/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.sling.jcr.repoinit.impl;

import java.util.concurrent.atomic.AtomicInteger;
import java.util.function.Supplier;

import org.junit.Test;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertTrue;

public class RetryableOperationTest {

    @Test
    public void testWithoutRetry() {

        RetryableOperation ro = new RetryableOperation.Builder().build();
        Supplier<RetryableOperation.RetryableOperationResult> op = () -> {
            return new RetryableOperation.RetryableOperationResult(true, false, null, null);
        };
        RetryableOperation.RetryableOperationResult result = ro.apply(op, "log");
        assertEquals(0, ro.retryCount);
        assertTrue(result.isSuccessful());
    }

    @Test
    public void testWithRetrySuccesful() {

        // bypass the effective final feature
        AtomicInteger retries = new AtomicInteger(0);
        RetryableOperation ro = new RetryableOperation.Builder()
                .withBackoffBaseMsec(10)
                .withMaxRetries(3)
                .build();
        Supplier<RetryableOperation.RetryableOperationResult> op = () -> {
            // 1 regular execution + 2 retries
            if (retries.getAndAdd(1) == 2) {
                return new RetryableOperation.RetryableOperationResult(true, false, null, null);
            } else {
                return new RetryableOperation.RetryableOperationResult(false, true, null, new RuntimeException());
            }
        };
        RetryableOperation.RetryableOperationResult result = ro.apply(op, "log");
        assertEquals(2, ro.retryCount);
        assertTrue(result.isSuccessful());
    }

    @Test
    public void testWithRetryFail() {

        AtomicInteger retries = new AtomicInteger(0);
        RetryableOperation ro = new RetryableOperation.Builder()
                .withBackoffBaseMsec(10)
                .withMaxRetries(3)
                .withJitterMsec(10)
                .build();
        Supplier<RetryableOperation.RetryableOperationResult> op = () -> {
            // 1 regular execution + 4 retries
            if (retries.getAndAdd(1) == 4) {
                return new RetryableOperation.RetryableOperationResult(true, false, null, null);
            } else {
                return new RetryableOperation.RetryableOperationResult(false, true, null, new RuntimeException());
            }
        };
        RetryableOperation.RetryableOperationResult result = ro.apply(op, "log");
        assertEquals(3, ro.retryCount); // only 3 retries and then stopped
        assertFalse(result.isSuccessful());
        assertNotNull(result.getFailureTrace());
    }

    @Test
    public void testWithPermanentFailure() {

        RetryableOperation ro = new RetryableOperation.Builder()
                .withBackoffBaseMsec(10)
                .withMaxRetries(3)
                .build();
        Supplier<RetryableOperation.RetryableOperationResult> op = () -> {
            // indicate a permanent failure, where it doesn't make sense to retry
            return new RetryableOperation.RetryableOperationResult(false, false, null, new RuntimeException());
        };
        RetryableOperation.RetryableOperationResult result = ro.apply(op, "log");
        assertEquals(0, ro.retryCount); // no retry
        assertFalse(result.isSuccessful());
    }
}