authorization information for the specified protection
 *		space and given authorization scheme, or <code>null</code> if no
 *		such information exists
 */
public Map getAuthorizationInfo(URL serverUrl, String realm, String authScheme){
	Hashtable realmToAuthScheme = (Hashtable)authorizationInfo.get(serverUrl.toString());
	if(realmToAuthScheme == null){
		return null;
	}

	Hashtable authSchemeToInfo = (Hashtable)realmToAuthScheme.get(realm);
	if(authSchemeToInfo == null){
		return null;
	}

	return (Map)authSchemeToInfo.get(authScheme.toLowerCase());
}
/**
 * Returns the protection space (realm) for the specified resource, or
 * <code>null</code> if the realm is unknown.
 *
 * @param resourceUrl the URL of the resource whose protection space is
 *		returned. For example, "http://www.hostname.com/folder/".
 * @return the protection space (realm) for the specified resource, or
 *		<code>null</code> if the realm is unknown
 */
public String getProtectionSpace(URL resourceUrl){
	while(resourceUrl != null){
		String realm = (String)protectionSpace.get(resourceUrl.toString());
		if(realm != null){
			return realm;
		}
		resourceUrl = URLTool.getParent(resourceUrl);
	}

	return null;
}
private void load() throws CoreException {
	if (file == null)
		return;
	if (!file.exists()) {
		save();
		return;
	}
	try {
		InputStream input = new FileInputStream(file);
		try {
			load(input);
		} finally {
			input.close();
		}
	} catch (IOException e) {
		throw new CoreException(new Status(IStatus.ERROR,Platform.PI_RUNTIME,13,Policy.bind("meta.unableToReadAuthorization",file.toString()),e));
	} catch (ClassNotFoundException e) {
		throw new CoreException(new Status(IStatus.ERROR,Platform.PI_RUNTIME,13,Policy.bind("meta.unableToReadAuthorization",file.toString()),e));
	}
}
private void load(InputStream is) throws IOException, ClassNotFoundException {
	CipherInputStream cis = new CipherInputStream(is, password);
	ObjectInputStream ois = new ObjectInputStream(cis);
	authorizationInfo = (Hashtable) ois.readObject();
	protectionSpace = (Hashtable) ois.readObject();
	ois.close();
}
/**
 * Saves the authorization database to disk.
 */
public void save() throws CoreException {
	if (!needsSaving || file == null)
		return;
	try {
		file.delete();
		file.createNewFile();
		save(new FileOutputStream(file));
	} catch (IOException e) {
		throw new CoreException(new Status(IStatus.ERROR,Platform.PI_RUNTIME,13,Policy.bind("meta.unableToWriteAuthorization",file.toString()),e));
	}
	needsSaving = false;
}
private void save(OutputStream os) throws IOException {
	CipherOutputStream cos = new CipherOutputStream(os, password);
	ObjectOutputStream oos = new ObjectOutputStream(cos);
	oos.writeObject(authorizationInfo);
	oos.writeObject(protectionSpace);
	oos.close();
}
/**
 * Sets the password to use for accessing this database.  If the database
 * is subsequently saved, this new password is used.
 */
public boolean setPassword(String oldValue, String newValue) {
	if (!oldValue.equals(password))
		return false;
	password = newValue;
	needsSaving = true;
	return true;
}
}