/*
 * Copyright (C) 2014 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 dagger.internal.codegen.writer;

import com.google.common.base.Objects;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableSet;
import java.io.IOException;
import java.util.Iterator;
import java.util.Set;

import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Verify.verify;

public final class ParameterizedTypeName implements TypeName {
  private final ClassName type;
  private final ImmutableList<TypeName> parameters;

  ParameterizedTypeName(ClassName type, Iterable<? extends TypeName> parameters) {
    this.type = type;
    this.parameters = ImmutableList.<TypeName>copyOf(parameters);
  }
  
  public ClassName type() {
    return type;
  }
  
  public ImmutableList<TypeName> parameters() {
    return parameters;
  }

  @Override
  public Set<ClassName> referencedClasses() {
    ImmutableSet.Builder<ClassName> builder = new ImmutableSet.Builder<ClassName>()
        .add(type);
    for (TypeName parameter : parameters) {
      builder.addAll(parameter.referencedClasses());
    }
    return builder.build();
  }

  @Override
  public Appendable write(Appendable appendable, Context context) throws IOException {
    appendable.append(context.sourceReferenceForClassName(type));
    Iterator<? extends TypeName> parameterIterator = parameters.iterator();
    verify(parameterIterator.hasNext(), type.toString());
    appendable.append('<');
    parameterIterator.next().write(appendable, context);
    while (parameterIterator.hasNext()) {
      appendable.append(", ");
      parameterIterator.next().write(appendable, context);
    }
    appendable.append('>');
    return appendable;
  }

  @Override
  public boolean equals(Object obj) {
    if (obj instanceof ParameterizedTypeName) {
      ParameterizedTypeName that = (ParameterizedTypeName) obj;
      return this.type.equals(that.type)
          && this.parameters.equals(that.parameters);
    } else {
      return false;
    }
  }

  @Override
  public int hashCode() {
    return Objects.hashCode(type, parameters);
  }

  @Override
  public String toString() {
    return Writables.writeToString(this);
  }

  public static ParameterizedTypeName create(ClassName className,
      TypeName... parameters) {
    return new ParameterizedTypeName(className, ImmutableList.copyOf(parameters));
  }

  public static ParameterizedTypeName create(ClassName className,
      Iterable<? extends TypeName> parameters) {
    return new ParameterizedTypeName(className, ImmutableList.copyOf(parameters));
  }

  public static ParameterizedTypeName create(Class<?> parameterizedClass,
      TypeName... parameters) {
    checkArgument(parameterizedClass.getTypeParameters().length == parameters.length);
    return new ParameterizedTypeName(ClassName.fromClass(parameterizedClass),
        ImmutableList.copyOf(parameters));
  }
}