// wikiCode.java 
// -------------------------------------
// part of YACY
// (C) by Michael Peter Christen; mc@anomic.de
// first published on http://www.anomic.de
// Frankfurt, Germany, 2004
//
// This file ist contributed by Alexander Schier
// last major change: 09.08.2004
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
//
// Using this software in any meaning (reading, learning, copying, compiling,
// running) means that you agree that the Author(s) is (are) not responsible
// for cost, loss of data or any harm that may be caused directly or indirectly
// by usage of this softare or this documentation. The usage of this software
// is on your own risk. The installation and usage (starting/running) of this
// software may allow other people or application to access your computer and
// any attached devices and is highly dependent on the configuration of the
// software which must be done by the user of the software; the author(s) is
// (are) also not responsible for proper configuration and usage of the
// software, even if provoked by documentation provided together with
// the software.
//
// Any changes to this file according to the GPL as documented in the file
// gpl.txt aside this file in the shipment you received can be done to the
// lines that follows this copyright notice here, but changes must not be
// done inside the copyright notive above. A re-distribution must contain
// the intact and unchanged copyright notice.
// Contributions and changes to the program code must be marked as such.

// Contains contributions from Alexander Schier [AS]
// and Marc Nause [MN]

package de.anomic.data;

import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;

import de.anomic.plasma.plasmaSwitchboard;
import de.anomic.server.serverCore;
import de.anomic.yacy.yacyCore;

public class wikiCode {
    private String numListLevel="";
    private String ListLevel="";
    private String defListLevel="";
    private plasmaSwitchboard sb;
    private boolean escape = false;           //needed for escape
    private boolean escaped = false;          //needed for <pre> not getting in the way
    private boolean escapeSpan = false;       //needed for escape symbols [= and =] spanning over several lines 
    private boolean preformatted = false;     //needed for preformatted text
    private boolean preformattedSpan = false; //needed for <pre> and </pre> spanning over several lines
    private int preindented = 0;              //needed for indented <pre>s
    private int escindented = 0;              //needed for indented [=s
        
    public wikiCode(plasmaSwitchboard switchboard){
        sb=switchboard;
    }

    public String transform(String content){
        try {
            return transform(content.getBytes("UTF-8"), sb);
        } catch (UnsupportedEncodingException e) {
            return transform(content.getBytes(), sb);
        }
    }
    public String transform(byte[] content){
        return transform(content, sb);
    }

    public String transform(byte[] content, plasmaSwitchboard switchboard) {
        ByteArrayInputStream bais = new ByteArrayInputStream(content);
        try {
            BufferedReader br = new BufferedReader(new InputStreamReader(bais,
                    "UTF-8"));
            String line;
            StringBuffer out = new StringBuffer(content.length);
            try {
                while ((line = br.readLine()) != null) {
                    out.append(transformLine(line, switchboard)).append(
                            serverCore.crlfString);
                }
                return out.toString();
            } catch (UnsupportedEncodingException e1) {
                // can not happen
                return null;
            }
        } catch (IOException e) {
            return "internal error: " + e.getMessage();
        }
    }
    
    public static String replaceHTML(String result) {
        if (result == null) return null;
        int p0;
	
	// avoide html inside
	// Ampersands have to be replaced first. If they were replaced later,
	// other replaced characters containing ampersands would get messed up.
	p0 = 0; while ((p0 = result.indexOf("&", p0)) >= 0) {result = result.substring(0, p0) + "&amp;" + result.substring(p0 + 1); p0++;}
	p0 = 0; while ((p0 = result.indexOf('"', p0)) >= 0) result = result.substring(0, p0) + "&quot;" + result.substring(p0 + 1);
	p0 = 0; while ((p0 = result.indexOf("<", p0)) >= 0) result = result.substring(0, p0) + "&lt;" + result.substring(p0 + 1);
	p0 = 0; while ((p0 = result.indexOf(">", p0)) >= 0) result = result.substring(0, p0) + "&gt;" + result.substring(p0 + 1);
	//p0 = 0; while ((p0 = result.indexOf("*", p0)) >= 0) result = result.substring(0, p0) + "&#149;" + result.substring(p0 + 1);
	p0 = 0; while ((p0 = result.indexOf("(C)", p0)) >= 0) result = result.substring(0, p0) + "&copy;" + result.substring(p0 + 3);
	
	return result;
    }

    public String transformLine(String result, plasmaSwitchboard switchboard) {
	// transform page
	int p0, p1;
	boolean defList = false;    //needed for definition lists
        
	result = replaceHTML(result);
	
