michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: package org.mozilla.gecko;
michael@0: 
michael@0: import org.mozilla.gecko.mozglue.RobocopTarget;
michael@0: import org.mozilla.gecko.util.ThreadUtils;
michael@0: 
michael@0: import android.content.Context;
michael@0: import android.content.SharedPreferences;
michael@0: import android.content.SharedPreferences.Editor;
michael@0: import android.os.Build;
michael@0: import android.os.StrictMode;
michael@0: import android.preference.PreferenceManager;
michael@0: import android.util.Log;
michael@0: 
michael@0: import java.util.Arrays;
michael@0: import java.util.EnumSet;
michael@0: import java.util.List;
michael@0: import java.util.Map;
michael@0: import java.util.Set;
michael@0: 
michael@0: /**
michael@0:  * {@code GeckoSharedPrefs} provides scoped SharedPreferences instances.
michael@0:  * You should use this API instead of using Context.getSharedPreferences()
michael@0:  * directly. There are three methods to get scoped SharedPreferences instances:
michael@0:  *
michael@0:  * forApp()
michael@0:  *     Use it for app-wide, cross-profile pref keys.
michael@0:  * forProfile()
michael@0:  *     Use it to fetch and store keys for the current profile.
michael@0:  * forProfileName()
michael@0:  *     Use it to fetch and store keys from/for a specific profile.
michael@0:  *
michael@0:  * {@code GeckoSharedPrefs} has a notion of migrations. Migrations can used to
michael@0:  * migrate keys from one scope to another. You can trigger a new migration by
michael@0:  * incrementing PREFS_VERSION and updating migrateIfNecessary() accordingly.
michael@0:  *
michael@0:  * Migration history:
michael@0:  *     1: Move all PreferenceManager keys to app/profile scopes
michael@0:  */
michael@0: @RobocopTarget
michael@0: public final class GeckoSharedPrefs {
michael@0:     private static final String LOGTAG = "GeckoSharedPrefs";
michael@0: 
michael@0:     // Increment it to trigger a new migration
michael@0:     public static final int PREFS_VERSION = 1;
michael@0: 
michael@0:     // Name for app-scoped prefs
michael@0:     public static final String APP_PREFS_NAME = "GeckoApp";
michael@0: 
michael@0:     // The prefs key that holds the current migration
michael@0:     private static final String PREFS_VERSION_KEY = "gecko_shared_prefs_migration";
michael@0: 
michael@0:     // For disabling migration when getting a SharedPreferences instance
michael@0:     private static final EnumSet<Flags> disableMigrations = EnumSet.of(Flags.DISABLE_MIGRATIONS);
michael@0: 
michael@0:     // Timeout for migration commits to be done (10 seconds)
michael@0:     private static final int MIGRATION_COMMIT_TIMEOUT_MSEC = 10000;
michael@0: 
michael@0:     // The keys that have to be moved from ProfileManager's default
michael@0:     // shared prefs to the profile from version 0 to 1.
michael@0:     private static final String[] PROFILE_MIGRATIONS_0_TO_1 = {
michael@0:         "home_panels",
michael@0:         "home_locale"
michael@0:     };
michael@0: 
michael@0:     // For optimizing the migration check in subsequent get() calls
michael@0:     private static volatile boolean migrationDone = false;
michael@0: 
michael@0:     public enum Flags {
michael@0:         DISABLE_MIGRATIONS
michael@0:     }
michael@0: 
michael@0:     // Used when fetching profile-scoped prefs.
michael@0:     private static final String PROFILE_PREFS_NAME_PREFIX = "GeckoProfile-";
michael@0: 
michael@0:     public static SharedPreferences forApp(Context context) {
michael@0:         return forApp(context, EnumSet.noneOf(Flags.class));
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Returns an app-scoped SharedPreferences instance. You can disable
michael@0:      * migrations by using the DISABLE_MIGRATIONS flag.
