package org.infohazard.maverick.opt.view;

import java.io.ByteArrayOutputStream;
import java.io.IOException;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.fop.apps.Driver;
import org.apache.fop.apps.FOPException;
import org.infohazard.maverick.flow.View;
import org.infohazard.maverick.util.FakeHttpServletResponse;
import org.xml.sax.InputSource;

public class FopView implements View {

	/**
	 * Source url of the document.
	 */
	protected String path;

	public FopView(String path) {
		this.path = path;
	}
	
	/**
	 * @see View#go(Object, HttpServletRequest, HttpServletResponse)
	 */
	public void go(Object model, HttpServletRequest request, HttpServletResponse response)
		throws IOException, ServletException {

		// Load document into fake response and then pipe the output throught fop.

		// We are dependent upon the 2.3 Servlet API because we need to be
		// able to use a wrapper, which is not allowed by 2.2.

		FakeHttpServletResponse fakeResponse = new FakeHttpServletResponse(response);
		RequestDispatcher rd = request.getRequestDispatcher(path);
		rd.include(request, fakeResponse);
		String result = fakeResponse.getOutputAsString();
		
		ByteArrayOutputStream baos = new ByteArrayOutputStream();
		Driver driver = new Driver();
		driver.setRenderer(Driver.RENDER_PDF);
		driver.setInputSource(new InputSource(fakeResponse.getOutputAsReader()));
		driver.setOutputStream(baos);
		try {
			driver.run();
		} catch (FOPException ex) {
			throw new ServletException(ex);	
		}
		
		response.setContentType("application/pdf");
		response.setContentLength(baos.size());
		baos.writeTo(response.getOutputStream());
	}

}