package de.intevation.gnv.artifacts.fis;

import java.io.IOException;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import javax.xml.xpath.XPathConstants;

import org.apache.log4j.Logger;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

import de.intevation.artifactdatabase.DefaultArtifact;
import de.intevation.artifactdatabase.ProxyArtifact;
import de.intevation.artifactdatabase.XMLUtils;
import de.intevation.artifacts.Artifact;
import de.intevation.artifacts.ArtifactFactory;
import de.intevation.artifacts.ArtifactNamespaceContext;
import de.intevation.artifacts.CallContext;
import de.intevation.artifacts.CallMeta;
import de.intevation.gnv.artifacts.GNVArtifactBase;
import de.intevation.gnv.artifacts.context.GNVArtifactContext;
import de.intevation.gnv.artifacts.fis.product.DefaultProduct;
import de.intevation.gnv.artifacts.fis.product.Product;
import de.intevation.gnv.artifacts.ressource.RessourceFactory;
import de.intevation.gnv.state.DefaultInputData;
import de.intevation.gnv.state.InputData;
import de.intevation.gnv.utils.ArtifactFactoryUtilities;


/**
 * @author Ingo Weinzierl <ingo.weinzierl@intevation.de>
 */
public class FISSelectArtifact extends DefaultArtifact {

    public static final String XPATH_IDENTIFIER_REPLACE = "IDENTIFIER";

    public static final String XPATH_ARTIFACT_CONFIGURATION =
        "/artifact-database/artifacts/artifact[@name='"
        + XPATH_IDENTIFIER_REPLACE + "']";

    public static final String XPATH_UUID = "art:action/art:uuid/@value";

    public static final String XPATH_HASH = "art:action/art:hash/@value";

    public static final String XPATH_INPUT_DATA_VALUE =
        "art:action/art:data/art:input[@name='product']/@value";

    /**
     * this xpath is related to the config.xml document which doesn't have any
     * prefixes yet
     */
    public static final String XPATH_PRODUCTS = "products/product";

    /**
     * this xpath is related to the config.xml document which doesn't have any
     * prefixes yet
     */
    public static final String XPATH_PRODUCT_PARAMETER = "parameters/parameter";

    public static final String XFORM_URL    = "http://www.w3.org/2002/xforms";
    public static final String XFORM_PREFIX = "xform";

    private static Logger log = Logger.getLogger(FISSelectArtifact.class);

    private HashMap  products;
    private Product  current;
    private Artifact artifact;
    private String   name;

    public FISSelectArtifact() {
        super();
    }


    @Override
    public void setup(
        String          identifier,
        ArtifactFactory factory,
        Object          context
    ) {
        log.debug("setup()");
        super.setup(identifier, factory, context);
        this.name = factory.getName();

        if (context instanceof GNVArtifactContext) {
            GNVArtifactContext gnvContext   = (GNVArtifactContext) context;
            Document           doc          = gnvContext.getConfig();
            Node               artifactNode = getConfigurationFragment(doc);

            NodeList products = (NodeList) XMLUtils.xpath(
                artifactNode, XPATH_PRODUCTS, XPathConstants.NODESET);

            if (products != null) {
                this.products = new HashMap(products.getLength());

                for (int i = 0; i < products.getLength(); i++) {
                    Element  productNode    = (Element)products.item(i);
                    String   productName    = productNode.getAttribute("name");
                    NodeList parameterNodes = (NodeList) XMLUtils.xpath(
                        productNode,
                        XPATH_PRODUCT_PARAMETER,
                        XPathConstants.NODESET
                    );

                    Collection<InputData> parameter = null;
                    if (parameterNodes != null) {
                        parameter = new ArrayList(parameterNodes.getLength());

                        for (int j = 0; j < parameterNodes.getLength(); j++) {
                            Element parameterNode = (Element)parameterNodes.item(j);
                            String name  = parameterNode.getAttribute("name");
                            String value = parameterNode.getAttribute("value");
                            parameter.add(new DefaultInputData(name, value));
                        }
                    }
                    Node artifactFactoryNode = (Node) XMLUtils.xpath(
                        productNode, "artifact-factory", XPathConstants.NODE
                    );

                    ArtifactFactory artifactFactory =
                        new ArtifactFactoryUtilities().createArtitfactFactor(
                            doc, artifactFactoryNode
                        );

                    this.products.put(productName, new DefaultProduct(
                        productName, parameter, artifactFactory)
                    );
                }
            }
        }
    }


