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.home;
michael@0: 
michael@0: import java.util.ArrayList;
michael@0: import java.util.List;
michael@0: import java.util.Set;
michael@0: import java.util.concurrent.atomic.AtomicInteger;
michael@0: 
michael@0: import org.json.JSONArray;
michael@0: import org.json.JSONException;
michael@0: import org.json.JSONObject;
michael@0: import org.mozilla.gecko.GeckoAppShell;
michael@0: import org.mozilla.gecko.GeckoEvent;
michael@0: import org.mozilla.gecko.home.HomeConfig.PanelConfig;
michael@0: import org.mozilla.gecko.util.GeckoEventListener;
michael@0: import org.mozilla.gecko.util.ThreadUtils;
michael@0: 
michael@0: import android.util.Log;
michael@0: import android.util.SparseArray;
michael@0: 
michael@0: public class PanelInfoManager implements GeckoEventListener {
michael@0:     private static final String LOGTAG = "GeckoPanelInfoManager";
michael@0: 
michael@0:     public class PanelInfo {
michael@0:         private final String mId;
michael@0:         private final String mTitle;
michael@0:         private final JSONObject mJSONData;
michael@0: 
michael@0:         public PanelInfo(String id, String title, JSONObject jsonData) {
michael@0:             mId = id;
michael@0:             mTitle = title;
michael@0:             mJSONData = jsonData;
michael@0:         }
michael@0: 
michael@0:         public String getId() {
michael@0:             return mId;
michael@0:         }
michael@0: 
michael@0:         public String getTitle() {
michael@0:             return mTitle;
michael@0:         }
michael@0: 
michael@0:         public PanelConfig toPanelConfig() {
michael@0:             try {
michael@0:                 return new PanelConfig(mJSONData);
michael@0:             } catch (Exception e) {
michael@0:                 Log.e(LOGTAG, "Failed to convert PanelInfo to PanelConfig", e);
michael@0:                 return null;
michael@0:             }
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     public interface RequestCallback {
michael@0:         public void onComplete(List<PanelInfo> panelInfos);
michael@0:     }
michael@0: 
michael@0:     private static AtomicInteger sRequestId = new AtomicInteger(0);
michael@0: 
michael@0:     // Stores set of pending request callbacks.
michael@0:     private static final SparseArray<RequestCallback> sCallbacks = new SparseArray<RequestCallback>();
michael@0: 
michael@0:     /**
michael@0:      * Asynchronously fetches list of available panels from Gecko
michael@0:      * for the given IDs.
michael@0:      *
michael@0:      * @param ids list of panel ids to be fetched. A null value will fetch all
michael@0:      *        available panels.
michael@0:      * @param callback onComplete will be called on the UI thread.
michael@0:      */
michael@0:     public void requestPanelsById(Set<String> ids, RequestCallback callback) {
michael@0:         final int requestId = sRequestId.getAndIncrement();
michael@0: 
michael@0:         synchronized(sCallbacks) {
michael@0:             // If there are no pending callbacks, register the event listener.
michael@0:             if (sCallbacks.size() == 0) {
michael@0:                 GeckoAppShell.getEventDispatcher().registerEventListener("HomePanels:Data", this);
michael@0:             }
michael@0:             sCallbacks.put(requestId, callback);
michael@0:         }
michael@0: 
michael@0:         final JSONObject message = new JSONObject();
michael@0:         try {
michael@0:             message.put("requestId", requestId);
michael@0: 
michael@0:             if (ids != null && ids.size() > 0) {
michael@0:                 JSONArray idsArray = new JSONArray();
michael@0:                 for (String id : ids) {
michael@0:                     idsArray.put(id);
michael@0:                 }
michael@0: 
michael@0:                 message.put("ids", idsArray);
michael@0:             }
michael@0:         } catch (JSONException e) {
michael@0:             Log.e(LOGTAG, "Failed to build event to request panels by id", e);
michael@0:             return;
michael@0:         }
michael@0: 
michael@0:         GeckoAppShell.sendEventToGecko(GeckoEvent.createBroadcastEvent("HomePanels:Get", message.toString()));
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Asynchronously fetches list of available panels from Gecko.
michael@0:      *
michael@0:      * @param callback onComplete will be called on the UI thread.
michael@0:      */
michael@0:     public void requestAvailablePanels(RequestCallback callback) {
michael@0:         requestPanelsById(null, callback);
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Handles "HomePanels:Data" events.
michael@0:      */
michael@0:     @Override
michael@0:     public void handleMessage(String event, JSONObject message) {
michael@0:         final ArrayList<PanelInfo> panelInfos = new ArrayList<PanelInfo>();
michael@0: 
michael@0:         try {
michael@0:             final JSONArray panels = message.getJSONArray("panels");
michael@0:             final int count = panels.length();
michael@0:             for (int i = 0; i < count; i++) {
michael@0:                 final PanelInfo panelInfo = getPanelInfoFromJSON(panels.getJSONObject(i));
michael@0:                 panelInfos.add(panelInfo);
michael@0:             }
michael@0: 
michael@0:             final RequestCallback callback;
michael@0:             final int requestId = message.getInt("requestId");
michael@0: 
michael@0:             synchronized(sCallbacks) {
michael@0:                 callback = sCallbacks.get(requestId);
michael@0:                 sCallbacks.delete(requestId);
michael@0: 
michael@0:                 // Unregister the event listener if there are no more pending callbacks.
michael@0:                 if (sCallbacks.size() == 0) {
michael@0:                     GeckoAppShell.getEventDispatcher().unregisterEventListener("HomePanels:Data", this);
michael@0:                 }
michael@0:             }
michael@0: 
michael@0:             ThreadUtils.postToUiThread(new Runnable() {
michael@0:                 @Override
michael@0:                 public void run() {
michael@0:                     callback.onComplete(panelInfos);
michael@0:                 }
michael@0:             });
michael@0:         } catch (JSONException e) {
michael@0:             Log.e(LOGTAG, "Exception handling " + event + " message", e);
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     private PanelInfo getPanelInfoFromJSON(JSONObject jsonPanelInfo) throws JSONException {
michael@0:         final String id = jsonPanelInfo.getString("id");
michael@0:         final String title = jsonPanelInfo.getString("title");
michael@0: 
michael@0:         return new PanelInfo(id, title, jsonPanelInfo);
michael@0:     }
michael@0: }