/*
 * SPDX-License-Identifier: Apache-2.0
 *
 * The OpenSearch Contributors require contributions made to
 * this file be licensed under the Apache-2.0 license or a
 * compatible open source license.
 */

/*
 * Licensed to Elasticsearch under one or more contributor
 * license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright
 * ownership. Elasticsearch 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.
 */

/*
 * Modifications Copyright OpenSearch Contributors. See
 * GitHub history for details.
 */

package org.opensearch.node;

import org.opensearch.cluster.ClusterName;
import org.opensearch.common.settings.MockSecureSettings;
import org.opensearch.common.settings.SecureSetting;
import org.opensearch.common.settings.Setting;
import org.opensearch.common.settings.Settings;
import org.opensearch.common.settings.SettingsException;
import org.opensearch.core.common.settings.SecureString;
import org.opensearch.env.Environment;
import org.opensearch.test.OpenSearchTestCase;
import org.junit.After;
import org.junit.Before;

import java.io.IOException;
import java.io.InputStream;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.Collections;
import java.util.Map;
import java.util.function.Supplier;

import static java.util.Collections.emptyMap;

public class InternalSettingsPreparerTests extends OpenSearchTestCase {
    private static final Supplier<String> DEFAULT_NODE_NAME_SHOULDNT_BE_CALLED = () -> { throw new AssertionError("shouldn't be called"); };

    Path homeDir;
    Settings baseEnvSettings;

    @Before
    public void createBaseEnvSettings() {
        homeDir = createTempDir();
        baseEnvSettings = Settings.builder().put(Environment.PATH_HOME_SETTING.getKey(), homeDir).build();
    }

    @After
    public void clearBaseEnvSettings() {
        homeDir = null;
        baseEnvSettings = null;
    }

    public void testEmptySettings() {
        Settings settings = InternalSettingsPreparer.prepareSettings(Settings.EMPTY);
        assertNull(settings.get("node.name"));
        assertNotNull(settings.get(ClusterName.CLUSTER_NAME_SETTING.getKey())); // a cluster name was set
        int size = settings.names().size();

        String defaultNodeName = randomAlphaOfLength(8);
        Environment env = InternalSettingsPreparer.prepareEnvironment(baseEnvSettings, emptyMap(), null, () -> defaultNodeName);
        settings = env.settings();
        assertEquals(defaultNodeName, settings.get("node.name"));
        assertNotNull(settings.get(ClusterName.CLUSTER_NAME_SETTING.getKey())); // a cluster name was set
        assertEquals(settings.toString(), size + 1 /* path.home is in the base settings */, settings.names().size());
        String home = Environment.PATH_HOME_SETTING.get(baseEnvSettings);
        String configDir = env.configDir().toString();
        assertTrue(configDir, configDir.startsWith(home));
    }

    public void testDefaultClusterName() {
        Settings settings = InternalSettingsPreparer.prepareSettings(Settings.EMPTY);
        assertEquals("opensearch", settings.get("cluster.name"));
        settings = InternalSettingsPreparer.prepareSettings(Settings.builder().put("cluster.name", "foobar").build());
        assertEquals("foobar", settings.get("cluster.name"));
    }

    public void testGarbageIsNotSwallowed() throws IOException {
        try {
            InputStream garbage = getClass().getResourceAsStream("/config/garbage/garbage.yml");
            Path home = createTempDir();
            Path config = home.resolve("config");
            Files.createDirectory(config);
            Files.copy(garbage, config.resolve("opensearch.yml"));
            InternalSettingsPreparer.prepareEnvironment(
                Settings.builder().put(baseEnvSettings).build(),
                emptyMap(),
                null,
                () -> "default_node_name"
            );
        } catch (SettingsException e) {
            assertEquals("Failed to load settings from [opensearch.yml]", e.getMessage());
        }
    }

    public void testSecureSettings() {
        MockSecureSettings secureSettings = new MockSecureSettings();
        secureSettings.setString("foo", "secret");
        Settings input = Settings.builder().put(baseEnvSettings).setSecureSettings(secureSettings).build();
        Environment env = InternalSettingsPreparer.prepareEnvironment(input, emptyMap(), null, () -> "default_node_name");
        Setting<SecureString> fakeSetting = SecureSetting.secureString("foo", null);
        assertEquals("secret", fakeSetting.get(env.settings()).toString());
    }

    public void testDefaultPropertiesDoNothing() throws Exception {
        Map<String, String> props = Collections.singletonMap("default.setting", "foo");
        Environment env = InternalSettingsPreparer.prepareEnvironment(baseEnvSettings, props, null, () -> "default_node_name");
        assertEquals("foo", env.settings().get("default.setting"));
        assertNull(env.settings().get("setting"));
    }

}
