// Copyright 2019 The Nomulus Authors. All Rights Reserved.
//
// 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 google.registry.testing;

import static google.registry.testing.JUnitBackports.assertThrows;
import static java.nio.charset.StandardCharsets.UTF_8;

import com.google.common.base.Joiner;
import java.io.File;
import java.io.IOException;
import org.junit.Before;
import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.TemporaryFolder;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

/**
 * Unit tests for {@link google.registry.testing.AppEngineRule}. Tests focus on Datastoe-related
 * assertions made during teardown checks.
 */
@RunWith(JUnit4.class)
public class AppEngineRuleTest {

  // An arbitrary index in google/registry/env/common/default/WEB-INF/datastore-indexes.xml
  private static final String DECLARED_INDEX =
      Joiner.on('\n')
          .join(
              "<datastore-indexes autoGenerate=\"false\">",
              "  <datastore-index kind=\"ContactResource\" ancestor=\"false\" source=\"manual\">",
              "    <property name=\"currentSponsorClientId\" direction=\"asc\"/>",
              "    <property name=\"deletionTime\" direction=\"asc\"/>",
              "    <property name=\"searchName\" direction=\"asc\"/>",
              "  </datastore-index>",
              "</datastore-indexes>");
  private static final String UNDECLARED_INDEX =
      DECLARED_INDEX.replace("ContactResource", "NoSuchResource");

  @Rule public TemporaryFolder temporaryFolder = new TemporaryFolder();

  private final AppEngineRule appEngineRule = AppEngineRule.builder().withDatastore().build();

  @Before
  public void setupAppEngineRule() throws Exception {
    appEngineRule.temporaryFolder = temporaryFolder;
    appEngineRule.before();
  }

  @Test
  public void testTeardown_successNoAutoIndexFile() {
    appEngineRule.after();
  }

  @Test
  public void testTeardown_successEmptyAutoIndexFile() throws Exception {
    writeAutoIndexFile("");
    appEngineRule.after();
  }

  @Test
  public void testTeardown_successWhiteSpacesOnlyAutoIndexFile() throws Exception {
    writeAutoIndexFile("  ");
    appEngineRule.after();
  }

  @Test
  public void testTeardown_successOnlyDeclaredIndexesUsed() throws Exception {
    writeAutoIndexFile(DECLARED_INDEX);
    appEngineRule.after();
  }

  @Test
  public void testTeardown_failureUndeclaredIndexesUsed() throws Exception {
    writeAutoIndexFile(UNDECLARED_INDEX);
    assertThrows(AssertionError.class, () -> appEngineRule.after());
  }

  private void writeAutoIndexFile(String content) throws IOException {
    com.google.common.io.Files.asCharSink(
            new File(temporaryFolder.getRoot(), "datastore-indexes-auto.xml"), UTF_8)
        .write(content);
  }
}