// Copyright 2015 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.docgen;

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

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Sets;
import com.google.devtools.build.docgen.StarlarkDocumentationProcessor.Category;
import com.google.devtools.build.docgen.annot.DocCategory;
import com.google.devtools.build.docgen.annot.GlobalMethods;
import com.google.devtools.build.docgen.annot.GlobalMethods.Environment;
import com.google.devtools.build.docgen.annot.StarlarkConstructor;
import com.google.devtools.build.docgen.starlark.StarlarkConstructorMethodDoc;
import com.google.devtools.build.docgen.starlark.StarlarkDoc;
import com.google.devtools.build.docgen.starlark.StarlarkDocExpander;
import com.google.devtools.build.docgen.starlark.StarlarkDocPage;
import com.google.devtools.build.docgen.starlark.StarlarkMethodDoc;
import com.google.devtools.build.lib.analysis.starlark.StarlarkGlobalsImpl;
import com.google.devtools.build.lib.analysis.starlark.StarlarkRuleContext;
import com.google.devtools.build.lib.collect.nestedset.Depset;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;
import java.util.stream.Stream;
import net.starlark.java.annot.Param;
import net.starlark.java.annot.StarlarkBuiltin;
import net.starlark.java.annot.StarlarkMethod;
import net.starlark.java.eval.Dict;
import net.starlark.java.eval.Sequence;
import net.starlark.java.eval.StarlarkList;
import net.starlark.java.eval.StarlarkValue;
import net.starlark.java.eval.Tuple;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

/** Tests for Starlark documentation. */
@RunWith(JUnit4.class)
public class StarlarkDocumentationTest {

  private static final ImmutableList<String> DEPRECATED_UNDOCUMENTED_TOP_LEVEL_SYMBOLS =
      ImmutableList.of("Actions");

  private static final StarlarkDocExpander expander =
      new StarlarkDocExpander(null) {

        @Override
        public String expand(String docString) {
          return docString;
        }
      };

  @Test
  public void testStarlarkRuleClassBuiltInItemsAreDocumented() throws Exception {
    checkStarlarkTopLevelEnvItemsAreDocumented(StarlarkGlobalsImpl.INSTANCE.getFixedBzlToplevels());
  }

  private void checkStarlarkTopLevelEnvItemsAreDocumented(Map<String, Object> globals)
      throws Exception {
    ImmutableMap<Category, ImmutableList<StarlarkDocPage>> allPages =
        StarlarkDocumentationCollector.getAllDocPages(expander);
    ImmutableSet<String> documentedItems =
        Stream.concat(
                allPages.get(Category.GLOBAL_FUNCTION).stream()
                    .flatMap(p -> p.getMethods().stream()),
                allPages.entrySet().stream()
                    .filter(e -> !e.getKey().equals(Category.GLOBAL_FUNCTION))
                    .flatMap(e -> e.getValue().stream()))
            .filter(m -> !m.getDocumentation().isEmpty())
            .map(StarlarkDoc::getName)
            .collect(ImmutableSet.toImmutableSet());

    assertThat(
            Sets.difference(
                Sets.difference(globals.keySet(), documentedItems),
                // These constants are currently undocumented.
                // If they need documentation, the easiest approach would be
                // to hard-code it in StarlarkDocumentationCollector.
                ImmutableSet.of("True", "False", "None")))
        .containsExactlyElementsIn(DEPRECATED_UNDOCUMENTED_TOP_LEVEL_SYMBOLS);
  }

  // TODO(bazel-team): come up with better Starlark specific tests.
  @Test
  public void testDirectJavaMethodsAreGenerated() throws Exception {
    assertThat(collect(StarlarkRuleContext.class)).isNotEmpty();
  }

  /** MockClassA */
  @StarlarkBuiltin(name = "MockClassA", category = DocCategory.BUILTIN, doc = "MockClassA")
  private static class MockClassA implements StarlarkValue {
    @StarlarkMethod(name = "get", doc = "MockClassA#get")
    public Integer get() {
      return 0;
    }
  }

