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.sync;
michael@0: 
michael@0: import java.util.Collections;
michael@0: import java.util.HashMap;
michael@0: import java.util.Map;
michael@0: import java.util.Map.Entry;
michael@0: 
michael@0: import org.mozilla.gecko.background.common.log.Logger;
michael@0: 
michael@0: /**
michael@0:  * Fetches the timestamp information in <code>info/collections</code> on the
michael@0:  * Sync server. Provides access to those timestamps, along with logic to check
michael@0:  * for whether a collection requires an update.
michael@0:  */
michael@0: public class InfoCollections {
michael@0:   private static final String LOG_TAG = "InfoCollections";
michael@0: 
michael@0:   /**
michael@0:    * Fields fetched from the server, or <code>null</code> if not yet fetched.
michael@0:    * <p>
michael@0:    * Rather than storing decimal/double timestamps, as provided by the server,
michael@0:    * we convert immediately to milliseconds since epoch.
michael@0:    */
michael@0:   final Map<String, Long> timestamps;
michael@0: 
michael@0:   public InfoCollections() {
michael@0:     this(new ExtendedJSONObject());
michael@0:   }
michael@0: 
michael@0:   public InfoCollections(final ExtendedJSONObject record) {
michael@0:     Logger.debug(LOG_TAG, "info/collections is " + record.toJSONString());
michael@0:     HashMap<String, Long> map = new HashMap<String, Long>();
michael@0: 
michael@0:     for (Entry<String, Object> entry : record.entrySet()) {
michael@0:       final String key = entry.getKey();
michael@0:       final Object value = entry.getValue();
michael@0: 
michael@0:       // These objects are most likely going to be Doubles. Regardless, we
michael@0:       // want to get them in a more sane time format.
michael@0:       if (value instanceof Double) {
michael@0:         map.put(key, Utils.decimalSecondsToMilliseconds((Double) value));
michael@0:         continue;
michael@0:       }
michael@0:       if (value instanceof Long) {
michael@0:         map.put(key, Utils.decimalSecondsToMilliseconds((Long) value));
michael@0:         continue;
michael@0:       }
michael@0:       if (value instanceof Integer) {
michael@0:         map.put(key, Utils.decimalSecondsToMilliseconds((Integer) value));
michael@0:         continue;
michael@0:       }
michael@0:       Logger.warn(LOG_TAG, "Skipping info/collections entry for " + key);
michael@0:     }
michael@0: 
michael@0:     this.timestamps = Collections.unmodifiableMap(map);
michael@0:   }
michael@0: 
michael@0:   /**
michael@0:    * Return the timestamp for the given collection, or null if the timestamps
michael@0:    * have not been fetched or the given collection does not have a timestamp.
michael@0:    *
michael@0:    * @param collection
michael@0:    *          The collection to inspect.
michael@0:    * @return the timestamp in milliseconds since epoch.
michael@0:    */
michael@0:   public Long getTimestamp(String collection) {
michael@0:     if (timestamps == null) {
michael@0:       return null;
michael@0:     }
michael@0:     return timestamps.get(collection);
michael@0:   }
michael@0: 
michael@0:   /**
michael@0:    * Test if a given collection needs to be updated.
michael@0:    *
michael@0:    * @param collection
michael@0:    *          The collection to test.
michael@0:    * @param lastModified
michael@0:    *          Timestamp when local record was last modified.
michael@0:    */
michael@0:   public boolean updateNeeded(String collection, long lastModified) {
michael@0:     Logger.trace(LOG_TAG, "Testing " + collection + " for updateNeeded. Local last modified is " + lastModified + ".");
michael@0: 
michael@0:     // No local record of modification time? Need an update.
michael@0:     if (lastModified <= 0) {
michael@0:       return true;
michael@0:     }
michael@0: 
michael@0:     // No meta/global on the server? We need an update. The server fetch will fail and
michael@0:     // then we will upload a fresh meta/global.
michael@0:     Long serverLastModified = getTimestamp(collection);
michael@0:     if (serverLastModified == null) {
michael@0:       return true;
michael@0:     }
michael@0: 
michael@0:     // Otherwise, we need an update if our modification time is stale.
michael@0:     return (serverLastModified.longValue() > lastModified);
michael@0:   }
michael@0: }