	//check if line contains any escape symbol or tag for preformatted text 
	//or if we are in an esacpe sequence already or if we are in a preforamtted text
	//if that's the case the program will continue further below 
	//(see code for [= and =] and <pre> and </pre>) [MN]
	if((result.indexOf("[=")<0)&&(result.indexOf("=]")<0)&&(!escapeSpan)&&
	   (result.indexOf("&lt;pre&gt;")<0)&&(result.indexOf("&lt;/pre&gt;")<0)&&(!preformattedSpan)){
        
            // format lines
            if (result.startsWith(" ")) result = "<tt>" + result + "</tt>";
            if (result.startsWith("----")) result = "<hr>";
	
	    // citings contributed by [MN]
	    if(result.startsWith(":")){
		    String head = "";
		    String tail = "";
		    while(result.startsWith(":")){
			    head = head + "<blockquote>";
			    tail = tail + "</blockquote>";
			    result = result.substring(1);
		    }
		    result = head + result + tail;
	    }
	    // end contrib [MN]	

            // format headers
            if ((p0 = result.indexOf("====")) >= 0) {
                p1 = result.indexOf("====", p0 + 4);
                if (p1 >= 0) result = result.substring(0, p0) + "<h4>" +
                                      result.substring(p0 + 4, p1) + "</h4>" +
                                      result.substring(p1 + 4);
            }
            if ((p0 = result.indexOf("===")) >= 0) {
                p1 = result.indexOf("===", p0 + 3);
                if (p1 >= 0) result = result.substring(0, p0) + "<h3>" +
                                      result.substring(p0 + 3, p1) + "</h3>" +
                                      result.substring(p1 + 3);
            }
            if ((p0 = result.indexOf("==")) >= 0) {
                p1 = result.indexOf("==", p0 + 2);
                if (p1 >= 0) result = result.substring(0, p0) + "<h2>" +
                                      result.substring(p0 + 2, p1) + "</h2>" +
                                      result.substring(p1 + 2);
            }

            if ((p0 = result.indexOf("'''''")) >= 0) {
                p1 = result.indexOf("'''''", p0 + 5);
                if (p1 >= 0) result = result.substring(0, p0) + "<b><i>" +
                                      result.substring(p0 + 5, p1) + "</i></b>" +
                                      result.substring(p1 + 5);
            }
            if ((p0 = result.indexOf("'''")) >= 0) {
                p1 = result.indexOf("'''", p0 + 3);
                if (p1 >= 0) result = result.substring(0, p0) + "<b>" +
                                      result.substring(p0 + 3, p1) + "</b>" +
                                      result.substring(p1 + 3);
            }
            if ((p0 = result.indexOf("''")) >= 0) {
                p1 = result.indexOf("''", p0 + 2);
                if (p1 >= 0) result = result.substring(0, p0) + "<i>" +
                                      result.substring(p0 + 2, p1) + "</i>" +
                                      result.substring(p1 + 2);
            }
	
	
	    //* unorderd Lists contributed by [AS]
	    //** Sublist
	    if(result.startsWith(ListLevel + "*")){ //more stars
    		    p0 = result.indexOf(ListLevel);
		    p1 = result.length();
		    result = "<ul>" + serverCore.crlfString +
			     "<li>" +
			     result.substring(ListLevel.length() + 1, p1) +
			     "</li>";
		    ListLevel += "*";
	    }else if(ListLevel.length() > 0 && result.startsWith(ListLevel)){ //equal number of stars
		    p0 = result.indexOf(ListLevel);
		    p1 = result.length();
		    result = "<li>" +
			     result.substring(ListLevel.length(), p1) +
			     "</li>";
	    }else if(ListLevel.length() > 0){ //less stars
		    int i = ListLevel.length();
		    String tmp = "";
		
		    while(! result.startsWith(ListLevel.substring(0,i)) ){
			    tmp += "</ul>";
			    i--;
		    }
		    ListLevel = ListLevel.substring(0,i);
		    p0 = ListLevel.length();
		    p1 = result.length();
		
		    if(ListLevel.length() > 0){
			    result = tmp +
				     "<li>" +
				     result.substring(p0, p1) +
				     "</li>";
		    }else{
			result = tmp + result.substring(p0, p1);
		    }
	    }


