/**
 * Copyright 2014 Netflix, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package rx.android.subscriptions;

import rx.Scheduler.Inner;
import rx.Subscription;
import rx.android.schedulers.AndroidSchedulers;
import rx.functions.Action0;
import rx.functions.Action1;
import rx.subscriptions.Subscriptions;
import android.os.Looper;

public final class AndroidSubscriptions {

    private AndroidSubscriptions() {
        // no instance
    }

    /**
     * Create an Subscription that always runs <code>unsubscribe</code> in the UI thread.
     * 
     * @param unsubscribe
     * @return an Subscription that always runs <code>unsubscribe</code> in the UI thread.
     */
    public static Subscription unsubscribeInUiThread(final Action0 unsubscribe) {
        return Subscriptions.create(new Action0() {
            @Override
            public void call() {
                if (Looper.getMainLooper() == Looper.myLooper()) {
                    unsubscribe.call();
                } else {
                    AndroidSchedulers.mainThread().schedule(new Action1<Inner>() {
                        @Override
                        public void call(Inner inner) {
                            unsubscribe.call();
                        }
                    });
                }
            }
        });
    }
}
