/*
 * 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.geode.cache.query.internal;

import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Comparator;
import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Set;
import java.util.SortedSet;

import org.apache.geode.DataSerializer;
import org.apache.geode.cache.query.SelectResults;
import org.apache.geode.cache.query.Struct;

import org.apache.geode.cache.query.internal.types.CollectionTypeImpl;
import org.apache.geode.cache.query.internal.types.StructTypeImpl;
import org.apache.geode.cache.query.types.CollectionType;
import org.apache.geode.cache.query.types.ObjectType;
import org.apache.geode.internal.DataSerializableFixedID;
import org.apache.geode.internal.Version;
import org.apache.geode.internal.i18n.LocalizedStrings;

public class LinkedStructSet extends LinkedHashSet<Struct>
    implements SelectResults<Struct>, Ordered, DataSerializableFixedID {

  private static final long serialVersionUID = -1687142950781718156L;

  protected StructTypeImpl structType;

  /**
   * Holds value of property modifiable.
   */
  private boolean modifiable = true;

  /** Creates a new instance of StructSet */
  public LinkedStructSet() {};

  /** Creates a new instance of StructSet */
  public LinkedStructSet(StructTypeImpl structType) {
    if (structType == null) {
      throw new IllegalArgumentException(
          LocalizedStrings.SortedStructSet_STRUCTTYPE_MUST_NOT_BE_NULL.toLocalizedString());
    }
    this.structType = structType;
  }

  @Override
  public boolean equals(Object other) {
    if (!(other instanceof SortedStructSet)) {
      return false;
    }
    if (!this.structType.equals(((SortedStructSet) other).structType)) {
      return false;
    }
    return super.equals(other);
  }

  /** Add a Struct */
  @Override
  public boolean add(Struct obj) {
    if (!(obj instanceof StructImpl)) {
      throw new IllegalArgumentException(
          LocalizedStrings.SortedStructSet_THIS_SET_ONLY_ACCEPTS_STRUCTIMPL.toLocalizedString());
    }
    StructImpl s = (StructImpl) obj;
    if (!s.getStructType().equals(this.structType)) {
      throw new IllegalArgumentException(
          LocalizedStrings.SortedStructSet_OBJ_DOES_NOT_HAVE_THE_SAME_STRUCTTYPE
              .toLocalizedString());
    }
    // return addFieldValues(s.getFieldValues());
    return super.add(s);
  }

  /**
   * For internal use. Just add the Object[] values for a struct with same type
   * 
   * public boolean addFieldValues(Object[] fieldValues) { //return super.add(fieldValues);
   * StructImpl s = new StructImpl(this.structType, fieldValues); return super.add(s); }
   */

  /** Does this set contain specified struct? */
  @Override
  public boolean contains(Object obj) {
    if (!(obj instanceof Struct)) {
      return false;
    }
    Struct s = (Struct) obj;
    if (!this.structType.equals(StructTypeImpl.typeFromStruct(s))) {
      return false;
    }
    return contains(s);
    // return containsFieldValues(s.getFieldValues());
  }

  /**
   * Does this set contain a Struct of the correct type with the specified values?
   * 
   * public boolean containsFieldValues(Object[] fieldValues) { return super.contains(fieldValues);
   * }
   */

  /** Remove the specified Struct */
  @Override
  public boolean remove(Object o) {
    if (!(o instanceof Struct)) {
      return false;
    }
    Struct s = (Struct) o;
    if (!this.structType.equals(StructTypeImpl.typeFromStruct(s))) {
      return false;
    }
    return remove(s);
    // return removeFieldValues(s.getFieldValues());
  }

  /**
   * Remove the field values from a struct of the correct type public boolean
   * removeFieldValues(Object[] fieldValues) { return super.remove(fieldValues); }
   */

  // downcast StructSets to call more efficient methods
  @Override
  public boolean addAll(Collection c) {
    // if (c instanceof StructSet) {
    // return addAll((StructSet)c);
    // }
    return super.addAll(c);
  }

  @Override
  public boolean removeAll(Collection c) {
    // if (c instanceof StructSet) {
    // return removeAll((StructSet)c);
    // }
    return super.removeAll(c);
  }

  @Override
  public boolean retainAll(Collection c) {
    // if (c instanceof StructSet) {
    // return retainAll((StructSet)c);
    // }
    return super.retainAll(c);
  }

  // public boolean addAll(StructSet ss) {
  // boolean modified = false;
  // if (!this.structType.equals(ss.structType)) { throw new
  // IllegalArgumentException(LocalizedStrings.SortedStructSet_TYPES_DONT_MATCH.toLocalizedString());
  // }
  // for (Iterator itr = ss.fieldValuesIterator(); itr.hasNext();) {
  // Struct vals = (Struct) itr.next();
  // if (super.add(vals)) {
  // modified = true;
  // }
  // }
  // return modified;
  // }

