/*
 * 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.mongodb.commands.signatures.admin;

import com.eightkdata.mongowp.bson.BsonDocument;
import com.eightkdata.mongowp.exceptions.BadValueException;
import com.eightkdata.mongowp.exceptions.NoSuchKeyException;
import com.eightkdata.mongowp.exceptions.TypesMismatchException;
import com.eightkdata.mongowp.fields.DocField;
import com.eightkdata.mongowp.fields.IntField;
import com.eightkdata.mongowp.fields.StringField;
import com.eightkdata.mongowp.server.api.impl.AbstractCommand;
import com.eightkdata.mongowp.utils.BsonDocumentBuilder;
import com.eightkdata.mongowp.utils.BsonReaderTool;
import com.google.common.collect.ImmutableList;
import com.torodb.mongodb.commands.pojos.index.IndexOptions;
import com.torodb.mongodb.commands.signatures.admin.DropIndexesCommand.DropIndexesArgument;
import com.torodb.mongodb.commands.signatures.admin.DropIndexesCommand.DropIndexesResult;

import java.util.List;

import javax.annotation.Nullable;

public class DropIndexesCommand
    extends AbstractCommand<DropIndexesArgument, DropIndexesResult> {

  private static final String COMMAND_NAME = "dropIndexes";

  public static final DropIndexesCommand INSTANCE = new DropIndexesCommand();

  private DropIndexesCommand() {
    super(COMMAND_NAME);
  }

  protected DropIndexesCommand(String commandName) {
    super(commandName);
  }

  @Override
  public Class<? extends DropIndexesArgument> getArgClass() {
    return DropIndexesArgument.class;
  }

  @Override
  public DropIndexesArgument unmarshallArg(BsonDocument requestDoc, String aliasedAs)
      throws TypesMismatchException, NoSuchKeyException, BadValueException {
    return DropIndexesArgument.unmarshall(requestDoc, aliasedAs);
  }

  @Override
  public BsonDocument marshallArg(DropIndexesArgument request, String aliasedAs) {
    return request.marshall(aliasedAs);
  }

  @Override
  public Class<? extends DropIndexesResult> getResultClass() {
    return DropIndexesResult.class;
  }

  @Override
  public BsonDocument marshallResult(DropIndexesResult reply) {
    return reply.marshall();
  }

  @Override
  public DropIndexesResult unmarshallResult(BsonDocument replyDoc) throws TypesMismatchException,
      NoSuchKeyException {
    return DropIndexesResult.unmarshall(replyDoc);
  }

  public static class DropIndexesArgument {

    private static final StringField INDEX_NAME_FIELD = new StringField("index");
    private static final DocField INDEX_KEYS_FIELD = new DocField("index");

    private final String collection;
    private final String indexToDrop;
    private final ImmutableList<IndexOptions.Key> keys;
    private final boolean dropAllIndexes;
    private final boolean dropByKeys;

    public DropIndexesArgument(String collection, String indexToDrop) {
      this.collection = collection;
      this.indexToDrop = indexToDrop;
      this.keys = null;
      dropAllIndexes = indexToDrop.equals("*");
      dropByKeys = false;
    }

    public DropIndexesArgument(String collection, ImmutableList<IndexOptions.Key> keys) {
      this.collection = collection;
      this.indexToDrop = null;
      this.keys = keys;
      dropAllIndexes = false;
      dropByKeys = true;
    }

    public String getCollection() {
      return collection;
    }

    @Nullable
    public String getIndexToDrop() {
      return indexToDrop;
    }

    @Nullable
    public ImmutableList<IndexOptions.Key> getKeys() {
      return keys;
    }

    public boolean isDropAllIndexes() {
      return dropAllIndexes;
    }

    public boolean isDropByKeys() {
      return dropByKeys;
    }

    private BsonDocument marshall(String aliasedAs) {
      StringField collectionField = new StringField(aliasedAs);
      return new BsonDocumentBuilder()
          .append(collectionField, collection)
          .append(INDEX_NAME_FIELD, indexToDrop)
          .build();
    }

    private static DropIndexesArgument unmarshall(BsonDocument requestDoc, String commandName)
        throws TypesMismatchException, NoSuchKeyException, BadValueException {
      String collection = BsonReaderTool.getString(requestDoc, commandName);
      try {
        String indexToDrop = BsonReaderTool.getString(requestDoc, INDEX_NAME_FIELD);
        return new DropIndexesArgument(collection, indexToDrop);
      } catch (TypesMismatchException typesMismatchException) {
        BsonDocument indexByKeysToDrop = BsonReaderTool.getDocument(requestDoc, INDEX_KEYS_FIELD);
        List<IndexOptions.Key> indexKeys = IndexOptions.unmarshllKeys(indexByKeysToDrop);
        return new DropIndexesArgument(collection, ImmutableList.copyOf(indexKeys));
      }
    }
  }

  public static class DropIndexesResult {

    private static final IntField N_INDEXES_WAS_FIELD = new IntField("nIndexesWas");

    private final int nIndexesWas;

    public DropIndexesResult(
        int nIndexesWas) {
      this.nIndexesWas = nIndexesWas;
    }

    public int getNIndexesWas() {
      return nIndexesWas;
    }

    private static DropIndexesResult unmarshall(BsonDocument replyDoc) 
        throws TypesMismatchException, NoSuchKeyException {
      int nIndexesWas = BsonReaderTool.getInteger(replyDoc, N_INDEXES_WAS_FIELD);
      return new DropIndexesResult(nIndexesWas);
    }

    private BsonDocument marshall() {
      BsonDocumentBuilder builder = new BsonDocumentBuilder();
      builder.append(N_INDEXES_WAS_FIELD, nIndexesWas);
      return builder.build();
    }

  }

}