package froala.editor.utils.view;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.net.URLEncoder;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.view.AbstractView;

import egovframework.com.cmm.util.EgovResourceCloseHelper;

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

	@Override
	protected void renderMergedOutputModel(Map<String, Object> model,
			HttpServletRequest request, HttpServletResponse response) throws IOException {
		String path = (String) model.get("path");

		Path source = Paths.get(path);

		// 응답의 타입이 이미지임을 알려줍니다.
		response.setContentType(Files.probeContentType(source));

		// 한글 파일명일 경우를 위해 파일명 인코딩
		String filename = (String) model.get("origin_file_nm");
		if (StringUtils.isBlank(filename)) {
			filename = source.getFileName().toString();
		}
//		String filename = source.getFileName().toString();
		String userAgent = request.getHeader("User-Agent");
		String conVstr = null;

		if (userAgent.contains("MSIE")) {
			conVstr = URLEncoder.encode(filename,"UTF-8");
		} else if (userAgent.contains("Trident")) {
			conVstr = URLEncoder.encode(filename,"UTF-8");
		} else if(userAgent.contains("Chrome")) {
			conVstr = new String(filename.getBytes("UTF-8"), "ISO-8859-1");
		} else if(userAgent.contains("Opera")) {
			conVstr = new String(filename.getBytes("UTF-8"), "ISO-8859-1");
		} else if (userAgent.contains("Mozilla")){
			conVstr = new String(filename.getBytes("UTF-8"), "ISO-8859-1");
		} else {
			conVstr = new String(filename.getBytes("UTF-8"), "ISO-8859-1");
		}

		// 웹브라우저 상에서 이미지 저장시 파일명을 지정합니다.
		response.setHeader("Content-Disposition", "attachment; filename=" + conVstr + ";");

		// 파일로부터 byte를 읽음
		byte[] bytes = readFile(path);
		if (bytes != null) {
			write(response, bytes);
		}
	}

	/**
	 * 파일로부터 byte 배열 읽어오기
	 */
	private byte[] readFile(String path) throws IOException {
		BufferedInputStream bis = null;
		byte[] bytes = null;
		FileInputStream fis = null;
		try {
			File file = new File(path);
			if (Boolean.FALSE.equals(file.exists())) {
				return null;
			}
			fis = new FileInputStream(path);
			bis = new BufferedInputStream(fis);
			int length = bis.available();
			bytes = new byte[length];
			bis.read(bytes);
	    }
	    catch(IOException e){
	    	LOGGER.error("fail to process imageView readFile {}", e);
	    } finally {
	    	EgovResourceCloseHelper.close(fis, bis);
		}

		return bytes;
	}

	/**
	 * 응답 OutputStream에 파일 내용 쓰기
	 */
	private void write(HttpServletResponse response, byte[] bytes) throws IOException {
		OutputStream output = response.getOutputStream();
		output.write(bytes);
		output.flush();
	}
}