package kr.wisestone.owl.web.view;


import kr.wisestone.owl.annotation.Viewer;
import kr.wisestone.owl.vo.AttachedFileVo;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.util.FileCopyUtils;
import org.springframework.web.servlet.view.AbstractView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.net.URLEncoder;
import java.util.Map;

@Viewer
public class FileDownloadView extends AbstractView {
    private static final Logger LOGGER = LoggerFactory.getLogger(FileDownloadView.class);

    public FileDownloadView() {
        super.setContentType("application/octet-stream");
    }

    @Override
    protected void renderMergedOutputModel(Map<String, Object> model, HttpServletRequest request, HttpServletResponse response) throws Exception {
        AttachedFileVo attachedFileVo = (AttachedFileVo) model.get("fileDownloadTarget");
        response.setContentType(super.getContentType());
        response.setContentLength(attachedFileVo.getSize().intValue());
        response.setHeader("Content-Transfer-Encoding", "binary");
        String userAgent = request.getHeader("User-Agent");

        // attachment; 가 붙으면 IE의 경우 무조건 다운로드창이 뜬다. 상황에 따라 써야한다.
        if (userAgent != null && userAgent.indexOf("MSIE 5.5") > -1) {
            // MS IE 5.5 이하
            response.setHeader("Content-Disposition", String.format("filename=%s;", URLEncoder.encode(attachedFileVo.getName(), "UTF-8")));
        } else if ((userAgent != null && userAgent.indexOf("MSIE") > -1) || userAgent.indexOf("Trident") > -1) {
            // MS IE (보통은 6.x 이상 가정)
            response.setHeader("Content-Disposition", String.format("attachment; filename=%s;", URLEncoder.encode(attachedFileVo.getName(), "UTF-8")));
        } else {
            // 모질라, 오페라, 크롬 등
            response.setHeader("Content-Disposition", String.format("attachment; filename=\"%s\";", new String(attachedFileVo.getName().getBytes("UTF-8"), "latin1")));
        }

        OutputStream outputStream = null;
        InputStream inputStream = null;

        try {
            outputStream = response.getOutputStream();
            inputStream = new ByteArrayInputStream(attachedFileVo.getBytes());
            FileCopyUtils.copy(inputStream, outputStream);
        } catch (IOException ioe) {
            LOGGER.error("다운로드 파일 제어 중 오류가 발생했습니다.", ioe);

            throw ioe;
        } finally {
            if (inputStream != null)
                inputStream.close();

            if (outputStream != null) {
                outputStream.flush();
                outputStream.close();
            }
        }
    }
}