/*
 *  ******************************************************************************
 *  *
 *  *
 *  * This program and the accompanying materials are made available under the
 *  * terms of the Apache License, Version 2.0 which is available at
 *  * https://www.apache.org/licenses/LICENSE-2.0.
 *  *
 *  *  See the NOTICE file distributed with this work for additional
 *  *  information regarding copyright ownership.
 *  * 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.
 *  *
 *  * SPDX-License-Identifier: Apache-2.0
 *  *****************************************************************************
 */

package org.datavec.api.io;

import java.io.ByteArrayInputStream;
import java.io.DataInput;
import java.io.DataInputStream;

public class DataInputBuffer extends DataInputStream {
    private static class Buffer extends ByteArrayInputStream {
        public Buffer() {
            super(new byte[] {});
        }

        public void reset(byte[] input, int start, int length) {
            this.buf = input;
            this.count = start + length;
            this.mark = start;
            this.pos = start;
        }

        public byte[] getData() {
            return buf;
        }

        public int getPosition() {
            return pos;
        }

        public int getLength() {
            return count;
        }
    }

    private Buffer buffer;

    /** Constructs a new empty buffer. */
    public DataInputBuffer() {
        this(new Buffer());
    }

    private DataInputBuffer(Buffer buffer) {
        super(buffer);
        this.buffer = buffer;
    }

    /** Resets the data that the buffer reads. */
    public void reset(byte[] input, int length) {
        buffer.reset(input, 0, length);
    }

    /** Resets the data that the buffer reads. */
    public void reset(byte[] input, int start, int length) {
        buffer.reset(input, start, length);
    }

    public byte[] getData() {
        return buffer.getData();
    }

    /** Returns the current position in the input. */
    public int getPosition() {
        return buffer.getPosition();
    }

    /** Returns the length of the input. */
    public int getLength() {
        return buffer.getLength();
    }

}
