/*
 * Copyright 2009 Google Inc.
 * 
 * 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.gwt.dev.javac;

import com.google.gwt.dev.javac.impl.JavaResourceBase;
import com.google.gwt.dev.javac.impl.MockJavaResource;
import com.google.gwt.dev.resource.Resource;

import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

/**
 * Test if all fileReferences in a compilationUnit are recorded correctly.
 */
public class CompilationUnitFileReferenceTest extends CompilationStateTestBase {

  public static final MockJavaResource MEMBER_INNER_SUBCLASS = new MockJavaResource(
      "test.OuterSubclass") {
    @Override
    protected CharSequence getContent() {
      StringBuffer code = new StringBuffer();
      code.append("package test;\n");
      code.append("public class OuterSubclass extends Outer {\n");
      code.append("  public String value() { return \"OuterSubclass\"; }\n");
      code.append("  public class MemberInnerSubclass extends MemberInner {\n");
      code.append("    public String value() { return \"MemberInnerSubclass\"; }\n");
      code.append("  }\n");
      code.append("}\n");
      return code;
    }
  };

  public static final MockJavaResource NOPACKAGE = new MockJavaResource(
      "NoPackage") {
    @Override
    protected CharSequence getContent() {
      StringBuffer code = new StringBuffer();
      code.append("public class NoPackage extends test.Top {\n");
      code.append("  public String value() { return \"NoPackage\"; }\n");
      code.append("}\n");
      return code;
    }
  };

  public static final MockJavaResource NOPACKAGE2 = new MockJavaResource(
      "NoPackage2") {
    @Override
    protected CharSequence getContent() {
      StringBuffer code = new StringBuffer();
      code.append("public class NoPackage2 extends NoPackage {\n");
      code.append("  public String value() { return \"NoPackage2\"; }\n");
      code.append("}\n");
      return code;
    }
  };

  public static final MockJavaResource OUTER = new MockJavaResource(
      "test.Outer") {
    @Override
    protected CharSequence getContent() {
      StringBuffer code = new StringBuffer();
      code.append("package test;\n");
      code.append("public class Outer {\n");
      code.append("  public String value() { return \"Outer\"; }\n");
      code.append("  public static class StaticInner {\n");
      code.append("    public String value() { return \"StaticInner\"; }\n");
      code.append("  }\n");
      code.append("  public class MemberInner {\n");
      code.append("    public String value() { return \"MemberInner\"; }\n");
      code.append("  }\n");
      code.append("}\n");
      return code;
    }
  };

  public static final MockJavaResource STATIC_INNER_SUBCLASS = new MockJavaResource(
      "test.StaticInnerSubclass") {
    @Override
    protected CharSequence getContent() {
      StringBuffer code = new StringBuffer();
      code.append("package test;\n");
      code.append("public class StaticInnerSubclass extends Outer.StaticInner {\n");
      code.append("  public String value() { return \"StaticInnerSubclass\"; }\n");
      code.append("}\n");
      return code;
    }
  };

  public static final MockJavaResource TOP = new MockJavaResource("test.Top") {
    @Override
    protected CharSequence getContent() {
      StringBuffer code = new StringBuffer();
      code.append("package test;\n");
      code.append("public class Top {\n");
      code.append("  public String value() { return \"Top\"; }\n");
      code.append("}\n");
      code.append("class Top2 extends Top {\n");
      code.append("  public String value() { return \"Top2\"; }\n");
      code.append("}\n");
      return code;
    }
  };

  public static final MockJavaResource TOP3 = new MockJavaResource("test.Top3") {
    @Override
    protected CharSequence getContent() {
      StringBuffer code = new StringBuffer();
      code.append("package test;\n");
      code.append("public class Top3 extends Top2 {\n");
      code.append("  public String value() { return \"Top3\"; }\n");
      code.append("}\n");
      return code;
    }
  };

  /**
   * This map contains the hand-computed set of references we expect each of the
   * test compilation units to have. The actual set of references computed by
   * {@link CompilationState} will be checked against this set.
   */
  private static final Map<String, Set<String>> EXPECTED_DEPENDENCIES = new HashMap<String, Set<String>>();

  static {
    // Setup EXPECTED_DEPENDENCIES with hand-computed data.
    initializeExpectedDependency(JavaResourceBase.FOO, JavaResourceBase.STRING);
    initializeExpectedDependency(JavaResourceBase.BAR, JavaResourceBase.STRING,
        JavaResourceBase.FOO);

    initializeExpectedDependency(NOPACKAGE, JavaResourceBase.STRING, TOP);
    initializeExpectedDependency(NOPACKAGE2, NOPACKAGE,
        JavaResourceBase.STRING, TOP);

