/*
 * Copyright 2019 The Error Prone Authors.
 *
 * 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.errorprone.bugpatterns;

import com.google.common.collect.ImmutableList;
import com.google.errorprone.BugCheckerRefactoringTestHelper;
import com.google.errorprone.CompilationTestHelper;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

/** Unit tests for {@link SameNameButDifferent}. */
@RunWith(JUnit4.class)
public final class SameNameButDifferentTest {

  private final CompilationTestHelper helper =
      CompilationTestHelper.newInstance(SameNameButDifferent.class, getClass());

  private final BugCheckerRefactoringTestHelper refactoring =
      BugCheckerRefactoringTestHelper.newInstance(SameNameButDifferent.class, getClass());

  @Test
  public void simpleNameClash() {
    helper
        .addSourceLines(
            "A.java",
            """
            class A {
              class Supplier {}
            }
            """)
        .addSourceLines(
            "B.java",
            """
            import java.util.function.Supplier;

            class B {
              // BUG: Diagnostic contains:
              Supplier<Integer> supplier = () -> 1;

              class C extends A {
                // BUG: Diagnostic contains:
                Supplier supplier2 = new Supplier();
              }
            }
            """)
        .doTest();
  }

  @Test
  public void simpleNameRefactoring() {
    refactoring
        .addInputLines(
            "A.java",
            """
            package foo;

            class A {
              class Supplier {}
            }
            """)
        .expectUnchanged()
        .addInputLines(
            "B.java",
            """
            package foo;

            import java.util.function.Supplier;

            class B {
              Supplier<Integer> supplier = () -> 1;

              class C extends A {
                Supplier supplier2 = new Supplier();
                Class<Supplier> clazz = Supplier.class;
              }
            }
            """)
        .addOutputLines(
            "B.java",
            """
            package foo;

            import java.util.function.Supplier;

            class B {
              Supplier<Integer> supplier = () -> 1;

              class C extends A {
                A.Supplier supplier2 = new A.Supplier();
                Class<A.Supplier> clazz = A.Supplier.class;
              }
            }
            """)
        .doTest();
  }

  @Test
  public void nestedClassNameClash() {
    refactoring
        .addInputLines(
            "A.java",
            """
            package foo;

            class A {
              static class B {
                static class C {}
              }
            }
            """)
        .expectUnchanged()
        .addInputLines(
            "D.java",
            """
            package foo;

            class D {
              static class B {
                static class C {}
              }
            }
            """)
        .expectUnchanged()
        .addInputLines(
            "E.java",
            """
            package foo;

            import foo.A.B;

            class E {
              B.C foo = new B.C();

              class C extends D {
                B.C bar = new B.C();
              }
            }
            """)
        .addOutputLines(
            "E.java",
            """
            package foo;

            import foo.A.B;

            class E {
              A.B.C foo = new A.B.C();

              class C extends D {
                D.B.C bar = new D.B.C();
              }
            }
            """)
        .doTest();
  }

  @Test
  public void negativeAlreadyQualified() {
    helper
        .addSourceLines(
            "A.java",
            """
            class A {
              class Supplier {}
            }
            """)
        .addSourceLines(
            "B.java",
            """
            import java.util.function.Supplier;

            class B {
              Supplier<Integer> supplier = () -> 1;

              class C extends A {
                A.Supplier supplier2 = new A.Supplier();
              }
            }
            """)
        .doTest();
  }

  @Test
  public void neverShadowing() {
    helper
        .addSourceLines(
            "A.java",
            """
            class A {
              public void foo() {
                class B {}
                B b = new B();
              }

              public void bar() {
                class B {}
                B b = new B();
              }
            }
            """)
        .doTest();
  }

  @Test
  public void doesNotThrowConcurrentModification_whenFilteringNonShadowingTypeNames() {
    helper
        .addSourceLines(
            "A.java",
            """
            class A {
              public void foo() {
                class B {}
                B b = new B();
              }

              public void bar() {
                class B {}
                class C {}
                C c = new C();
                B b = new B();
              }
            }
            """)
        .doTest();
  }

  @Test
  public void referencesSelf() {
    helper
        .addSourceLines(
            "B.java",
            """
            import java.util.function.Supplier;

            class B {
              Supplier<Integer> supplier = () -> 1;

              class C {
                class Supplier {
                  Supplier s = new Supplier();
                }
              }
            }
            """)
        .doTest();
  }

  @Test
  public void ungroupedOverloadsPositiveCasesCoveringOnlyFirstOverload() {
    helper
        .addSourceLines(
            "Test.java",
            """
            import java.util.function.Supplier;

            class Test {
              class One {
                class Clash {}

                // BUG: Diagnostic contains:
                Clash a;
                Clash b;
              }

              class Two {
                class Clash {}

                Clash a;
                Clash b;
              }
            }
            """)
        .setArgs(ImmutableList.of("-XepOpt:SameNameButDifferent:BatchFindings"))
        .doTest();
  }
}
