/*

  * XML2XLSGenerator.java

  *

  * Created on April 7, 2005, 5:53 PM

  */

 package org.wiztools.xml2spreadsheet;

 import org.wiztools.xml2spreadsheet.entity.CellEntity;

 import org.wiztools.xml2spreadsheet.entity.RowEntity;

 import org.wiztools.xml2spreadsheet.entity.SheetEntity;

 import org.wiztools.xml2spreadsheet.entity.WorkBookEntity;

 import org.wiztools.xml2spreadsheet.exception.XML2XLSFatalException;

 import org.wiztools.xml2spreadsheet.exception.XMLInvalidNestedElementException;

 import org.wiztools.xml2spreadsheet.exception.XMLSyntaxException;

 import java.io.IOException;

 import java.io.InputStream;

 import java.text.ParseException;

 import java.text.SimpleDateFormat;

 import java.util.Calendar;

 import java.util.Date;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import org.jdom.Document;

 import org.jdom.Element;

 import org.jdom.JDOMException;

 import org.jdom.input.SAXBuilder;

 /**

  *

  * @author subhash

  */

 public class XML2XLSGenerator {

     private WorkBookGenerationHandler wbgh;

     /** Creates a new instance of XML2XLSGenerator */

     public XML2XLSGenerator() {

     }

     private int getIntFromStr(final String str)

     throws IllegalArgumentException{

         try{

             int i = Integer.parseInt(str);

             if(i<0){

                 throw new IllegalArgumentException(

                         "Illegal attribute value: "+i);

             }

             return i;

         } catch(NumberFormatException nfe){

             throw new IllegalArgumentException(

                     "Illegal attribute value: "+str);

         }

     }

     private Date getDate(final String date, final String format)

     throws XML2XLSFatalException{

         SimpleDateFormat sdf = new SimpleDateFormat(format);

         try{

             return sdf.parse(date);

         } catch(ParseException pe){

             throw new XML2XLSFatalException(

                     "Date format ("+format+") conversion failed: "+date, pe);

         }

     }

     private Calendar getCalendar(final String date, final String format)

     throws XML2XLSFatalException{

         Date dt = getDate(date, format);

         Calendar cal = Calendar.getInstance();

         cal.setTime(dt);

         return cal;

     }

     private Document getDocument(final InputStream is)

     throws IOException, XML2XLSFatalException{

         SAXBuilder builder = new SAXBuilder();

         Document doc;

         try{

             doc = builder.build(is);

         } catch(JDOMException je){

             throw new XML2XLSFatalException("", je);

         }

         return doc;

     }

     private void processCell(final Element ecell)

     throws XML2XLSFatalException{

         List<Element> l = ecell.getChildren();

         if(l.size()>1){

             throw new XMLSyntaxException(

                     "<cell> can have only one child element: "

                     + "text|number|formula");

         }

         for(Element e: l){

             String name = e.getName();

             CellEntity cell = new CellEntity();

             if("text".equals(name)){

                 wbgh.setCellValue(e.getText());

             } else if("number".equals(name)){

                 String doubleStr = e.getTextTrim();

                 double d = -1;

                 try{

                     d = Double.parseDouble(doubleStr);

                 } catch(NumberFormatException nfe){

                     throw new XML2XLSFatalException(

                             "<number> cell value is not valid double: "

                             + doubleStr, nfe);

                 }

                 wbgh.setCellValue(d);

             } else if("formula".equals(name)){

                 String formula = e.getTextTrim();

                 if(formula == null || "".equals(formula)){

                     throw new XML2XLSFatalException(

                             "element <formula> cannot be empty");

                 }

                 wbgh.setCellFormula(formula);

             } else if("date".equals(name)){

                 String format = e.getAttributeValue("format");

                 if(format == null){

                     throw new XML2XLSFatalException(

                             "<date> element should have `format'"

                             + " attribute specified");

                 }

                 wbgh.setCellValue(getDate(e.getTextTrim(), format));

             } else if("calendar".equals(name)){

                 String format = e.getAttributeValue("format");

                 if(format == null){

                     throw new XML2XLSFatalException(

                             "<date> element should have `format'"

                             + " attribute specified");

                 }

                 wbgh.setCellValue(getCalendar(e.getTextTrim(), format));

             } else if("boolean".equals(name)){

                 String value = e.getTextTrim();

                 boolean bolVal;

                 if("true".equals(value)){

                     bolVal = true;

                 } else if("false".equals(value)){

                     bolVal = false;

                 } else{

                     throw new XML2XLSFatalException(

                             "<boolean> cell can have only true/false as value. "