  /** MockClassD */
  @StarlarkBuiltin(name = "MockClassD", category = DocCategory.BUILTIN, doc = "MockClassD")
  private static class MockClassD implements StarlarkValue {
    @StarlarkMethod(
        name = "test",
        doc = "MockClassD#test",
        parameters = {
          @Param(name = "a"),
          @Param(name = "b"),
          @Param(name = "c", named = true, positional = false),
          @Param(name = "d", named = true, positional = false, defaultValue = "1"),
        })
    public Integer test(int a, int b, int c, int d) {
      return 0;
    }
  }

  /** MockClassE */
  @StarlarkBuiltin(name = "MockClassE", category = DocCategory.BUILTIN, doc = "MockClassE")
  private static class MockClassE extends MockClassA {
    @Override
    public Integer get() {
      return 1;
    }
  }

  /** MockClassF */
  @StarlarkBuiltin(name = "MockClassF", category = DocCategory.BUILTIN, doc = "MockClassF")
  private static class MockClassF implements StarlarkValue {
    @StarlarkMethod(
        name = "test",
        doc = "MockClassF#test",
        parameters = {
          @Param(name = "a", named = false, positional = true),
          @Param(name = "b", named = true, positional = true),
          @Param(name = "c", named = true, positional = false),
          @Param(name = "d", named = true, positional = false, defaultValue = "1"),
        },
        extraPositionals = @Param(name = "myArgs"))
    public Integer test(int a, int b, int c, int d, Sequence<?> args) {
      return 0;
    }
  }

  /** MockClassG */
  @StarlarkBuiltin(name = "MockClassG", category = DocCategory.BUILTIN, doc = "MockClassG")
  private static class MockClassG implements StarlarkValue {
    @StarlarkMethod(
        name = "test",
        doc = "MockClassG#test",
        parameters = {
          @Param(name = "a", named = false, positional = true),
          @Param(name = "b", named = true, positional = true),
          @Param(name = "c", named = true, positional = false),
          @Param(name = "d", named = true, positional = false, defaultValue = "1"),
        },
        extraKeywords = @Param(name = "myKwargs"))
    public Integer test(int a, int b, int c, int d, Dict<?, ?> kwargs) {
      return 0;
    }
  }

  /** MockClassH */
  @StarlarkBuiltin(name = "MockClassH", category = DocCategory.BUILTIN, doc = "MockClassH")
  private static class MockClassH implements StarlarkValue {
    @StarlarkMethod(
        name = "test",
        doc = "MockClassH#test",
        parameters = {
          @Param(name = "a", named = false, positional = true),
          @Param(name = "b", named = true, positional = true),
          @Param(name = "c", named = true, positional = false),
          @Param(name = "d", named = true, positional = false, defaultValue = "1"),
        },
        extraPositionals = @Param(name = "myArgs"),
        extraKeywords = @Param(name = "myKwargs"))
    public Integer test(int a, int b, int c, int d, Sequence<?> args, Dict<?, ?> kwargs) {
      return 0;
    }
  }

  /** MockClassI */
  @StarlarkBuiltin(name = "MockClassI", category = DocCategory.BUILTIN, doc = "MockClassI")
  private static class MockClassI implements StarlarkValue {
    @StarlarkMethod(
        name = "test",
        doc = "MockClassI#test",
        parameters = {
          @Param(name = "a", named = false, positional = true),
          @Param(name = "b", named = true, positional = true),
          @Param(name = "c", named = true, positional = false),
          @Param(name = "d", named = true, positional = false, defaultValue = "1"),
          @Param(
              name = "e",
              named = true,
              positional = false,
              documented = false,
              defaultValue = "2"),
        },
        extraPositionals = @Param(name = "myArgs"))
    public Integer test(int a, int b, int c, int d, int e, Sequence<?> args) {
      return 0;
    }
  }

