Weather API: Delegate the responsability of rejecting back to back requests [1/2]

The Weather Manager Service should not impose rules regarding how
a weather provide service wants to react to back to back weather
update requests, nor impose the time a caller should wait before
a new request can be submitted. These constraints vary between
weather services, so it's up the each implementation to enforce
these constraints.

With this patch, the Weather manager service will pass the requests
as they come from the requester and it will be up to the active service
provider decide whether process or reject the request.

Changes to API:
- Moved the request statuses to new inner class RequestStatus in
 CMWeatherManager
- Pass status arg to onLookupCityRequestCompleted()
- Added reject(int) method to ServiceRequest

Change-Id: I3512490688255e25395e955d506fe42ed52f8fe0
TICKET: CYNGNOS-2430

3 files changed, 120 insertions, 90 deletions

diff --git a/sdk/src/java/cyanogenmod/weather/CMWeatherManager.java b/sdk/src/java/cyanogenmod/weather/CMWeatherManager.java
index 545c3ce..8292b58 100644
--- a/sdk/src/java/cyanogenmod/weather/CMWeatherManager.java
+++ b/sdk/src/java/cyanogenmod/weather/CMWeatherManager.java
@@ -53,40 +53,32 @@ public class CMWeatherManager {
 
     private static final String TAG = CMWeatherManager.class.getSimpleName();
 
-    /**
-     * Weather update request state: Successfully completed
-     */
-    public static final int WEATHER_REQUEST_COMPLETED = 1;
-
-    /**
-     * Weather update request state: You need to wait a bit longer before requesting an update
-     * again.
-     * <p>Please bear in mind that the weather does not change very often. A threshold of 10 minutes
-     * is enforced by the system</p>
-     */
-    public static final int WEATHER_REQUEST_SUBMITTED_TOO_SOON = -1;
-
-    /**
-     * Weather update request state: An error occurred while trying to update the weather. You
-     * should wait before trying again, or your request will be rejected with
-     * {@link #WEATHER_REQUEST_SUBMITTED_TOO_SOON}
-     */
-    public static final int WEATHER_REQUEST_FAILED = -2;
 
     /**
-     * Weather update request state: Only one update request can be processed at a given time.
+     * The different request statuses
      */
-    public static final int WEATHER_REQUEST_ALREADY_IN_PROGRESS = -3;
-
-    /** @hide */
-    public static final int LOOKUP_REQUEST_COMPLETED  = 100;
-
-    /** @hide */
-    public static final int LOOKUP_REQUEST_FAILED = -100;
-
-    /** @hide */
-    public static final int LOOKUP_REQUEST_NO_MATCH_FOUND = -101;
-
+    public static class RequestStatus {
+        /**
+         * Request Successfully completed
+         */
+        public static final int COMPLETED = 1;
+        /**
+         * An error occurred while trying to honor the request.
+         */
+        public static final int FAILED = -1;
+        /**
+         * The request can't be processed at this time
+         */
+        public static final int SUBMITTED_TOO_SOON = -2;
+        /**
+         * Another request in already in progress
+         */
+        public static final int ALREADY_IN_PROGRESS = -3;
+        /**
+         * No match found for the query
+         */
+        public static final int NO_MATCH_FOUND = -4;
+    }
 
     private CMWeatherManager(Context context) {
         Context appContext = context.getApplicationContext();
@@ -330,7 +322,7 @@ public class CMWeatherManager {
     private final IRequestInfoListener mRequestInfoListener = new IRequestInfoListener.Stub() {
 
         @Override
-        public void onWeatherRequestCompleted(final RequestInfo requestInfo, final int state,
+        public void onWeatherRequestCompleted(final RequestInfo requestInfo, final int status,
                 final WeatherInfo weatherInfo) {
             final WeatherUpdateRequestListener listener
                     = mWeatherUpdateRequestListeners.remove(requestInfo);
@@ -338,14 +330,14 @@ public class CMWeatherManager {
                 mHandler.post(new Runnable() {
                     @Override
                     public void run() {
-                        listener.onWeatherRequestCompleted(state, weatherInfo);
+                        listener.onWeatherRequestCompleted(status, weatherInfo);
                     }
                 });
             }
         }
 
