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/*
 * Copyright (c) 2019, 2020, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * The Universal Permissive License (UPL), Version 1.0
 *
 * Subject to the condition set forth below, permission is hereby granted to any
 * person obtaining a copy of this software, associated documentation and/or
 * data (collectively the "Software"), free of charge and under any and all
 * copyright rights in the Software, and any and all patent rights owned or
 * freely licensable by each licensor hereunder covering either (i) the
 * unmodified Software as contributed to or provided by such licensor, or (ii)
 * the Larger Works (as defined below), to deal in both
 *
 * (a) the Software, and
 *
 * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
 * one is included with the Software each a "Larger Work" to which the Software
 * is contributed by such licensors),
 *
 * without restriction, including without limitation the rights to copy, create
 * derivative works of, display, perform, and distribute the Software and make,
 * use, sell, offer for sale, import, export, have made, and have sold the
 * Software and the Larger Work(s), and to sublicense the foregoing rights on
 * either these or other terms.
 *
 * This license is subject to the following condition:
 *
 * The above copyright notice and either this complete permission notice or at a
 * minimum a reference to the UPL must be included in all copies or substantial
 * portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
package com.oracle.truffle.js.shell;

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

import org.graalvm.shadowed.org.jline.reader.EndOfFileException;
import org.graalvm.shadowed.org.jline.reader.History;
import org.graalvm.shadowed.org.jline.reader.LineReader;
import org.graalvm.shadowed.org.jline.reader.LineReaderBuilder;
import org.graalvm.shadowed.org.jline.reader.UserInterruptException;
import org.graalvm.shadowed.org.jline.reader.impl.history.DefaultHistory;
import org.graalvm.shadowed.org.jline.terminal.Terminal;
import org.graalvm.shadowed.org.jline.terminal.TerminalBuilder;

public class JLineConsoleHandler implements ConsoleHandler {

    private final Terminal terminal;
    private final LineReader reader;
    private final History history;
    private final String prompt;

    public JLineConsoleHandler(InputStream inStream, OutputStream outStream, String prompt) throws IOException {
        this.terminal = TerminalBuilder.builder().jna(false).streams(inStream, outStream).system(true).build();
        this.history = new DefaultHistory();
        this.prompt = prompt;

        LineReaderBuilder builder = LineReaderBuilder.builder().terminal(terminal).history(history);
        builder.option(LineReader.Option.DISABLE_EVENT_EXPANSION, true);
        builder.variable(LineReader.COMMENT_BEGIN, "//");
        builder.variable(LineReader.BELL_STYLE, "off");
        this.reader = builder.build();
    }

    @Override
    public String readLine() throws IOException {
        try {
            return reader.readLine(prompt);
        } catch (EndOfFileException e) {
            return null;
        } catch (UserInterruptException e) {
            return null;
        }
    }

}