java/java-impl/src/com/intellij/codeInsight/ExpectedTypeInfoImpl.java

/*
 * Copyright 2000-2013 JetBrains s.r.o.
 *
 * 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.intellij.codeInsight;

import com.intellij.openapi.util.NullableComputable;
import com.intellij.openapi.util.NullableLazyValue;
import com.intellij.openapi.util.VolatileNullableLazyValue;
import com.intellij.psi.PsiMethod;
import com.intellij.psi.PsiType;
import com.intellij.psi.util.PsiUtil;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

public class ExpectedTypeInfoImpl implements ExpectedTypeInfo {
  public static final NullableComputable<String> NULL = new NullableComputable<String>() {
    @Override
    public String compute() {
      return null;
    }
  };
  @NotNull
  private final PsiType type;
  @NotNull
  private final PsiType defaultType;
  private final int kind;
  @NotNull
  private final TailType myTailType;
  private final PsiMethod myCalledMethod;
  @NotNull private final NullableComputable<String> expectedNameComputable;
  @NotNull private final NullableLazyValue<String> expectedNameLazyValue;

  @Override
  public int getKind() {
    return kind;
  }

  @NotNull
  @Override
  public TailType getTailType() {
    return myTailType;
  }

  public ExpectedTypeInfoImpl(@NotNull PsiType type,
                              @Type int kind,
                              @NotNull PsiType defaultType,
                              @NotNull TailType myTailType,
                              PsiMethod calledMethod,
                              @NotNull NullableComputable<String> expectedName) {
    this.type = type;
    this.kind = kind;

    this.myTailType = myTailType;
    this.defaultType = defaultType;
    myCalledMethod = calledMethod;
    this.expectedNameComputable = expectedName;
    expectedNameLazyValue = new VolatileNullableLazyValue<String>() {
      @Nullable
      @Override
      protected String compute() {
        return expectedNameComputable.compute();
      }
    };

    PsiUtil.ensureValidType(type);
    PsiUtil.ensureValidType(defaultType);
  }

  @Nullable
  public String getExpectedName() {
    return expectedNameLazyValue.getValue();
  }

  @Override
  public PsiMethod getCalledMethod() {
    return myCalledMethod;
  }

  @Override
  @NotNull
  public PsiType getType () {
    return type;
  }

  @Override
  @NotNull
  public PsiType getDefaultType () {
    return defaultType;
  }

  public boolean equals(final Object o) {
    if (this == o) return true;
    if (!(o instanceof ExpectedTypeInfoImpl)) return false;

    final ExpectedTypeInfoImpl that = (ExpectedTypeInfoImpl)o;

    if (kind != that.kind) return false;
    if (!defaultType.equals(that.defaultType)) return false;
    if (!myTailType.equals(that.myTailType)) return false;
    if (!type.equals(that.type)) return false;

    return true;
  }

  public int hashCode() {
    int result = type.hashCode();
    result = 31 * result + defaultType.hashCode();
    result = 31 * result + kind;
    result = 31 * result + myTailType.hashCode();
    return result;
  }

  @Override
  public boolean equals(ExpectedTypeInfo obj) {
    return equals((Object)obj);
  }

  @SuppressWarnings({"HardCodedStringLiteral"})
  public String toString() {
    return "ExpectedTypeInfo[type='" + type + "' kind='" + kind + "']";
  }

  @NotNull
  @Override
  public ExpectedTypeInfo[] intersect(@NotNull ExpectedTypeInfo info) {
    ExpectedTypeInfoImpl info1 = (ExpectedTypeInfoImpl)info;

    if (kind == TYPE_STRICTLY) {
      if (info1.kind == TYPE_STRICTLY) {
        if (info1.type.equals(type)) return new ExpectedTypeInfoImpl[] {this};
      }
      else {
        return info1.intersect(this);
      }
    }
    else if (kind == TYPE_OR_SUBTYPE) {
      if (info1.kind == TYPE_STRICTLY) {
        if (type.isAssignableFrom(info1.type)) return new ExpectedTypeInfoImpl[] {info1};
      }
      else if (info1.kind == TYPE_OR_SUBTYPE) {
        PsiType otherType = info1.type;
        if (type.isAssignableFrom(otherType)) return new ExpectedTypeInfoImpl[] {info1};
        else if (otherType.isAssignableFrom(type)) return new ExpectedTypeInfoImpl[] {this};
      }
      else {
        return info1.intersect(this);
      }
    }
    else if (kind == TYPE_OR_SUPERTYPE) {
      if (info1.kind == TYPE_STRICTLY) {
        if (info1.type.isAssignableFrom(type)) return new ExpectedTypeInfoImpl[] {info1};
      }
      else if (info1.kind == TYPE_OR_SUBTYPE) {
        PsiType otherType = info1.type;
        if (otherType.isAssignableFrom(type)) return new ExpectedTypeInfoImpl[] {this};
      }
      else if (info1.kind == TYPE_OR_SUPERTYPE) {
        PsiType otherType = info1.type;
        if (type.isAssignableFrom(otherType)) return new ExpectedTypeInfoImpl[] {this};
        else if (otherType.isAssignableFrom(type)) return new ExpectedTypeInfoImpl[] {info1};
      }
      else {
        return info1.intersect(this);
      }
    }


    //todo: the following cases are not implemented: SUPERxSUB, SUBxSUPER

    return ExpectedTypeInfo.EMPTY_ARRAY;
  }
}