/*
    * Licensed to the Apache Software Foundation (ASF) under one or more
    * contributor license agreements.  See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * The ASF licenses this file to You 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 org.apache.bcel.classfile;
  
  import java.io.DataInput;
  import java.io.DataOutputStream;
  import java.io.IOException;
  import java.util.Iterator;
  import java.util.stream.Stream;
  
  import org.apache.bcel.Const;
  
  /**
   * This class represents a BootstrapMethods attribute.
   *
   * @see <a href="https://docs.oracle.com/javase/specs/jvms/se8/html/jvms-4.html#jvms-4.7.23"> The class File Format :
   *      The BootstrapMethods Attribute</a>
   * @since 6.0
   */
  public class BootstrapMethods extends Attribute implements Iterable<BootstrapMethod> {
  
      private BootstrapMethod[] bootstrapMethods; // TODO this could be made final (setter is not used)
  
      /**
       * Initialize from another object. Note that both objects use the same references (shallow copy). Use clone() for a
       * physical copy.
       *
       * @param c Source to copy.
       */
      public BootstrapMethods(final BootstrapMethods c) {
          this(c.getNameIndex(), c.getLength(), c.getBootstrapMethods(), c.getConstantPool());
      }
  
      /**
       * @param nameIndex Index in constant pool to CONSTANT_Utf8
       * @param length Content length in bytes
       * @param bootstrapMethods array of bootstrap methods
       * @param constantPool Array of constants
       */
      public BootstrapMethods(final int nameIndex, final int length, final BootstrapMethod[] bootstrapMethods, final ConstantPool constantPool) {
          super(Const.ATTR_BOOTSTRAP_METHODS, nameIndex, length, constantPool);
          setBootstrapMethods(bootstrapMethods);
      }
  
      /**
       * Constructs object from Input stream.
       *
       * @param nameIndex Index in constant pool to CONSTANT_Utf8
       * @param length Content length in bytes
       * @param input Input stream
       * @param constantPool Array of constants
       * @throws IOException if an I/O error occurs.
       */
      BootstrapMethods(final int nameIndex, final int length, final DataInput input, final ConstantPool constantPool) throws IOException {
          this(nameIndex, length, (BootstrapMethod[]) null, constantPool);
  
          final int numBootstrapMethods = input.readUnsignedShort();
          bootstrapMethods = new BootstrapMethod[numBootstrapMethods];
          for (int i = 0; i < numBootstrapMethods; i++) {
              bootstrapMethods[i] = new BootstrapMethod(input);
          }
      }
  
      /**
       * @param v Visitor object
       */
      @Override
      public void accept(final Visitor v) {
          v.visitBootstrapMethods(this);
      }
  
      /**
       * @return deep copy of this attribute
       */
      @Override
      public BootstrapMethods copy(final ConstantPool constantPool) {
          final BootstrapMethods c = (BootstrapMethods) clone();
          c.bootstrapMethods = new BootstrapMethod[bootstrapMethods.length];
  
          for (int i = 0; i < bootstrapMethods.length; i++) {
              c.bootstrapMethods[i] = bootstrapMethods[i].copy();
          }
          c.setConstantPool(constantPool);
          return c;
     }
 
     /**
      * Dump bootstrap methods attribute to file stream in binary format.
      *
      * @param file Output file stream
      * @throws IOException if an I/O error occurs.
      */
     @Override
     public final void dump(final DataOutputStream file) throws IOException {
         super.dump(file);
 
         file.writeShort(bootstrapMethods.length);
         for (final BootstrapMethod bootstrapMethod : bootstrapMethods) {
             bootstrapMethod.dump(file);
         }
     }
 
     /**
      * @return array of bootstrap method "records"
      */
     public final BootstrapMethod[] getBootstrapMethods() {
         return bootstrapMethods;
     }
 
     @Override
     public Iterator<BootstrapMethod> iterator() {
         return Stream.of(bootstrapMethods).iterator();
     }
 
     /**
      * @param bootstrapMethods the array of bootstrap methods
      */
     public final void setBootstrapMethods(final BootstrapMethod[] bootstrapMethods) {
         this.bootstrapMethods = bootstrapMethods != null ? bootstrapMethods : BootstrapMethod.EMPTY_ARRAY;
     }
 
     /**
      * @return String representation.
      */
     @Override
     public final String toString() {
         final StringBuilder buf = new StringBuilder();
         buf.append("BootstrapMethods(");
         buf.append(bootstrapMethods.length);
         buf.append("):");
         for (int i = 0; i < bootstrapMethods.length; i++) {
             buf.append("\n");
             final int start = buf.length();
             buf.append("  ").append(i).append(": ");
             final int indentCount = buf.length() - start;
             final String[] lines = bootstrapMethods[i].toString(super.getConstantPool()).split("\\r?\\n");
             buf.append(lines[0]);
             for (int j = 1; j < lines.length; j++) {
                 buf.append("\n").append("          ", 0, indentCount).append(lines[j]);
             }
         }
         return buf.toString();
     }
 }