package org.simantics.excel.poi.parser.streaming;

import java.io.File;
import java.io.InputStream;
import java.util.Iterator;

import org.apache.poi.openxml4j.opc.OPCPackage;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.xssf.eventusermodel.XSSFReader;
import org.apache.poi.xssf.model.SharedStringsTable;
import org.xml.sax.ContentHandler;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.XMLReaderFactory;

public class StreamingParser {

	
	public void process(Row row) {
		
	}
	
	public void processAllSheets(File file) throws Exception {
		OPCPackage pkg = OPCPackage.open(file);
		XSSFReader r = new XSSFReader( pkg );
		SharedStringsTable sst = r.getSharedStringsTable();
		
		XSSWorkbookHandler workbookHandler = new XSSWorkbookHandler();
		XMLReader parser = fetchParser(workbookHandler);
		InputStream wb = r.getWorkbookData();
		InputSource wbSource = new InputSource(wb);
		parser.parse(wbSource);
		wb.close();
		
		
		Iterator<InputStream> sheets = r.getSheetsData();
		XSSSheetHandler sheetHandler = new XSSSheetHandler(sst) {
			@Override
			public void writeRow(Row row) {
				process(row);
			}
		};
		parser = fetchParser(sheetHandler);
		int sheetIndex = 0;
		while(sheets.hasNext()) {
			sheetHandler.setSheet(workbookHandler.getSheets().get(sheetIndex));
			InputStream sheet = sheets.next();
			InputSource sheetSource = new InputSource(sheet);
			parser.parse(sheetSource);
			sheet.close();
			sheetIndex++;
		}
	}

	public XMLReader fetchParser(ContentHandler handler) throws SAXException {
		XMLReader parser = XMLReaderFactory.createXMLReader();
		parser.setContentHandler(handler);
		return parser;
	}

}