michael@0: /* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
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.EventDispatcher;
michael@0: import org.mozilla.gecko.util.GeckoEventListener;
michael@0: 
michael@0: import org.json.JSONArray;
michael@0: import org.json.JSONException;
michael@0: import org.json.JSONObject;
michael@0: 
michael@0: import android.content.Context;
michael@0: import android.content.SharedPreferences;
michael@0: import android.util.Log;
michael@0: 
michael@0: import java.util.Map;
michael@0: import java.util.HashMap;
michael@0: 
michael@0: /**
michael@0:  * Helper class to get, set, and observe Android Shared Preferences.
michael@0:  */
michael@0: public final class SharedPreferencesHelper
michael@0:              implements GeckoEventListener
michael@0: {
michael@0:     public static final String LOGTAG = "GeckoAndSharedPrefs";
michael@0: 
michael@0:     protected final Context mContext;
michael@0: 
michael@0:     // mListeners is not synchronized because it is only updated in
michael@0:     // handleObserve, which is called from Gecko serially.
michael@0:     protected final Map<String, SharedPreferences.OnSharedPreferenceChangeListener> mListeners;
michael@0: 
michael@0:     public SharedPreferencesHelper(Context context) {
michael@0:         mContext = context;
michael@0: 
michael@0:         mListeners = new HashMap<String, SharedPreferences.OnSharedPreferenceChangeListener>();
michael@0: 
michael@0:         EventDispatcher dispatcher = GeckoAppShell.getEventDispatcher();
michael@0:         if (dispatcher == null) {
michael@0:             Log.e(LOGTAG, "Gecko event dispatcher must not be null", new RuntimeException());
michael@0:             return;
michael@0:         }
michael@0:         dispatcher.registerEventListener("SharedPreferences:Set", this);
michael@0:         dispatcher.registerEventListener("SharedPreferences:Get", this);
michael@0:         dispatcher.registerEventListener("SharedPreferences:Observe", this);
michael@0:     }
michael@0: 
michael@0:     public synchronized void uninit() {
michael@0:         EventDispatcher dispatcher = GeckoAppShell.getEventDispatcher();
michael@0:         if (dispatcher == null) {
michael@0:             Log.e(LOGTAG, "Gecko event dispatcher must not be null", new RuntimeException());
michael@0:             return;
michael@0:         }
michael@0: 
michael@0:         dispatcher.unregisterEventListener("SharedPreferences:Set", this);
michael@0:         dispatcher.unregisterEventListener("SharedPreferences:Get", this);
michael@0:         dispatcher.unregisterEventListener("SharedPreferences:Observe", this);
michael@0:     }
michael@0: 
michael@0:     private SharedPreferences getSharedPreferences(String branch) {
michael@0:         if (branch == null) {
michael@0:             return GeckoSharedPrefs.forApp(mContext);
michael@0:         } else {
michael@0:             return mContext.getSharedPreferences(branch, Context.MODE_PRIVATE);
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Set many SharedPreferences in Android.
michael@0:      *
michael@0:      * message.branch must exist, and should be a String SharedPreferences
michael@0:      * branch name, or null for the default branch.
michael@0:      * message.preferences should be an array of preferences.  Each preference
michael@0:      * must include a String name, a String type in ["bool", "int", "string"],
michael@0:      * and an Object value.
