import Image, { AuthenticatedImg } from '@/components/image';
import SvgIcon from '@/components/svg-icon';
import { MarkdownRemarkPlugins } from '@/constants/markdown-remark-plugins';
import { IReference, IReferenceChunk } from '@/interfaces/database/chat';
import { citationMarkerReg } from '@/utils/citation-utils';
import { getExtension } from '@/utils/document-util';
import { getDirAttribute } from '@/utils/text-direction';
import DOMPurify from 'dompurify';
import { useCallback, useEffect, useMemo } from 'react';
import Markdown from 'react-markdown';
import SyntaxHighlighter from 'react-syntax-highlighter';
import rehypeKatex from 'rehype-katex';
import rehypeRaw from 'rehype-raw';
import { visitParents } from 'unist-util-visit-parents';

import { useTranslation } from 'react-i18next';

import 'katex/dist/katex.min.css'; // `rehype-katex` does not import the CSS for you

import { useFetchDocumentThumbnailsByIds } from '@/hooks/use-document-request';
import { useLoadingPause } from '@/hooks/use-loading-pause';
import {
  currentReg,
  parseCitationIndex,
  preprocessLaTeX,
  replaceRetrievingToSection,
  replaceTextByOldReg,
  replaceThinkToSection,
} from '@/utils/chat';
import classNames from 'classnames';
import { omit } from 'lodash';
import { pipe } from 'lodash/fp';
import reactStringReplace from 'react-string-replace';
import { LoadingDots } from '../loading-dots';
import { Button } from '../ui/button';
import {
  HoverCard,
  HoverCardContent,
  HoverCardTrigger,
} from '../ui/hover-card';
import styles from './index.module.less';

const getChunkIndex = (match: string) => parseCitationIndex(match);

const formatMetadataValue = (value: unknown) => {
  if (Array.isArray(value)) return value.join(', ');
  if (value === null || value === undefined) return '';
  if (typeof value === 'object') return JSON.stringify(value);
  return String(value);
};

// TODO: The display of the table is inconsistent with the display previously placed in the MessageItem.
const MarkdownContent = ({
  reference,
  clickDocumentButton,
  content,
  loading,
}: {
  content: string;
  loading: boolean;
  reference: IReference;
  clickDocumentButton?: (documentId: string, chunk: IReferenceChunk) => void;
}) => {
  const { t } = useTranslation();
  const { setDocumentIds, data: fileThumbnails } =
    useFetchDocumentThumbnailsByIds();
  const contentWithCursor = useMemo(() => {
    let text = DOMPurify.sanitize(content, {
      ADD_TAGS: ['think', 'section', 'details', 'summary', 'retrieving'],
      ADD_ATTR: ['class'],
    });

    // let text = content;
    if (text === '') {
      text = t('chat.searching');
    }
    const nextText = replaceTextByOldReg(text);
    return pipe(
      replaceThinkToSection,
      replaceRetrievingToSection,
      preprocessLaTeX,
    )(nextText);
  }, [content, t]);

  useEffect(() => {
    const docAggs = reference?.doc_aggs;
    setDocumentIds(Array.isArray(docAggs) ? docAggs.map((x) => x.doc_id) : []);
  }, [reference, setDocumentIds]);

  const handleDocumentButtonClick = useCallback(
    (
      documentId: string,
      chunk: IReferenceChunk,
      isPdf: boolean,
      documentUrl?: string,
    ) =>
      () => {
        if (!isPdf) {
          if (!documentUrl) {
            return;
          }
          window.open(documentUrl, '_blank');
        } else {
          clickDocumentButton?.(documentId, chunk);
        }
      },
    [clickDocumentButton],
  );

  const rehypeWrapReference = () => {
    return function wrapTextTransform(tree: any) {
      visitParents(tree, 'text', (node, ancestors) => {
        const latestAncestor = ancestors.at(-1);
        if (
          latestAncestor.tagName !== 'custom-typography' &&
          latestAncestor.tagName !== 'code'
        ) {
          node.type = 'element';
          node.tagName = 'custom-typography';
          node.properties = {};
          node.children = [{ type: 'text', value: node.value }];
        }
      });
    };
  };

  const getReferenceInfo = useCallback(
    (chunkIndex: number) => {
      const chunks = reference?.chunks ?? [];
      const chunkItem = chunks[chunkIndex];
      const document = reference?.doc_aggs?.find(
        (x) => x?.doc_id === chunkItem?.document_id,
      );
      const documentId = document?.doc_id;
      const documentUrl = document?.url;
      const fileThumbnail = documentId ? fileThumbnails[documentId] : '';
      const fileExtension = documentId ? getExtension(document?.doc_name) : '';
      const imageId = chunkItem?.image_id;

