/***** BEGIN LICENSE BLOCK *****
 * Version: EPL 1.0/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Eclipse Public
 * License Version 1.0 (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.eclipse.org/legal/epl-v10.html
 *
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * Copyright (C) 2010 Charles O Nutter <headius@headius.com>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
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package org.jruby.ext.psych;

import java.io.InputStream;
import java.io.IOException;
import java.util.Properties;

import org.jcodings.Encoding;
import org.jcodings.specific.UTF16BEEncoding;
import org.jcodings.specific.UTF16LEEncoding;
import org.jcodings.specific.UTF8Encoding;
import org.jruby.Ruby;
import org.jruby.RubyArray;
import org.jruby.RubyModule;
import org.jruby.RubyString;
import org.jruby.internal.runtime.methods.JavaMethod.JavaMethodZero;
import org.jruby.runtime.ThreadContext;
import org.jruby.runtime.Visibility;
import org.jruby.runtime.builtin.IRubyObject;
import org.jruby.runtime.load.Library;
import org.yaml.snakeyaml.error.Mark;

public class PsychLibrary implements Library {
    private static final String DUMMY_VERSION = "0.0";

    public void load(final Ruby runtime, boolean wrap) {
        RubyModule psych = runtime.defineModule("Psych");

        // load version from properties packed with the jar
        Properties props = new Properties();
        try( InputStream is = runtime.getJRubyClassLoader().getResourceAsStream("META-INF/maven/org.yaml/snakeyaml/pom.properties") ) {
            props.load(is);
        }
        catch( IOException e ) {
            // ignored
        }
        String snakeyamlVersion = props.getProperty("version", DUMMY_VERSION);

        if (snakeyamlVersion.endsWith("-SNAPSHOT")) {
            snakeyamlVersion = snakeyamlVersion.substring(0, snakeyamlVersion.length() - "-SNAPSHOT".length());
        }

        // Try to determine if we have a new enough SnakeYAML.
        // Versions before 1.21 removed a Mark constructor that JRuby uses.
        // See https://github.com/bundler/bundler/issues/6878
        if (snakeyamlVersion.equals(DUMMY_VERSION)) {
            try {
                // Use reflection to try to confirm we have a new enough version
                Mark.class.getConstructor(String.class, int.class, int.class, int.class, int[].class, int.class);
            } catch (NoSuchMethodException nsme) {
                throw runtime.newLoadError("bad SnakeYAML version, required 1.21 or higher; check your CLASSPATH for a conflicting jar");
            }
        } else {
            // Parse version string to check for 1.21+
            String[] majorMinor = snakeyamlVersion.split("\\.");

            if (majorMinor.length < 2 || Integer.parseInt(majorMinor[0]) < 1 || Integer.parseInt(majorMinor[1]) < 21) {
                throw runtime.newLoadError(
                        "bad SnakeYAML version " + snakeyamlVersion +
                                ", required 1.21 or higher; check your CLASSPATH for a conflicting jar");
            }
        }

        RubyString version = runtime.newString(snakeyamlVersion + ".0");
        version.setFrozen(true);
        psych.setConstant("SNAKEYAML_VERSION", version);

        String[] versionParts = version.toString().split("\\.");
        final RubyArray versionElements = runtime.newArray(runtime.newFixnum(Integer.parseInt(versionParts[0])), runtime.newFixnum(Integer.parseInt(versionParts[1])), runtime.newFixnum(Integer.parseInt(versionParts[2])));
        versionElements.setFrozen(true);

        psych.getSingletonClass().addMethod("libyaml_version", new JavaMethodZero(psych, Visibility.PUBLIC) {
            @Override
            public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule clazz, String name) {
                return versionElements;
            }
        });
        
        PsychParser.initPsychParser(runtime, psych);
        PsychEmitter.initPsychEmitter(runtime, psych);
        PsychToRuby.initPsychToRuby(runtime, psych);
        PsychYamlTree.initPsychYamlTree(runtime, psych);
    }

    public enum YAMLEncoding {
        YAML_ANY_ENCODING(UTF8Encoding.INSTANCE),
        YAML_UTF8_ENCODING(UTF8Encoding.INSTANCE),
        YAML_UTF16LE_ENCODING(UTF16LEEncoding.INSTANCE),
        YAML_UTF16BE_ENCODING(UTF16BEEncoding.INSTANCE);

        YAMLEncoding(Encoding encoding) {
            this.encoding = encoding;
        }

        public final Encoding encoding;
    }
}