                             + "The present value: " + value);

                 }

                 wbgh.setCellValue(bolVal);

             } else{

                 throw new XMLInvalidNestedElementException("cell", name);

             }

         }

     }

     private void processRow(final Element erow)

     throws XML2XLSFatalException{

         List<Element> l = erow.getChildren();

         for(Element e: l){

             String name = e.getName();

             if("cell".equals(name)){

                 String placementStr = e.getAttributeValue("placement");

                 int placement = getIntFromStr(placementStr);

                 CellEntity cell = new CellEntity();

                 String styleVal = e.getAttributeValue("style");

                 if(styleVal != null){

                     Map<String, String> attributes = new HashMap<String, String>();

                     attributes.put("style", styleVal);

                     cell.setAttributes(attributes);

                 }

                 wbgh.createCell(cell, (short)placement);

                 processCell(e);

             } else{

                 throw new XMLInvalidNestedElementException("row", name);

             }

         }

     }

     private void processMergeRegion(final Element emerge)

     throws XML2XLSFatalException{

         String reg = emerge.getAttributeValue("region");

         if(reg == null){

             throw new XML2XLSFatalException(

                     "<merge> element should have `region' attribute");

         }

         String[] arr = reg.split("\\s*,\\s*");

         if(arr.length != 4){

             throw new XML2XLSFatalException(

                     "region attribute for <merge> should have the "

                     + "format: N,N,N,N: "+reg);

         }

         int[] regions = new int[4];

         for(int i=0;i<arr.length;i++){

             int tmp = -1;

             try{

                 regions[i] = Integer.parseInt(arr[i]);

                 if(regions[i]<0){

                     throw new XML2XLSFatalException(

                             "region attribute cannot have -ve value: "+reg);

                 }

             } catch(NumberFormatException nfe){

                 throw new XML2XLSFatalException(

                         "region attribute has non-number value: "+reg);

             }

         }

         wbgh.mergeCells(regions[0],

                 (short)regions[1],

                 regions[2],

                 (short)regions[3]);

     }

     private void processColumnWidth(final Element e)

     throws XML2XLSFatalException{

         String columnStr = e.getAttributeValue("column");

         String widthStr = e.getAttributeValue("width");

         if(columnStr == null || widthStr == null){

             throw new XML2XLSFatalException(

                     "<column-width> element should have both the attributes: column and width");

         }

         short column = -1;

         short width = -1;

         try{

             column = Short.parseShort(columnStr);

             width = Short.parseShort(widthStr);

             if(column < 0 || width < 0){

                 throw new XML2XLSFatalException("column or width attribute cannot be negative");

             }

         } catch(NumberFormatException nfe){

             throw new XML2XLSFatalException("column and width attribute should be numbers");

         }

         wbgh.setColumnWidth(column, width);

     }

     private void processSheet(final Element esheet)

     throws XML2XLSFatalException{

         List<Element> l = esheet.getChildren();

         for(Element e: l){

             String name = e.getName();

             if("row".equals(name)){

                 String placementStr = e.getAttributeValue("placement");

                 int placement = getIntFromStr(placementStr);

                 RowEntity row = new RowEntity();

                 wbgh.createRow(row, placement);

                 processRow(e);

             } else if("merge".equals(name)){

                 processMergeRegion(e);

             } else if("column-width".equals(name)){

                 processColumnWidth(e);

             } else{

                 throw new XMLInvalidNestedElementException("sheet", name);

             }

         }

     }

     public void parse(final WorkBookGenerationHandler wbgh, final InputStream is)

     throws IOException, XML2XLSFatalException{

         this.wbgh = wbgh;

         Document doc = getDocument(is);

         Element root = doc.getRootElement();

         if(!"workbook".equals(root.getName())){

             throw new XMLSyntaxException("Root element should be <workbook>");

         }

         WorkBookEntity workBook = new WorkBookEntity();

         wbgh.createWorkBook(workBook);

         List<Element> l = root.getChildren();

         for(Element e: l){

             String name = e.getName();

             if("sheet".equals(name)){

                 SheetEntity sheet = new SheetEntity();

                 String namea = e.getAttributeValue("name");

                 if(namea!=null && !"".equals(namea)){

                     Map<String, String> m = new HashMap<String, String>();

                     m.put("name", namea);

                     sheet.setAttributes(m);

                     wbgh.createSheet(sheet);

                 } else{

                     wbgh.createSheet(sheet);

                 }

                 processSheet(e);

             } else{

                 throw new XMLInvalidNestedElementException("workbook", name);

             }

         }

     }

 }