package com.luckyframe.common.utils.file;

import java.io.File;
import java.io.IOException;

import org.springframework.web.multipart.MultipartFile;

import com.luckyframe.common.exception.file.FileNameLengthLimitExceededException;
import com.luckyframe.common.exception.file.FileSizeLimitExceededException;
import com.luckyframe.common.utils.DateUtils;
import com.luckyframe.common.utils.Md5Utils;
import com.luckyframe.framework.config.LuckyFrameConfig;

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

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

    /**
     * 默认上传的地址
     */
    private static String defaultBaseDir = LuckyFrameConfig.getProfile();

    /**
     * 默认文件类型jpg
     */
    public static final String IMAGE_JPG_EXTENSION = ".jpg";
    
    /**
     * 默认驱动类型jar
     */
    public static final String DRIVEN_JAR_EXTENSION = ".jar";
    
    /**
     * 默认驱动类型python
     */
    public static final String DRIVEN_PYTHON_EXTENSION = ".py";

    private static int counter = 0;

    public static void setDefaultBaseDir(String defaultBaseDir)
    {
        FileUploadUtils.defaultBaseDir = defaultBaseDir;
    }

    public static String getDefaultBaseDir()
    {
        return defaultBaseDir;
    }

    /**
     * 以默认配置进行文件上传
     *
     * @param file 上传的文件
     * @return 文件名称
     * @throws Exception
     */
    public static final String upload(MultipartFile file) throws IOException
    {
        try
        {
            return upload(getDefaultBaseDir(), file, FileUploadUtils.IMAGE_JPG_EXTENSION);
        }
        catch (Exception e)
        {
            throw new IOException(e.getMessage(), e);
        }
    }

    /**
     * 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 final String upload(String baseDir, MultipartFile file) throws IOException
    {
        try
        {
            return upload(baseDir, file, FileUploadUtils.IMAGE_JPG_EXTENSION);
        }
        catch (Exception e)
        {
            throw new IOException(e.getMessage(), e);
        }
    }

    /**
     * 驱动上传
     * @param baseDir
     * @param file
     * @return
     * @throws FileSizeLimitExceededException
     * @throws IOException
     * @throws FileNameLengthLimitExceededException
     * @author Seagull
     * @date 2019年4月28日
     */
    public static final File uploadJar(String baseDir, MultipartFile file)
            throws FileSizeLimitExceededException, IOException, FileNameLengthLimitExceededException
    {

        int fileNamelength = file.getOriginalFilename().length();
        if (fileNamelength > FileUploadUtils.DEFAULT_FILE_NAME_LENGTH)
        {
            throw new FileNameLengthLimitExceededException(FileUploadUtils.DEFAULT_FILE_NAME_LENGTH);
        }

        assertAllowed(file);

        String fileName = file.getOriginalFilename();

        File desc = getAbsoluteFile(baseDir, baseDir + fileName);
        file.transferTo(desc);
        return desc;
    }
    
    /**
     * 文件上传
     *
     * @param baseDir 相对应用的基目录
     * @param file 上传的文件
     * @param extension 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 FileNameLengthLimitExceededException 文件名太长
     * @throws IOException 比如读写文件出错时
     */
    public static final String upload(String baseDir, MultipartFile file, String extension)
            throws FileSizeLimitExceededException, IOException, FileNameLengthLimitExceededException
    {

        int fileNamelength = file.getOriginalFilename().length();
        if (fileNamelength > FileUploadUtils.DEFAULT_FILE_NAME_LENGTH)
        {
            throw new FileNameLengthLimitExceededException(FileUploadUtils.DEFAULT_FILE_NAME_LENGTH);
        }

        assertAllowed(file);

        String fileName = extractFilename(file, extension);

        File desc = getAbsoluteFile(baseDir, baseDir + fileName);
        file.transferTo(desc);
        return fileName;
    }

    public static final String extractFilename(MultipartFile file, String extension)
    {
        String filename = file.getOriginalFilename();
        filename = DateUtils.datePath() + "/" + encodingFilename(filename) + extension;
        return filename;
    }

    private static final File getAbsoluteFile(String uploadDir, String filename) throws IOException
    {
        File desc = new File(File.separator + filename);

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

    /**
     * 编码文件名
     */
    private static final String encodingFilename(String filename)
    {
        filename = filename.replace("_", " ");
        filename = Md5Utils.hash(filename + System.nanoTime() + counter++);
        return filename;
    }

    /**
     * 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 final void assertAllowed(MultipartFile file) throws FileSizeLimitExceededException
    {
        long size = file.getSize();
        if (DEFAULT_MAX_SIZE != -1 && size > DEFAULT_MAX_SIZE)
        {
            throw new FileSizeLimitExceededException(DEFAULT_MAX_SIZE / 1024 / 1024);
        }
    }
}