  /**
   * MockGlobalLibrary. While nothing directly depends on it, a test method in
   * StarlarkDocumentationTest checks all of the classes under a wide classpath and ensures this one
   * shows up.
   */
  @GlobalMethods(environment = Environment.BZL)
  @SuppressWarnings("unused")
  private static class MockGlobalLibrary {
    @StarlarkMethod(
        name = "MockGlobalCallable",
        doc = "GlobalCallable documentation",
        parameters = {
          @Param(name = "a", named = false, positional = true),
          @Param(name = "b", named = true, positional = true),
          @Param(name = "c", named = true, positional = false),
          @Param(name = "d", named = true, positional = false, defaultValue = "1"),
        },
        extraPositionals = @Param(name = "myArgs"),
        extraKeywords = @Param(name = "myKwargs"))
    public Integer test(int a, int b, int c, int d, Sequence<?> args, Dict<?, ?> kwargs) {
      return 0;
    }
  }

  /** MockClassWithContainerReturnValues */
  @StarlarkBuiltin(
      name = "MockClassWithContainerReturnValues",
      category = DocCategory.BUILTIN,
      doc = "MockClassWithContainerReturnValues")
  private static class MockClassWithContainerReturnValues implements StarlarkValue {

    @StarlarkMethod(name = "depset", doc = "depset")
    public Depset /*<Integer>*/ getNestedSet() {
      return null;
    }

    @StarlarkMethod(name = "tuple", doc = "tuple")
    public Tuple getTuple() {
      return null;
    }

    @StarlarkMethod(name = "immutable", doc = "immutable")
    public ImmutableList<Integer> getImmutableList() {
      return null;
    }

    @StarlarkMethod(name = "mutable", doc = "mutable")
    public StarlarkList<Integer> getMutableList() {
      return null;
    }

    @StarlarkMethod(name = "starlark", doc = "starlark")
    public Sequence<Integer> getStarlarkList() {
      return null;
    }
  }

  /** MockClassCommonNameOne */
  @StarlarkBuiltin(
      name = "MockClassCommonName",
      category = DocCategory.BUILTIN,
      doc = "MockClassCommonName")
  private static class MockClassCommonNameOne implements StarlarkValue {

    @StarlarkMethod(name = "one", doc = "one")
    public Integer one() {
      return 1;
    }
  }

  /** SubclassOfMockClassCommonNameOne */
  @StarlarkBuiltin(
      name = "MockClassCommonName",
      category = DocCategory.BUILTIN,
      doc = "MockClassCommonName")
  private static class SubclassOfMockClassCommonNameOne extends MockClassCommonNameOne {

    @StarlarkMethod(name = "two", doc = "two")
    public Integer two() {
      return 1;
    }
  }

  /** PointsToCommonNameOneWithSubclass */
  @StarlarkBuiltin(
      name = "PointsToCommonNameOneWithSubclass",
      category = DocCategory.BUILTIN,
      doc = "PointsToCommonNameOneWithSubclass")
  private static class PointsToCommonNameOneWithSubclass implements StarlarkValue {
    @StarlarkMethod(name = "one", doc = "one")
    public MockClassCommonNameOne getOne() {
      return null;
    }

    @StarlarkMethod(name = "one_subclass", doc = "one_subclass")
    public SubclassOfMockClassCommonNameOne getOneSubclass() {
      return null;
    }
  }

  /** MockClassCommonNameOneUndocumented */
  @StarlarkBuiltin(name = "MockClassCommonName", documented = false, doc = "")
  private static class MockClassCommonNameUndocumented implements StarlarkValue {

    @StarlarkMethod(name = "two", doc = "two")
    public Integer two() {
      return 1;
    }
  }

  /** PointsToCommonNameAndUndocumentedModule */
  @StarlarkBuiltin(
      name = "PointsToCommonNameAndUndocumentedModule",
      category = DocCategory.BUILTIN,
      doc = "PointsToCommonNameAndUndocumentedModule")
  private static class PointsToCommonNameAndUndocumentedModule implements StarlarkValue {
    @StarlarkMethod(name = "one", doc = "one")
    public MockClassCommonNameOne getOne() {
      return null;
    }

