'use client'
import type { FC } from 'react'
import type { FileItem } from '@/models/datasets'
import { Button } from '@langgenius/dify-ui/button'
import { cn } from '@langgenius/dify-ui/cn'
import { toast } from '@langgenius/dify-ui/toast'
import { RiDeleteBinLine } from '@remixicon/react'
import * as React from 'react'
import { useCallback, useEffect, useMemo, useRef, useState } from 'react'
import { useTranslation } from 'react-i18next'
import { getFileUploadErrorMessage } from '@/app/components/base/file-uploader/utils'
import { Csv as CSVIcon } from '@/app/components/base/icons/src/public/files'
import SimplePieChart from '@/app/components/base/simple-pie-chart'
import useTheme from '@/hooks/use-theme'
import { upload } from '@/service/base'
import { useFileUploadConfig } from '@/service/use-common'
import { Theme } from '@/types/app'

type Props = Readonly<{
  file: FileItem | undefined
  updateFile: (file?: FileItem) => void
}>
const CSVUploader: FC<Props> = ({ file, updateFile }) => {
  const { t } = useTranslation()
  const [dragging, setDragging] = useState(false)
  const dropRef = useRef<HTMLDivElement>(null)
  const dragRef = useRef<HTMLDivElement>(null)
  const fileUploader = useRef<HTMLInputElement>(null)
  const { data: fileUploadConfigResponse } = useFileUploadConfig()
  const fileUploadConfig = useMemo(() => fileUploadConfigResponse ?? {
    file_size_limit: 15,
  }, [fileUploadConfigResponse])
  type UploadResult = Awaited<ReturnType<typeof upload>>
  const fileUpload = useCallback(async (fileItem: FileItem): Promise<FileItem> => {
    fileItem.progress = 0
    const formData = new FormData()
    formData.append('file', fileItem.file)
    const onProgress = (e: ProgressEvent) => {
      if (e.lengthComputable) {
        const progress = Math.floor(e.loaded / e.total * 100)
        updateFile({
          ...fileItem,
          progress,
        })
      }
    }
    return upload({
      xhr: new XMLHttpRequest(),
      data: formData,
      onprogress: onProgress,
    }, false, undefined, '?source=datasets')
      .then((res: UploadResult) => {
        const updatedFile = Object.assign({}, fileItem.file, {
          id: res.id,
          ...(res as Partial<File>),
        }) as File
        const completeFile: FileItem = {
          fileID: fileItem.fileID,
          file: updatedFile,
          progress: 100,
        }
        updateFile(completeFile)
        return Promise.resolve({ ...completeFile })
      })
      .catch((e) => {
        const errorMessage = getFileUploadErrorMessage(e, t('stepOne.uploader.failed', { ns: 'datasetCreation' }), t)
        toast.error(errorMessage)
        const errorFile = {
          ...fileItem,
          progress: -2,
        }
        updateFile(errorFile)
        return Promise.resolve({ ...errorFile })
      })
      .finally()
  }, [t, updateFile])
  const uploadFile = useCallback(async (fileItem: FileItem) => {
    await fileUpload(fileItem)
  }, [fileUpload])
  const initialUpload = useCallback((file?: File) => {
    if (!file)
      return false
    const newFile: FileItem = {
      fileID: `file0-${Date.now()}`,
      file,
      progress: -1,
    }
    updateFile(newFile)
    uploadFile(newFile)
  }, [updateFile, uploadFile])
  const handleDragEnter = (e: DragEvent) => {
    e.preventDefault()
    e.stopPropagation()
    if (e.target !== dragRef.current)
      setDragging(true)
  }
  const handleDragOver = (e: DragEvent) => {
    e.preventDefault()
    e.stopPropagation()
  }
  const handleDragLeave = (e: DragEvent) => {
    e.preventDefault()
    e.stopPropagation()
    if (e.target === dragRef.current)
      setDragging(false)
  }
  const handleDrop = (e: DragEvent) => {
    e.preventDefault()
    e.stopPropagation()
    setDragging(false)
    if (!e.dataTransfer)
      return
    const files = Array.from(e.dataTransfer.files)
    if (files.length > 1) {
      toast.error(t('stepOne.uploader.validation.count', { ns: 'datasetCreation' }))
      return
    }
    initialUpload(files[0])
  }
  const selectHandle = () => {
    if (fileUploader.current)
      fileUploader.current.click()
  }
  const removeFile = () => {
    if (fileUploader.current)
      fileUploader.current.value = ''
    updateFile()
  }
  const getFileType = (currentFile: File) => {
    if (!currentFile)
      return ''
    const arr = currentFile.name.split('.')
