package com.sckw.core.utils;

import cn.hutool.core.io.FileUtil;
import cn.hutool.core.io.file.FileNameUtil;
import cn.hutool.core.util.StrUtil;
import com.sckw.core.exception.BusinessException;
import com.sckw.core.exception.InvalidExtensionException;
import org.apache.tomcat.util.http.fileupload.impl.FileSizeLimitExceededException;
import org.springframework.web.multipart.MultipartFile;

import java.io.File;
import java.io.IOException;
import java.nio.file.Paths;
import java.util.Objects;

/**
 * 文件上传工具类
 */
public class FileUploadUtils {
    /**
     * 默认大小 50M
     */
    public static final long DEFAULT_MAX_SIZE = 50 * 1024 * 1024L;

    /**
     * 默认的文件名最大长度 100
     */
    public static final int DEFAULT_FILE_NAME_LENGTH = 100;

    /**
     * 根据文件路径上传
     *
     * @param baseDir 相对应用的基目录
     * @param file    上传的文件
     * @return 文件名称
     * @throws IOException
     */
    public static String upload(String baseDir, MultipartFile file) throws IOException {
        try {
            return upload(baseDir, file, MimeTypeUtils.DEFAULT_ALLOWED_EXTENSION);
        } catch (Exception e) {
            throw new IOException(e.getMessage(), e);
        }
    }

    /**
     * 判断MIME类型是否是允许的MIME类型
     *
     * @param extension
     * @param allowedExtension
     * @return
     */
    public static boolean isAllowedExtension(String extension, String[] allowedExtension) {
        for (String str : allowedExtension) {
            if (str.equalsIgnoreCase(extension)) {
                return true;
            }
        }
        return false;
    }

    /**
     * 文件大小校验
     *
     * @param file 上传的文件
     * @return
     * @throws FileSizeLimitExceededException 如果超出最大大小
     */
    public static void assertAllowed(MultipartFile file, String[] allowedExtension) throws FileSizeLimitExceededException, InvalidExtensionException {
        long size = file.getSize();
        if (size > DEFAULT_MAX_SIZE) {
            throw new BusinessException("文件上超限制" + DEFAULT_MAX_SIZE / 1024 / 1024);
        }

        String fileName = file.getOriginalFilename();
        String extension = getExtension(file);
        if (allowedExtension != null && !isAllowedExtension(extension, allowedExtension)) {
            if (allowedExtension == MimeTypeUtils.IMAGE_EXTENSION) {
                throw new InvalidExtensionException.InvalidImageExtensionException(allowedExtension, extension, fileName);
            } else if (allowedExtension == MimeTypeUtils.FLASH_EXTENSION) {
                throw new InvalidExtensionException.InvalidFlashExtensionException(allowedExtension, extension, fileName);
            } else if (allowedExtension == MimeTypeUtils.MEDIA_EXTENSION) {
                throw new InvalidExtensionException.InvalidMediaExtensionException(allowedExtension, extension, fileName);
            } else if (allowedExtension == MimeTypeUtils.VIDEO_EXTENSION) {
                throw new InvalidExtensionException.InvalidVideoExtensionException(allowedExtension, extension, fileName);
            } else {
                throw new InvalidExtensionException(allowedExtension, extension, fileName);
            }
        }
    }

    /**
     * 文件上传
     *
     * @param baseDir          相对应用的基目录
     * @param file             上传的文件
     * @param allowedExtension 上传文件类型
     * @return 返回上传成功的文件名
     * @throws FileSizeLimitExceededException 如果超出最大大小
     * @throws IOException                    比如读写文件出错时
     */
    public static String upload(String baseDir, MultipartFile file, String[] allowedExtension) throws FileSizeLimitExceededException, IOException, InvalidExtensionException {
        int fileNamelength = Objects.requireNonNull(file.getOriginalFilename()).length();
        if (fileNamelength > FileUploadUtils.DEFAULT_FILE_NAME_LENGTH) {
            throw new BusinessException("文件名超长" + FileUploadUtils.DEFAULT_FILE_NAME_LENGTH);
        }
        assertAllowed(file, allowedExtension);


        String fileName = extractFilename(file);

        String absPath = getAbsoluteFile(baseDir, fileName).getAbsolutePath();
        file.transferTo(Paths.get(absPath));
        return getPathFileName(fileName);
    }

    /**
     * 编码文件名
     */
    public static String extractFilename(MultipartFile file) {
        return StrUtil.format("{}/{}_{}.{}", DateUtils.datePath(), FileNameUtil.getPrefix(file.getOriginalFilename()), Seq.getId(Seq.uploadSeqType), getExtension(file));
    }

    public static File getAbsoluteFile(String uploadDir, String fileName) throws IOException {
        File desc = new File(uploadDir + File.separator + fileName);

        if (!desc.exists()) {
            if (!desc.getParentFile().exists()) {
                desc.getParentFile().mkdirs();
            }
        }
        return desc;
    }

    public static String getPathFileName(String fileName) throws IOException {
//        return CommonConstants.RESOURCE_PREFIX + "/" +  fileName;
        return fileName;
    }


    /**
     * 获取文件名的后缀
     *
     * @param file 表单文件
     * @return 后缀名
     */
    public static String getExtension(MultipartFile file) {
        String extension = FileUtil.getSuffix(file.getOriginalFilename());
        if (StringUtils.isEmpty(extension)) {
            extension = MimeTypeUtils.getExtension(Objects.requireNonNull(file.getContentType()));
        }
        return extension;
    }
}