    @Override
    public Document feed(Document target, CallContext context) {
        log.debug("FISSelectArtifact.feed()");

        if (artifact == null) {
            Document document    = XMLUtils.newDocument();
            String   productName = XMLUtils.xpathString(
                target,
                XPATH_INPUT_DATA_VALUE,
                ArtifactNamespaceContext.INSTANCE
            );

            current = (Product) products.get(productName);

            String reportNode = null;
            String resultNode = null;
            String msg        = null;

            if (current != null) {
                reportNode = "result";
                resultNode = "success";
                msg        = "Feed was successfully. New Artifact created.";
            }
            else {
                reportNode = "exceptionreport";
                resultNode = "exception";
                msg        = "Product does not exist.";
            }

            XMLUtils.ElementCreator creator = new XMLUtils.ElementCreator(
                document,
                ArtifactNamespaceContext.NAMESPACE_URI,
                ArtifactNamespaceContext.NAMESPACE_PREFIX
            );

            Element report  = creator.create(reportNode);
            Element success = creator.create(resultNode);
            success.setTextContent(msg);
            report.appendChild(success);
            document.appendChild(report);

            return document;
        }
        else {
            return artifact.feed(target, context);
        }
    }


    @Override
    public Document advance(Document target, CallContext context) {
        log.debug("FISSelectArtifact.advance()");

        if (artifact != null) {
            Document result = artifact.advance(target, context);
            context.putContextValue(ProxyArtifact.REPLACE_PROXY, artifact);
            return result;
        }

        Document result = XMLUtils.newDocument();
        if (current == null) {
            // artifact needs to be feeded first
            String msg = "Artifact is not configured properly. Call 'feed' fist.";
            log.error(msg);

            XMLUtils.ElementCreator creator = new XMLUtils.ElementCreator(
                result,
                ArtifactNamespaceContext.NAMESPACE_URI,
                ArtifactNamespaceContext.NAMESPACE_PREFIX
            );

            Element report = creator.create("exceptionreport");
            Element exception = creator.create("exception");
            exception.setTextContent(msg);
            report.appendChild(exception);
            result.appendChild(report);

            return result;
        }

        String uuid = XMLUtils.xpathString(
            target, XPATH_UUID, ArtifactNamespaceContext.INSTANCE
        );

        String hash = XMLUtils.xpathString(
            target, XPATH_HASH, ArtifactNamespaceContext.INSTANCE
        );

        artifact = current.getArtifactFactory().createArtifact(
            uuid, context
        );

        Document feedDocument = feedDocument(uuid, hash);
        artifact.feed(feedDocument(uuid, hash), context);

        result = ((GNVArtifactBase) artifact).initialize(context);
        if (artifact instanceof GNVArtifactBase) {
            ((GNVArtifactBase) artifact).setProduct(current);
        }
        context.putContextValue(ProxyArtifact.REPLACE_PROXY, artifact);
        return result;
    }


    @Override
    public Document describe(Document data, CallContext context) {
        log.debug("FISSelectArtifact.describe()");

        // create root node
        Document document               = XMLUtils.newDocument();
        XMLUtils.ElementCreator creator = new XMLUtils.ElementCreator(
            document,
            ArtifactNamespaceContext.NAMESPACE_URI,
            ArtifactNamespaceContext.NAMESPACE_PREFIX
        );

        Element rootNode = creator.create("result");
        Element typeNode = creator.create("type");
        creator.addAttr(typeNode, "name", "describe");
        rootNode.appendChild(typeNode);

        Element uuidNode = creator.create("uuid");
        creator.addAttr(uuidNode, "value", super.identifier);
        rootNode.appendChild(uuidNode);

        Element hashNode = creator.create("hash");
        creator.addAttr(hashNode, "value", hash());
        rootNode.appendChild(hashNode);

        // create output node
        Element out = creator.create("outputs");
        rootNode.appendChild(out);

        // create current state
        Element state = creator.create("state");
        creator.addAttr(state, "name", "choose-product");
        creator.addAttr(state, "description", "Auswahl des Produktes.");
        rootNode.appendChild(state);

        // create reachable states
        Element rStates = creator.create("reachable-states");
        appendProducts(document, rStates, context);
        rootNode.appendChild(rStates);

        // create model
        Element model = creator.create("model");
        Element input = creator.create("input");
        creator.addAttr(input, "name", "product");
        creator.addAttr(input, "type", "String");
        model.appendChild(input);
        rootNode.appendChild(model);