         @Override
-        public void onLookupCityRequestCompleted(RequestInfo requestInfo,
+        public void onLookupCityRequestCompleted(RequestInfo requestInfo, final int status,
             final List<WeatherLocation> weatherLocations) {
 
             final LookupCityRequestListener listener
@@ -354,7 +346,7 @@ public class CMWeatherManager {
                 mHandler.post(new Runnable() {
                     @Override
                     public void run() {
-                        listener.onLookupCityRequestCompleted(weatherLocations);
+                        listener.onLookupCityRequestCompleted(status, weatherLocations);
                     }
                 });
             }
@@ -369,16 +361,12 @@ public class CMWeatherManager {
          * This method will be called when the weather service provider has finished processing the
          * request
          *
-         * @param state Any of the following values
-         *              {@link #WEATHER_REQUEST_COMPLETED}
-         *              {@link #WEATHER_REQUEST_ALREADY_IN_PROGRESS}
-         *              {@link #WEATHER_REQUEST_SUBMITTED_TOO_SOON}
-         *              {@link #WEATHER_REQUEST_FAILED}
+         * @param status See {@link RequestStatus}
          *
          * @param weatherInfo A fully populated {@link WeatherInfo} if state is
-         *                    {@link #WEATHER_REQUEST_COMPLETED}, null otherwise
+         *                    {@link RequestStatus#COMPLETED}, null otherwise
          */
-        void onWeatherRequestCompleted(int state, WeatherInfo weatherInfo);
+        void onWeatherRequestCompleted(int status, WeatherInfo weatherInfo);
     }
 
     /**
@@ -387,11 +375,14 @@ public class CMWeatherManager {
     public interface LookupCityRequestListener {
         /**
          * This method will be called when the weather service provider has finished processing the
-         * request. The argument can be null if the provider couldn't find a match
+         * request.
+         *
+         * @param status See {@link RequestStatus}
          *
-         * @param locations
+         * @param locations A list of {@link WeatherLocation} if the status is
+         * {@link RequestStatus#COMPLETED}, null otherwise
          */
-        void onLookupCityRequestCompleted(List<WeatherLocation> locations);
+        void onLookupCityRequestCompleted(int status, List<WeatherLocation> locations);
     }
 
     /**
diff --git a/sdk/src/java/cyanogenmod/weather/IRequestInfoListener.aidl b/sdk/src/java/cyanogenmod/weather/IRequestInfoListener.aidl
index 553da71..d35db44 100644
--- a/sdk/src/java/cyanogenmod/weather/IRequestInfoListener.aidl
+++ b/sdk/src/java/cyanogenmod/weather/IRequestInfoListener.aidl
@@ -24,8 +24,8 @@ import java.util.List;
 
 /** @hide */
 oneway interface IRequestInfoListener {
-    void onWeatherRequestCompleted(in RequestInfo requestInfo, int state,
+    void onWeatherRequestCompleted(in RequestInfo requestInfo, int status,
         in WeatherInfo weatherInfo);
-    void onLookupCityRequestCompleted(in RequestInfo requestInfo,
+    void onLookupCityRequestCompleted(in RequestInfo requestInfo, int status,
         in List<WeatherLocation> weatherLocation);
 }
\ No newline at end of file
diff --git a/sdk/src/java/cyanogenmod/weatherservice/ServiceRequest.java b/sdk/src/java/cyanogenmod/weatherservice/ServiceRequest.java
index bc2f38d..f503a2f 100644
--- a/sdk/src/java/cyanogenmod/weatherservice/ServiceRequest.java
+++ b/sdk/src/java/cyanogenmod/weatherservice/ServiceRequest.java
@@ -29,15 +29,15 @@ public final class ServiceRequest {
     private final RequestInfo mInfo;
     private final IWeatherProviderServiceClient mClient;
 
-    /**
-     * If a request is marked as cancelled, it means the client does not want to know anything about
-     * this request anymore
-     */
-    private volatile boolean mCancelled;
+    private enum Status {
+        IN_PROGRESS, COMPLETED, CANCELLED, FAILED, REJECTED
+    }
+    private Status mStatus;
 
     /* package */ ServiceRequest(RequestInfo info, IWeatherProviderServiceClient client) {
         mInfo = info;
         mClient = client;
+        mStatus = Status.IN_PROGRESS;
     }
 