      return {
        documentUrl,
        fileThumbnail,
        fileExtension,
        imageId,
        chunkItem,
        documentId,
        document,
      };
    },
    [fileThumbnails, reference],
  );

  const getPopoverContent = useCallback(
    (chunkIndex: number) => {
      const {
        documentUrl,
        fileThumbnail,
        fileExtension,
        imageId,
        chunkItem,
        documentId,
        document,
      } = getReferenceInfo(chunkIndex);

      return (
        <div key={chunkItem?.id} className="flex gap-2">
          {imageId && (
            <HoverCard>
              <HoverCardTrigger>
                <Image
                  id={imageId}
                  className={styles.referenceChunkImage}
                ></Image>
              </HoverCardTrigger>
              <HoverCardContent>
                <Image
                  id={imageId}
                  className={styles.referenceImagePreview}
                ></Image>
              </HoverCardContent>
            </HoverCard>
          )}
          <div className={'space-y-2 max-w-[40vw]'}>
            <div
              dangerouslySetInnerHTML={{
                __html: DOMPurify.sanitize(chunkItem?.content ?? ''),
              }}
              className={classNames(styles.chunkContentText)}
              dir="auto"
            ></div>
            {chunkItem?.document_metadata &&
              Object.keys(chunkItem.document_metadata).length > 0 && (
                <section className="space-y-1 border border-border-default rounded p-2">
                  {Object.entries(chunkItem.document_metadata).map(
                    ([key, value]) => (
                      <div key={key} className="text-xs">
                        <span className="text-text-secondary">{key}:</span>{' '}
                        <span className="text-text-primary">
                          {formatMetadataValue(value)}
                        </span>
                      </div>
                    ),
                  )}
                </section>
              )}
            {documentId && (
              <section className="flex gap-1">
                {fileThumbnail ? (
                  <AuthenticatedImg
                    src={fileThumbnail}
                    alt=""
                    className={styles.fileThumbnail}
                  />
                ) : (
                  <SvgIcon
                    name={`file-icon/${fileExtension}`}
                    width={24}
                  ></SvgIcon>
                )}
                <Button
                  variant="link"
                  className={'text-wrap p-0 flex-1 h-auto'}
                  onClick={handleDocumentButtonClick(
                    documentId,
                    chunkItem,
                    fileExtension === 'pdf',
                    documentUrl,
                  )}
                >
                  {document?.doc_name}
                </Button>
              </section>
            )}
          </div>
        </div>
      );
    },
    [getReferenceInfo, handleDocumentButtonClick],
  );

  const renderReference = useCallback(
    (text: string) => {
      const replacedText = reactStringReplace(text, currentReg, (match, i) => {
        const chunkIndex = getChunkIndex(match);

        return (
          <HoverCard key={i}>
            <HoverCardTrigger>
              <bdi className="text-text-secondary bg-bg-card rounded-2xl px-1 mx-1 text-nowrap inline-block">
                Fig. {chunkIndex + 1}
              </bdi>
            </HoverCardTrigger>
            <HoverCardContent className="max-w-3xl">
              {getPopoverContent(chunkIndex)}
            </HoverCardContent>
          </HoverCard>
        );
      });

      return replacedText;
    },
    [getPopoverContent],
  );

  const dir = getDirAttribute(content.replace(citationMarkerReg, ''));
  const showLoadingDots = useLoadingPause(loading, content);

  return (
    <div dir={dir} className={styles.markdownContentWrapper}>
      <Markdown
        rehypePlugins={[rehypeRaw, rehypeWrapReference, rehypeKatex]}
        remarkPlugins={MarkdownRemarkPlugins}
        components={
          {
            p: ({ children, ...props }: any) => <p {...props}>{children}</p>,
            'custom-typography': ({ children }: { children: string }) =>
              renderReference(children),
            code(props: any) {
              const { children, className, ...rest } = props;
              const restProps = omit(rest, 'node');
              const match = /language-(\w+)/.exec(className || '');
              return match ? (
                <SyntaxHighlighter
                  {...restProps}
                  PreTag="div"
                  language={match[1]}
                  wrapLongLines
                >
                  {String(children).replace(/\n$/, '')}
                </SyntaxHighlighter>
              ) : (
                <code
                  {...restProps}
                  className={classNames(className, 'text-wrap')}
                >
                  {children}
                </code>
              );
            },
          } as any
        }
      >
        {contentWithCursor}
      </Markdown>
      {showLoadingDots && (
        <LoadingDots className="ml-1 inline-block text-text-secondary" />
      )}
    </div>
  );
};

export default MarkdownContent;
