package eu.dnetlib.validatorapi.routes;

import org.apache.camel.builder.RouteBuilder;
import org.json.JSONObject;
import org.json.XML;
import org.springframework.stereotype.Component;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import java.io.StringReader;
import java.io.StringWriter;
import java.util.ArrayList;
import java.util.List;

@Component
public class OaiSetListRoute extends RouteBuilder {

    @Override
    public void configure() throws Exception {

        from("direct:getResponse")
                .process(exchange -> {
                    String endpoint = exchange.getIn().getHeader("endpoint", String.class);
                    exchange.getIn().setHeader("dynamicEndpoint", endpoint);
                })
                .recipientList(header("dynamicEndpoint"))
                .process(exchange -> {
                    List<String> ListSetsXml = exchange.getIn().getBody(ArrayList.class);
                    List<String> desiredJsonParts = new ArrayList<>();
                    String xmlSets = "";

                    // Extract the desired <set> elements from each XML string
                    for (String xml : ListSetsXml) {
                        List<String> extractedSets = extractSets(xml);
                        for (String setXml : extractedSets)
                            xmlSets += setXml;
                    }

                    JSONObject jsonObject = XML.toJSONObject(xmlSets);
                    String jsonString = jsonObject.toString();
                    exchange.getIn().setBody(jsonString);
                });
}

         /*from("direct:processSets")
                .process(exchange -> {
                    // Access the individual response from the ArrayList
                    ArrayList<?> responseList = exchange.getIn().getBody(ArrayList.class);
                    InputStream responseStream = new ByteArrayInputStream(responseList.get(0).toString().getBytes());

                    // Set the converted InputStream as the new body
                    exchange.getIn().setBody(responseStream);
                }).log("${body}")
                .split(xpath("//*[local-name()='set']")).log("${body}")
              //  .log("${body}")
                .aggregate(constant(true), new ListSetAggregationStrategy())
                .completionPredicate(exchangeProperty(Exchange.AGGREGATED_SIZE).isEqualTo(header("CamelSplitSize")))
                .to("direct:processAggregatedSets")
         .log("${body}");*/
/*
        from("direct:processAggregatedSets")
                .process(exchange -> {
                    String aggregatedXml = exchange.getIn().getBody(ArrayList.class) + "";
                    JSONObject jsonObject = XML.toJSONObject(aggregatedXml);
                    String jsonString = jsonObject.toString();
                    exchange.getIn().setBody(jsonString);
                }).to("seda:result");*/
    //}

    private List<String> extractSets(String xml) {
        List<String> setXmls = new ArrayList<>();
        try {
            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
            DocumentBuilder builder = factory.newDocumentBuilder();
            InputSource inputSource = new InputSource(new StringReader(xml));
            Document document = builder.parse(inputSource);

            NodeList setElements = document.getElementsByTagName("set");
            for (int i = 0; i < setElements.getLength(); i++) {
                Node setElement = setElements.item(i);
                String setXml = nodeToString(setElement);
                setXmls.add(setXml);
            }
        } catch (Exception e) {
            // Handle any exceptions that occur during XML parsing or processing
            log.error(e.getMessage());
        }

        return setXmls;
    }

    private String nodeToString(Node node) throws TransformerException {
        StringWriter sw = new StringWriter();
        TransformerFactory tf = TransformerFactory.newInstance();
        Transformer transformer = tf.newTransformer();
        transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
        transformer.transform(new DOMSource(node), new StreamResult(sw));
        return sw.toString();
    }
}