/*
 * Copyright (c) 2015, 2017, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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 General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 */

package jdk.incubator.http.internal.frame;

import jdk.incubator.http.internal.common.Utils;

import java.nio.ByteBuffer;
import java.util.List;

public class DataFrame extends Http2Frame {

    public static final int TYPE = 0x0;

    // Flags
    public static final int END_STREAM = 0x1;
    public static final int PADDED = 0x8;

    private int padLength;
    private final List<ByteBuffer> data;
    private final int dataLength;

    public DataFrame(int streamid, int flags, ByteBuffer data) {
        this(streamid, flags, List.of(data));
    }

    public DataFrame(int streamid, int flags, List<ByteBuffer> data) {
        super(streamid, flags);
        this.data = data;
        this.dataLength = Utils.remaining(data, Integer.MAX_VALUE);
    }

    public DataFrame(int streamid, int flags, List<ByteBuffer> data, int padLength) {
        this(streamid, flags, data);
        if (padLength > 0) {
            setPadLength(padLength);
        }
    }

    @Override
    public int type() {
        return TYPE;
    }

    @Override
    int length() {
        return dataLength + (((flags & PADDED) != 0) ? (padLength + 1) : 0);
    }

    @Override
    public String flagAsString(int flag) {
        switch (flag) {
        case END_STREAM:
            return "END_STREAM";
        case PADDED:
            return "PADDED";
        }
        return super.flagAsString(flag);
    }

    public List<ByteBuffer> getData() {
        return data;
    }

    public int getDataLength() {
        return dataLength;
    }

    int getPadLength() {
        return padLength;
    }

    public void setPadLength(int padLength) {
        this.padLength = padLength;
        flags |= PADDED;
    }

    public int payloadLength() {
        // RFC 7540 6.1:
        // The entire DATA frame payload is included in flow control,
        // including the Pad Length and Padding fields if present
        if ((flags & PADDED) != 0) {
            return dataLength + (1 + padLength);
        } else {
            return dataLength;
        }
    }


}