/*
 * Copyright DataStax, Inc.
 *
 * Licensed 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 com.datastax.oss.protocol.internal.request;

import static com.datastax.oss.protocol.internal.ProtocolConstants.Version.V5;

import com.datastax.oss.protocol.internal.Message;
import com.datastax.oss.protocol.internal.PrimitiveCodec;
import com.datastax.oss.protocol.internal.PrimitiveSizes;
import com.datastax.oss.protocol.internal.ProtocolConstants;

public class Prepare extends Message {
  public final String cqlQuery;
  public final String keyspace;

  public Prepare(String cqlQuery, String keyspace) {
    super(false, ProtocolConstants.Opcode.PREPARE);
    this.cqlQuery = cqlQuery;
    this.keyspace = keyspace;
  }

  public Prepare(String cqlQuery) {
    this(cqlQuery, null);
  }

  @Override
  public String toString() {
    return "PREPARE(" + cqlQuery + ", " + keyspace + ')';
  }

  public static class Codec extends Message.Codec {
    public Codec(int protocolVersion) {
      super(ProtocolConstants.Opcode.PREPARE, protocolVersion);
    }

    @Override
    public <B> void encode(B dest, Message message, PrimitiveCodec<B> encoder) {
      Prepare prepare = (Prepare) message;
      encoder.writeLongString(prepare.cqlQuery, dest);
      if (protocolVersion >= V5) {
        // There is only one PREPARE flag for now, so hard-code for simplicity:
        encoder.writeInt((prepare.keyspace == null) ? 0x00 : 0x01, dest);
        if (prepare.keyspace != null) {
          encoder.writeString(prepare.keyspace, dest);
        }
      }
    }

    @Override
    public int encodedSize(Message message) {
      Prepare prepare = (Prepare) message;
      int size = PrimitiveSizes.sizeOfLongString(prepare.cqlQuery);
      if (protocolVersion >= V5) {
        size += PrimitiveSizes.INT; // flags
        if (prepare.keyspace != null) {
          size += PrimitiveSizes.sizeOfString(prepare.keyspace);
        }
      }
      return size;
    }

    @Override
    public <B> Message decode(B source, PrimitiveCodec<B> decoder) {
      String cqlQuery = decoder.readLongString(source);
      String keyspace = null;
      if (protocolVersion >= V5) {
        int flags = decoder.readInt(source);
        if ((flags & 0x01) == 0x01) {
          keyspace = decoder.readString(source);
        }
      }
      return new Prepare(cqlQuery, keyspace);
    }
  }
}