        // create ui
        Element ui      = creator.create("ui");
        Element dynamic = creator.create("dynamic");
        appendSelectProducts(document, dynamic, context.getMeta());
        ui.appendChild(dynamic);
        rootNode.appendChild(ui);

        document.appendChild(rootNode);
        return document;
    }


    @Override
    public void out(Document document, OutputStream out, CallContext context)
    throws IOException
    {
        log.debug("FISSelectArtifact.out()");
        if (artifact != null) {
            artifact.out(document, out, context);
        }
    }


    protected void appendProducts(
        Document document,
        Node     parent,
        Object   context
    ) {
        Iterator iter = products.values().iterator();

        XMLUtils.ElementCreator creator = new XMLUtils.ElementCreator(
            document,
            ArtifactNamespaceContext.NAMESPACE_URI,
            ArtifactNamespaceContext.NAMESPACE_PREFIX
        );

        while(iter.hasNext()) {
            Product prod = (Product) iter.next();
            String  name = prod.getName();

            Element current = creator.create("state");
            creator.addAttr(current, "name", name);
            creator.addAttr(current, "description", name);
            parent.appendChild(current);
        }
    }


    protected void appendSelectProducts(
        Document document,
        Node     node,
        CallMeta callMeta
    ) {
        RessourceFactory ressource = RessourceFactory.getInstance();

        XMLUtils.ElementCreator creator = new XMLUtils.ElementCreator(
            document,
            XFORM_URL,
            XFORM_PREFIX
        );

        String  selectboxName = "product";
        Element selectNode    = creator.create("select1");
        creator.addAttr(selectNode, "ref", selectboxName);

        Element lableNode = creator.create("label");
        lableNode.setTextContent(ressource.getRessource(callMeta.getLanguages(),
                selectboxName,
                selectboxName
            )
        );

        Element choiceNode = creator.create("choices");
        selectNode.appendChild(lableNode);
        selectNode.appendChild(choiceNode);

        Iterator it = products.values().iterator();
        while (it.hasNext()) {
            Product p               = (Product) it.next();
            Element itemNode        = creator.create("item");
            Element choiceLableNode = creator.create("label");
            choiceLableNode.setTextContent(ressource.getRessource(
                callMeta.getLanguages(),
                p.getName(),
                p.getName()
            ));
            itemNode.appendChild(choiceLableNode);

            Element choiceValueNode = creator.create("value");
            choiceValueNode.setTextContent(p.getName());
            itemNode.appendChild(choiceValueNode);
            choiceNode.appendChild(itemNode);
        }

        node.appendChild(selectNode);
    }


    protected Node getConfigurationFragment(Document document) {
        String xpathQuery = XPATH_ARTIFACT_CONFIGURATION.replaceAll(
            XPATH_IDENTIFIER_REPLACE, name
        );

        return (Node) XMLUtils.xpath(document, xpathQuery, XPathConstants.NODE);
    }


    protected Document feedDocument(String uuid, String hash) {
        Document document = XMLUtils.newDocument();

        XMLUtils.ElementCreator creator = new XMLUtils.ElementCreator(
            document,
            ArtifactNamespaceContext.NAMESPACE_URI,
            ArtifactNamespaceContext.NAMESPACE_PREFIX
        );
        Element  rootNode = creator.create("action");

        Element typeNode = creator.create("type");
        creator.addAttr(typeNode, "name", "feed");
        rootNode.appendChild(typeNode);

        Element uuidNode = creator.create("uuid");
        creator.addAttr(uuidNode, "value", uuid);
        rootNode.appendChild(uuidNode);

        Element hashNode = creator.create("hash");
        creator.addAttr(hashNode, "value", hash);
        rootNode.appendChild(hashNode);

        Element dataNode = creator.create("data");
        rootNode.appendChild(dataNode);

        Collection<InputData> parameter = this.current.getParameter();
        if (parameter != null) {
            Iterator<InputData> parameterIt = parameter.iterator();

            while (parameterIt.hasNext()) {
                InputData inputData = parameterIt.next();

                Element inputNode = creator.create("input");
                creator.addAttr(inputNode, "name", inputData.getName());
                creator.addAttr(inputNode, "value", inputData.getValue());
                dataNode.appendChild(inputNode);
            }
        }
        document.appendChild(rootNode);
        return document;
    }
}
// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8: