package com.zt.modules.oss.controller;

import com.zt.common.servlet.Result;
import com.zt.modules.oss.cloud.AbstractStorageService;
import io.swagger.annotations.Api;
import org.apache.tomcat.util.http.fileupload.FileUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.security.DigestInputStream;
import java.security.MessageDigest;
import java.util.Map;

@RestController
@RequestMapping("sys/oss")
@Api(tags = "文件上传")
public class chunkUploadController {
    @Autowired
    private AbstractStorageService storageService;

    @PostMapping("/upload_chunk/")
    public Result<Boolean> uploadFile(@RequestParam("file") MultipartFile file,
                                      @RequestParam("uid") String uid,
                                      @RequestParam("chunk") int chunk,
                                      @RequestParam("filter_type") String filterType,
                                      @RequestParam("fileName") String fileName,
                                      @RequestParam(value = "chunks", required = false) String chunks) {
        try {
            String tempUploadDir = storageService.getConfig().getLocalPath() + File.separator + "TEMP_UPLOAD";
            File dir = new File(tempUploadDir);
            if (!dir.exists()) {
                dir.mkdirs();
            }
            if ("undefined".equals(chunks)) {
                String filePath = tempUploadDir + File.separator + "file_" + uid;
                File destFile = new File(filePath);
                try {
                    file.transferTo(destFile);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                return Result.ok(false);
            } else {
                // 如果chunks有值，说明是分块上传的逻辑
                int numberOfChunks = Integer.parseInt(chunks);
                String uploadDir = tempUploadDir + File.separator + uid;
                File chunkdir = new File(uploadDir);
                if (!chunkdir.exists()) {
                    chunkdir.mkdirs();
                }

                String chunkFileName = uploadDir + File.separator + chunk;
                byte[] fileBytes = file.getBytes();
                try (FileOutputStream fos = new FileOutputStream(chunkFileName)) {
                    fos.write(fileBytes);
                }
                if (chunk == numberOfChunks - 1) {
                    // 所有文件块上传完成，可以将它们合并成最终文件
                    String finalFileName = tempUploadDir + File.separator + "file_" + uid;
                    File finalFile = new File(finalFileName);
                    try (FileOutputStream fos = new FileOutputStream(finalFile)) {
                        for (int i = 0; i < numberOfChunks; i++) {
                            String chunkFilePath = uploadDir + File.separator + i;
                            File chunkFile = new File(chunkFilePath);
                            try (FileInputStream fis = new FileInputStream(chunkFile)) {
                                byte[] buffer = new byte[1024];
                                int bytesRead;
                                while ((bytesRead = fis.read(buffer)) != -1) {
                                    fos.write(buffer, 0, bytesRead);
                                }
                            }
                        }
                    } catch (IOException e) {
                        e.printStackTrace();
                        return Result.ok(false);
                    } finally {
                        // 删除临时文件块目录及其内容
                        try {
                            FileUtils.deleteDirectory(chunkdir);
                        } catch (IOException e) {
                            e.printStackTrace();
                        }
                    }
                }
            }
            return Result.ok(true);
        } catch (IOException e) {
            e.printStackTrace();
            return Result.ok();
        }
    }

    @PostMapping("/upload_success/")
    public Result<Boolean> validateUploadedFile(@RequestBody Map<String, Object> fileData) {
        String name = (String) fileData.get("name");
        String uid = (String) fileData.get("uid");
        String md5 = (String) fileData.get("md5");
        int chunks = (int) fileData.get("chunks");
        String filterType = (String) fileData.get("filter_type");

        if (validateFile(name, uid, md5, chunks, filterType)) {
                return Result.ok(true);
        } else {
            return Result.ok(false);
        }
    }

    // 文件校验方法，根据文件名、uid、MD5哈希值、块数等参数进行校验
    private boolean validateFile(String name, String uid, String md5, int chunks, String filterType) {
        String filePath = storageService.getConfig().getLocalPath() + File.separator + "TEMP_UPLOAD" + File.separator + "file_" + uid;
        String calculatedMd5 = calculateFileMd5(filePath);
        if (calculatedMd5 != null && calculatedMd5.equals(md5)) {
            // 如果MD5校验通过，返回 true
            return true;
        } else {
            // 如果MD5校验失败，返回 false
            return false;
        }
    }

    private String calculateFileMd5(String filePath) {
        FileInputStream fileInputStream = null;
        DigestInputStream digestInputStream = null;

        try {
            File file = new File(filePath);
            FileInputStream fis = new FileInputStream(file);
            MessageDigest md = MessageDigest.getInstance("MD5");
            byte[] buffer = new byte[1024];
            int length = -1;
            while ((length = fis.read(buffer, 0, 1024)) != -1) {
                md.update(buffer, 0, length);
            }
            byte[] md5Bytes = md.digest();
            StringBuffer hexValue = new StringBuffer();
            for (int i = 0; i < md5Bytes.length; i++) {
                int val = ((int) md5Bytes[i]) & 0xff;
                if (val < 16)
                    hexValue.append("0");
                hexValue.append(Integer.toHexString(val));
            }
            return hexValue.toString();
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        } finally {
            try {
                if (digestInputStream != null) {
                    digestInputStream.close();
                }
                if (fileInputStream != null) {
                    fileInputStream.close();
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

}