package com.infoloop.tianting.utils;

import com.infoloop.tianting.model.common.ResponseResult;
import io.micrometer.core.instrument.util.StringUtils;
import lombok.extern.slf4j.Slf4j;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.http.MediaTypeFactory;

import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;

@Slf4j
public class ResponseUtil {

    public static void write(HttpServletResponse response, ResponseResult<?> responseDTO) {
        // 重置response
        response.setContentType("application/json");
        response.setCharacterEncoding("utf-8");
        try {
            String res = JsonUtil.writeAsJson(responseDTO);
            response.getWriter().write(res == null ? "" : res);
            response.flushBuffer();
        } catch (IOException ex) {
            log.error(ex.getMessage(), ex);
            throw new RuntimeException(ex);
        }
    }

    public static void setDownloadFileHeader(HttpServletResponse response, String fileName) {
        setDownloadFileHeader(response, fileName, null);
    }

    public static void setDownloadFileHeader(HttpServletResponse response, String fileName, Long fileSize) {
        response.setCharacterEncoding("utf-8");
        if (fileSize != null) {
            response.setHeader(HttpHeaders.CONTENT_LENGTH, String.valueOf(fileSize));
        }

        if (StringUtils.isNotEmpty(fileName)) {
            response.setHeader(HttpHeaders.CONTENT_TYPE, MediaTypeFactory.getMediaType(fileName).orElse(MediaType.APPLICATION_OCTET_STREAM) + ";charset=utf-8");
            response.setHeader(HttpHeaders.CONTENT_DISPOSITION, "attachment;filename=" + URLEncoder.encode(fileName, StandardCharsets.UTF_8).replaceAll("\\+", "%20"));
            response.setHeader(HttpHeaders.ACCESS_CONTROL_EXPOSE_HEADERS, HttpHeaders.CONTENT_DISPOSITION);
        }
    }
}