/*****************************************************************************
/* Dieses Servlet liest die Maildaten aus der Datenbank und wandelt sie in ein 
/* XML-Dokument um. Dann wird mit Hilfe einer XSLT Datei die Mail als HTML-Seite 
/* dargestellt.
/*
******************************************************************************/

import org.apache.xerces.parsers.DOMParser;
import org.xml.sax.*;
import org.w3c.dom.*;
import javax.xml.transform.*;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.*;
import javax.xml.parsers.*;
import org.apache.xalan.xsltc.trax.*;
import java.sql.*;
import java.net.*;
import java.text.*;
import javax.mail.internet.*;
import java.util.regex.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import net.dehaen.beans.*;

public class ReadMailServlet extends HttpServlet {
     
    private ServletConfig config;
    ServletContext context;
    HttpSession session;
    UtilBean uBean;
    SimpleDateFormat myformatter = new SimpleDateFormat("dd.MM.yyyy 'um' HH:mm");
    String from_name="";
    String from_address="";
    String attach_dir = "";
    String inhalt = "";
    String subject = "";
    String an, bcc,cc,ordner,erstellt, erhalten,isHtml,msg_id;
    Hashtable fields;
    boolean isFullView;
    boolean showHtml, hasHtml;
    Document document = null;
    PrintWriter out;
    HttpServletRequest request;
    long start;
        
            
    public void init (ServletConfig config)throws ServletException {
        this.config = config;
    }
    
    public void destroy() {} // do nothing
    
    public ServletConfig getServletConfig() {
        return config;
    }
    
    public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        response.setContentType("text/html; charset=ISO-8859-1");
        start = System.currentTimeMillis();
        out = response.getWriter();
        this.request = request;
        this.session = request.getSession(true);
        this.context = getServletContext();
        RequestDispatcher dispatcher = context.getRequestDispatcher("/reload.htm");
        if(session.getAttribute("uBean")==null || session.getAttribute("status")==null){
            dispatcher.forward(request, response);
        }
        this.uBean = (UtilBean)session.getAttribute("uBean");
        if(uBean==null || uBean.getUserId()==null){
            dispatcher.forward(request, response);
        }
        readMail();
    }
      
    private void readMail(){
        fields = new Hashtable();   
        boolean isHtmlView;
        if(request.getParameter("view")!=null && request.getParameter("view").equals("full")){
            isFullView = true;
            fields.put("view","full");
        }
        else {
            isFullView = false;
        }
        
        if(request.getParameter("showHtml")!=null && request.getParameter("showHtml").equals("true")){
            showHtml = true;
            fields.put("showHtml","true");
        }
        else showHtml = false;
        String userId = uBean.getUserId();
        ResultSet rs;
        Connection conn = null;
        URLDecoder decoder = new URLDecoder();
        InternetAddress from;
        if(request.getParameter("msg_id")!=null){
            try{
                conn = uBean.getConnection();
                Statement stmnt = conn.createStatement();
                msg_id = request.getParameter("msg_id");
                fields.put("msgId",msg_id);
                String sql="SELECT * from messages WHERE id = '" + msg_id + "' AND user_id = '"  + userId + "'";
                rs = stmnt.executeQuery(sql);   
                if(rs.next()){
                    String s = "UPDATE messages SET gelesen = 1 WHERE id = '" + msg_id + "' AND user_id = '"  + userId + "'";
                    stmnt.executeUpdate(s);
                    
                    if(rs.getString("an")!=null){
                        fields.put("an",rs.getString("an"));
                    }
                    
                    if(rs.getString("subject")!=null){
                        fields.put("subject",rs.getString("subject"));
                    }
                    