    @StarlarkMethod(name = "undocumented_module", doc = "undocumented_module")
    public MockClassCommonNameUndocumented getUndocumented() {
      return null;
    }
  }

  /** A module which has a selfCall method which constructs copies of MockClassA. */
  @StarlarkBuiltin(
      name = "MockClassWithSelfCallConstructor",
      category = DocCategory.BUILTIN,
      doc = "MockClassWithSelfCallConstructor")
  private static class MockClassWithSelfCallConstructor implements StarlarkValue {
    @StarlarkMethod(name = "one", doc = "one")
    public MockClassCommonNameOne getOne() {
      return null;
    }

    @StarlarkMethod(name = "makeMockClassA", selfCall = true, doc = "makeMockClassA")
    @StarlarkConstructor
    public MockClassA makeMockClassA() {
      return new MockClassA();
    }
  }

  @Test
  public void testStarlarkCallableParameters() throws Exception {
    ImmutableMap<Category, ImmutableList<StarlarkDocPage>> objects = collect(MockClassD.class);
    assertThat(objects.get(Category.BUILTIN)).hasSize(1);
    StarlarkDocPage moduleDoc = objects.get(Category.BUILTIN).get(0);
    assertThat(moduleDoc.getDocumentation()).isEqualTo("MockClassD");
    assertThat(moduleDoc.getMethods()).hasSize(1);
    StarlarkMethodDoc methodDoc = moduleDoc.getMethods().iterator().next();
    assertThat(methodDoc.getDocumentation()).isEqualTo("MockClassD#test");
    assertThat(methodDoc.getSignature())
        .isEqualTo(
            "<a class=\"anchor\" href=\"../core/int.html\">int</a> MockClassD.test(a, b, *, c,"
                + " d=1)");
    assertThat(methodDoc.getParams()).hasSize(4);
  }

  @Test
  public void testStarlarkCallableParametersAndArgs() throws Exception {
    ImmutableMap<Category, ImmutableList<StarlarkDocPage>> objects = collect(MockClassF.class);
    assertThat(objects.get(Category.BUILTIN)).hasSize(1);
    StarlarkDocPage moduleDoc = objects.get(Category.BUILTIN).get(0);
    assertThat(moduleDoc.getDocumentation()).isEqualTo("MockClassF");
    assertThat(moduleDoc.getMethods()).hasSize(1);
    StarlarkMethodDoc methodDoc = moduleDoc.getMethods().iterator().next();
    assertThat(methodDoc.getDocumentation()).isEqualTo("MockClassF#test");
    assertThat(methodDoc.getSignature())
        .isEqualTo(
            "<a class=\"anchor\" href=\"../core/int.html\">int</a> "
                + "MockClassF.test(a, b, *, c, d=1, *myArgs)");
    assertThat(methodDoc.getParams()).hasSize(5);
  }

  @Test
  public void testStarlarkCallableParametersAndKwargs() throws Exception {
    ImmutableMap<Category, ImmutableList<StarlarkDocPage>> objects = collect(MockClassG.class);
    assertThat(objects.get(Category.BUILTIN)).hasSize(1);
    StarlarkDocPage moduleDoc = objects.get(Category.BUILTIN).get(0);
    assertThat(moduleDoc.getDocumentation()).isEqualTo("MockClassG");
    assertThat(moduleDoc.getMethods()).hasSize(1);
    StarlarkMethodDoc methodDoc = moduleDoc.getMethods().iterator().next();
    assertThat(methodDoc.getDocumentation()).isEqualTo("MockClassG#test");
    assertThat(methodDoc.getSignature())
        .isEqualTo(
            "<a class=\"anchor\" href=\"../core/int.html\">int</a> "
                + "MockClassG.test(a, b, *, c, d=1, **myKwargs)");
    assertThat(methodDoc.getParams()).hasSize(5);
  }