michael@0:      */
michael@0:     private void handleSet(JSONObject message) throws JSONException {
michael@0:         if (!message.has("branch")) {
michael@0:             Log.e(LOGTAG, "No branch specified for SharedPreference:Set; aborting.");
michael@0:             return;
michael@0:         }
michael@0: 
michael@0:         String branch = message.isNull("branch") ? null : message.getString("branch");
michael@0:         SharedPreferences.Editor editor = getSharedPreferences(branch).edit();
michael@0: 
michael@0:         JSONArray jsonPrefs = message.getJSONArray("preferences");
michael@0: 
michael@0:         for (int i = 0; i < jsonPrefs.length(); i++) {
michael@0:             JSONObject pref = jsonPrefs.getJSONObject(i);
michael@0:             String name = pref.getString("name");
michael@0:             String type = pref.getString("type");
michael@0:             if ("bool".equals(type)) {
michael@0:                 editor.putBoolean(name, pref.getBoolean("value"));
michael@0:             } else if ("int".equals(type)) {
michael@0:                 editor.putInt(name, pref.getInt("value"));
michael@0:             } else if ("string".equals(type)) {
michael@0:                 editor.putString(name, pref.getString("value"));
michael@0:             } else {
michael@0:                 Log.w(LOGTAG, "Unknown pref value type [" + type + "] for pref [" + name + "]");
michael@0:             }
michael@0:             editor.commit();
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Get many SharedPreferences from Android.
michael@0:      *
michael@0:      * message.branch must exist, and should be a String SharedPreferences
michael@0:      * branch name, or null for the default branch.
michael@0:      * message.preferences should be an array of preferences.  Each preference
michael@0:      * must include a String name, and a String type in ["bool", "int",
michael@0:      * "string"].
michael@0:      */
michael@0:     private JSONArray handleGet(JSONObject message) throws JSONException {
michael@0:         if (!message.has("branch")) {
michael@0:             Log.e(LOGTAG, "No branch specified for SharedPreference:Get; aborting.");
michael@0:             return null;
michael@0:         }
michael@0: 
michael@0:         String branch = message.isNull("branch") ? null : message.getString("branch");
michael@0:         SharedPreferences prefs = getSharedPreferences(branch);
michael@0:         JSONArray jsonPrefs = message.getJSONArray("preferences");
michael@0:         JSONArray jsonValues = new JSONArray();
michael@0: 
michael@0:         for (int i = 0; i < jsonPrefs.length(); i++) {
michael@0:             JSONObject pref = jsonPrefs.getJSONObject(i);
michael@0:             String name = pref.getString("name");
michael@0:             String type = pref.getString("type");
michael@0:             JSONObject jsonValue = new JSONObject();
michael@0:             jsonValue.put("name", name);
michael@0:             jsonValue.put("type", type);
michael@0:             try {
michael@0:                 if ("bool".equals(type)) {
michael@0:                     boolean value = prefs.getBoolean(name, false);
michael@0:                     jsonValue.put("value", value);
michael@0:                 } else if ("int".equals(type)) {
michael@0:                     int value = prefs.getInt(name, 0);
michael@0:                     jsonValue.put("value", value);
michael@0:                 } else if ("string".equals(type)) {
michael@0:                     String value = prefs.getString(name, "");
michael@0:                     jsonValue.put("value", value);
michael@0:                 } else {
michael@0:                     Log.w(LOGTAG, "Unknown pref value type [" + type + "] for pref [" + name + "]");
michael@0:                 }
michael@0:             } catch (ClassCastException e) {
michael@0:                 // Thrown if there is a preference with the given name that is
michael@0:                 // not the right type.
michael@0:                 Log.w(LOGTAG, "Wrong pref value type [" + type + "] for pref [" + name + "]");
michael@0:             }
michael@0:             jsonValues.put(jsonValue);
michael@0:         }
michael@0: 
michael@0:         return jsonValues;
michael@0:     }
michael@0: 
michael@0:     private static class ChangeListener
michael@0:         implements SharedPreferences.OnSharedPreferenceChangeListener {
michael@0:         public final String branch;
michael@0: 
michael@0:         public ChangeListener(final String branch) {
michael@0:             this.branch = branch;
michael@0:         }
michael@0: 
michael@0:         @Override
michael@0:         public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
michael@0:             if (Log.isLoggable(LOGTAG, Log.VERBOSE)) {
michael@0:                 Log.v(LOGTAG, "Got onSharedPreferenceChanged");
michael@0:             }
michael@0:             try {
michael@0:                 final JSONObject msg = new JSONObject();
michael@0:                 msg.put("branch", this.branch);
michael@0:                 msg.put("key", key);
michael@0: 
michael@0:                 // Truly, this is awful, but the API impedence is strong: there
michael@0:                 // is no way to get a single untyped value from a
michael@0:                 // SharedPreferences instance.