                    try{
                        InternetAddress ad = new InternetAddress(rs.getString("von"));
                        if(ad.getPersonal()!=null){
                            fields.put("from_name",ad.getPersonal());
                        }
                        if(ad.getAddress()!=null){
                            fields.put("from_address", ad.getAddress());
                        }
                    }
                    catch (AddressException e){
                        fields.put("from_address","unbekannt");
                    }
                    fields.put("ordner",rs.getString("ordner"));
                    fields.put("attachments",rs.getString("attachments"));
                    fields.put("attachment_sizes",rs.getString("attachment_size"));
                    fields.put("attach_dir",rs.getString("attach_dir"));
            
                    if(!rs.getString("erstellt").equals("unbekannt")){
                        erstellt = myformatter.format(rs.getTimestamp("erstellt"));
                    }
                    else erstellt = "unbekannt";
                    fields.put("erstellt",erstellt);
                    fields.put("erhalten",myformatter.format(rs.getTimestamp("erhalten")));
                            
                    
                    if(rs.getString("BCC")!=null && !rs.getString("BCC").equals("")){
                        fields.put("bcc",rs.getString("BCC"));
                    }
                    if(rs.getString("CC")!=null && !rs.getString("CC").equals("")){
                        fields.put("cc",rs.getString("CC"));
                    }
                    
                    if(rs.getString("html")==null || rs.getString("html").equals("")){
                        hasHtml=false;
                    }
                    else {
                        hasHtml=true;
                        fields.put("hasHtml","yes");
                    }
                    String view;
                    if(isFullView)view="?view=full";
                    else view="";
                    if(!showHtml){
                        if(hasHtml && (rs.getString("text")==null || rs.getString("text").equals(""))){
                            inhalt = "Dies Mail ist nur im Html-Format lesbar. Klicken Sie <a href='ReadMail?showHtml=true&msg_id=" + msg_id + view + "' ><u>hier</u></a> um sie anzuzeigen.";
                        }
                        else {
                            String text = rs.getString("text");
                            inhalt = text;
                            inhalt = cleanText(text);
                        }//Ende if text==""
                    }//Ende if isHtmlView
                    else {
                        inhalt = rs.getString("html").replaceAll("(?si)<script.*?</script>","");
                        if(inhalt.indexOf("<BODY")>-1){
                            inhalt = inhalt.substring(inhalt.indexOf("<BODY")+6);
                        }
                        if(inhalt.indexOf("</BODY")>-1){
                            inhalt = inhalt.substring(0,inhalt.indexOf("</BODY"));
                        }
            
                        if(inhalt.indexOf("<body")>-1){
                            inhalt = inhalt.substring(inhalt.indexOf("<body")+6);
                        }
                        if(inhalt.indexOf("</body")>-1){
                            inhalt = inhalt.substring(0,inhalt.indexOf("</body"));
                        }
                        inhalt = inhalt.substring(inhalt.indexOf(">")+1);
                        inhalt = inhalt.substring(0,inhalt.lastIndexOf(">"));
            
                    }
                    fields.put("inhalt",inhalt);
                    
                }
                else {
                    fields.put("error","Keine Mail mit dieser ID in der Datenbank!");
                }
                if(conn!=null && !conn.isClosed())conn.close();
            }
            catch (SQLException e){
                fields.put("error",e.getMessage());
            }
                
            catch (NullPointerException e){
                fields.put("error",e.getMessage());
            }
            
            finally {
                try{
                    if(conn!=null && !conn.isClosed())conn.close();
                }
                catch (SQLException e){
                    fields.put("error",e.getMessage());
                }
            }
        }    
        long temp = System.currentTimeMillis() - start;
                session.setAttribute("ReadMailServlet-before createDoc"," " + temp);
                temp = System.currentTimeMillis();
                
            createDocument();
            
                temp = System.currentTimeMillis() - temp;
                session.setAttribute("ReadMailServlet-createDoc-Dauer", " " + temp);
                temp = System.currentTimeMillis();
                
            transformDocument("readMail.xsl");   
                
