// License: GPL. For details, see LICENSE file.
package org.openstreetmap.josm.gui;
import static org.openstreetmap.josm.tools.I18n.tr;
import java.text.MessageFormat;
import org.openstreetmap.josm.Main;
import org.openstreetmap.josm.data.Preferences.PreferenceChangeEvent;
import org.openstreetmap.josm.data.Preferences.PreferenceChangedListener;
import org.openstreetmap.josm.data.osm.UserInfo;
import org.openstreetmap.josm.tools.CheckParameterUtil;
/**
* JosmUserStateManager is a global object which keeps track of what JOSM knows about
* the identity of the current user.
*
* JOSM can be operated anonymously provided the current user never invokes an operation
* on the OSM server which required authentication. In this case JOSM neither knows
* the user name of the OSM account of the current user nor its unique id. Perhaps the
* user doesn't have one.
*
* If the current user supplies a user name and a password in the JOSM preferences JOSM
* can partially identify the user.
*
* The current user is fully identified if JOSM knows both the user name and the unique
* id of the users OSM account. The later is retrieved from the OSM server with a
* <tt>GET /api/0.6/user/details</tt> request, submitted with the user name and password
* of the current user.
*
* The global JosmUserStateManager listens to {@see PreferenceChangeEvent}s and keeps track
* of what the current JOSM instance knows about the current user. Other subsystems can
* let the global JosmUserStateManager know in case they fully identify the current user, see
* {@see #setFullyIdentified(String, long)}.
*
* The information kept by the JosmUserStateManager can be used to
* <ul>
* <li>safely query changesets owned by the current user based on its user id, not on its user name</li>
* <li>safely search for objects last touched by the current user based on its user id, not on its user name</li>
* </ul>
*
*/
public class JosmUserIdentityManager implements PreferenceChangedListener{
static private JosmUserIdentityManager instance;
/**
* Replies the unique instance of the JOSM user identity manager
*
* @return the unique instance of the JOSM user identity manager
*/
static public JosmUserIdentityManager getInstance() {
if (instance == null) {
instance = new JosmUserIdentityManager();
instance.initFromPreferences();
Main.pref.addPreferenceChangeListener(instance);
}
return instance;
}
private String userName;
private UserInfo userInfo;
private JosmUserIdentityManager() {
}
/**
* Remembers the fact that the current JOSM user is anonymous.
*/
public void setAnonymous() {
userName = null;
userInfo = null;
}
/**
* Remebers the fact that the current JOSM user is partially identified
* by the user name of its OSM account.
*
* @param userName the user name. Must not be null. Must not be empty (whitespace only).
* @throws IllegalArgumentException thrown if userName is null
* @throws IllegalArgumentException thrown if userName is empty
*/
public void setPartiallyIdentified(String userName) throws IllegalArgumentException {
CheckParameterUtil.ensureParameterNotNull(userName, "userName");
if (userName.trim().equals(""))
throw new IllegalArgumentException(MessageFormat.format("Expected non-empty value for parameter ''{0}'', got ''{1}''", "userName", userName));
this.userName = userName;
userInfo = null;
}
/**
* Remembers the fact that the current JOSM user is fully identified with a
* verified pair of user name and user id.
*
* @param userName the user name. Must not be null. Must not be empty.
* @param userinfo additional information about the user, retrieved from the OSM server and including the user id
* @throws IllegalArgumentException thrown if userName is null
* @throws IllegalArgumentException thrown if userName is empty
* @throws IllegalArgumentException thrown if userinfo is null
*/
public void setFullyIdentified(String username, UserInfo userinfo) throws IllegalArgumentException {
CheckParameterUtil.ensureParameterNotNull(username, "username");
if (username.trim().equals(""))
throw new IllegalArgumentException(tr("Expected non-empty value for parameter ''{0}'', got ''{1}''", "userName", userName));
CheckParameterUtil.ensureParameterNotNull(userinfo, "userinfo");
this.userName = username;
this.userInfo = userinfo;
}
/**
* Replies true if the current JOSM user is anonymous.
*
* @return true if the current user is anonymous.
*/
public boolean isAnonymous() {
return userName == null && userInfo == null;
}
/**
* Replies true if the current JOSM user is partially identified.
*
* @return true if the current JOSM user is partially identified.
*/
public boolean isPartiallyIdentified() {
return userName != null && userInfo == null;
}
/**
* Replies true if the current JOSM user is fully identified.
*
* @return true if the current JOSM user is fully identified.
*/
public boolean isFullyIdentified() {
return userName != null && userInfo != null;
}
/**
* Replies the user name of the current JOSM user. null, if {@see #isAnonymous()} is true.
*
* @return the user name of the current JOSM user
*/
public String getUserName() {
return userName;
}
/**
* Replies the user id of the current JOSM user. 0, if {@see #isAnonymous()} or
* {@see #isPartiallyIdentified()} is true.
*
* @return the user id of the current JOSM user
*/
public int getUserId() {
if (userInfo == null) return 0;
return userInfo.getId();
}
/**
* Replies verified additional information about the current user if the user is
* {@see #isFullyIdentified()}.
*
* @return verified additional information about the current user
*/
public UserInfo getUserInfo() {
return userInfo;
}
/**
* Initializes the user identity manager from values in the {@see org.openstreetmap.josm.data.Preferences}
*/
public void initFromPreferences() {
String userName = Main.pref.get("osm-server.username");
if (isAnonymous()) {
if (userName != null && ! userName.trim().equals("")) {
setPartiallyIdentified(userName);
}
} else {
if (!userName.equals(this.userName)) {
setPartiallyIdentified(userName);
} else {
// same name in the preferences as JOSM already knows about;
// keep the state, be it partially or fully identified
}
}
}
/**
* Replies true if the user with name <code>username</code> is the current
* user
*
* @param username the user name
* @return true if the user with name <code>username</code> is the current
* user
*/
public boolean isCurrentUser(String username) {
if (username == null || this.userName == null) return false;
return this.userName.equals(username);
}
/* ------------------------------------------------------------------- */
/* interface PreferenceChangeListener */
/* ------------------------------------------------------------------- */
public void preferenceChanged(PreferenceChangeEvent evt) {
if (evt.getKey().equals("osm-server.username")) {
String newValue = evt.getNewValue();
if (newValue == null || newValue.trim().length() == 0) {
setAnonymous();
} else {
if (! newValue.equals(userName)) {
setPartiallyIdentified(newValue);
}
}
return;
}
if (evt.getKey().equals("osm-server.url")) {
String newValue = evt.getNewValue();
if (newValue == null || newValue.trim().equals("")) {
setAnonymous();
} else if (isFullyIdentified()) {
setPartiallyIdentified(getUserName());
}
}
}
}