package de.mpiwg.itgroup.eSciDoc.Tools.DRI;

import java.awt.datatransfer.StringSelection;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.DataInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.Writer;
import java.util.HashMap;

import org.jdom.Document;
import org.jdom.Element;
import org.jdom.JDOMException;
import org.jdom.input.SAXBuilder;
import org.jdom.output.XMLOutputter;
import org.jdom.xpath.XPath;

import de.mpiwg.itgroup.eSciDoc.Tools.EScidocTools;
import de.mpiwg.itgroup.eSciDoc.utils.EScidocNameSpaceContext;

/**
 * This package loads a list of filenames and the dris belonging to them as tab delimited list.
 * It checks if the DRI are already in the index.meta, if not there are added, if there is wrong ID
 * this is eithrer corrected or an warning message is generated
 * @author dwinter
 *
 */
public class CheckAndAddDRIs {

	public class DRI{

		DRI(Document doc, String driString, Element driElement, boolean hasNameSpace){
			this.doc = doc;
			this.driString=driString;
			this.driElement=driElement;
			this.hasNameSpace=hasNameSpace;


		}
		Document doc;
		String driString;
		Element driElement;
		boolean hasNameSpace;
	}

	HashMap<String,String> fileToDri;
	String driType;

	public CheckAndAddDRIs(String fileName, String driType) throws IOException {

		this.driType=driType;

		FileInputStream fstream = new FileInputStream(fileName);

		DataInputStream in = new DataInputStream(fstream);
		BufferedReader br = new BufferedReader(new InputStreamReader(in));
		String strLine;


		// lies alle files and dris
		fileToDri = new HashMap<String, String>();
		while ((strLine = br.readLine()) != null)   {
			String[] splitted= strLine.split(("\t"));
			fileToDri.put(splitted[0], splitted[1]);
		}
		//Close the input stream
		in.close();

	}


	/**
	 * Checks if the DRIs are in the index.meta
	 */
	private void doDRI(String mode) {
		for (String key: fileToDri.keySet()){
			int result;
			DRI dri;
			try {
				dri = getDRI(key);
				result = checkDRI(dri,fileToDri.get(key));
			} catch (JDOMException e) {
				System.err.println("jdomExecption:"+key);
				continue;

			} catch (IOException e) {
				System.err.println("IOError:"+key);
				e.printStackTrace();
				continue;

			}
			if (result==0){
				System.out.println(String.format("%s\t%s\tOK", key,fileToDri.get(key)));
			} else if (result==1){
				if (mode.equals("check")){
					System.out.println(String.format("%s\t%s\tno DRI", key,fileToDri.get(key)));
				} else {
					try {					
						System.out.println(String.format("%s\t%s\tadding DRI", key,fileToDri.get(key)));
						add(key,dri,fileToDri.get(key));
					} catch (JDOMException e) {
						System.err.println("jdomExecption:"+key);
						continue;
					} catch (IOException e) {
						
						System.err.println("IOExecption:"+key);
					}
				}
			} else if (result==2){

				if (mode.equals("modify")){
					try {
						modify(key,dri,fileToDri.get(key));
					} catch (IOException e) {
						System.err.println("IOExecption:"+key);
					}
				} else {
					System.out.println(String.format("%s\t%s\twrong DRI", key,fileToDri.get(key)));
				}
			}		

		}


	

	}
	private void modify(String fileName, DRI dri, String driString) throws IOException {
		dri.driElement.setText(driString);
		writeIndexMeta(fileName, dri);

	}


	private void add(String fileName, DRI dri, String driString) throws JDOMException, IOException {
		XPath xp;
		if (dri.hasNameSpace){
			xp = EScidocTools.getESciDocXpath("//mpiwg:meta");
		} else {
			xp = EScidocTools.getESciDocXpath("//meta");
		}
		Element meta = (Element)xp.selectSingleNode(dri.doc);
		if (meta==null){
			System.err.println("NO metatag in:"+fileName);
			return;
		}

		Element el;
		if (dri.hasNameSpace){
			el = new Element("dri",EScidocNameSpaceContext.MPIWG);
		}
		else {
			el = new Element("dri");
		}

		el.setAttribute("type",this.driType);
		el.addContent(driString);
		meta.addContent(el);

		writeIndexMeta(fileName,dri);
	}


	private void writeIndexMeta(String fileName, DRI dri) throws IOException {
		
		File im = new File(fileName+"/index.meta");
		File old = new File(fileName+"/index.meta_old_DRI");
		
		if (im.renameTo(old)){
			XMLOutputter out = new XMLOutputter();
		 	
		 	String string = out.outputString(dri.doc);
		 	Writer out1 = new BufferedWriter(new OutputStreamWriter(
		 		    new FileOutputStream(fileName+"/index.meta"), "UTF-8"));

		 	
		 	out1.write(string);
		 	out1.close();
		} else {
			System.err.println("cannot rename:"+fileName);
		}
		
		
		
		
		// TODO Auto-generated method stub

	}


	private int checkDRI(DRI dri, String driString) throws JDOMException, IOException {


		if(dri.driString==null){
			return 1;
		} else if (dri.driString.equals(driString)){
			return 0;
		}

		return 2;
	}


	private DRI getDRI(String filename) throws JDOMException, IOException {
		
		
		Document doc = readIndexMeta(filename);

		XPath xpath = EScidocTools.getESciDocXpath("//meta/dri[@type=\""+driType+"\"]");


		Element res = (Element)xpath.selectSingleNode(doc);

		boolean hasNameSpace=false;
		//Try namespace
		if (res == null){
			xpath = EScidocTools.getESciDocXpath("//mpiwg:meta/mpiwg:dri[@type=\""+driType+"\"]");
			res = (Element)xpath.selectSingleNode(doc);

			if (res==null)
				return new DRI(doc,null,null,false);
			else {
				hasNameSpace=true;
			}
		}

		String txt=res.getTextTrim();



		return new DRI(doc, txt, res, hasNameSpace);
	}


	private Document readIndexMeta(String filename) throws JDOMException, IOException {
		SAXBuilder  builder = new SAXBuilder();
		Document doc = builder.build(new File(filename+"/index.meta"));
		return doc;
	}


	/**
	 * @param args
	 * @throws IOException 
	 */
	public static void main(String[] args) throws IOException {
		if (args.length <3){
			System.out.print("USAGE: command filename dri-type");
			System.exit(0);
		}

		String command = args[0];
		String fileName = args[1];
		String driType = args[2];

		final CheckAndAddDRIs ck = new CheckAndAddDRIs(fileName,driType);

		if (command.equals("check")){
			System.out.println("only checking");
			ck.doDRI("check");
		} else if (command.equals("add")){
			System.out.println("only adding");
			ck.doDRI("add");
		} else if (command.equals("modify")){
			System.out.println("adding and modify");
			ck.doDRI("modify");
		}
		else {
			System.out.println("Only the commands: check, add or modify  are allowed");
		}


	}






}