/*
 * 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.assertEquals;
import static org.junit.jupiter.api.Assertions.assertFalse;
import static org.junit.jupiter.api.Assertions.assertThrows;
import static org.junit.jupiter.api.Assertions.assertTrue;

import java.io.IOException;
import java.io.InputStream;

import org.junit.jupiter.api.Test;
import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.MethodSource;

/**
 * Tests {@link MarkShieldInputStream}.
 */
class MarkShieldInputStreamTest {

    private static final class MarkTestableInputStream extends ProxyInputStream {
        int markcount;
        int readLimit;

        MarkTestableInputStream(final InputStream in) {
            super(in);
        }

        @SuppressWarnings("sync-override")
        @Override
        public void mark(final int readLimit) {
            // record that `mark` was called
            this.markcount++;
            this.readLimit = readLimit;
            // invoke on super
            super.mark(readLimit);
        }
    }

    @SuppressWarnings("resource")
    @ParameterizedTest
    @MethodSource(AbstractInputStreamTest.ARRAY_LENGTHS_NAME)
    void testAvailableAfterClose(final int len) throws Exception {
        final InputStream shadow;
        try (MarkTestableInputStream in = new MarkTestableInputStream(new NullInputStream(len, false, false));
                MarkShieldInputStream msis = new MarkShieldInputStream(in)) {
            assertEquals(len, in.available());
            shadow = in;
        }
        assertEquals(0, shadow.available());
    }

    @ParameterizedTest
    @MethodSource(AbstractInputStreamTest.ARRAY_LENGTHS_NAME)
    void testAvailableAfterOpen(final int len) throws Exception {
        try (MarkTestableInputStream in = new MarkTestableInputStream(new NullInputStream(len, false, false));
                MarkShieldInputStream msis = new MarkShieldInputStream(in)) {
            assertEquals(len, in.available());
        }
    }

    @SuppressWarnings("resource")
    @Test
    void testCloseHandleIOException() throws IOException {
        ProxyInputStreamTest.testCloseHandleIOException(new MarkShieldInputStream(new BrokenInputStream((Throwable) new IOException())));
    }

    @Test
    void testMarkIsNoOpWhenUnderlyingDoesNotSupport() throws IOException {
        try (MarkTestableInputStream in = new MarkTestableInputStream(new NullInputStream(64, false, false));
                MarkShieldInputStream msis = new MarkShieldInputStream(in)) {
            msis.mark(1024);
            assertEquals(0, in.markcount);
            assertEquals(0, in.readLimit);
        }
    }

    @Test
    void testMarkIsNoOpWhenUnderlyingSupports() throws IOException {
        try (MarkTestableInputStream in = new MarkTestableInputStream(new NullInputStream(64, true, false));
                MarkShieldInputStream msis = new MarkShieldInputStream(in)) {
            msis.mark(1024);
            assertEquals(0, in.markcount);
            assertEquals(0, in.readLimit);
        }
    }

    @Test
    void testMarkSupportedIsFalseWhenUnderlyingFalse() throws IOException {
        // test wrapping an underlying stream which does NOT support marking
        try (InputStream is = new NullInputStream(64, false, false)) {
            assertFalse(is.markSupported());
            try (MarkShieldInputStream msis = new MarkShieldInputStream(is)) {
                assertFalse(msis.markSupported());
            }
        }
    }

    @Test
    void testMarkSupportedIsFalseWhenUnderlyingTrue() throws IOException {
        // test wrapping an underlying stream which supports marking
        try (InputStream is = new NullInputStream(64, true, false)) {
            assertTrue(is.markSupported());
            try (MarkShieldInputStream msis = new MarkShieldInputStream(is)) {
                assertFalse(msis.markSupported());
            }
        }
    }

    @ParameterizedTest
    @MethodSource(AbstractInputStreamTest.ARRAY_LENGTHS_NAME)
    void testReadAfterClose(final int len) throws Exception {
        try (MarkTestableInputStream in = new MarkTestableInputStream(new NullInputStream(len, false, false));
                MarkShieldInputStream msis = new MarkShieldInputStream(in)) {
            assertEquals(len, in.available());
            in.close();
            assertThrows(IOException.class, in::read);
        }
    }

    @ParameterizedTest
    @MethodSource(AbstractInputStreamTest.ARRAY_LENGTHS_NAME)
    void testReadByteArrayAfterClose(final int len) throws Exception {
        try (MarkTestableInputStream in = new MarkTestableInputStream(new NullInputStream(len, false, false));
                MarkShieldInputStream msis = new MarkShieldInputStream(in)) {
            assertEquals(len, in.available());
            in.close();
            assertEquals(0, in.read(new byte[0]));
            assertThrows(IOException.class, () -> in.read(new byte[2]));
        }
    }

    @ParameterizedTest
    @MethodSource(AbstractInputStreamTest.ARRAY_LENGTHS_NAME)
    void testReadByteArrayIntIntAfterClose(final int len) throws Exception {
        try (MarkTestableInputStream in = new MarkTestableInputStream(new NullInputStream(len, false, false));
                MarkShieldInputStream msis = new MarkShieldInputStream(in)) {
            assertEquals(len, in.available());
            in.close();
            assertEquals(0, in.read(new byte[0], 0, 1));
            assertEquals(0, in.read(new byte[1], 0, 0));
            assertThrows(IOException.class, () -> in.read(new byte[2], 0, 1));
        }
    }

    @Test
    void testResetThrowsExceptionWhenUnderlyingDoesNotSupport() throws IOException {
        // test wrapping an underlying stream which does NOT support marking
        try (MarkShieldInputStream msis = new MarkShieldInputStream(new NullInputStream(64, false, false))) {
            assertThrows(UnsupportedOperationException.class, msis::reset);
        }
    }

    @Test
    void testResetThrowsExceptionWhenUnderlyingSupports() throws IOException {
        // test wrapping an underlying stream which supports marking
        try (MarkShieldInputStream msis = new MarkShieldInputStream(new NullInputStream(64, true, false))) {
            assertThrows(UnsupportedOperationException.class, msis::reset);
        }
    }
}