	    //# sorted Lists contributed by [AS]
	    //## Sublist
	    if(result.startsWith(numListLevel + "#")){ //more #
		    p0 = result.indexOf(numListLevel);
		    p1 = result.length();
		    result = "<ol>" + serverCore.crlfString +
			     "<li>" +
			     result.substring(numListLevel.length() + 1, p1) +
			     "</li>";
		    numListLevel += "#";
	    }else if(numListLevel.length() > 0 && result.startsWith(numListLevel)){ //equal number of #
		    p0 = result.indexOf(numListLevel);
		    p1 = result.length();
		    result = "<li>" +
			     result.substring(numListLevel.length(), p1) +
			     "</li>";
	    }else if(numListLevel.length() > 0){ //less #
		    int i = numListLevel.length();
		    String tmp = "";
		
		    while(! result.startsWith(numListLevel.substring(0,i)) ){
			    tmp += "</ol>";
			    i--;
		    }
		    numListLevel = numListLevel.substring(0,i);
		    p0 = numListLevel.length();
		    p1 = result.length();
		
		    if(numListLevel.length() > 0){
			    result = tmp +
				     "<li>" +
				     result.substring(p0, p1) +
				     "</li>";
		    }else{
			    result = tmp + result.substring(p0, p1);
		    }
	    }
	    // end contrib [AS]
	
	    //* definition Lists contributed by [MN] based on unordered list code by [AS]
	    if(result.startsWith(defListLevel + ";")){ //more semicolons
		    String dt = ""; 
		    String dd = "";
		    p0 = result.indexOf(defListLevel);
		    p1 = result.length();
		    String resultCopy = result.substring(defListLevel.length() + 1, p1);
		    if((p0 = resultCopy.indexOf(":")) > 0){
			    dt = resultCopy.substring(0,p0);
			    dd = resultCopy.substring(p0+1);
			    result = "<dl>" + "<dt>" + dt + "</dt>" + "<dd>" + dd;
			    defList = true;
		    }
		    defListLevel += ";";
	    }else if(defListLevel.length() > 0 && result.startsWith(defListLevel)){ //equal number of semicolons
		    String dt = ""; 
		    String dd = "";
		    p0 = result.indexOf(defListLevel);
		    p1 = result.length();
		    String resultCopy = result.substring(defListLevel.length(), p1);
		    if((p0 = resultCopy.indexOf(":")) > 0){
			    dt = resultCopy.substring(0,p0);
			    dd = resultCopy.substring(p0+1);
			    result = "<dt>" + dt + "</dt>" + "<dd>" + dd;
			    defList = true;
		    }
	    }else if(defListLevel.length() > 0){ //less semicolons
		    String dt = ""; 
		    String dd = "";
		    int i = defListLevel.length();
		    String tmp = "";
		    while(! result.startsWith(defListLevel.substring(0,i)) ){
			    tmp += "</dd></dl>";
			    i--;
		    }
		    defListLevel = defListLevel.substring(0,i);
		    p0 = defListLevel.length();
		    p1 = result.length();
		    if(defListLevel.length() > 0){
			    String resultCopy = result.substring(p0, p1);
			    if((p0 = resultCopy.indexOf(":")) > 0){
				    dt = resultCopy.substring(0,p0);
				    dd = resultCopy.substring(p0+1);
				    result = tmp + "<dt>" + dt + "</dt>" + "<dd>" + dd;
				    defList = true;
			    }
		
		    }else{
			    result = tmp + result.substring(p0, p1);
		    }
	    }
	    // end contrib [MN]	


            // create links
            String kl, kv, alt, align;
            int p;
            // internal links and images
            while ((p0 = result.indexOf("[[")) >= 0) {
                p1 = result.indexOf("]]", p0 + 2);
                if (p1 <= p0) break;
                kl = result.substring(p0 + 2, p1);

                // this is the part of the code that's responsible for images
                // contributed by [MN]
                if (kl.startsWith("Image:")) {
                    alt = "";
                    align = "";
                    kv = "";
                    kl = kl.substring(6);

                    // are there any arguments for the image?
                    if ((p = kl.indexOf("|")) > 0) {
                        kv = kl.substring(p + 1);
                        kl = kl.substring(0, p);

                        // if there are 2 arguments, write them into ALIGN and
                        // ALT
                        if ((p = kv.indexOf("|")) > 0) {
                            align = " align=\"" + kv.substring(0, p) + "\"";
                            alt = " alt=\"" + kv.substring(p + 1) + "\"";
                        }

                        // if there is just one, put it into ALT
                        else
                            alt = " alt=\"" + kv + "\"";
                    }

