edu.cmu.sv.trailscribe.controller.SynchronizationCenterController.java Source code

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Here is the source code for edu.cmu.sv.trailscribe.controller.SynchronizationCenterController.java

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/* 
 * Copyright (c) 2014, TrailScribe Team.
 * This content is released under the MIT License. See the file named LICENSE for details.
 */
package edu.cmu.sv.trailscribe.controller;

import java.util.ArrayList;
import java.util.List;

import android.os.AsyncTask;

import com.google.gson.GsonBuilder;
import com.google.gson.JsonArray;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;

import edu.cmu.sv.trailscribe.dao.KmlDataSource;
import edu.cmu.sv.trailscribe.dao.MapDataSource;
import edu.cmu.sv.trailscribe.model.AsyncTaskCompleteListener;
import edu.cmu.sv.trailscribe.model.data.Kml;
import edu.cmu.sv.trailscribe.model.data.Map;
import edu.cmu.sv.trailscribe.model.data.SyncItem;
import edu.cmu.sv.trailscribe.utils.BackendFacade;
import edu.cmu.sv.trailscribe.utils.SyncItemSerializer;
import edu.cmu.sv.trailscribe.view.TrailScribeApplication;

public class SynchronizationCenterController extends AsyncTask<String, Void, Void>
        implements AsyncTaskCompleteListener<String> {

    private final String endpoint = "http://trail-scribe.mlep.net/sync/";
    private AsyncTaskCompleteListener<ArrayList<SyncItem>> mTaskCompletedCallback;
    MapDataSource mMapsDataSource = new MapDataSource(TrailScribeApplication.getDBHelper());
    KmlDataSource mKmlsDataSource = new KmlDataSource(TrailScribeApplication.getDBHelper());
    BackendFacade mBackendFacade;

    public SynchronizationCenterController(AsyncTaskCompleteListener<ArrayList<SyncItem>> callback) {
        this.mTaskCompletedCallback = callback;
    }

    // This method is invoked by the BackendFacade once the response from the backend is available
    @Override
    public void onTaskCompleted(String syncResult) {
        if (mBackendFacade != null) {
            mBackendFacade.cancel(true);
        }
        ArrayList<SyncItem> itemsToSync = null;

        JsonParser jsonParser = new JsonParser();
        JsonElement jsonElement = jsonParser.parse(syncResult);

        // Unless there is an error in the communication, jsonElement should not be null
        if (!jsonElement.isJsonNull()) {
            JsonArray syncResultJson = (JsonArray) jsonParser.parse(syncResult);
            itemsToSync = new ArrayList<SyncItem>();
            for (JsonElement item : syncResultJson) {
                String model = item.getAsJsonObject().get("model").getAsString();
                JsonObject syncItemJsonArray = item.getAsJsonObject().get("fields").getAsJsonObject();

                // Parsing maps and kmls differently given their attributes are not quite the same
                if (model.equals("sync_center.map")) {
                    itemsToSync.add(parseMapInformation(item, syncItemJsonArray));
                } else if (model.equals("sync_center.kml")) {
                    itemsToSync.add(parseKmlInformation(item, syncItemJsonArray));
                }
            }
        }
        mTaskCompletedCallback.onTaskCompleted(itemsToSync);
    }

    private Kml parseKmlInformation(JsonElement item, JsonObject syncItemJsonArray) {
        Kml kml;
        kml = new Kml();
        kml.setName(syncItemJsonArray.get("name").getAsString());
        kml.setId(item.getAsJsonObject().get("pk").getAsLong());
        kml.setFilename(syncItemJsonArray.get("filename").getAsString());
        kml.setLastModified(syncItemJsonArray.get("last_modified").getAsString());
        return kml;
    }

    private Map parseMapInformation(JsonElement item, JsonObject syncItemJsonArray) {
        Map map;
        map = new Map();
        map.setId(item.getAsJsonObject().get("pk").getAsLong());
        map.setMinX(syncItemJsonArray.get("min_x").getAsDouble());
        map.setMaxZoomLevel(syncItemJsonArray.get("max_zoom_level").getAsInt());
        map.setMaxY(syncItemJsonArray.get("max_y").getAsDouble());
        map.setName(syncItemJsonArray.get("name").getAsString());
        map.setFilename(syncItemJsonArray.get("filename").getAsString());
        map.setProjection(syncItemJsonArray.get("projection").getAsString());
        map.setLastModified(syncItemJsonArray.get("last_modified").getAsString());
        map.setMinZoomLevel(syncItemJsonArray.get("min_zoom_level").getAsInt());
        map.setMaxX(syncItemJsonArray.get("max_x").getAsDouble());
        map.setMinY(syncItemJsonArray.get("min_y").getAsDouble());
        return map;
    }

    @Override
    protected Void doInBackground(String... params) {
        List<SyncItem> syncItems = new ArrayList<SyncItem>();
        syncItems.addAll(mMapsDataSource.getAll());
        syncItems.addAll(mKmlsDataSource.getAll());

        GsonBuilder gson = new GsonBuilder();
        gson.registerTypeAdapter(ArrayList.class, new SyncItemSerializer());
        String json = gson.create().toJson(syncItems);

        mBackendFacade = (BackendFacade) new BackendFacade(endpoint, this, json);
        mBackendFacade.execute();
        return null;
    }
}