/*
 * ToroDB
 * Copyright © 2014 8Kdata Technology (www.8kdata.com)
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

package com.torodb.core.transaction.metainf;

import com.google.common.base.Preconditions;
import com.torodb.core.annotations.DoNotChange;
import com.torodb.core.transaction.metainf.ImmutableMetaIdentifiedDocPartIndex.Builder;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.function.BiConsumer;
import java.util.stream.IntStream;

/**
 *
 */
public class WrapperMutableMetaDocPartIndex extends AbstractMetaDocPartIndex implements
    MutableMetaDocPartIndex {

  /**
   * This table contains all fields contained by wrapper and all new fields
   */
  private final Map<String, ImmutableMetaDocPartIndexColumn> addedColumnsByIdentifier;
  /**
   * This list just contains the fields that have been added on this wrapper but not on the wrapped
   * object.
   */
  private final List<ImmutableMetaDocPartIndexColumn> addedColumns;
  @SuppressWarnings("checkstyle:LineLength")
  private final BiConsumer<WrapperMutableMetaDocPartIndex, ImmutableMetaIdentifiedDocPartIndex> changeConsumer;

  public WrapperMutableMetaDocPartIndex(
      boolean unique,
      BiConsumer<WrapperMutableMetaDocPartIndex,
      ImmutableMetaIdentifiedDocPartIndex> changeConsumer) {
    super(unique);
    addedColumnsByIdentifier = new HashMap<>();
    addedColumns = new ArrayList<>();
    this.changeConsumer = changeConsumer;
  }

  @Override
  public ImmutableMetaDocPartIndexColumn putMetaDocPartIndexColumn(int position, String identifier,
      FieldIndexOrdering ordering) throws
      IllegalArgumentException {
    if (getMetaDocPartIndexColumnByIdentifier(identifier) != null) {
      throw new IllegalArgumentException("There is another column with the identifier "
          + identifier);
    }
    if (getMetaDocPartIndexColumnByPosition(position) != null) {
      throw new IllegalArgumentException("There is another column with the position " + position);
    }

    ImmutableMetaDocPartIndexColumn newField = new ImmutableMetaDocPartIndexColumn(position,
        identifier, ordering);
    addedColumnsByIdentifier.put(identifier, newField);
    if (addedColumns.size() <= position) {
      IntStream.range(addedColumns.size(), position + 1)
          .forEach(index -> addedColumns.add(null));
    }
    addedColumns.set(position, newField);
    return newField;
  }

  @Override
  public ImmutableMetaDocPartIndexColumn addMetaDocPartIndexColumn(String identifier,
      FieldIndexOrdering ordering) throws
      IllegalArgumentException {
    if (getMetaDocPartIndexColumnByIdentifier(identifier) != null) {
      throw new IllegalArgumentException("There is another column with the identifier "
          + identifier);
    }

    ImmutableMetaDocPartIndexColumn newField = new ImmutableMetaDocPartIndexColumn(size(),
        identifier, ordering);
    addedColumnsByIdentifier.put(identifier, newField);
    addedColumns.add(newField);
    return newField;
  }

  @Override
  @DoNotChange
  public Iterable<ImmutableMetaDocPartIndexColumn> getAddedMetaDocPartIndexColumns() {
    return addedColumns;
  }

  @Override
  public ImmutableMetaIdentifiedDocPartIndex immutableCopy(String identifier) {
    Preconditions.checkArgument(addedColumnsByIdentifier.size() == addedColumns.size(),
        "Some columns are missing. Found %s but they should be %s",
        addedColumnsByIdentifier.size(), addedColumns.size());
    ImmutableMetaIdentifiedDocPartIndex.Builder builder = new Builder(identifier, isUnique());
    for (ImmutableMetaDocPartIndexColumn addedField : addedColumns) {
      builder.add(addedField);
    }
    ImmutableMetaIdentifiedDocPartIndex immutableIndex = builder.build();
    changeConsumer.accept(this, immutableIndex);
    return immutableIndex;
  }

  @Override
  public int size() {
    return addedColumnsByIdentifier.size();
  }

  @Override
  public Iterator<? extends ImmutableMetaDocPartIndexColumn> iteratorColumns() {
    return addedColumns.iterator();
  }

  @Override
  public ImmutableMetaDocPartIndexColumn getMetaDocPartIndexColumnByIdentifier(String columnName) {
    return addedColumnsByIdentifier.get(columnName);
  }

  @Override
  public MetaDocPartIndexColumn getMetaDocPartIndexColumnByPosition(int position) {
    if (position >= addedColumns.size()) {
      return null;
    }
    return addedColumns.get(position);
  }

  @Override
  public String toString() {
    return defautToString();
  }

}