     /**
@@ -52,32 +52,36 @@ public final class ServiceRequest {
      * This method should be called once the request has been completed
      */
     public void complete(@NonNull ServiceRequestResult result) {
-        if (!mCancelled) {
-            try {
-                final int requestType = mInfo.getRequestType();
-                switch (requestType) {
-                    case RequestInfo.TYPE_WEATHER_BY_GEO_LOCATION_REQ:
-                    case RequestInfo.TYPE_WEATHER_BY_WEATHER_LOCATION_REQ:
-                        if (result.getWeatherInfo() == null) {
-                            throw new IllegalStateException("The service request result does not"
-                             + " contain a valid WeatherInfo object");
-                        }
-                        mClient.setServiceRequestState(mInfo, result,
-                                CMWeatherManager.WEATHER_REQUEST_COMPLETED);
-                        break;
-                    case RequestInfo.TYPE_LOOKUP_CITY_NAME_REQ:
-                        if (result.getLocationLookupList() == null) {
-                            //In case the user decided to mark this request as completed with an
-                            //empty list. It's not necessarily a failure
-                            mClient.setServiceRequestState(mInfo, null,
-                                    CMWeatherManager.LOOKUP_REQUEST_NO_MATCH_FOUND);
-                        } else {
+        synchronized (this) {
+            if (mStatus.equals(Status.IN_PROGRESS)) {
+                try {
+                    final int requestType = mInfo.getRequestType();
+                    switch (requestType) {
+                        case RequestInfo.TYPE_WEATHER_BY_GEO_LOCATION_REQ:
+                        case RequestInfo.TYPE_WEATHER_BY_WEATHER_LOCATION_REQ:
+                            if (result.getWeatherInfo() == null) {
+                                throw new IllegalStateException("The service request result doesn't"
+                                        + " contain a valid WeatherInfo object");
+                            }
                             mClient.setServiceRequestState(mInfo, result,
-                                    CMWeatherManager.LOOKUP_REQUEST_COMPLETED);
-                        }
-                        break;
+                                    CMWeatherManager.RequestStatus.COMPLETED);
+                            break;
+                        case RequestInfo.TYPE_LOOKUP_CITY_NAME_REQ:
+                            if (result.getLocationLookupList() == null
+                                    || result.getLocationLookupList().size() <= 0) {
+                                //In case the user decided to mark this request as completed with
+                                //null or empty list. It's not necessarily a failure
+                                mClient.setServiceRequestState(mInfo, null,
+                                        CMWeatherManager.RequestStatus.NO_MATCH_FOUND);
+                            } else {
+                                mClient.setServiceRequestState(mInfo, result,
+                                        CMWeatherManager.RequestStatus.COMPLETED);
+                            }
+                            break;
+                    }
+                } catch (RemoteException e) {
                 }
-            } catch (RemoteException e) {
+                mStatus = Status.COMPLETED;
             }
         }
     }
@@ -87,21 +91,54 @@ public final class ServiceRequest {
      * (no internet connection, time out, etc.)
      */
     public void fail() {
-        if (!mCancelled) {
-            try {
-                final int requestType = mInfo.getRequestType();
-                switch (requestType) {
-                    case RequestInfo.TYPE_WEATHER_BY_GEO_LOCATION_REQ:
-                    case RequestInfo.TYPE_WEATHER_BY_WEATHER_LOCATION_REQ:
-                        mClient.setServiceRequestState(mInfo, null,
-                                CMWeatherManager.WEATHER_REQUEST_FAILED);
-                        break;
-                    case RequestInfo.TYPE_LOOKUP_CITY_NAME_REQ:
-                        mClient.setServiceRequestState(mInfo, null,
-                                CMWeatherManager.LOOKUP_REQUEST_FAILED);
+        synchronized (this) {
+            if (mStatus.equals(Status.IN_PROGRESS)) {
+                try {
+                    final int requestType = mInfo.getRequestType();
+                    switch (requestType) {
+                        case RequestInfo.TYPE_WEATHER_BY_GEO_LOCATION_REQ:
+                        case RequestInfo.TYPE_WEATHER_BY_WEATHER_LOCATION_REQ:
+                            mClient.setServiceRequestState(mInfo, null,
+                                    CMWeatherManager.RequestStatus.FAILED);
+                            break;
+                        case RequestInfo.TYPE_LOOKUP_CITY_NAME_REQ:
+                            mClient.setServiceRequestState(mInfo, null,
+                                    CMWeatherManager.RequestStatus.FAILED);
+                            break;
+                    }
+                } catch (RemoteException e) {
+                }
+                mStatus = Status.FAILED;
+            }
+        }
+    }
+
+    /**
+     * This method should be called if the service decides not to honor the request. Note this
+     * method will accept only the following values.
+     * <ul>
+     * <li>{@link cyanogenmod.weather.CMWeatherManager.RequestStatus#SUBMITTED_TOO_SOON}</li>
+     * <li>{@link cyanogenmod.weather.CMWeatherManager.RequestStatus#ALREADY_IN_PROGRESS}</li>
+     * </ul>
+     * Attempting to pass any other value will get you an IllegalArgumentException
+     * @param status
+     */
+    public void reject(int status) {
+        synchronized (this) {
+            if (mStatus.equals(Status.IN_PROGRESS)) {
+                switch (status) {
+                    case CMWeatherManager.RequestStatus.ALREADY_IN_PROGRESS:
+                    case CMWeatherManager.RequestStatus.SUBMITTED_TOO_SOON:
+                        try {
+                            mClient.setServiceRequestState(mInfo, null, status);
+                        } catch (RemoteException e) {
+                            e.printStackTrace();
+                        }
                         break;
+                    default:
+                        throw new IllegalArgumentException("Can't reject with status " + status);
                 }
-            } catch (RemoteException e) {
+                mStatus = Status.REJECTED;
             }
         }
     }
@@ -113,6 +150,8 @@ public final class ServiceRequest {
      * @hide
      */
     public void cancel() {
-        mCancelled = true;
+        synchronized (this) {
+            mStatus = Status.CANCELLED;
+        }
     }
 }