michael@0:      */
michael@0:     public static SharedPreferences forApp(Context context, EnumSet<Flags> flags) {
michael@0:         if (flags != null && !flags.contains(Flags.DISABLE_MIGRATIONS)) {
michael@0:             migrateIfNecessary(context);
michael@0:         }
michael@0: 
michael@0:         return context.getSharedPreferences(APP_PREFS_NAME, 0);
michael@0:     }
michael@0: 
michael@0:     public static SharedPreferences forProfile(Context context) {
michael@0:         return forProfile(context, EnumSet.noneOf(Flags.class));
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Returns a SharedPreferences instance scoped to the current profile
michael@0:      * in the app. You can disable migrations by using the DISABLE_MIGRATIONS
michael@0:      * flag.
michael@0:      */
michael@0:     public static SharedPreferences forProfile(Context context, EnumSet<Flags> flags) {
michael@0:         String profileName = GeckoProfile.get(context).getName();
michael@0:         if (profileName == null) {
michael@0:             throw new IllegalStateException("Could not get current profile name");
michael@0:         }
michael@0: 
michael@0:         return forProfileName(context, profileName, flags);
michael@0:     }
michael@0: 
michael@0:     public static SharedPreferences forProfileName(Context context, String profileName) {
michael@0:         return forProfileName(context, profileName, EnumSet.noneOf(Flags.class));
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Returns an SharedPreferences instance scoped to the given profile name.
michael@0:      * You can disable migrations by using the DISABLE_MIGRATION flag.
michael@0:      */
michael@0:     public static SharedPreferences forProfileName(Context context, String profileName,
michael@0:             EnumSet<Flags> flags) {
michael@0:         if (flags != null && !flags.contains(Flags.DISABLE_MIGRATIONS)) {
michael@0:             migrateIfNecessary(context);
michael@0:         }
michael@0: 
michael@0:         final String prefsName = PROFILE_PREFS_NAME_PREFIX + profileName;
michael@0:         return context.getSharedPreferences(prefsName, 0);
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Returns the current version of the prefs.
michael@0:      */
michael@0:     public static int getVersion(Context context) {
michael@0:         return forApp(context, disableMigrations).getInt(PREFS_VERSION_KEY, 0);
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Resets migration flag. Should only be used in tests.
michael@0:      */
michael@0:     public static synchronized void reset() {
michael@0:         migrationDone = false;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Performs all prefs migrations in the background thread to avoid StrictMode
michael@0:      * exceptions from reading/writing in the UI thread. This method will block
michael@0:      * the current thread until the migration is finished.
michael@0:      */
michael@0:     private static synchronized void migrateIfNecessary(final Context context) {
michael@0:         if (migrationDone) {
michael@0:             return;
michael@0:         }
michael@0: 
michael@0:         // We deliberatly perform the migration in the current thread (which
michael@0:         // is likely the UI thread) as this is actually cheaper than enforcing a
michael@0:         // context switch to another thread (see bug 940575).
michael@0:         if (Build.VERSION.SDK_INT < 9) {
michael@0:             performMigration(context);
michael@0:         } else {
michael@0:             // Avoid strict mode warnings.
michael@0:             final StrictMode.ThreadPolicy savedPolicy = StrictMode.allowThreadDiskReads();
michael@0:             StrictMode.allowThreadDiskWrites();
michael@0: 
michael@0:             try {
michael@0:                 performMigration(context);
michael@0:             } finally {
michael@0:                 StrictMode.setThreadPolicy(savedPolicy);
michael@0:             }
michael@0:         }
michael@0: 
michael@0:         migrationDone = true;
michael@0:     }
michael@0: 
michael@0:     private static void performMigration(Context context) {
michael@0:         final SharedPreferences appPrefs = forApp(context, disableMigrations);
michael@0: 
michael@0:         final int currentVersion = appPrefs.getInt(PREFS_VERSION_KEY, 0);
michael@0:         Log.d(LOGTAG, "Current version = " + currentVersion + ", prefs version = " + PREFS_VERSION);
michael@0: 
michael@0:         if (currentVersion == PREFS_VERSION) {
michael@0:             return;
michael@0:         }
michael@0: 
michael@0:         Log.d(LOGTAG, "Performing migration");
michael@0: 
michael@0:         final Editor appEditor = appPrefs.edit();
michael@0: 
michael@0:         // The migration always moves prefs to the default profile, not
michael@0:         // the current one. We might have to revisit this if we ever support
michael@0:         // multiple profiles.
