/*
 * Copyright (c) 2016 Couchbase, 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 com.couchbase.client.core.service.strategies;

import com.couchbase.client.core.endpoint.Endpoint;
import com.couchbase.client.core.message.CouchbaseRequest;
import com.couchbase.client.core.state.LifecycleState;
import org.junit.Test;

import java.util.Arrays;
import java.util.Collections;
import java.util.List;

import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertNull;
import static org.junit.Assert.assertTrue;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.when;

/**
 * Verifies the functionality of the {@link RandomSelectionStrategy}.
 *
 * @author Michael Nitschinger
 * @since 1.0
 */
public class RandomSelectionStrategyTest {

    @Test
    public void shouldSelectEndpoint() {
        SelectionStrategy strategy = new RandomSelectionStrategy();

        Endpoint endpoint1 = mock(Endpoint.class);
        when(endpoint1.isState(LifecycleState.CONNECTED)).thenReturn(true);
        when(endpoint1.isFree()).thenReturn(true);
        Endpoint endpoint2 = mock(Endpoint.class);
        when(endpoint2.isState(LifecycleState.CONNECTED)).thenReturn(false);
        when(endpoint2.isFree()).thenReturn(true);
        Endpoint endpoint3 = mock(Endpoint.class);
        when(endpoint3.isState(LifecycleState.CONNECTED)).thenReturn(true);
        when(endpoint3.isFree()).thenReturn(true);
        List<Endpoint> endpoints = Arrays.asList(endpoint1, endpoint2, endpoint3);

        for (int i = 0; i < 1000; i++) {
            Endpoint selected = strategy.select(mock(CouchbaseRequest.class), endpoints);
            assertNotNull(selected);
            assertFalse(selected.equals(endpoint2));
            assertTrue(selected.equals(endpoint1) || selected.equals(endpoint3));
        }
    }

    @Test
    public void shouldReturnIfEmptyArrayPassedIn() {
        SelectionStrategy strategy = new RandomSelectionStrategy();

        Endpoint selected = strategy.select(mock(CouchbaseRequest.class), Collections.<Endpoint>emptyList());
        assertNull(selected);
    }
}