/*
 *  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
 *
 *    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.
 */
package org.codehaus.groovy.control.io;

import org.codehaus.groovy.control.CompilerConfiguration;

import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.net.URI;

/**
 * A ReaderSource for source strings.
 */
public class InputStreamReaderSource extends AbstractReaderSource {
    private InputStream stream;  // The InputStream from which we produce a Reader.

    /**
     * Creates the ReaderSource from a File descriptor.
     *
     * @param stream        stream containing source
     * @param configuration configuration for compiling source
     */
    public InputStreamReaderSource(InputStream stream, CompilerConfiguration configuration) {
        super(configuration);
        this.stream = stream;
    }

    /**
     * Returns a new Reader on the underlying source object.
     */
    @Override
    public Reader getReader() throws IOException {
        if (stream != null) {
            Reader reader = new InputStreamReader(stream, configuration.getSourceEncoding());
            stream = null;
            return reader;
        }
        return null;
    }

    /**
     * Returns true if the source can be restarted (ie. if getReader()
     * will return non-null on subsequent calls).
     */
    @Override
    public boolean canReopenSource() {
        return false;
    }

    /**
     * TODO: Should return the URI for this source, but we can't know what it is here.
     *
     * @return null
     */
    @Override
    public URI getURI() {
        return null;
    }
}
