// Copyright (c) 2019, the R8 project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

package backport;

import com.android.tools.r8.TestBase;
import com.android.tools.r8.TestParameters;
import com.android.tools.r8.TestRuntime.CfVm;
import com.android.tools.r8.desugar.backports.AbstractBackportTest;
import com.android.tools.r8.desugar.backports.IgnoreInvokes;
import com.android.tools.r8.utils.AndroidApiLevel;
import java.util.Objects;
import org.hamcrest.CoreMatchers;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameters;

@RunWith(Parameterized.class)
public final class ObjectsBackportJava9Test extends AbstractBackportTest {
  @Parameters(name = "{0}")
  public static Iterable<?> data() {
    return TestBase.getTestParameters()
        .withDexRuntimes()
        .withCfRuntimesStartingFromIncluding(CfVm.JDK9)
        .withAllApiLevelsAlsoForCf()
        .build();
  }

  public ObjectsBackportJava9Test(TestParameters parameters) {
    super(parameters, Objects.class, ObjectsBackportJava9Main.class);
    // Objects.checkFromIndexSize, Objects.checkFromToIndex, Objects.checkIndex,
    // Objects.requireNonNullElse and Objects.requireNonNullElseGet added in API 30.
    registerTarget(AndroidApiLevel.R, 28);
    registerTarget(AndroidApiLevel.N, 0);
    // Objects.requireNonNullElseGet is not desugared if Supplier is absent.
    registerTarget(AndroidApiLevel.B, 4);
  }

  @Test
  public void desugaringApiLevelR() throws Exception {
    // TODO(b/154759404): This test should start to fail when testing on an Android R VM.
    // This has now been checked with S, when R testing is added chck and remove this.
    if (parameters.getRuntime().isDex() && parameters.getApiLevel().isEqualTo(AndroidApiLevel.R)) {
      testForD8()
          .setMinApi(AndroidApiLevel.R)
          .addProgramClasses(MiniAssert.class, IgnoreInvokes.class)
          .addProgramClasses(ObjectsBackportJava9Main.class)
          .setIncludeClassesChecksum(true)
          .compile()
          .run(parameters.getRuntime(), ObjectsBackportJava9Main.class)
          .assertFailureWithErrorThatMatches(
              CoreMatchers.containsString("java.lang.NoSuchMethodError"));
    }
  }

  public static class ObjectsBackportJava9Main {
    public static void main(String[] args) {
      boolean isAndroid = "Dalvik".equals(System.getProperty("java.vm.name"));
      String majorVersion = System.getProperty("java.vm.version").split("\\.", -1)[0];

      testRequireNonNullElse();
      if (!isAndroid || Integer.parseInt(majorVersion) >= 7) {
        // TODO desugaring desugaredlibrary is blocked by
        // https://issuetracker.google.com/issues/114481425
        testRequireNonNullElseGet();
      }
      testCheckIndex();
      testCheckFromToIndex();
      testCheckFromIndexSize();
    }

    private static void testRequireNonNullElse() {
      Object one = new Object();
      Object two = new Object();

      assertSame(one, Objects.requireNonNullElse(one, two));
      assertSame(two, Objects.requireNonNullElse(null, two));

      try {
        throw new AssertionError(Objects.requireNonNullElse(null, null));
      } catch (NullPointerException expected) {
      }
    }

    private static void testRequireNonNullElseGet() {
      Object one = new Object();
      Object two = new Object();

      assertSame(one, Objects.requireNonNullElseGet(one, () -> two));
      assertSame(two, Objects.requireNonNullElseGet(null, () -> two));

      try {
        throw new AssertionError(Objects.requireNonNullElseGet(null, null));
      } catch (NullPointerException expected) {
      }
      try {
        throw new AssertionError(Objects.requireNonNullElseGet(null, () -> null));
      } catch (NullPointerException expected) {
      }
    }

    private static void testCheckIndex() {
      for (int i = 0; i < 10; i++) {
        assertEquals(i, Objects.checkIndex(i, 10));
      }

      try {
        throw new AssertionError(Objects.checkIndex(-1, 10));
      } catch (IndexOutOfBoundsException expected) {
      }
      try {
        throw new AssertionError(Objects.checkIndex(10, 0));
      } catch (IndexOutOfBoundsException expected) {
      }
      try {
        throw new AssertionError(Objects.checkIndex(0, 0));
      } catch (IndexOutOfBoundsException expected) {
      }
    }

    private static void testCheckFromToIndex() {
      for (int i = 0; i <= 10; i++) {
        for (int j = i; j <= 10; j++) {
          assertEquals(i, Objects.checkFromToIndex(i, j, 10));
        }
      }
      assertEquals(0, Objects.checkFromToIndex(0, 0, 0));

      try {
        throw new AssertionError(Objects.checkFromToIndex(4, 2, 10));
      } catch (IndexOutOfBoundsException expected) {
      }
      try {
        throw new AssertionError(Objects.checkFromToIndex(-1, 5, 10));
      } catch (IndexOutOfBoundsException expected) {
      }
      try {
        throw new AssertionError(Objects.checkFromToIndex(0, -1, 10));
      } catch (IndexOutOfBoundsException expected) {
      }
      try {
        throw new AssertionError(Objects.checkFromToIndex(11, 11, 10));
      } catch (IndexOutOfBoundsException expected) {
      }
      try {
        throw new AssertionError(Objects.checkFromToIndex(0, 1, 0));
      } catch (IndexOutOfBoundsException expected) {
      }
      try {
        throw new AssertionError(Objects.checkFromToIndex(1, 1, 0));
      } catch (IndexOutOfBoundsException expected) {
      }
    }

    private static void testCheckFromIndexSize() {
      for (int i = 0; i <= 10; i++) {
        for (int j = 10 - i; j >= 0; j--) {
          assertEquals(i, Objects.checkFromIndexSize(i, j, 10));
        }
      }
      assertEquals(0, Objects.checkFromIndexSize(0, 0, 0));

      try {
        throw new AssertionError(Objects.checkFromIndexSize(8, 4, 10));
      } catch (IndexOutOfBoundsException expected) {
      }
      try {
        throw new AssertionError(Objects.checkFromIndexSize(-1, 5, 10));
      } catch (IndexOutOfBoundsException expected) {
      }
      try {
        throw new AssertionError(Objects.checkFromIndexSize(11, 0, 10));
      } catch (IndexOutOfBoundsException expected) {
      }
      try {
        throw new AssertionError(Objects.checkFromIndexSize(0, 1, 0));
      } catch (IndexOutOfBoundsException expected) {
      }
      try {
        throw new AssertionError(Objects.checkFromIndexSize(1, 1, 0));
      } catch (IndexOutOfBoundsException expected) {
      }

      // Check for cases where overflow might occur producing incorrect results.
      try {
        throw new AssertionError(
            Objects.checkFromIndexSize(Integer.MAX_VALUE, 1, Integer.MAX_VALUE));
      } catch (IndexOutOfBoundsException expected) {
      }
      try {
        throw new AssertionError(Objects.checkFromIndexSize(0, 1, Integer.MIN_VALUE));
      } catch (IndexOutOfBoundsException expected) {
      }
    }

    private static void assertEquals(int expected, int actual) {
      if (expected != actual) {
        throw new AssertionError("Expected <" + expected + "> but was <" + actual + '>');
      }
    }

    private static void assertSame(Object expected, Object actual) {
      if (expected != actual) {
        throw new AssertionError(
            "Expected <" + expected + "> to be same instance as <" + actual + '>');
      }
    }
  }
}