    return arr[arr.length - 1]
  }
  const isValid = useCallback((file?: File) => {
    if (!file)
      return false
    const { size } = file
    const ext = `.${getFileType(file)}`
    const isValidType = ext.toLowerCase() === '.csv'
    if (!isValidType)
      toast.error(t('stepOne.uploader.validation.typeError', { ns: 'datasetCreation' }))
    const isValidSize = size <= fileUploadConfig.file_size_limit * 1024 * 1024
    if (!isValidSize)
      toast.error(t('stepOne.uploader.validation.size', { ns: 'datasetCreation', size: fileUploadConfig.file_size_limit }))
    return isValidType && isValidSize
  }, [fileUploadConfig, t])
  const fileChangeHandle = (e: React.ChangeEvent<HTMLInputElement>) => {
    const currentFile = e.target.files?.[0]
    if (!isValid(currentFile))
      return
    initialUpload(currentFile)
  }
  const { theme } = useTheme()
  const chartColor = useMemo(() => theme === Theme.dark ? '#5289ff' : '#296dff', [theme])
  useEffect(() => {
    dropRef.current?.addEventListener('dragenter', handleDragEnter)
    dropRef.current?.addEventListener('dragover', handleDragOver)
    dropRef.current?.addEventListener('dragleave', handleDragLeave)
    dropRef.current?.addEventListener('drop', handleDrop)
    return () => {
      dropRef.current?.removeEventListener('dragenter', handleDragEnter)
      dropRef.current?.removeEventListener('dragover', handleDragOver)
      dropRef.current?.removeEventListener('dragleave', handleDragLeave)
      dropRef.current?.removeEventListener('drop', handleDrop)
    }
  }, [])
  return (
    <div className="mt-6">
      <input ref={fileUploader} style={{ display: 'none' }} type="file" id="fileUploader" accept=".csv" onChange={fileChangeHandle} />
      <div ref={dropRef}>
        {!file && (
          <div className={cn('flex h-20 items-center rounded-xl border border-dashed border-components-panel-border bg-components-panel-bg-blur text-sm font-normal', dragging && 'border border-divider-subtle bg-components-panel-on-panel-item-bg-hover')}>
            <div className="flex w-full items-center justify-center space-x-2">
              <CSVIcon className="shrink-0" />
              <div className="text-text-secondary">
                {t('list.batchModal.csvUploadTitle', { ns: 'datasetDocuments' })}
                <button
                  type="button"
                  className="inline cursor-pointer border-none bg-transparent p-0 text-left text-text-accent focus-visible:ring-1 focus-visible:ring-components-input-border-active focus-visible:outline-hidden"
                  onClick={selectHandle}
                >
                  {t('list.batchModal.browse', { ns: 'datasetDocuments' })}
                </button>
              </div>
            </div>
            {dragging && <div ref={dragRef} className="absolute top-0 left-0 size-full" />}
          </div>
        )}
        {file && (
          <div className={cn('group flex h-20 items-center rounded-xl border border-components-panel-border bg-components-panel-bg-blur px-6 text-sm font-normal', 'hover:border-divider-subtle hover:bg-components-panel-on-panel-item-bg-hover')}>
            <CSVIcon className="shrink-0" />
            <div className="ml-2 flex w-0 grow">
              <span className="max-w-[calc(100%-30px)] overflow-hidden text-ellipsis whitespace-nowrap text-text-primary">{file.file.name.replace(/.csv$/, '')}</span>
              <span className="shrink-0 text-text-secondary">.csv</span>
            </div>
            <div className="hidden items-center group-hover:flex">
              {(file.progress < 100 && file.progress >= 0) && (
                <>
                  <SimplePieChart percentage={file.progress} stroke={chartColor} fill={chartColor} animationDuration={0} />
                  <div className="mx-2 h-4 w-px bg-text-secondary" />
                </>
              )}
              <Button onClick={selectHandle}>{t('stepOne.uploader.change', { ns: 'datasetCreation' })}</Button>
              <div className="mx-2 h-4 w-px bg-text-secondary" />
              <button
                type="button"
                className="cursor-pointer border-none bg-transparent p-2 focus-visible:ring-1 focus-visible:ring-components-input-border-active focus-visible:outline-hidden"
                aria-label={t('operation.delete', { ns: 'common' })}
                onClick={removeFile}
              >
                <RiDeleteBinLine className="size-4 text-text-secondary" aria-hidden="true" />
              </button>
            </div>
          </div>
        )}
      </div>
    </div>
  )
}
export default React.memo(CSVUploader)
