import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;

import java.io.*;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;


public class DOMViewer {
    public static void main(String[] args) throws Exception {
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        DocumentBuilder builder = factory.newDocumentBuilder();

        if (args.length > 0) {
            new GDom(builder, args[0]);
        } else {
            new TDom(builder);
        }
    }

    static Node load(String filename, DocumentBuilder builder) {
        Node dom = null;

        try {
            new FileReader(filename);
        } catch (java.io.IOException ioe) {
            System.out.println("--- Error --- Couldn't find/open file: " +
                filename);
        }

        try {
            dom = builder.parse(new File(filename).toURL().toString());
        } catch (Exception pe) {
            System.out.println("--- Error --- Failed parsing file: " +
                filename);
        }

        return dom;
    }

    static String toString(Node dom) {
        return toString(dom.getFirstChild(), "");
    }

    static String toString(Node node, String indent) {
        String s = "";

        if (node != null) {
            switch (node.getNodeType()) {
            case Node.TEXT_NODE:

                String txt = node.getNodeValue().trim();

                if (!txt.equals("")) {
                    s += (indent + txt + "\n");
                }

                break;

            case Node.COMMENT_NODE:
                s += (indent + "<!--" + node.getNodeValue().trim() + "-->\n");

                break;

            case Node.CDATA_SECTION_NODE:
                s += (indent + "<![CDATA[" + node.getNodeValue().trim() +
                "]]>\n");

                break;

            case Node.PROCESSING_INSTRUCTION_NODE:
                s += (indent + "<?" + node.getNodeName() + " " +
                node.getNodeValue() + "?>\n");

                break;

            case Node.ELEMENT_NODE:
                s += (indent + "<" + node.getNodeName());

                if (node.hasAttributes()) {
                    NamedNodeMap attributes = node.getAttributes();

                    for (int i = 0; i < attributes.getLength(); i++) {
                        Node attr = attributes.item(i);
                        s += (" " + attr.getNodeName() + "=\"" +
                        attr.getNodeValue() + "\"");
                    }
                }

                s += ">\n";
                s += toString(node.getFirstChild(), indent + "  ");
                s += (indent + "</" + node.getNodeName() + ">\n");

                break;

            default:

                String v = node.getNodeValue();

                if (v != null) {
                    v = v.trim();
                }

                System.out.println("Type not suppoerted: " +
                    typeName(node.getNodeType()) + "       name=\"" +
                    node.getNodeName() + "\"  value=\"" + v + "\"");
                s += toString(node.getFirstChild(), indent + "  ");
            }

            s += toString(node.getNextSibling(), indent);
        }

        return s;
    }

    static String typeName(int typeNum) {
        switch (typeNum) {
        case Node.CDATA_SECTION_NODE:
            return "CDATA_SECTION_NODE";

        case Node.COMMENT_NODE:
            return "COMMENT_NODE";

        case Node.ELEMENT_NODE:
            return "ELEMENT_NODE";

        case Node.PROCESSING_INSTRUCTION_NODE:
            return "PROCESSING_INSTRUCTION_NODE";

        case Node.TEXT_NODE:
            return "TEXT_NODE";

        default:
            return "not considered";
        }
    }

    static Node move(Node node, Node nd) {
        if (nd != null) {
            switch (node.getNodeType()) {
            case Node.ELEMENT_NODE:

                Element e = (Element) node;

                if (e.hasAttribute("cursor")) {
                    e.removeAttribute("cursor");
                }

                break;

            case Node.TEXT_NODE:
            case Node.COMMENT_NODE:
            case Node.PROCESSING_INSTRUCTION_NODE:
            case Node.CDATA_SECTION_NODE:
                node.setNodeValue(node.getNodeValue().replaceAll(" =========================",
                        ""));

                break;

            default:}

            node = nd;

            switch (node.getNodeType()) {
            case Node.ELEMENT_NODE:
                ((Element) node).setAttribute("cursor",
                    " =========================");

                break;

            case Node.TEXT_NODE:
            case Node.COMMENT_NODE:
            case Node.PROCESSING_INSTRUCTION_NODE:
            case Node.CDATA_SECTION_NODE:
                node.setNodeValue(node.getNodeValue() +
                    " =========================");

                break;

            default:}
        }

        return node;
    }
}


class TDom {
    Node dom = null;
    Node curNode;

    TDom(DocumentBuilder builder) {
        boolean quit = false;

        while (!quit) {
            System.out.print("Please type a request (h for help): ");

            int request = 'h';

            try {
                request = System.in.read();
            } catch (java.io.IOException ioe) {
                System.out.print("\n--- Error --- Couldn't read request");
            }

            System.out.println();

            switch (request) {
            case 'q':
                quit = true;

                break;

            case 'h':
                System.out.print("Available options\n" + "     q: quit\n" +
                    "     h: help\n" + "     n: load a new xml file\n" +
                    "     p: print xml file\n" + "     d: move cursor down\n" +
                    "     u: move cursor up\n" + "     l: move cursor left\n" +
                    "     r: move cursor right\n");

                break;

            case 'n':
                System.out.print("Please type a filename: ");

                String filename = "";
                char ch = ' ';

                try {
                    while (ch <= ' ') {
                        ch = (char) System.in.read();
                    }

                    while (ch > ' ') {
                        filename += ch;
                        ch = (char) System.in.read();
                    }
                } catch (java.io.IOException ioe) {
                    System.out.println("--- Error --- Couldn't read filename");
                }

                curNode = dom = DOMViewer.load(filename, builder);

                break;

            case 'p':

                String s = "";
                s = (dom == null) ? "" : DOMViewer.toString(dom);

                System.out.println(s);

                break;

            case 'd':
                curNode = DOMViewer.move(curNode, curNode.getFirstChild());

                break;

            case 'u':
                curNode = DOMViewer.move(curNode, curNode.getParentNode());

                break;

            case 'l':
                curNode = DOMViewer.move(curNode, curNode.getPreviousSibling());

                break;

            case 'r':
                curNode = DOMViewer.move(curNode, curNode.getNextSibling());

                break;

            default:
                ;
            }
        }
    }
}