package org.jeecg.common.util;

import org.jeecg.common.api.vo.FileUploadResult;
import org.jeecg.common.exception.ExceptionCast;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

@Component
public class FileUtil {

	private static String fileUploadFolder;

	@SuppressWarnings("unused")
	private static String uploadType;

	@Value(value = "${jeecg.path.upload}")
	public void setFileUploadFolder(String fileUploadFolder) {
		FileUtil.fileUploadFolder = fileUploadFolder;
	}

	@Value(value = "${jeecg.uploadType}")
	public void setUploadType(String uploadType) {
		FileUtil.uploadType = uploadType;
	}

	public static FileUploadResult uploadFile(MultipartFile file) {
		if (file == null || file.isEmpty())
			return null;
		String fileName = file.getOriginalFilename();
		String suffix = getFileSuffix(fileName);
		Date currentDate = DateUtils.getDate();
		String monthStr = DateUtils.date2Str(currentDate, DateUtils.monthFormat.get());
		// 相对路径
		String relativePath = "/" + monthStr + "/" + DateUtils.getDayStr(currentDate) + "/";
		// 绝对路径
		String absolutePath = fileUploadFolder + "/" + monthStr + "/" + DateUtils.getDayStr(currentDate) + "/";
		String fileNameNonSuffix = getFilenameNonSuffix(fileName);
		if (fileNameNonSuffix == null)
			return null;
		// 获取文件加密名称 1 保证文件唯一 不存在覆盖问题 2 目录下保存文件加密名称 去除文件关键信息
		String encodeFileName = SHA256Util.getSHA256Str(fileNameNonSuffix + System.currentTimeMillis()) + "." + suffix;
		Long fileSize = file.getSize();
		boolean b = uploadFile(file, absolutePath, encodeFileName);
		if (!b)
			return null;
		FileUploadResult dto = new FileUploadResult();
		dto.setFileName(fileNameNonSuffix);
		dto.setFileEncodeName(encodeFileName);
		dto.setFilePath(relativePath + encodeFileName);
		dto.setFileSize(fileSize);
		dto.setFileSuffix(suffix);
		return dto;
	}

	/**
	 * @param filePath 路径
	 * @param fileName 文件名
	 */
	public static void deleteFile(String filePath, String fileName) {
		String absolutePath = fileUploadFolder + "/" + filePath + "/";
		File targetFile = new File(absolutePath, fileName);
		targetFile.deleteOnExit();
	}

	public static void downLoadFile(HttpServletResponse response, String fileName, String filePath, String toFileName) {
		String absolutePath = fileUploadFolder + filePath;
		File file = new File(absolutePath, fileName);
		if (file.exists()) {
			byte[] buffer = new byte[1024];
			FileInputStream fis = null;
			BufferedInputStream bis = null;
			try {
				response.setHeader("Content-Type", "application/octet-stream;charset=utf-8"); // 告诉浏览器输出内容为流
				// response.setHeader("Content-Disposition", "attachment;fileName="+ new
				// String(toFileName.getBytes("UTF-8"),"ISO-8859-1"));
				response.setHeader("Content-Disposition",
						"attachment;fileName=" + URLEncoder.encode(toFileName, "UTF-8"));
				fis = new FileInputStream(file);
				bis = new BufferedInputStream(fis);
				OutputStream os = response.getOutputStream();
				int i = bis.read(buffer);
				while (i != -1) {
					os.write(buffer, 0, i);
					i = bis.read(buffer);
				}
				os.flush();
			} catch (Exception e) {
				e.printStackTrace();
			} finally {
				if (bis != null) {
					try {
						bis.close();
					} catch (IOException e) {
					}
				}
				if (fis != null) {
					try {
						fis.close();
					} catch (IOException e) {
					}
				}
			}
		} else {
			ExceptionCast.cast("文件不存在");
		}
	}

	public static void downLoadFile(HttpServletResponse response, String filePath, String toFileName) {
		String absolutePath = fileUploadFolder + filePath;
		File file = new File(absolutePath);
		if (file.exists()) {
			byte[] buffer = new byte[1024];
			FileInputStream fis = null;
			BufferedInputStream bis = null;
			try {
				response.setHeader("Content-Type", "application/octet-stream;charset=utf-8"); // 告诉浏览器输出内容为流
				// response.setHeader("Content-Disposition", "attachment;fileName="+ new
				// String(toFileName.getBytes("UTF-8"),"ISO-8859-1"));
				response.setHeader("Content-Disposition",
						"attachment;fileName=" + URLEncoder.encode(toFileName, "UTF-8"));
				fis = new FileInputStream(file);
				bis = new BufferedInputStream(fis);
				OutputStream os = response.getOutputStream();
				int i = bis.read(buffer);
				while (i != -1) {
					os.write(buffer, 0, i);
					i = bis.read(buffer);
				}
				os.flush();
			} catch (Exception e) {
				e.printStackTrace();
			} finally {
				if (bis != null) {
					try {
						bis.close();
					} catch (IOException e) {
					}
				}
				if (fis != null) {
					try {
						fis.close();
					} catch (IOException e) {
					}
				}
			}
		} else {
			ExceptionCast.cast("文件不存在");
		}
	}

