import java.io.File;

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

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;

class Page {
    public static final String CLASS_NAME = Page.class.getName();

    public static final String ATTRIBUTE_NAME_ID = "id";

    public static final String TAG_NAME_TITLE = "Title";

    public static final String TAG_NAME_FILE = "File";

    private String id = null;

    private String title = null;

    private String file = null;

    // default
    public Page() {
    }

    // field parameters
    public Page(String id, String title, String file) {
        this.id = id;
        this.title = title;
        this.file = file;
    }

    // element
    public Page(Element element) {
        // id
        this.id = element.getAttribute(ATTRIBUTE_NAME_ID);
        // title
        NodeList nodeListTitle = element.getElementsByTagName(TAG_NAME_TITLE);
        for (int i = 0; i < nodeListTitle.getLength(); i++) {
            Element elementTitle = (Element)nodeListTitle.item(i);
            this.title = elementTitle.getFirstChild().getNodeValue();
        }
        // file
        NodeList nodeListFile = element.getElementsByTagName(TAG_NAME_FILE);
        for (int i = 0; i < nodeListFile.getLength(); i++) {
            Element elementFile = (Element)nodeListFile.item(i);
            this.file = elementFile.getFirstChild().getNodeValue();
        }
    }

    // xml file name
    public Page(String xmlName) throws Exception {
        try {
            DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();
            DocumentBuilder documentBuilder = documentBuilderFactory.newDocumentBuilder();
            Document document = documentBuilder.parse(new File(xmlName));
            Element root = document.getDocumentElement();
            // root name check
            if (!CLASS_NAME.equals(root.getTagName())) {
                throw new Exception("root name error.");
            }
            // id
            this.id = root.getAttribute(ATTRIBUTE_NAME_ID);
            // title
            NodeList nodeListTitle = root.getElementsByTagName(TAG_NAME_TITLE);
            for (int i = 0; i < nodeListTitle.getLength(); i++) {
                Element elementTitle = (Element)nodeListTitle.item(i);
                this.title = elementTitle.getFirstChild().getNodeValue();
            }
            // file
            NodeList nodeListFile = root.getElementsByTagName(TAG_NAME_FILE);
            for (int i = 0; i < nodeListFile.getLength(); i++) {
                Element elementFile = (Element)nodeListFile.item(i);
                this.file = elementFile.getFirstChild().getNodeValue();
            }
        } catch (Exception e) {
            throw e;
        }
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public void setFile(String file) {
        this.file = file;
    }

    public String toString() {
        return "[id=" + this.id + ", title=" + this.title + ", file=" + this.file + "]";
    }
}