  @Test
  public void testStarlarkCallableParametersAndArgsAndKwargs() throws Exception {
    ImmutableMap<Category, ImmutableList<StarlarkDocPage>> objects = collect(MockClassH.class);
    assertThat(objects.get(Category.BUILTIN)).hasSize(1);
    StarlarkDocPage moduleDoc = objects.get(Category.BUILTIN).get(0);
    assertThat(moduleDoc.getDocumentation()).isEqualTo("MockClassH");
    assertThat(moduleDoc.getMethods()).hasSize(1);
    StarlarkMethodDoc methodDoc = moduleDoc.getMethods().iterator().next();
    assertThat(methodDoc.getDocumentation()).isEqualTo("MockClassH#test");
    assertThat(methodDoc.getSignature())
        .isEqualTo(
            "<a class=\"anchor\" href=\"../core/int.html\">int</a> "
                + "MockClassH.test(a, b, *, c, d=1, *myArgs, **myKwargs)");
    assertThat(methodDoc.getParams()).hasSize(6);
  }

  @Test
  public void testStarlarkUndocumentedParameters() throws Exception {
    ImmutableMap<Category, ImmutableList<StarlarkDocPage>> objects = collect(MockClassI.class);
    assertThat(objects.get(Category.BUILTIN)).hasSize(1);
    StarlarkDocPage moduleDoc = objects.get(Category.BUILTIN).get(0);
    assertThat(moduleDoc.getDocumentation()).isEqualTo("MockClassI");
    assertThat(moduleDoc.getMethods()).hasSize(1);
    StarlarkMethodDoc methodDoc = moduleDoc.getMethods().iterator().next();
    assertThat(methodDoc.getDocumentation()).isEqualTo("MockClassI#test");
    assertThat(methodDoc.getSignature())
        .isEqualTo(
            "<a class=\"anchor\" href=\"../core/int.html\">int</a> "
                + "MockClassI.test(a, b, *, c, d=1, *myArgs)");
    assertThat(methodDoc.getParams()).hasSize(5);
  }

  @Test
  public void testStarlarkGlobalLibraryCallable() throws Exception {
    StarlarkDocPage topLevel =
        StarlarkDocumentationCollector.getAllDocPages(expander)
            .get(Category.GLOBAL_FUNCTION)
            .stream()
            .filter(p -> p.getTitle().equals(Environment.BZL.getTitle()))
            .findAny()
            .get();

    boolean foundGlobalLibrary = false;
    for (StarlarkMethodDoc methodDoc : topLevel.getMethods()) {
      if (methodDoc.getName().equals("MockGlobalCallable")) {
        assertThat(methodDoc.getDocumentation()).isEqualTo("GlobalCallable documentation");
        assertThat(methodDoc.getSignature())
            .isEqualTo(
                "<a class=\"anchor\" href=\"../core/int.html\">int</a> "
                    + "MockGlobalCallable(a, b, *, c, d=1, *myArgs, **myKwargs)");
        foundGlobalLibrary = true;
        break;
      }
    }
    assertThat(foundGlobalLibrary).isTrue();
  }

  @Test
  public void testStarlarkCallableOverriding() throws Exception {
    ImmutableMap<Category, ImmutableList<StarlarkDocPage>> objects =
        collect(MockClassA.class, MockClassE.class);
    StarlarkDocPage moduleDoc =
        objects.get(Category.BUILTIN).stream()
            .filter(p -> p.getTitle().equals("MockClassE"))
            .findAny()
            .get();
    assertThat(moduleDoc.getDocumentation()).isEqualTo("MockClassE");
    assertThat(moduleDoc.getMethods()).hasSize(1);
    StarlarkMethodDoc methodDoc = moduleDoc.getMethods().iterator().next();
    assertThat(methodDoc.getDocumentation()).isEqualTo("MockClassA#get");
    assertThat(methodDoc.getSignature())
        .isEqualTo("<a class=\"anchor\" href=\"../core/int.html\">int</a> MockClassE.get()");
  }