                temp = System.currentTimeMillis() - temp;
                session.setAttribute("ReadMailServlet-transform-Dauer", " " + temp);
                temp = System.currentTimeMillis() - start;
                session.setAttribute("ReadMailServlet-Dauer", " " + temp);
            //transformDocument(null);
    }
    
    public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {
        doGet(request,  response);
    }
    
    private String cleanText (String text){
        String inhalt;
        if(text!=null){
            try{    
                inhalt = text.replaceAll("<","&lt;");
                inhalt = inhalt.replaceAll(">","&gt;");
                ////RegExp-Sonderzeichen ersetzen//////////////////////
                inhalt = inhalt.replaceAll("\\]","&#93;");
                inhalt = inhalt.replaceAll("\\[","&#91;");
                inhalt = inhalt.replaceAll("\\(","&#40;");
                inhalt = inhalt.replaceAll("\\)"," &#41;");
                inhalt = inhalt.replaceAll("\\*","&#42;");
                inhalt = inhalt.replaceAll("\\?","&#63;");
                inhalt = inhalt.replaceAll("\\\\","&#92;");
                inhalt = inhalt.replaceAll("\\{","&#123;");
                inhalt = inhalt.replaceAll("\\}","&#125;");
                inhalt = inhalt.replaceAll("\\|","&#124;");
                inhalt = inhalt.replaceAll("\\$","&#36;");
                inhalt = inhalt.replaceAll("\\^","&#94;");
                ///////////////////////Zeilenumbrüche einfügen////////////////////////////
                Matcher m;
                Pattern p;
                String temp,r1,r2;
                StringBuffer sb = new StringBuffer();
                try{
                    p = Pattern.compile(".{80}\\S*"); //wenn eine Zeile länger als 80 Zeichen ist,      
                    m = p.matcher(inhalt);
                    r1 = "";
                    int ind = 0;
                    int c = 0; //pro Ersetzung muss der Index um eins versetzt werden
                    while(m.find()){
                        r1 = m.group();
                        ind = m.end()+c;
                        if(r1.length()>110 && r1.lastIndexOf(" ")>0){
                            int ws = r1.length() - r1.lastIndexOf(" "); //wenn das letzte Wort zu lang ist, 
                            if(ws > 0)ind-= ws;                             //wird vorher ein Leeraum gesucht
                        }
                        String temp1 = inhalt.substring(0,ind); //der String bis zum Leerraum
                        String temp2 = inhalt.substring(ind); //der String ab dem Leerraum
                        while(temp2.charAt(0)==' '){
                            temp2=temp2.substring(1);
                            c--;
                        }
                        inhalt = temp1 + "\n" + temp2;
                        c++;
    
                    }
                }
                catch(PatternSyntaxException e){inhalt = text;}
                catch(IndexOutOfBoundsException e){inhalt = text;}
                
                ///////////////////////Links als Link schreiben///////////////////////
                p = Pattern.compile("(http||https||ftp)://\\S*");       
                m = p.matcher(inhalt);
                
                while(m.find()){
                    r1 = m.group();
                    //r2 = r1.replaceAll("/","&#47;");
                    temp = "<a href='" + r1 + "' target='_blank' class='link_blau'>" + r1 + "</a>";
                    m.appendReplacement(sb, temp);
                }
                m.appendTail(sb);
                if(sb.length()>0)inhalt = sb.toString();
                sb.delete(0,sb.length());
                ///////////e-mail-Adressen/////////////////////////////////////
                p = Pattern.compile("[0-9a-zA-Z\\.\\-_]*@[0-9A-Za-z\\.\\-_]*");     
                m = p.matcher(inhalt);
                temp="";
                r1 = "";
                r2 = "";
                
                while(m.find()){
                    r1 = m.group();
                    temp = "<a href='mailto:" + r1 + "' class='link_blau'>" + r1 + "</a>";
                    m.appendReplacement(sb, temp);
                }
                m.appendTail(sb);
                if(sb.length()>0)inhalt = sb.toString();
            }
            catch(PatternSyntaxException e){
                inhalt = text;
            }
            catch(IndexOutOfBoundsException e){
                inhalt = text;
            }
            return inhalt;
        } //Ende if text!=null
        return "";
    }
    
    private void createDocument(){ 

        try{
            DocumentBuilder builder  = DocumentBuilderFactory.newInstance().newDocumentBuilder();
            document = builder.newDocument();
            
