/*
 * Copyright (c) "Neo4j"
 * Neo4j Sweden AB [http://neo4j.com]
 *
 * This file is part of Neo4j.
 *
 * Neo4j is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.neo4j.configuration.pagecache;

import static org.assertj.core.api.Assertions.assertThat;
import static org.junit.jupiter.api.Assertions.assertFalse;
import static org.neo4j.configuration.GraphDatabaseSettings.pagecache_buffered_flush_enabled;
import static org.neo4j.memory.EmptyMemoryTracker.INSTANCE;

import org.junit.jupiter.api.Test;
import org.neo4j.configuration.Config;
import org.neo4j.memory.ScopedMemoryTracker;

class ConfigurableIOBufferFactoryTest {
    @Test
    void createDisabledBufferCanBeDisabled() {
        var config = Config.defaults(pagecache_buffered_flush_enabled, false);
        var bufferFactory = new ConfigurableIOBufferFactory(config, INSTANCE);
        try (var ioBuffer = bufferFactory.createBuffer()) {
            assertFalse(ioBuffer.isEnabled());
        }
    }

    @Test
    void disabledBufferDoesNotConsumeMemory() {
        var config = Config.defaults(pagecache_buffered_flush_enabled, false);
        var memoryTracker = new ScopedMemoryTracker(INSTANCE);
        var bufferFactory = new ConfigurableIOBufferFactory(config, INSTANCE);
        try (var ioBuffer = bufferFactory.createBuffer()) {
            assertFalse(ioBuffer.isEnabled());
            assertThat(memoryTracker.usedNativeMemory()).isZero();
        }
    }

    @Test
    void defaultBufferCreation() {
        var config = Config.defaults();
        var memoryTracker = new ScopedMemoryTracker(INSTANCE);
        var bufferFactory = new ConfigurableIOBufferFactory(config, memoryTracker);
        try (var ioBuffer = bufferFactory.createBuffer()) {
            assertFalse(ioBuffer.isEnabled());
            assertThat(memoryTracker.usedNativeMemory()).isZero();
        }
        assertThat(memoryTracker.usedNativeMemory()).isZero();
    }
}