                    // replace incomplete URLs and make them point to http://peerip:port/...
                    // with this feature you can access an image in DATA/HTDOCS/share/yacy.gif
                    // using the wikicode [[Image:share/yacy.gif]]
                    // or an image DATA/HTDOCS/grafics/kaskelix.jpg with [[Image:grafics/kaskelix.jpg]]
                    // you are free to use other sub-paths of DATA/HTDOCS
                    if (!((kl.indexOf("://"))>=0)) {
                        kl = "http://" + yacyCore.seedDB.mySeed.getAddress().trim() + "/" + kl;
                    }

                    result = result.substring(0, p0) + "<img src=\"" + kl + "\"" + align.trim() + alt.trim() + ">" + result.substring(p1 + 2);
                }
                // end contrib [MN]

                // if it's no image, it might be an internal link
                else {
                    if ((p = kl.indexOf("|")) > 0) {
                        kv = kl.substring(p + 1);
                        kl = kl.substring(0, p);
                    } else {
                        kv = kl;
                    }
                    if (switchboard.wikiDB.read(kl) != null)
                        result = result.substring(0, p0) + "<a class=\"known\" href=\"Wiki.html?page=" + kl + "\">" + kv + "</a>" + result.substring(p1 + 2);
                    else
                        result = result.substring(0, p0) + "<a class=\"unknown\" href=\"Wiki.html?page=" + kl + "&edit=Edit\">" + kv + "</a>" + result.substring(p1 + 2);
                }

            }
        
            // external links
            while ((p0 = result.indexOf("[")) >= 0) {
                p1 = result.indexOf("]", p0 + 1);
                if (p1 <= p0) break;
                kl = result.substring(p0 + 1, p1);
                if ((p = kl.indexOf(" ")) > 0) {
                    kv = kl.substring(p + 1);
                    kl = kl.substring(0, p);
                }
                // No text for the link? -> <a href="http://www.url.com/">http://www.url.com/</a>
                else {
                    kv = kl;
                }
                // replace incomplete URLs and make them point to http://peerip:port/...
                // with this feature you can access a file at DATA/HTDOCS/share/page.html
                // using the wikicode [share/page.html]
                // or a file DATA/HTDOCS/www/page.html with [www/page.html]
                // you are free to use other sub-paths of DATA/HTDOCS
                if (!((kl.indexOf("://"))>=0)) {
                    kl = "http://" + yacyCore.seedDB.mySeed.getAddress().trim() + "/" + kl;
                }
                result = result.substring(0, p0) + "<a class=\"extern\" href=\"" + kl + "\">" + kv + "</a>" + result.substring(p1 + 1);
	    }
	}
	
	//escape code ([=...=]) contributed by [MN]
	//both [= and =] in the same line
	else if(((p0 = result.indexOf("[="))>=0)&&((p1 = result.indexOf("=]"))>0)&&(!(preformatted))){
	    //if(p0 < p1){
	    String escapeText = result.substring(p0+2,p1);
	    
	    //BUGS TO BE FIXED: [=[=text=]=]  does not work properly:
	    //[=[= undx=]x=] should resolve as [= undx=]x, but resolves as [= undxx=]
	    //ALSO [=[= und =]=]   [= und =] leads to an exception
	    //
	    //handlicg cases where the text inside [= and =] also contains
	    //[= and =]. Example: [=[=...=]=]
	    //if(escapeText)
	    
	    //else{
	        result = transformLine(result.substring(0,p0).replaceAll("!esc!", "!esc!!")+"!esc!txt!"+result.substring(p1+2).replaceAll("!esc!", "!esc!!"), switchboard);
	        result = result.replaceAll("!esc!txt!", escapeText);
		result = result.replaceAll("!esc!!", "!esc!");
	    //}
	    //}
	}
	
	//start [=
	else if(((p0 = result.indexOf("[="))>=0)&&(!escapeSpan)&&(!preformatted)){
	    escape = true;    //prevent surplus line breaks
	    escaped = true;   //prevents <pre> being parsed
	    String bq = "";   //gets filled with <blockquote>s as needed
	    String escapeText = result.substring(p0+2);
	    //taking care of indented lines
	    while(result.substring(escindented,p0).startsWith(":")){
		escindented++;
		bq = bq + "<blockquote>";
	    }
	    result = transformLine(result.substring(escindented,p0).replaceAll("!esc!", "!esc!!")+"!esc!txt!", switchboard);
	    result = bq + result.replaceAll("!esc!txt!", escapeText);
	    escape = false;
	    escapeSpan = true;
	}
	
