package com.github.dtschust.zork.parser;

import com.github.dtschust.zork.objects.ZorkContainer;
import com.github.dtschust.zork.objects.ZorkCreature;
import com.github.dtschust.zork.objects.ZorkItem;
import com.github.dtschust.zork.objects.ZorkRoom;
import com.github.dtschust.zork.parser.dom.DOMElement;
import org.w3c.dom.Element;

import javax.xml.parsers.DocumentBuilderFactory;
import java.io.File;
import java.nio.channels.NonReadableChannelException;

public class ZorkXMLParser extends ZorkParser {
    public ZorkXMLParser(final PropertyParseStrategy<ZorkCreature> creatureStrategy,
                         final PropertyParseStrategy<ZorkContainer> containerStrategy,
                         final PropertyParseStrategy<ZorkItem> itemStrategy,
                         final PropertyParseStrategy<ZorkRoom> roomStrategy) {
        super(creatureStrategy, containerStrategy, itemStrategy, roomStrategy);
    }

    @Override
    protected Property getRootProperty(String filename) {
        File file = new File(filename);
        if (!file.canRead()) {
            System.out.println("Error opening file.  Exiting...");
            throw new NonReadableChannelException();
        }

        try {
            // Open the xml file
            final DocumentBuilderFactory builder = DocumentBuilderFactory.newInstance();
            // Limit XML features to mitigate vulnerabilities
            builder.setFeature("http://apache.org/xml/features/disallow-doctype-decl", true);
            builder.setFeature("http://xml.org/sax/features/external-general-entities", false);
            builder.setFeature("http://xml.org/sax/features/external-parameter-entities", false);

            final Element rootElement = builder.newDocumentBuilder().parse(file).getDocumentElement();
            return DOMElement.of(rootElement);
        } catch (final Exception ignored) {
            System.out.println("Invalid XML file, exiting");
            System.exit(-1);
            return null; // never reached
        }
    }
}