package com.seeyon.apps.assetstenant.file;

import com.seeyon.ctp.common.AppContext;
import com.seeyon.ctp.common.filemanager.manager.AttachmentManager;
import com.seeyon.ctp.common.filemanager.manager.FileManager;
import com.seeyon.ctp.common.po.filemanager.Attachment;

import javax.servlet.http.HttpServletResponse;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URLEncoder;



public class FileHandlerService {

    private AttachmentManager attachmentManager = (AttachmentManager) AppContext.getBean("attachmentManager");
    private FileManager fileManager = (FileManager) AppContext.getBean("fileManager");

    public void handleFile(String refId, HttpServletResponse response) throws Exception {
        InputStream inputStream = null;
        try {
            Attachment attachment = attachmentManager.getAttachmentByFileURL(Long.valueOf(refId));
            inputStream = fileManager.getFileInputStream(attachment.getFileUrl());

            // ⭐ 关键：重置
            response.reset();

            // ⭐ 必须设置类型
            response.setContentType("application/octet-stream");

            // ⭐ 文件名处理
            String encodedFileName = URLEncoder.encode(attachment.getFilename(), "UTF-8")
                    .replaceAll("\\+", "%20");

            response.setHeader("Access-Control-Expose-Headers", "Content-Disposition");
            response.setHeader(
                    "Content-Disposition",
                    "attachment; filename*=UTF-8''" + encodedFileName
            );

            // ⭐ 输出流
            OutputStream outputStream = response.getOutputStream();

            byte[] buffer = new byte[2048];
            int len;

            while ((len = inputStream.read(buffer)) != -1) {
                outputStream.write(buffer, 0, len);
            }

            outputStream.flush();

        } catch (Exception e) {
            e.printStackTrace(); // ❗不要吞异常
        } finally {
            try {
                if (inputStream != null) inputStream.close();
            } catch (Exception ignored) {}
        }
    }
}