  // public boolean removeAll(StructSet ss) {
  // boolean modified = false;
  // if (!this.structType.equals(ss.structType)) { return false; // nothing
  // // modified
  // }
  // for (Iterator itr = ss.fieldValuesIterator(); itr.hasNext();) {
  // Struct vals = (Struct) itr.next();
  // if (super.remove(vals)) {
  // modified = true;
  // }
  // }
  // return modified;
  // }
  //
  // public boolean retainAll(StructSet ss) {
  // if (!this.structType.equals(ss.structType)) {
  // if (isEmpty()) {
  // return false; // nothing modified
  // }
  // else {
  // clear();
  // return true; // nothing retained in receiver collection
  // }
  // }
  // boolean changed = false;
  // int size = size();
  // Iterator it;
  // it = fieldValuesIterator();
  // while (size-- > 0) {
  // Struct val = (Struct) it.next();
  // //if (!ss.containsFieldValues(vals)) {
  // if (!ss.contains(val)) {
  // it.remove();
  // changed = true;
  // }
  // }
  // return changed;
  // }

  /** Returns an Iterator over the Structs in this set */
  @Override
  public Iterator iterator() {
    return new StructIterator(fieldValuesIterator());
  }

  /** Returns an iterator over the fieldValues Object[] instances */
  public Iterator fieldValuesIterator() {
    return super.iterator();
  }

  public CollectionType getCollectionType() {
    return new CollectionTypeImpl(Ordered.class, this.structType);
  }

  // note: this method is dangerous in that it could result in undefined
  // behavior if the new struct type is not compatible with the data.
  // For now just trust that the application knows what it is doing if it
  // is overriding the element type in a set of structs
  public void setElementType(ObjectType elementType) {
    if (!(elementType instanceof StructTypeImpl)) {
      throw new IllegalArgumentException(
          LocalizedStrings.SortedStructSet_ELEMENT_TYPE_MUST_BE_STRUCT.toLocalizedString());
    }
    this.structType = (StructTypeImpl) elementType;
  }

  public List asList() {
    return new ArrayList(this);
  }

  public Set asSet() {
    return this;
  }

  /**
   * Getter for property modifiable.
   * 
   * @return Value of property modifiable.
   */
  public boolean isModifiable() {
    return this.modifiable;
  }

  public int occurrences(Struct element) {
    return contains(element) ? 1 : 0;
  }

  /**
   * Setter for property modifiable.
   * 
   * @param modifiable New value of property modifiable.
   */
  public void setModifiable(boolean modifiable) {
    this.modifiable = modifiable;
  }

  @Override
  public String toString() {
    StringBuffer buf = new StringBuffer();
    buf.append("[");
    Iterator i = iterator();
    boolean hasNext = i.hasNext();
    while (hasNext) {
      Object o = i.next();
      buf.append(o == this ? "(this Collection)" : String.valueOf(o));
      hasNext = i.hasNext();
      if (hasNext)
        buf.append(",\n ");
    }
    buf.append("]");
    return buf.toString();
  }

  /**
   * Iterator wrapper to construct Structs on demand.
   */
  static private class StructIterator implements Iterator {

    private final Iterator itr;

    StructIterator(Iterator itr) {
      this.itr = itr;
    }

    public boolean hasNext() {
      return this.itr.hasNext();
    }

    public Object next() {
      return this.itr.next();
    }

    public void remove() {
      this.itr.remove();
    }
  }

  public void fromData(DataInput in) throws IOException, ClassNotFoundException {
    this.modifiable = in.readBoolean();
    int size = in.readInt();
    this.structType = (StructTypeImpl) DataSerializer.readObject(in);
    for (int j = size; j > 0; j--) {
      Object[] fieldValues = DataSerializer.readObject(in);
      this.add(new StructImpl(this.structType, fieldValues));
    }
  }

  public int getDSFID() {

    return LINKED_STRUCTSET;
  }

  public void toData(DataOutput out) throws IOException {
    // how do we serialize the comparator?
    out.writeBoolean(this.modifiable);
    out.writeInt(this.size());
    DataSerializer.writeObject(this.structType, out);
    for (Iterator<Struct> i = this.iterator(); i.hasNext();) {
      Struct struct = i.next();
      DataSerializer.writeObject(struct.getFieldValues(), out);
    }
  }

  @Override
  public Version[] getSerializationVersions() {
    return null;
  }

  @Override
  public Comparator comparator() {
    return null;
  }

  @Override
  public boolean dataPreordered() {
    return true;
  }

}
