/*
 * Copyright (C) 2010 The Android Open Source Project
 *
 * 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 com.google.android.vending.licensing;

/**
 * Callback for the license checker library.
 * <p/>
 * Upon checking with the Market server and conferring with the {@link com.google.android.vending
 * .licensing.Policy},
 * the library calls the appropriate callback method to communicate the result.
 * <p/>
 * <b>The callback does not occur in the original checking thread.</b> Your
 * application should post to the appropriate handling thread or lock
 * accordingly.
 * <p/>
 * The reason that is passed back with allow/dontAllow is the base status handed
 * to the policy for allowed/disallowing the license. Policy.RETRY will call
 * allow or dontAllow depending on other statistics associated with the policy,
 * while in most cases Policy.NOT_LICENSED will call dontAllow and
 * Policy.LICENSED will Allow.
 */
public interface LicenseCheckerCallback {

    /**
     * Application error codes.
     */

    /**
     * Allow use. App should proceed as normal.
     *
     * @param reason Policy.LICENSED or Policy.RETRY typically. (although in
     * theory the policy can return Policy.NOT_LICENSED here as well)
     */
    void allow(int reason);

    /**
     * Don't allow use. App should inform user and take appropriate action.
     *
     * @param reason Policy.NOT_LICENSED or Policy.RETRY. (although in theory
     * the policy can return Policy.LICENSED here as well ---
     * perhaps the call to the LVL took too long, for example)
     */
    void dontAllow(int reason);

    /**
     * Error in application code. Caller did not call or set up license checker
     * correctly. Should be considered fatal.
     */
    void applicationError(int errorCode);
}