/*
 * SPDX-License-Identifier: Apache-2.0
 *
 * The OpenSearch Contributors require contributions made to
 * this file be licensed under the Apache-2.0 license or a
 * compatible open source license.
 */

/*
 * Licensed to Elasticsearch under one or more contributor
 * license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright
 * ownership. Elasticsearch 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.
 */

/*
 * Modifications Copyright OpenSearch Contributors. See
 * GitHub history for details.
 */

package org.opensearch.http.netty4;

import org.opensearch.ExceptionsHelper;
import org.opensearch.core.common.unit.ByteSizeValue;

import java.util.List;

import io.netty.channel.ChannelHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.MessageToMessageDecoder;
import io.netty.handler.codec.http.FullHttpRequest;
import io.netty.handler.codec.http.TooLongHttpLineException;

@ChannelHandler.Sharable
class Netty4Http3RequestCreator extends MessageToMessageDecoder<FullHttpRequest> {
    private final ByteSizeValue maxInitialLineLength;

    Netty4Http3RequestCreator(ByteSizeValue maxInitialLineLength) {
        this.maxInitialLineLength = maxInitialLineLength;
    }

    @Override
    protected void decode(ChannelHandlerContext ctx, FullHttpRequest msg, List<Object> out) {
        if (msg.decoderResult().isFailure()) {
            final Throwable cause = msg.decoderResult().cause();
            final Exception nonError;
            if (cause instanceof Error) {
                ExceptionsHelper.maybeDieOnAnotherThread(cause);
                nonError = new Exception(cause);
            } else {
                nonError = (Exception) cause;
            }
            out.add(new Netty4HttpRequest(msg.retain(), nonError));
        } else {
            // The HTTP/3 implementation in Netty does not validate Request URI length, manually
            // applying the validation rules here.
            if (msg.uri().length() > maxInitialLineLength.bytesAsInt()) {
                out.add(
                    new Netty4HttpRequest(
                        msg.retain(),
                        new TooLongHttpLineException("An HTTP line is larger than " + maxInitialLineLength.bytesAsInt() + " bytes.")
                    )
                );
            } else {
                out.add(new Netty4HttpRequest(msg.retain()));
            }
        }
    }
}