	//end =]
	else if(((p0 = result.indexOf("=]"))>=0)&&(escapeSpan)&&(!preformatted)){
	    escapeSpan = false;
	    String bq = ""; //gets filled with </blockquote>s as neede
	    String escapeText = result.substring(0,p0);
	    //taking care of indented lines
	    while(escindented > 0){
	        bq = bq + "</blockquote>";
		escindented--;
	    }
	    result = transformLine("!esc!txt!"+result.substring(p0+2).replaceAll("!esc!", "!esc!!"), switchboard);
	    result = result.replaceAll("!esc!txt!", escapeText) + bq;
	    escaped = false;
	}
	//end contrib [MN]

	//preformatted code (<pre>...</pre>) contributed by [MN]
	//implementation very similar to escape code (see above)
	//both <pre> and </pre> in the same line
	else if(((p0 = result.indexOf("&lt;pre&gt;"))>=0)&&((p1 = result.indexOf("&lt;/pre&gt;"))>0)&&(!(escaped))){
	    //if(p0 < p1){
	        String preformattedText = "<pre style=\"border:dotted;border-width:thin\">"+result.substring(p0+11,p1)+"</pre>";
                result = transformLine(result.substring(0,p0).replaceAll("!pre!", "!pre!!")+"!pre!txt!"+result.substring(p1+12).replaceAll("!pre!", "!pre!!"), switchboard);
	        result = result.replaceAll("!pre!txt!", preformattedText);
		result = result.replaceAll("!pre!!", "!pre!");
	    //}
	}
	
	//start <pre>
	else if(((p0 = result.indexOf("&lt;pre&gt;"))>=0)&&(!preformattedSpan)&&(!escaped)){
	    preformatted = true;    //prevent surplus line breaks
	    String bq ="";  //gets filled with <blockquote>s as needed
	    String preformattedText = "<pre style=\"border:dotted;border-width:thin\">"+result.substring(p0+11);
	    //taking care of indented lines
	    while(result.substring(preindented,p0).startsWith(":")){
	        preindented++;
		bq = bq + "<blockquote>";
	    }
            result = transformLine(result.substring(preindented,p0).replaceAll("!pre!", "!pre!!")+"!pre!txt!", switchboard);
            result = bq + result.replaceAll("!pre!txt!", preformattedText);
	    result = result.replaceAll("!pre!!", "!pre!");
	    preformattedSpan = true;
	}
	
	//end </pre>
	else if(((p0 = result.indexOf("&lt;/pre&gt;"))>=0)&&(preformattedSpan)&&(!escaped)){
	    preformattedSpan = false;
	    String bq = ""; //gets filled with </blockquote>s as needed
	    String preformattedText = result.substring(0,p0)+"</pre>";
            //taking care of indented lines
	    while (preindented > 0){
	        bq = bq + "</blockquote>";
                preindented--;
	    }
	    result = transformLine("!pre!txt!"+result.substring(p0+12).replaceAll("!pre!", "!pre!!"), switchboard);
	    result = result.replaceAll("!pre!txt!", preformattedText) + bq;
	    result = result.replaceAll("!pre!!", "!pre!");
	    preformatted = false;
	}
	//end contrib [MN]	
		
	if ((result.endsWith("</li>"))||(defList)||(escape)||(preformatted)) return result;
    return result + "<br>";
    }
    /*
      what we need (have):

      == New section ==
      === Subsection ===
      ==== Sub-subsection ====
      link colours: existent=green, non-existent=red
      ----
      [[wikipedia FAQ|answers]]  (first element is wiki page name, second is link print name)
      [http://www.nupedia.com Nupedia] (external link)
      [http://www.nupedia.com] (un-named external link)      
      ''Emphasize'', '''strongly''', '''''very strongly''''' (italics, bold, bold-italics)
   
      * Lists are easy to do:
      ** start every line with a star
      *** more stars means deeper levels
      # Numbered lists are also good
      ## very organized
      ## easy to follow
      ; Definition list : list of definitions
      ; item : the item's definition
      : A colon indents a line or paragraph.
      A manual newline starts a new paragraph.

      A picture: [[Image:Wiki.png]]
      [[Image:Wiki.png|right|jigsaw globe]] (floating right-side with caption)
      
      
      what we got in addition to that:
      
      [= escape characters =]
      <pre> preformatted text </pre>
      
      what would be nice in addition to that:
      || tables

    */

}