import type { UppyFile } from '@uppy/core'
import { h } from 'preact'

type $TSFixMe = any

const uploadStates = {
  STATE_ERROR: 'error',
  STATE_WAITING: 'waiting',
  STATE_PREPROCESSING: 'preprocessing',
  STATE_UPLOADING: 'uploading',
  STATE_POSTPROCESSING: 'postprocessing',
  STATE_COMPLETE: 'complete',
  STATE_PAUSED: 'paused',
}

function getUploadingState(
  isAllErrored: $TSFixMe,
  isAllComplete: $TSFixMe,
  isAllPaused: $TSFixMe,
  files: Record<string, UppyFile<any, any>> = {},
): $TSFixMe {
  if (isAllErrored) {
    return uploadStates.STATE_ERROR
  }

  if (isAllComplete) {
    return uploadStates.STATE_COMPLETE
  }

  if (isAllPaused) {
    return uploadStates.STATE_PAUSED
  }

  let state = uploadStates.STATE_WAITING
  const fileIDs = Object.keys(files)
  for (let i = 0; i < fileIDs.length; i++) {
    const { progress } = files[fileIDs[i] as keyof typeof files]
    // If ANY files are being uploaded right now, show the uploading state.
    if (progress.uploadStarted && !progress.uploadComplete) {
      return uploadStates.STATE_UPLOADING
    }
    // If files are being preprocessed AND postprocessed at this time, we show the
    // preprocess state. If any files are being uploaded we show uploading.
    if (progress.preprocess && state !== uploadStates.STATE_UPLOADING) {
      state = uploadStates.STATE_PREPROCESSING
    }
    // If NO files are being preprocessed or uploaded right now, but some files are
    // being postprocessed, show the postprocess state.
    if (
      progress.postprocess &&
      state !== uploadStates.STATE_UPLOADING &&
      state !== uploadStates.STATE_PREPROCESSING
    ) {
      state = uploadStates.STATE_POSTPROCESSING
    }
  }
  return state
}

function UploadStatus({
  files,
  i18n,
  isAllComplete,
  isAllErrored,
  isAllPaused,
  inProgressNotPausedFiles,
  newFiles,
  processingFiles,
}: $TSFixMe) {
  const uploadingState = getUploadingState(
    isAllErrored,
    isAllComplete,
    isAllPaused,
    files,
  )

  switch (uploadingState) {
    case 'uploading':
      return i18n('uploadingXFiles', {
        smart_count: inProgressNotPausedFiles.length,
      })
    case 'preprocessing':
    case 'postprocessing':
      return i18n('processingXFiles', { smart_count: processingFiles.length })
    case 'paused':
      return i18n('uploadPaused')
    case 'waiting':
      return i18n('xFilesSelected', { smart_count: newFiles.length })
    case 'complete':
      return i18n('uploadComplete')
    case 'error':
      return i18n('error')
    default:
  }
}

function PanelTopBar(props: $TSFixMe) {
  const {
    i18n,
    isAllComplete,
    hideCancelButton,
    maxNumberOfFiles,
    toggleAddFilesPanel,
    uppy,
  } = props
  let { allowNewUpload } = props
  // TODO maybe this should be done in ../Dashboard.jsx, then just pass that down as `allowNewUpload`
  if (allowNewUpload && maxNumberOfFiles) {
    // eslint-disable-next-line react/destructuring-assignment
    allowNewUpload = props.totalFileCount < props.maxNumberOfFiles
  }

  return (
    <div className="uppy-DashboardContent-bar">
      {!isAllComplete && !hideCancelButton ?
        <button
          className="uppy-DashboardContent-back"
          type="button"
          onClick={() => uppy.cancelAll()}
        >
          {i18n('cancel')}
        </button>
      : <div />}

      <div
        className="uppy-DashboardContent-title"
        role="heading"
        aria-level="1"
      >
        {/* eslint-disable-next-line react/jsx-props-no-spreading */}
        <UploadStatus {...props} />
      </div>

      {allowNewUpload ?
        <button
          className="uppy-DashboardContent-addMore"
          type="button"
          aria-label={i18n('addMoreFiles')}
          title={i18n('addMoreFiles')}
          onClick={() => toggleAddFilesPanel(true)}
        >
          <svg
            aria-hidden="true"
            focusable="false"
            className="uppy-c-icon"
            width="15"
            height="15"
            viewBox="0 0 15 15"
          >
            <path d="M8 6.5h6a.5.5 0 0 1 .5.5v.5a.5.5 0 0 1-.5.5H8v6a.5.5 0 0 1-.5.5H7a.5.5 0 0 1-.5-.5V8h-6a.5.5 0 0 1-.5-.5V7a.5.5 0 0 1 .5-.5h6v-6A.5.5 0 0 1 7 0h.5a.5.5 0 0 1 .5.5v6z" />
          </svg>
          <span className="uppy-DashboardContent-addMoreCaption">
            {i18n('addMore')}
          </span>
        </button>
      : <div />}
    </div>
  )
}

export default PanelTopBar
