/*
    * 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
    *
   *   https://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.Arrays;
  import java.util.Iterator;
  import java.util.stream.Stream;
  
  import org.apache.bcel.Const;
  import org.apache.bcel.util.Args;
  
  // The new table is used when generic types are about...
  
  //LocalVariableTable_attribute {
  //       u2 attribute_name_index;
  //       u4 attribute_length;
  //       u2 local_variable_table_length;
  //       {  u2 start_pc;
  //          u2 length;
  //          u2 name_index;
  //          u2 descriptor_index;
  //          u2 index;
  //       } local_variable_table[local_variable_table_length];
  //     }
  
  //LocalVariableTypeTable_attribute {
  //    u2 attribute_name_index;
  //    u4 attribute_length;
  //    u2 local_variable_type_table_length;
  //    {
  //      u2 start_pc;
  //      u2 length;
  //      u2 name_index;
  //      u2 signature_index;
  //      u2 index;
  //    } localVariableTypeTable[local_variable_type_table_length];
  //  }
  // J5TODO: Needs some testing !
  
  /**
   * Represents the LocalVariableTypeTable attribute.
   *
   * @since 6.0
   */
  public class LocalVariableTypeTable extends Attribute implements Iterable<LocalVariable> {
  
      private static final LocalVariable[] EMPTY_ARRAY = {};
  
      private LocalVariable[] localVariableTypeTable; // variables
  
      LocalVariableTypeTable(final int nameIdx, final int len, final DataInput input, final ConstantPool cpool) throws IOException {
          this(nameIdx, len, (LocalVariable[]) null, cpool);
          final int localVariableTypeTableLength = input.readUnsignedShort();
          localVariableTypeTable = new LocalVariable[localVariableTypeTableLength];
          for (int i = 0; i < localVariableTypeTableLength; i++) {
              localVariableTypeTable[i] = new LocalVariable(input, cpool);
          }
      }
  
      public LocalVariableTypeTable(final int nameIndex, final int length, final LocalVariable[] localVariableTypeTable, final ConstantPool constantPool) {
          super(Const.ATTR_LOCAL_VARIABLE_TYPE_TABLE, nameIndex, length, constantPool);
          this.localVariableTypeTable = localVariableTypeTable != null ? localVariableTypeTable : LocalVariable.EMPTY_ARRAY;
          Args.requireU2(this.localVariableTypeTable.length, "localVariableTypeTable.length");
      }
  
      public LocalVariableTypeTable(final LocalVariableTypeTable c) {
          this(c.getNameIndex(), c.getLength(), c.getLocalVariableTypeTable(), c.getConstantPool());
      }
  
      @Override
      public void accept(final Visitor v) {
          v.visitLocalVariableTypeTable(this);
      }
  
      /**
       * @return deep copy of this attribute.
       */
      @Override
      public Attribute copy(final ConstantPool constantPool) {
         final LocalVariableTypeTable c = (LocalVariableTypeTable) clone();
         c.localVariableTypeTable = new LocalVariable[localVariableTypeTable.length];
         Arrays.setAll(c.localVariableTypeTable, i -> localVariableTypeTable[i].copy());
         c.setConstantPool(constantPool);
         return c;
     }
 
     @Override
     public final void dump(final DataOutputStream file) throws IOException {
         super.dump(file);
         file.writeShort(localVariableTypeTable.length);
         for (final LocalVariable variable : localVariableTypeTable) {
             variable.dump(file);
         }
     }
 
     public final LocalVariable getLocalVariable(final int index) {
         for (final LocalVariable variable : localVariableTypeTable) {
             if (variable.getIndex() == index) {
                 return variable;
             }
         }
         return null;
     }
 
     public final LocalVariable[] getLocalVariableTypeTable() {
         return localVariableTypeTable;
     }
 
     public final int getTableLength() {
         return localVariableTypeTable == null ? 0 : localVariableTypeTable.length;
     }
 
     @Override
     public Iterator<LocalVariable> iterator() {
         return Stream.of(localVariableTypeTable).iterator();
     }
 
     public final void setLocalVariableTable(final LocalVariable[] localVariableTable) {
         this.localVariableTypeTable = localVariableTable != null ? localVariableTable : EMPTY_ARRAY;
     }
 
     /**
      * @return String representation.
      */
     @Override
     public final String toString() {
         final StringBuilder buf = new StringBuilder();
         for (int i = 0; i < localVariableTypeTable.length; i++) {
             buf.append(localVariableTypeTable[i].toStringShared(true));
             if (i < localVariableTypeTable.length - 1) {
                 buf.append('\n');
             }
         }
         return buf.toString();
     }
 }