/*
 * Copyright (c) 2012, 2018, 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
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 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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package com.oracle.truffle.sl.launcher;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintStream;
import java.util.HashMap;
import java.util.Map;

import org.graalvm.polyglot.Context;
import org.graalvm.polyglot.PolyglotException;
import org.graalvm.polyglot.Source;
import org.graalvm.polyglot.Value;

public final class SLMain {

    private static final String SL = "sl";

    
The main entry point.
/**
     * The main entry point.
     */
    public static void main(String[] args) throws IOException {
        Source source;
        Map<String, String> options = new HashMap<>();
        String file = null;
        for (String arg : args) {
            if (parseOption(options, arg)) {
                continue;
            } else {
                if (file == null) {
                    file = arg;
                }
            }
        }

        if (file == null) {
            // @formatter:off
            source = Source.newBuilder(SL, new InputStreamReader(System.in), "<stdin>").build();
            // @formatter:on
        } else {
            source = Source.newBuilder(SL, new File(file)).build();
        }

        System.exit(executeSource(source, System.in, System.out, options));
    }

    private static int executeSource(Source source, InputStream in, PrintStream out, Map<String, String> options) {
        Context context;
        PrintStream err = System.err;
        try {
            context = Context.newBuilder(SL).in(in).out(out).options(options).build();
        } catch (IllegalArgumentException e) {
            err.println(e.getMessage());
            return 1;
        }
        out.println("== running on " + context.getEngine());

        try {
            Value result = context.eval(source);
            if (context.getBindings(SL).getMember("main") == null) {
                err.println("No function main() defined in SL source file.");
                return 1;
            }
            if (!result.isNull()) {
                out.println(result.toString());
            }
            return 0;
        } catch (PolyglotException ex) {
            if (ex.isInternalError()) {
                // for internal errors we print the full stack trace
                ex.printStackTrace();
            } else {
                err.println(ex.getMessage());
            }
            return 1;
        } finally {
            context.close();
        }
    }

    private static boolean parseOption(Map<String, String> options, String arg) {
        if (arg.length() <= 2 || !arg.startsWith("--")) {
            return false;
        }
        int eqIdx = arg.indexOf('=');
        String key;
        String value;
        if (eqIdx < 0) {
            key = arg.substring(2);
            value = null;
        } else {
            key = arg.substring(2, eqIdx);
            value = arg.substring(eqIdx + 1);
        }

        if (value == null) {
            value = "true";
        }
        int index = key.indexOf('.');
        String group = key;
        if (index >= 0) {
            group = group.substring(0, index);
        }
        options.put(key, value);
        return true;
    }

}