/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF 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
 *
 *      https://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 org.apache.commons.io.input;

import static org.junit.jupiter.api.Assertions.assertSame;

import java.io.IOException;
import java.io.Reader;
import java.nio.CharBuffer;

import org.junit.jupiter.api.Test;

/**
 * Tests {@link ProxyReader}.
 */
class ProxyReaderTest {

    /** Custom NullReader implementation. */
    private static final class CustomNullReader extends NullReader {

        CustomNullReader(final int len) {
            super(len);
        }

        @Override
        public int read(final char[] chars) throws IOException {
            return chars == null ? 0 : super.read(chars);
        }

        @Override
        public int read(final char[] chars, final int offset, final int length) throws IOException {
            return chars == null ? 0 : super.read(chars, offset, length);
        }

        @Override
        public int read(final CharBuffer target) throws IOException {
            return target == null ? 0 : super.read(target);
        }
    }

    /** ProxyReader implementation. */
    private static final class ProxyReaderImpl extends ProxyReader {

        ProxyReaderImpl(final Reader proxy) {
            super(proxy);
        }
    }

    @Test
    void testNullCharArray() throws Exception {
        try (ProxyReader proxy = new ProxyReaderImpl(new CustomNullReader(0))) {
            proxy.read((char[]) null);
            proxy.read(null, 0, 0);
        }
    }

    @Test
    void testNullCharBuffer() throws Exception {
        try (ProxyReader proxy = new ProxyReaderImpl(new CustomNullReader(0))) {
            proxy.read((CharBuffer) null);
        }
    }

    @Test
    void testSetReference() throws Exception {
        try (CustomNullReader wrapped = new CustomNullReader(0); ProxyReader proxy = new ProxyReaderImpl(wrapped)) {
            assertSame(wrapped, proxy.unwrap());
            proxy.setReference(NullReader.INSTANCE);
            assertSame(NullReader.INSTANCE, proxy.unwrap());
        }
    }

    @Test
    void testUnwrap() throws Exception {
        try (CustomNullReader wrapped = new CustomNullReader(0); ProxyReader proxy = new ProxyReaderImpl(wrapped)) {
            assertSame(wrapped, proxy.unwrap());
        }
    }
}
