// Copyright 2017 The Bazel 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 com.google.devtools.build.lib.rules.platform;

import static com.google.common.truth.Truth.assertThat;

import com.google.common.collect.ImmutableMap;
import com.google.devtools.build.lib.analysis.ConfiguredTarget;
import com.google.devtools.build.lib.analysis.platform.ConstraintSettingInfo;
import com.google.devtools.build.lib.analysis.platform.ConstraintValueInfo;
import com.google.devtools.build.lib.analysis.platform.PlatformProviderUtils;
import com.google.devtools.build.lib.analysis.util.BuildViewTestCase;
import com.google.devtools.build.lib.cmdline.Label;
import com.google.devtools.build.lib.packages.StarlarkProvider;
import com.google.devtools.build.lib.packages.StructImpl;
import com.google.devtools.build.lib.syntax.Starlark;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

/** Tests of {@link ConstraintSetting} and {@link ConstraintValue}. */
@RunWith(JUnit4.class)
public class ConstraintTest extends BuildViewTestCase {

  @Before
  public void createConstraints() throws Exception {
    scratch.file(
        "constraint/BUILD",
        "constraint_setting(name = 'basic')",
        "constraint_value(name = 'foo',",
        "    constraint_setting = ':basic',",
        "    )",
        "constraint_value(name = 'bar',",
        "    constraint_setting = ':basic',",
        "    )");
  }

  @Test
  public void testConstraint() throws Exception {
    ConfiguredTarget setting = getConfiguredTarget("//constraint:basic");
    assertThat(setting).isNotNull();

    ConstraintSettingInfo constraintSettingInfo = PlatformProviderUtils.constraintSetting(setting);
    assertThat(constraintSettingInfo).isNotNull();
    assertThat(constraintSettingInfo).isNotNull();
    assertThat(constraintSettingInfo.label())
        .isEqualTo(Label.parseAbsolute("//constraint:basic", ImmutableMap.of()));
    assertThat(constraintSettingInfo.hasDefaultConstraintValue()).isFalse();
    assertThat(constraintSettingInfo.defaultConstraintValue()).isNull();

    ConfiguredTarget fooValue = getConfiguredTarget("//constraint:foo");
    assertThat(fooValue).isNotNull();

    ConstraintValueInfo fooConstraintValueInfo = PlatformProviderUtils.constraintValue(fooValue);
    assertThat(fooConstraintValueInfo).isNotNull();
    assertThat(fooConstraintValueInfo.constraint().label())
        .isEqualTo(Label.parseAbsolute("//constraint:basic", ImmutableMap.of()));
    assertThat(fooConstraintValueInfo.label())
        .isEqualTo(Label.parseAbsolute("//constraint:foo", ImmutableMap.of()));

    ConfiguredTarget barValue = getConfiguredTarget("//constraint:bar");
    assertThat(barValue).isNotNull();

    ConstraintValueInfo barConstraintValueInfo = PlatformProviderUtils.constraintValue(barValue);
    assertThat(barConstraintValueInfo.constraint().label())
        .isEqualTo(Label.parseAbsolute("//constraint:basic", ImmutableMap.of()));
    assertThat(barConstraintValueInfo.label())
        .isEqualTo(Label.parseAbsolute("//constraint:bar", ImmutableMap.of()));
  }

  @Test
  public void testConstraint_defaultValue() throws Exception {
    scratch.file(
        "constraint_default/BUILD",
        "constraint_setting(name = 'basic',",
        "    default_constraint_value = ':foo',",
        ")",
        "constraint_value(name = 'foo',",
        "    constraint_setting = ':basic',",
        ")",
        "constraint_value(name = 'bar',",
        "    constraint_setting = ':basic',",
        ")");

    ConfiguredTarget setting = getConfiguredTarget("//constraint_default:basic");
    assertThat(setting).isNotNull();
    ConstraintSettingInfo constraintSettingInfo = PlatformProviderUtils.constraintSetting(setting);
    assertThat(constraintSettingInfo).isNotNull();
    assertThat(constraintSettingInfo.hasDefaultConstraintValue()).isTrue();

    ConfiguredTarget fooValue = getConfiguredTarget("//constraint_default:foo");
    assertThat(fooValue).isNotNull();
    ConstraintValueInfo fooConstraintValueInfo = PlatformProviderUtils.constraintValue(fooValue);
    assertThat(fooConstraintValueInfo).isNotNull();

    assertThat(constraintSettingInfo.defaultConstraintValue()).isEqualTo(fooConstraintValueInfo);
  }

