/**
 * 本地文件选择
 */
export class FilePicker {
  /**
   * 接口是否可用
   * @returns { Boolean }
   */
  static canUse() {
    return !!(window.showDirectoryPicker && window.showOpenFilePicker)
  }

  /**
   * 选择一个目录
   * @returns { Promise<FileSystemDirectoryHandle> }
   */
  static chooseDirectory() {
    if (!this.canUse()) {
      throw new Error('Not Support showDirectoryPicker')
    }
    return window.showDirectoryPicker()
  }

  /**
   * 选择一个文件
   * @param { Boolean } multiple
   * @param { { description?: string; accept?: { [key: string]: string[]; } } } types
   * @returns { Promise<FileSystemFileHandle[]> }
   */
  static chooseFile(multiple, types) {
    if (!this.canUse()) {
      throw new Error('Not Support showOpenFilePicker')
    }
    const pickerOpts = {
      multiple,
      types,
      excludeAcceptAllOption: true
    }
    return window.showOpenFilePicker(pickerOpts)
  }

  /**
   * 判断一个文件是否在某个目录下
   * @param {FileSystemDirectoryHandle} directoryHandle
   * @param {FileSystemFileHandle} fileHandle
   */
  static async isFileInDirectory(directoryHandle, fileHandle) {
    const relativePaths = await directoryHandle.resolve(fileHandle)
    if (relativePaths === null || relativePaths.length > 1) {
      return false
    } else {
      return true
    }
  }
}