import type { FC } from 'react'
import type { ChildChunkDetail, ChunkingMode } from '@/models/datasets'
import { cn } from '@langgenius/dify-ui/cn'
import {
  RiCloseLine,
  RiCollapseDiagonalLine,
  RiExpandDiagonalLine,
} from '@remixicon/react'
import * as React from 'react'
import { useMemo, useState } from 'react'
import { useTranslation } from 'react-i18next'
import Divider from '@/app/components/base/divider'
import { useEventEmitterContextContext } from '@/context/event-emitter'
import { formatNumber } from '@/utils/format'
import { formatTime } from '@/utils/time'
import ActionButtons from './common/action-buttons'
import ChunkContent from './common/chunk-content'
import Dot from './common/dot'
import { SegmentIndexTag } from './common/segment-index-tag'
import { useSegmentListContext } from './index'

type IChildSegmentDetailProps = {
  chunkId: string
  childChunkInfo?: Partial<ChildChunkDetail> & { id: string }
  onUpdate: (segmentId: string, childChunkId: string, content: string) => void
  onCancel: () => void
  docForm: ChunkingMode
}

/**
 * Show all the contents of the segment
 */
const ChildSegmentDetail: FC<IChildSegmentDetailProps> = ({
  chunkId,
  childChunkInfo,
  onUpdate,
  onCancel,
  docForm,
}) => {
  const { t } = useTranslation()
  const [content, setContent] = useState(childChunkInfo?.content || '')
  const { eventEmitter } = useEventEmitterContextContext()
  const [loading, setLoading] = useState(false)
  const fullScreen = useSegmentListContext(s => s.fullScreen)
  const toggleFullScreen = useSegmentListContext(s => s.toggleFullScreen)

  eventEmitter?.useSubscription((v) => {
    if (v === 'update-child-segment')
      setLoading(true)
    if (v === 'update-child-segment-done')
      setLoading(false)
  })

  const handleCancel = () => {
    onCancel()
  }

  const handleSave = () => {
    onUpdate(chunkId, childChunkInfo?.id || '', content)
  }

  const wordCountText = useMemo(() => {
    const count = content.length
    return `${formatNumber(count)} ${t('segment.characters', { ns: 'datasetDocuments', count })}`
  }, [content.length])

  const EditTimeText = useMemo(() => {
    const timeText = formatTime({
      date: (childChunkInfo?.updated_at ?? 0) * 1000,
      dateFormat: `${t('segment.dateTimeFormat', { ns: 'datasetDocuments' })}`,
    })
    return `${t('segment.editedAt', { ns: 'datasetDocuments' })} ${timeText}`
  }, [childChunkInfo?.updated_at])

  return (
    <div className="flex h-full flex-col">
      <div className={cn('flex items-center justify-between', fullScreen ? 'border border-divider-subtle py-3 pr-4 pl-6' : 'pt-3 pr-3 pl-4')}>
        <div className="flex flex-col">
          <div className="system-xl-semibold text-text-primary">{t('segment.editChildChunk', { ns: 'datasetDocuments' })}</div>
          <div className="flex items-center gap-x-2">
            <SegmentIndexTag positionId={childChunkInfo?.position || ''} labelPrefix={t('segment.childChunk', { ns: 'datasetDocuments' }) as string} />
            <Dot />
            <span className="system-xs-medium text-text-tertiary">{wordCountText}</span>
            <Dot />
            <span className="system-xs-medium text-text-tertiary">
              {EditTimeText}
            </span>
          </div>
        </div>
        <div className="flex items-center">
          {fullScreen && (
            <>
              <ActionButtons
                handleCancel={handleCancel}
                handleSave={handleSave}
                loading={loading}
                isChildChunk={true}
              />
              <Divider type="vertical" className="mr-2 ml-4 h-3.5 bg-divider-regular" />
            </>
          )}
          <button
            type="button"
            aria-label={t(fullScreen ? 'operation.zoomOut' : 'operation.zoomIn', { ns: 'common' })}
            className="mr-1 flex size-8 cursor-pointer items-center justify-center border-none bg-transparent p-1.5"
            onClick={toggleFullScreen}
          >
            {fullScreen
              ? <RiCollapseDiagonalLine className="size-4 text-text-tertiary" aria-hidden="true" />
              : <RiExpandDiagonalLine className="size-4 text-text-tertiary" aria-hidden="true" />}
          </button>
          <button
            type="button"
            aria-label={t('operation.close', { ns: 'common' })}
            className="flex size-8 cursor-pointer items-center justify-center border-none bg-transparent p-1.5"
            onClick={onCancel}
          >
            <RiCloseLine className="size-4 text-text-tertiary" aria-hidden="true" />
          </button>
        </div>
      </div>
      <div className={cn('flex w-full grow', fullScreen ? 'flex-row justify-center px-6 pt-6' : 'px-4 py-3')}>
        <div className={cn('h-full overflow-hidden break-all whitespace-pre-line', fullScreen ? 'w-1/2' : 'w-full')}>
          <ChunkContent
            docForm={docForm}
            question={content}
            onQuestionChange={content => setContent(content)}
            isEditMode={true}
          />
        </div>
      </div>
      {!fullScreen && (
        <div className="flex items-center justify-end border-t border-t-divider-subtle p-4 pt-3">
          <ActionButtons
            handleCancel={handleCancel}
            handleSave={handleSave}
            loading={loading}
            isChildChunk={true}
          />
        </div>
      )}
    </div>
  )
}

export default React.memo(ChildSegmentDetail)