export type DocumentPickerAsset = {
  uri: string
  name: string
  size?: number
  mimeType?: string
}

type DocumentPickerSuccessResult = {
  canceled: false
  assets: DocumentPickerAsset[]
}

type DocumentPickerCanceledResult = {
  canceled: true
  assets: null
}

export type DocumentPickerResult = DocumentPickerSuccessResult | DocumentPickerCanceledResult

export interface DocumentPickerOpenOptions {
  // MIME types the picker should restrict to. Hosts forward to the
  // underlying picker's `type` argument. Omitted/empty means no
  // restriction (the picker behaves as before).
  mimeTypes?: string[]
}

interface DocumentPicker {
  openAsync: (options?: DocumentPickerOpenOptions) => Promise<DocumentPickerResult>
}

export class DocumentPickerAdapter {
  openAsync: (options?: DocumentPickerOpenOptions) => Promise<DocumentPickerResult>
  configured: boolean

  constructor(methods?: DocumentPicker) {
    this.openAsync = methods?.openAsync ?? (async () => ({ canceled: true, assets: null }))
    this.configured = !!methods
  }
}