文件工具方法

type FileEncodeing =
  | "utf8"
  | "ascii"
  | "base64"
  | "binary"
  | "hex"
  | "ucs2"
  | "ucs-2"
  | "utf16le"
  | "utf-16le"
  | "utf-8"
  | "latin1"
  | undefined;

type OpenFileFlag =
  | "a+"
  | "a"
  | "ax"
  | "ax+"
  | "as"
  | "as+"
  | "r"
  | "r+"
  | "w"
  | "wx"
  | "w+"
  | "wx+"
  | undefined;

type FileType =
  | "doc"
  | "docx"
  | "xls"
  | "xlsx"
  | "ppt"
  | "pptx"
  | "pdf"
  | undefined;

const fileSystemManager = wx.getFileSystemManager();

export default {
  // 将临时文件存储为本地文件（注意：saveFile 会把临时文件移动，因此调用成功后传入的 tempFilePath 将不可用）
  saveTempFile(tempFilePath: string) {
    return new Promise((resolve, reject) => {
      fileSystemManager.saveFile({
        tempFilePath: tempFilePath,
        success(res) {
          resolve(res);
        },
        fail(err) {
          reject(err);
        },
      });
    });
  },

  // 删除本地缓存文件
  removeSavedFile(filePath: string) {
    return new Promise((resolve, reject) => {
      fileSystemManager.removeSavedFile({
        filePath: filePath,
        success(res) {
          resolve(res);
        },
        fail(err) {
          reject(err);
        },
      });
    });
  },

  // 新页面打开文件
  openDocumentInNewPage(filePath: string, fileType: FileType) {
    return new Promise((resolve, reject) => {
      wx.openDocument({
        filePath: filePath,
        fileType: fileType,
        success(res) {
          resolve(res);
        },
        fail(res) {
          reject(res);
        },
      });
    });
  },

  // 打开文件（返回文件描述符）
  openFile(filePath: string, flag: OpenFileFlag = "a+") {
    return new Promise((resolve, reject) => {
      fileSystemManager.open({
        filePath: `${wx.env.USER_DATA_PATH}` + filePath,
        flag: flag,
        success(res) {
          resolve(res);
        },
        fail(res) {
          reject(res);
        },
      });
    });
  },

  // 关闭文件（fd：文件描述符）
  closeFile(fd: any) {
    return new Promise((resolve, reject) => {
      fileSystemManager.close({
        fd: fd,
        success(res) {
          resolve(res);
        },
        fail(err) {
          reject(err);
        },
      });
    });
  },

  // 获取本地文件的文件信息。（只能用于获取已保存到本地的文件）
  // 会返回文件大小和文件保存时的时间戳，从1970/01/01 08:00:00 到该时刻的秒数
  getSavedFileList() {
    return new Promise((resolve, reject) => {
      fileSystemManager.getSavedFileList({
        success(res) {
          resolve(res);
        },
        fail(res) {
          reject(res);
        },
      });
    });
  },

  // 获取文件信息（此接口可以获取临时文件的信息，但是返回的结果中不含时间）
  // 只能返回文件大小和按照传入的 digestAlgorithm 计算得出的的文件摘要
  getFileInfo(filePath: string) {
    return new Promise((resolve, reject) => {
      fileSystemManager.getFileInfo({
        filePath: filePath,
        success(res) {
          resolve(res);
        },
        fail(res) {
          reject(res);
        },
      });
    });
  },

  // 查看是否存在对应文件（此处默认在用户目录wx.env.USER_DATA_PATH下搜索）
  hasFileOrPath(path: string) {
    console.log("查看路径：" + `${wx.env.USER_DATA_PATH}` + path);
    return new Promise((resolve, reject) => {
      fileSystemManager.access({
        path: `${wx.env.USER_DATA_PATH}` + path,
        success(res) {
          // 文件存在
          resolve(res);
        },
        fail(err) {
          reject(err);
        },
      });
    });
  },

  // 获取文件的状态信息
  // （fd）文件描述符
  fstatFile(fd: any) {
    return new Promise((resolve, reject) => {
      fileSystemManager.fstat({
        fd: fd,
        success(res) {
          console.log(res);
          resolve(res);
        },
        fail(res) {
          reject(res);
        },
      });
    });
  },

  // 读取目录下的文件列表
  readDir(path: string) {
    return new Promise((resolve, reject) => {
      fileSystemManager.readdir({
        dirPath: `${wx.env.USER_DATA_PATH}/` + path,
        success(res) {
          resolve(res);
        },
        fail(res) {
          reject(res);
        },
      });
    });
  },

  // 读取文件内容
  readFile(path: string, encoding: FileEncodeing = "utf8") {
    const fs = wx.getFileSystemManager();
    return new Promise((resolve, reject) => {
      // 打开文件
      fs.readFile({
        filePath: `${wx.env.USER_DATA_PATH}` + path,
        encoding: encoding,
        position: 0,
        success(res) {
          resolve(res);
        },
        fail(res) {
          reject(res);
        },
      });
    });
  },

  // 保存图片到本地相册
  // filePath 图片文件路径，可以是临时文件路径或永久文件路径 (本地路径) ，不支持网络路径
  saveImageToPhotosAlbum(filePath: string) {
    return new Promise((resolve, reject) => {
      wx.saveImageToPhotosAlbum({
        filePath: filePath,
        success(res) {
          resolve(res);
        },
        fail(res) {
          reject(res);
        },
      });
    });
  },

  // 保存视频到本地相册
  saveVideoToPhotosAlbum(filePath: string) {
    return new Promise((resolve, reject) => {
      wx.saveVideoToPhotosAlbum({
        filePath: filePath,
        success(res) {
          resolve(res);
        },
        fail(res) {
          reject(res);
        },
      });
    });
  },

  // 创建目录
  makeDir(path: string) {
    return new Promise((resolve, reject) => {
      fileSystemManager.mkdir({
        dirPath: `${wx.env.USER_DATA_PATH}` + path,
        // 默认如果父级目录不存在就报错
        recursive: false,
        success(res) {
          resolve(res);
        },
        fail(res) {
          reject(res);
        },
      });
    });
  },

  // 追加文件内容
  appendFile(path: string, data: any) {
    return new Promise((resolve, reject) => {
      fileSystemManager.open({
        filePath: `${wx.env.USER_DATA_PATH}` + path,
        flag: "a+",
        success(res) {
          // 写入文件
          fileSystemManager.write({
            fd: res.fd,
            data: data,
            success(res) {
              resolve(res);
            },
            fail(res) {
              reject(res);
            },
          });
        },
      });
    });
  },

  // 写文件
  writeFile(path: string, data: any) {
    return new Promise((resolve, reject) => {
      fileSystemManager.open({
        filePath: `${wx.env.USER_DATA_PATH}` + path,
        flag: "w+",
        success(res) {
          // 写入文件
          fileSystemManager.write({
            fd: res.fd,
            data: data,
            success(res) {
              resolve(res);
            },
            fail(res) {
              reject(res);
            },
          });
        },
      });
    });
  },
};