            Element root = (Element) document.createElement("mail");
            document.appendChild(root);
            
            String[] mailAtt ={"msgId","hasHtml","view","showHtml"};
            //if(fields.contains(mailAtt[0]))
            String tempStr = mailAtt[0];
            //if(fields.contains(tempStr))root.setAttribute(tempStr,(String)fields.get(tempStr));
            for(int i=0;i<mailAtt.length;i++){
                String s = mailAtt[i];
                if(fields.containsKey(s)){
                    root.setAttribute(s,(String)fields.get(s)); 
                }
            }
            
            
            String[] mailElements =  {"from_address","an","erstellt","erhalten","subject","inhalt","cc","bcc","error"};
            
            for(int i=0;i<mailElements.length;i++){
                String s = mailElements[i];
                if(fields.containsKey(s)){
                    Element tempEl = (Element) document.createElement(s);
                    root.appendChild(tempEl);
                    tempEl.appendChild( document.createTextNode((String)fields.get(s)) );
                }
            }
            
            if(fields.containsKey("attachments")){
                String att_name, att_size;
                String attachments = (String)fields.get("attachments");
                String attachment_sizes = (String)fields.get("attachment_sizes");
                if(!attachments.equals("")){
                    Element attachmentsEl = (Element)document.createElement("attachments");
                    root.appendChild(attachmentsEl);
                    StringTokenizer a_n = new StringTokenizer(attachments,",");
                    StringTokenizer a_s = new StringTokenizer(attachment_sizes,",");
                    while(a_n.hasMoreElements()){
                        att_name = ((String)a_n.nextElement()).trim();
                        att_size = ((String)a_s.nextElement()).trim();
                        Element att=(Element)document.createElement("attachment");
                        attachmentsEl.appendChild(att);
                        att.setAttribute("name",att_name);
                        att.setAttribute("size",att_size);
                        att.setAttribute("dir",(String)fields.get("attach_dir"));

                    }
                }
            }
            
        }
        catch (ParserConfigurationException e){
           session.setAttribute("ParserException",e.getMessage());
        }
    }
    
    private void transformDocument(String xsltFile){
        Transformer transformer;
        try {TransformerFactory transFactory = TransformerFactory.newInstance();     
            if(xsltFile==null || request.getParameter("debug")!=null){
                transformer = transFactory.newTransformer();
            }
            else {
                /* bei aufwändigen stylesheets kann es sich lohnen, dieses nicht immer wieder neu zu parsen
                  ich konnte aber keinen performance-Gewinn feststellen
                if(session.getAttribute("transformer")==null){
                    transformer = transFactory.newTransformer(new StreamSource(context.getRealPath("xslt") + "/" + xsltFile));
                    session.setAttribute("transformer",transformer);
                }
                else {
                    transformer = (Transformer)session.getAttribute("transformer");
                }*/
                transformer = transFactory.newTransformer(new StreamSource(context.getRealPath("xslt") + "/" + xsltFile));
            }
            DOMSource         source = new DOMSource( document ); //das gerade generierte XML-Dokument
            StreamResult      result = new StreamResult(out);
            String  encoding = uBean.getCharSet();
            transformer.setOutputProperty(OutputKeys.ENCODING,encoding);
            transformer.transform(  source, result );
             
         }
         catch( TransformerConfigurationException tce ) {
            out.println("TransformerConfigurationException " + tce.getMessage());
         } 
         catch( TransformerException tfe ) {
            out.println("TransformerException " + tfe.getMessage());
         }
    }
    
}