michael@0:                 msg.put("value", sharedPreferences.getAll().get(key));
michael@0: 
michael@0:                 GeckoAppShell.sendEventToGecko(GeckoEvent.createBroadcastEvent("SharedPreferences:Changed", msg.toString()));
michael@0:             } catch (JSONException e) {
michael@0:                 Log.e(LOGTAG, "Got exception creating JSON object", e);
michael@0:                 return;
michael@0:             }
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Register or unregister a SharedPreferences.OnSharedPreferenceChangeListener.
michael@0:      *
michael@0:      * message.branch must exist, and should be a String SharedPreferences
michael@0:      * branch name, or null for the default branch.
michael@0:      * message.enable should be a boolean: true to enable listening, false to
michael@0:      * disable listening.
michael@0:      */
michael@0:     private void handleObserve(JSONObject message) throws JSONException {
michael@0:         if (!message.has("branch")) {
michael@0:             Log.e(LOGTAG, "No branch specified for SharedPreference:Observe; aborting.");
michael@0:             return;
michael@0:         }
michael@0: 
michael@0:         String branch = message.isNull("branch") ? null : message.getString("branch");
michael@0:         SharedPreferences prefs = getSharedPreferences(branch);
michael@0:         boolean enable = message.getBoolean("enable");
michael@0: 
michael@0:         // mListeners is only modified in this one observer, which is called
michael@0:         // from Gecko serially.
michael@0:         if (enable && !this.mListeners.containsKey(branch)) {
michael@0:             SharedPreferences.OnSharedPreferenceChangeListener listener = new ChangeListener(branch);
michael@0:             this.mListeners.put(branch, listener);
michael@0:             prefs.registerOnSharedPreferenceChangeListener(listener);
michael@0:         }
michael@0:         if (!enable && this.mListeners.containsKey(branch)) {
michael@0:             SharedPreferences.OnSharedPreferenceChangeListener listener = this.mListeners.remove(branch);
michael@0:             prefs.unregisterOnSharedPreferenceChangeListener(listener);
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     public void handleMessage(String event, JSONObject message) {
michael@0:         // Everything here is synchronous and serial, so we need not worry about
michael@0:         // overwriting an in-progress response.
michael@0:         try {
michael@0:             if (event.equals("SharedPreferences:Set")) {
michael@0:                 if (Log.isLoggable(LOGTAG, Log.VERBOSE)) {
michael@0:                     Log.v(LOGTAG, "Got SharedPreferences:Set message.");
michael@0:                 }
michael@0:                 handleSet(message);
michael@0:             } else if (event.equals("SharedPreferences:Get")) {
michael@0:                 if (Log.isLoggable(LOGTAG, Log.VERBOSE)) {
michael@0:                     Log.v(LOGTAG, "Got SharedPreferences:Get message.");
michael@0:                 }
michael@0:                 JSONObject obj = new JSONObject();
michael@0:                 obj.put("values", handleGet(message));
michael@0:                 EventDispatcher.sendResponse(message, obj);
michael@0:             } else if (event.equals("SharedPreferences:Observe")) {
michael@0:                 if (Log.isLoggable(LOGTAG, Log.VERBOSE)) {
michael@0:                     Log.v(LOGTAG, "Got SharedPreferences:Observe message.");
michael@0:                 }
michael@0:                 handleObserve(message);
michael@0:             } else {
michael@0:                 Log.e(LOGTAG, "SharedPreferencesHelper got unexpected message " + event);
michael@0:                 return;
michael@0:             }
michael@0:         } catch (JSONException e) {
michael@0:             Log.e(LOGTAG, "Got exception in handleMessage handling event " + event, e);
michael@0:             return;
michael@0:         }
michael@0:     }
michael@0: }