  @Test
  public void testConstraint_defaultValue_differentPackageFails() throws Exception {
    scratch.file(
        "other/BUILD",
        "constraint_value(name = 'other',",
        "    constraint_setting = '//constraint_default:basic',",
        ")");
    checkError(
        "constraint_default",
        "basic",
        "same package",
        "constraint_setting(name = 'basic',",
        "    default_constraint_value = '//other:other',",
        ")");
  }

  @Test
  public void testConstraint_defaultValue_nonExistentTargetFails() throws Exception {
    checkError(
        "constraint_default",
        "basic",
        "default constraint value '//constraint_default:food' does not exist",
        "constraint_setting(name = 'basic',",
        "    default_constraint_value = ':food',",
        "    )",
        "constraint_value(name = 'foo',",
        "    constraint_setting = ':basic',",
        ")");
  }

  @Test
  public void testConstraint_defaultValue_starlark() throws Exception {
    setStarlarkSemanticsOptions("--experimental_platforms_api=true");
    scratch.file(
        "constraint_default/BUILD",
        "constraint_setting(name = 'basic',",
        "    default_constraint_value = ':foo',",
        ")",
        "constraint_value(name = 'foo',",
        "    constraint_setting = ':basic',",
        ")");

    scratch.file(
        "verify/verify.bzl",
        "result = provider()",
        "def _impl(ctx):",
        "  constraint_setting = ctx.attr.constraint_setting[platform_common.ConstraintSettingInfo]",
        "  default_value = constraint_setting.default_constraint_value",
        "  has_default_value = constraint_setting.has_default_constraint_value",
        "  return [result(",
        "    default_value = default_value,",
        "    has_default_value = has_default_value,",
        "  )]",
        "verify = rule(",
        "  implementation = _impl,",
        "  attrs = {",
        "    'constraint_setting': attr.label(",
        "        providers = [platform_common.ConstraintSettingInfo]),",
        "  },",
        ")");
    scratch.file(
        "verify/BUILD",
        "load(':verify.bzl', 'verify')",
        "verify(name = 'verify',",
        "  constraint_setting = '//constraint_default:basic',",
        ")");

    ConfiguredTarget myRuleTarget = getConfiguredTarget("//verify:verify");
    StructImpl info =
        (StructImpl)
            myRuleTarget.get(
                new StarlarkProvider.Key(
                    Label.parseAbsolute("//verify:verify.bzl", ImmutableMap.of()), "result"));

    @SuppressWarnings("unchecked")
    ConstraintValueInfo defaultConstraintValue =
        (ConstraintValueInfo) info.getValue("default_value");
    assertThat(defaultConstraintValue).isNotNull();
    assertThat(defaultConstraintValue.label())
        .isEqualTo(Label.parseAbsoluteUnchecked("//constraint_default:foo"));
    assertThat(defaultConstraintValue.constraint().label())
        .isEqualTo(Label.parseAbsoluteUnchecked("//constraint_default:basic"));

    boolean hasConstraintValue = (boolean) info.getValue("has_default_value");
    assertThat(hasConstraintValue).isTrue();
  }

  @Test
  public void testConstraint_defaultValue_notSet_starlark() throws Exception {
    setStarlarkSemanticsOptions("--experimental_platforms_api=true");
    scratch.file("constraint_default/BUILD", "constraint_setting(name = 'basic')");

    scratch.file(
        "verify/verify.bzl",
        "result = provider()",
        "def _impl(ctx):",
        "  constraint_setting = ctx.attr.constraint_setting[platform_common.ConstraintSettingInfo]",
        "  default_value = constraint_setting.default_constraint_value",
        "  has_default_value = constraint_setting.has_default_constraint_value",
        "  return [result(",
        "    default_value = default_value,",
        "    has_default_value = has_default_value,",
        "  )]",
        "verify = rule(",
        "  implementation = _impl,",
        "  attrs = {",
        "    'constraint_setting': attr.label(",
        "        providers = [platform_common.ConstraintSettingInfo]),",
        "  },",
        ")");
    scratch.file(
        "verify/BUILD",
        "load(':verify.bzl', 'verify')",
        "verify(name = 'verify',",
        "  constraint_setting = '//constraint_default:basic',",
        ")");

    ConfiguredTarget myRuleTarget = getConfiguredTarget("//verify:verify");
    StructImpl info =
        (StructImpl)
            myRuleTarget.get(
                new StarlarkProvider.Key(
                    Label.parseAbsolute("//verify:verify.bzl", ImmutableMap.of()), "result"));

    assertThat(info.getValue("default_value")).isEqualTo(Starlark.NONE);

    boolean hasConstraintValue = (boolean) info.getValue("has_default_value");
    assertThat(hasConstraintValue).isFalse();
  }
}