package foundation.io.object;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;

import javax.servlet.http.HttpServletResponse;

import foundation.dao.DataWriter;
import foundation.handler.LetterWriter;
import foundation.handler.ResultPool;
import foundation.json.JSONWriter;

public class DownloadWriter extends LetterWriter {

	private HttpServletResponse response;
	
	public DownloadWriter(DataWriter dataWriter) {
		ResultPool resultPool = dataWriter.getResultPool();
		
		this.response = resultPool.getResponse();
		resultPool.setFireReplay(false);
	}

	public void write(File file, String fileName, DownloadAction action) throws IOException {
		writeHeader(fileName, action);
		
		OutputStream outputStream = response.getOutputStream();
		
		try {
			if (file != null && file.exists()) {
				InputStream inputStream = new FileInputStream(file);
				try {
					byte[] buffer = new byte[1024]; int numberRead = 0;
					
					while ((numberRead = inputStream.read(buffer)) != -1) {  
						outputStream.write(buffer, 0, numberRead);       
				    }  
				}
				finally {
					inputStream.close();
				}				
			}
			else {
				String message = "foundation/file " + fileName + " not find";
				outputStream.write(message.getBytes());
			}
		}
		finally {
			outputStream.flush();
			outputStream.close();
		}
	}
	
	public void write(String name, StringBuilder content, DownloadAction action) throws IOException {
		writeHeader(name, action);
		
		PrintWriter writer = response.getWriter();
		try {
			writer.write(content.toString());
		}
		finally {
			if (writer != null) {
				writer.flush();
				writer.close();
			}
		}
	}

	private void writeHeader(String name, DownloadAction action) throws UnsupportedEncodingException {
		if (action == null) {
			action = DownloadAction.SaveAs;
		}
		
		String prefix = "";
		
		if (DownloadAction.SaveAs == action) {
			response.setHeader("Content-Type", "application/octet-stream");
			prefix = "attachment;";
		}
		else if (DownloadAction.AsJPEG == action) {
			response.setHeader("Content-Type", "image/jpeg");
		}
		else if (DownloadAction.AsPng == action) {
			response.setHeader("Content-Type", "image/png");
		}
		else if (DownloadAction.AsGIF == action) {
			response.setHeader("Content-Type", "image/gif");
		}
		else if (DownloadAction.AsBmp == action) {
			response.setHeader("Content-Type", "image/bmp");
		}
		else if (DownloadAction.AsExcel == action) {
			response.setHeader("Content-Type", "application/vnd.ms-excel");
		}
		else if (DownloadAction.AsWord == action) {
			response.setHeader("Content-Type", "application/msword");
		}		
		else if (DownloadAction.AsPowerPoint == action) {
			response.setHeader("Content-Type", "application/x-ppt");
		}
		else if (DownloadAction.AsPDF == action) {
			response.setHeader("Content-Type", "application/pdf");
		}		
		else if (DownloadAction.ASTexT == action) {
			response.setHeader("Content-Type", "text/plain");
		}		
		
		response.setHeader("Content-Disposition", prefix + "filename=" + JSONWriter.encodeValue(name));
	}

}