  @Test
  public void testStarlarkContainerReturnTypesWithoutAnnotations() throws Exception {
    ImmutableMap<Category, ImmutableList<StarlarkDocPage>> objects =
        collect(MockClassWithContainerReturnValues.class);
    assertThat(objects.get(Category.BUILTIN)).hasSize(1);
    StarlarkDocPage moduleDoc = objects.get(Category.BUILTIN).get(0);
    Collection<? extends StarlarkMethodDoc> methods = moduleDoc.getMethods();

    List<String> signatures =
        methods.stream().map(m -> m.getSignature()).collect(Collectors.toList());
    assertThat(signatures).hasSize(5);
    assertThat(signatures)
        .contains(
            "<a class=\"anchor\" href=\"../builtins/depset.html\">depset</a> "
                + "MockClassWithContainerReturnValues.depset()");
    assertThat(signatures)
        .contains(
            "<a class=\"anchor\" href=\"../core/tuple.html\">tuple</a> "
                + "MockClassWithContainerReturnValues.tuple()");
    assertThat(signatures)
        .contains(
            "<a class=\"anchor\" href=\"../core/list.html\">list</a> "
                + "MockClassWithContainerReturnValues.immutable()");
    assertThat(signatures)
        .contains(
            "<a class=\"anchor\" href=\"../core/list.html\">list</a> "
                + "MockClassWithContainerReturnValues.mutable()");
    assertThat(signatures)
        .contains(
            "<a class=\"anchor\" href=\"../core/list.html\">sequence</a> "
                + "MockClassWithContainerReturnValues.starlark()");
  }

  @Test
  public void testDocumentedModuleTakesPrecedence() throws Exception {
    ImmutableMap<Category, ImmutableList<StarlarkDocPage>> objects =
        collect(
            PointsToCommonNameAndUndocumentedModule.class,
            MockClassCommonNameOne.class,
            MockClassCommonNameUndocumented.class);
    Collection<? extends StarlarkMethodDoc> methods =
        objects.get(Category.BUILTIN).stream()
            .filter(p -> p.getTitle().equals("MockClassCommonName"))
            .findAny()
            .get()
            .getMethods();
    List<String> methodNames = methods.stream().map(m -> m.getName()).collect(Collectors.toList());
    assertThat(methodNames).containsExactly("one");
  }

  @Test
  public void testDocumentModuleSubclass() {
    ImmutableMap<Category, ImmutableList<StarlarkDocPage>> objects =
        collect(
            PointsToCommonNameOneWithSubclass.class,
            MockClassCommonNameOne.class,
            SubclassOfMockClassCommonNameOne.class);
    Collection<? extends StarlarkMethodDoc> methods =
        objects.get(Category.BUILTIN).stream()
            .filter(p -> p.getTitle().equals("MockClassCommonName"))
            .findAny()
            .get()
            .getMethods();
    List<String> methodNames = methods.stream().map(m -> m.getName()).collect(Collectors.toList());
    assertThat(methodNames).containsExactly("one", "two");
  }

  @Test
  public void testDocumentSelfcallConstructor() {
    ImmutableMap<Category, ImmutableList<StarlarkDocPage>> objects =
        collect(MockClassA.class, MockClassWithSelfCallConstructor.class);
    Collection<? extends StarlarkMethodDoc> methods =
        objects.get(Category.BUILTIN).stream()
            .filter(p -> p.getTitle().equals("MockClassA"))
            .findAny()
            .get()
            .getMethods();
    StarlarkMethodDoc firstMethod = methods.iterator().next();
    assertThat(firstMethod).isInstanceOf(StarlarkConstructorMethodDoc.class);

    List<String> methodNames = methods.stream().map(m -> m.getName()).collect(Collectors.toList());
    assertThat(methodNames).containsExactly("MockClassA", "get");
  }

  private ImmutableMap<Category, ImmutableList<StarlarkDocPage>> collect(Class<?>... classObjects) {
    return StarlarkDocumentationCollector.collectDocPages(
        ImmutableList.copyOf(classObjects), expander);
  }
}