michael@0:         final String defaultProfileName;
michael@0:         try {
michael@0:             defaultProfileName = GeckoProfile.getDefaultProfileName(context);
michael@0:         } catch (Exception e) {
michael@0:             throw new IllegalStateException("Failed to get default profile name for migration");
michael@0:         }
michael@0: 
michael@0:         final Editor profileEditor = forProfileName(context, defaultProfileName, disableMigrations).edit();
michael@0: 
michael@0:         List<String> profileKeys;
michael@0:         Editor pmEditor = null;
michael@0: 
michael@0:         for (int v = currentVersion + 1; v <= PREFS_VERSION; v++) {
michael@0:             Log.d(LOGTAG, "Migrating to version = " + v);
michael@0: 
michael@0:             switch (v) {
michael@0:                 case 1:
michael@0:                     profileKeys = Arrays.asList(PROFILE_MIGRATIONS_0_TO_1);
michael@0:                     pmEditor = migrateFromPreferenceManager(context, appEditor, profileEditor, profileKeys);
michael@0:                     break;
michael@0:             }
michael@0:         }
michael@0: 
michael@0:         // Update prefs version accordingly.
michael@0:         appEditor.putInt(PREFS_VERSION_KEY, PREFS_VERSION);
michael@0: 
michael@0:         appEditor.commit();
michael@0:         profileEditor.commit();
michael@0:         if (pmEditor != null) {
michael@0:             pmEditor.commit();
michael@0:         }
michael@0: 
michael@0:         Log.d(LOGTAG, "All keys have been migrated");
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Moves all preferences stored in PreferenceManager's default prefs
michael@0:      * to either app or profile scopes. The profile-scoped keys are defined
michael@0:      * in given profileKeys list, all other keys are moved to the app scope.
michael@0:      */
michael@0:     public static Editor migrateFromPreferenceManager(Context context, Editor appEditor,
michael@0:             Editor profileEditor, List<String> profileKeys) {
michael@0:         Log.d(LOGTAG, "Migrating from PreferenceManager");
michael@0: 
michael@0:         final SharedPreferences pmPrefs =
michael@0:                 PreferenceManager.getDefaultSharedPreferences(context);
michael@0: 
michael@0:         for (Map.Entry<String, ?> entry : pmPrefs.getAll().entrySet()) {
michael@0:             final String key = entry.getKey();
michael@0: 
michael@0:             final Editor to;
michael@0:             if (profileKeys.contains(key)) {
michael@0:                 to = profileEditor;
michael@0:             } else {
michael@0:                 to = appEditor;
michael@0:             }
michael@0: 
michael@0:             putEntry(to, key, entry.getValue());
michael@0:         }
michael@0: 
michael@0:         // Clear PreferenceManager's prefs once we're done
michael@0:         // and return the Editor to be committed.
michael@0:         return pmPrefs.edit().clear();
michael@0:     }
michael@0: 
michael@0:     @SuppressWarnings("unchecked")
michael@0:     private static void putEntry(Editor to, String key, Object value) {
michael@0:         Log.d(LOGTAG, "Migrating key = " + key + " with value = " + value);
michael@0: 
michael@0:         if (value instanceof String) {
michael@0:             to.putString(key, (String) value);
michael@0:         } else if (value instanceof Boolean) {
michael@0:             to.putBoolean(key, (Boolean) value);
michael@0:         } else if (value instanceof Long) {
michael@0:             to.putLong(key, (Long) value);
michael@0:         } else if (value instanceof Float) {
michael@0:             to.putFloat(key, (Float) value);
michael@0:         } else if (value instanceof Integer) {
michael@0:             to.putInt(key, (Integer) value);
michael@0:         } else {
michael@0:             throw new IllegalStateException("Unrecognized value type for key: " + key);
michael@0:         }
michael@0:     }
michael@0: }