    initializeExpectedDependency(TOP, JavaResourceBase.STRING);
    initializeExpectedDependency(TOP3, JavaResourceBase.STRING, TOP);

    initializeExpectedDependency(OUTER, JavaResourceBase.STRING);
    initializeExpectedDependency(MEMBER_INNER_SUBCLASS,
        JavaResourceBase.STRING, OUTER);

    initializeExpectedDependency(OUTER, JavaResourceBase.STRING);
    initializeExpectedDependency(STATIC_INNER_SUBCLASS,
        JavaResourceBase.STRING, OUTER);
  }

  private static void initializeExpectedDependency(MockJavaResource source,
      MockJavaResource... targets) {
    Set<String> targetSet = new HashSet<String>();
    for (MockJavaResource target : targets) {
      targetSet.add(target.getTypeName());
    }
    EXPECTED_DEPENDENCIES.put(source.getTypeName(), targetSet);
  }

  public void testBinaryBindingsWithMemberInnerClass() {
    testBinaryBindings(OUTER, MEMBER_INNER_SUBCLASS);
  }

  public void testBinaryBindingsWithMultipleTopLevelClasses() {
    testBinaryBindings(TOP, TOP3);
  }

  public void testBinaryBindingsWithSimpleUnits() {
    testBinaryBindings(JavaResourceBase.FOO, JavaResourceBase.BAR);
  }

  public void testBinaryBindingsWithStaticInnerClass() {
    testBinaryBindings(OUTER, STATIC_INNER_SUBCLASS);
  }

  public void testBinaryNoPackage() {
    testBinaryBindings(TOP, NOPACKAGE, NOPACKAGE2);
  }

  public void testSourceBindingsWithMemberInnerClass() {
    testSourceBindings(OUTER, MEMBER_INNER_SUBCLASS);
  }

  public void testSourceBindingsWithMultipleTopLevelClasses() {
    testSourceBindings(TOP, TOP3);
  }

  public void testSourceBindingsWithSimpleUnits() {
    testSourceBindings(JavaResourceBase.FOO, JavaResourceBase.BAR);
  }

  public void testSourceBindingsWithStaticInnerClass() {
    testSourceBindings(OUTER, STATIC_INNER_SUBCLASS);
  }

  public void testSourceNoPackage() {
    testSourceBindings(TOP, NOPACKAGE, NOPACKAGE2);
  }

  public void testWithGeneratedUnits() {
    addGeneratedUnits(JavaResourceBase.FOO, JavaResourceBase.BAR);
    assertRefsMatchExpectedRefs(JavaResourceBase.FOO, JavaResourceBase.BAR);
  }

  public void testWithMixedUnits() {
    oracle.add(JavaResourceBase.FOO);
    rebuildCompilationState();
    addGeneratedUnits(JavaResourceBase.BAR);
    assertRefsMatchExpectedRefs(JavaResourceBase.FOO, JavaResourceBase.BAR);
  }

  private void assertRefsMatchExpectedRefs(MockJavaResource... files) {
    Map<String, CompilationUnit> unitMap = state.getCompilationUnitMap();
    for (MockJavaResource file : files) {
      String typeName = file.getTypeName();
      Dependencies dependencies = unitMap.get(typeName).getDependencies();
      Set<CompiledClass> classDeps = new HashSet<CompiledClass>();
      classDeps.addAll(dependencies.qualified.values());
      classDeps.addAll(dependencies.simple.values());
      classDeps.remove(null);
      Set<String> actualTypeNames = new HashSet<String>();
      for (CompiledClass cc : classDeps) {
        actualTypeNames.add(cc.getUnit().getTypeName());
      }
      // Not tracking deps on Object.
      actualTypeNames.remove("java.lang.Object");
      // Don't care about self dep.
      actualTypeNames.remove(typeName);
      Set<String> expectedTypeNames = EXPECTED_DEPENDENCIES.get(typeName);
      assertEquals(expectedTypeNames, actualTypeNames);
    }
  }

  /**
   * Independently compiles each file in order to force each subsequent unit to
   * have only binary references to the previous unit(s). This tests the binary
   * reference matching in {@link CompilationState}.
   */
  private void testBinaryBindings(MockJavaResource... files) {
    for (Resource sourceFile : files) {
      oracle.add(sourceFile);
      rebuildCompilationState();
    }
    assertRefsMatchExpectedRefs(files);
  }

  /**
   * Compiles all files together so that all units will have source references
   * to each other. This tests the source reference matching in
   * {@link CompilationState}.
   */
  private void testSourceBindings(MockJavaResource... files) {
    for (Resource sourceFile : files) {
      oracle.add(sourceFile);
    }
    rebuildCompilationState();
    assertRefsMatchExpectedRefs(files);
  }
}