	/**
	 * 上传文件工具类
	 * 
	 * @param multipartFile
	 * @param path
	 * @param fileNewName   新的文件名
	 * @return
	 */
	public static boolean uploadFile(MultipartFile multipartFile, String path, String fileNewName) {
		File targetFile = new File(path, fileNewName);
		if (!targetFile.getParentFile().exists()) {
			targetFile.getParentFile().mkdirs();
		}
		try {
			multipartFile.transferTo(targetFile);
			return true;
		} catch (Exception e) {
			e.printStackTrace();
			return false;
		}
	}

	/**
	 * 获取文件后缀 无后缀文件返回NULL
	 * 
	 * @param fileName
	 * @return
	 */
	public static String getFileSuffix(String fileName) {
		if (fileName.contains(".")) {
			String suffix = fileName.substring(fileName.lastIndexOf('.') + 1);
			return suffix;
		} else {
			return null;
		}

	}

	/**
	 * 获取文件名 不带后缀和点号
	 * 
	 * @param fileName
	 * @return
	 */
	public static String getFilenameNonSuffix(String fileName) {
		if (fileName.contains(".")) {
			String filename = fileName.substring(0, fileName.lastIndexOf('.'));
			return filename;
		} else {
			return fileName;
		}

	}

	public static List<String> readFile(String fileEncodeName, String filePath) {
		String absolutePath = fileUploadFolder + filePath;
		File file = new File(absolutePath, fileEncodeName);
		if (!file.exists() || file.isDirectory())
			return null;
		String charset = checkFileEncode(file);
		if (charset == null)
			return null;
		List<String> readList = new ArrayList<>();
		String tempString = null;
		BufferedReader reader = null;
		try {
			reader = new BufferedReader(new InputStreamReader(new FileInputStream(file), charset));
			while ((tempString = reader.readLine()) != null) {
				readList.add(tempString);
			}
			if (readList.isEmpty())
				return null;
			return readList;
		} catch (Exception e) {
			e.printStackTrace();
			return null;
		} finally {
			if (reader != null) {
				try {
					reader.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		}
	}

	private static String checkFileEncode(File file) {
		String charset = "GBK";
		byte[] first3Bytes = new byte[3];
		BufferedInputStream bis = null;
		try {
			boolean checked = false;
			bis = new BufferedInputStream(new FileInputStream(file));
			bis.mark(0);
			int read = bis.read(first3Bytes, 0, 3);
			if (read == -1)
				return charset;
			if (first3Bytes[0] == (byte) 0xFF && first3Bytes[1] == (byte) 0xFE) {
				charset = "UTF-16LE";
				checked = true;
			} else if (first3Bytes[0] == (byte) 0xFE && first3Bytes[1] == (byte) 0xFF) {
				charset = "UTF-16BE";
				checked = true;
			} else if (first3Bytes[0] == (byte) 0xEF && first3Bytes[1] == (byte) 0xBB
					&& first3Bytes[2] == (byte) 0xBF) {
				charset = "UTF-8";
				checked = true;
			}
			bis.reset();
			if (!checked) {
				while ((read = bis.read()) != -1) {
					if (read >= 0xF0)
						break;
					if (0x80 <= read && read <= 0xBF) // 单独出现BF以下的，也算是GBK
						break;
					if (0xC0 <= read && read <= 0xDF) {
						read = bis.read();
						if (0x80 <= read && read <= 0xBF) // 双字节 (0xC0 - 0xDF) (0x80 - 0xBF),也可能在GBK编码内  
							continue;
						else
							break;
					} else if (0xE0 <= read && read <= 0xEF) {
						// 也有可能出错，但是几率较小
						read = bis.read();
						if (0x80 <= read && read <= 0xBF) {
							read = bis.read();
							if (0x80 <= read && read <= 0xBF) {
								charset = "UTF-8";
								break;
							} else
								break;
						} else {
							break;
						}
					}
				}
			}
			return charset;
		} catch (Exception e) {
			return null;
		} finally {
			if (bis != null) {
				try {
					bis.close();
				} catch (IOException e) {
				}
			}
		}

	}

}