import growiDirective from '@growi/remark-growi-directive';
import type { Schema as SanitizeOption } from 'hast-util-sanitize';
import katex from 'rehype-katex';
import raw from 'rehype-raw';
import sanitize from 'rehype-sanitize';
import slug from 'rehype-slug';
import breaks from 'remark-breaks';
import remarkDirective from 'remark-directive';
import remarkFrontmatter from 'remark-frontmatter';
import gfm from 'remark-gfm';
import math from 'remark-math';
import deepmerge from 'ts-deepmerge';
import type { Pluggable, PluginTuple } from 'unified';


import { CodeBlock } from '~/components/ReactMarkdownComponents/CodeBlock';
import { NextLink } from '~/components/ReactMarkdownComponents/NextLink';
import type { RendererOptions } from '~/interfaces/renderer-options';
import { RehypeSanitizeType } from '~/interfaces/services/rehype-sanitize';
import type { RendererConfig } from '~/interfaces/services/renderer';
import loggerFactory from '~/utils/logger';

import { tagNames as recommendedTagNames, attributes as recommendedAttributes } from './recommended-whitelist';
import * as addClass from './rehype-plugins/add-class';
import { relativeLinks } from './rehype-plugins/relative-links';
import { relativeLinksByPukiwikiLikeLinker } from './rehype-plugins/relative-links-by-pukiwiki-like-linker';
import * as codeBlock from './remark-plugins/codeblock';
import * as echoDirective from './remark-plugins/echo-directive';
import * as emoji from './remark-plugins/emoji';
import { pukiwikiLikeLinker } from './remark-plugins/pukiwiki-like-linker';
import * as xsvToTable from './remark-plugins/xsv-to-table';


// import EasyGrid from './PreProcessor/EasyGrid';


// eslint-disable-next-line @typescript-eslint/no-unused-vars
const logger = loggerFactory('growi:services:renderer');


type SanitizePlugin = PluginTuple<[SanitizeOption]>;

let currentInitializedSanitizeType: RehypeSanitizeType = RehypeSanitizeType.RECOMMENDED;
let commonSanitizeOption: SanitizeOption;
export const getCommonSanitizeOption = (config:RendererConfig): SanitizeOption => {
  if (commonSanitizeOption == null || config.sanitizeType !== currentInitializedSanitizeType) {
    // initialize
    commonSanitizeOption = deepmerge(
      {
        tagNames: config.sanitizeType === RehypeSanitizeType.RECOMMENDED
          ? recommendedTagNames
          : config.customTagWhitelist ?? recommendedTagNames,
        attributes: config.sanitizeType === RehypeSanitizeType.RECOMMENDED
          ? recommendedAttributes
          : config.customAttrWhitelist ?? recommendedAttributes,
        clobberPrefix: '', // remove clobber prefix
      },
      codeBlock.sanitizeOption,
    );

    currentInitializedSanitizeType = config.sanitizeType;
  }

  return commonSanitizeOption;
};


const isSanitizePlugin = (pluggable: Pluggable): pluggable is SanitizePlugin => {
  if (!Array.isArray(pluggable) || pluggable.length < 2) {
    return false;
  }
  const sanitizeOption = pluggable[1];
  return 'tagNames' in sanitizeOption && 'attributes' in sanitizeOption;
};

const hasSanitizePlugin = (options: RendererOptions, shouldBeTheLastItem: boolean): boolean => {
  const { rehypePlugins } = options;
  if (rehypePlugins == null || rehypePlugins.length === 0) {
    return false;
  }

  return shouldBeTheLastItem
    ? isSanitizePlugin(rehypePlugins.slice(-1)[0]) // evaluate the last one
    : rehypePlugins.some(rehypePlugin => isSanitizePlugin(rehypePlugin));
};

export const verifySanitizePlugin = (options: RendererOptions, shouldBeTheLastItem = true): void => {
  if (hasSanitizePlugin(options, shouldBeTheLastItem)) {
    return;
  }

  throw new Error('The specified options does not have sanitize plugin in \'rehypePlugins\'');
};

export const generateCommonOptions = (pagePath: string|undefined): RendererOptions => {
  return {
    remarkPlugins: [
      gfm,
      emoji.remarkPlugin,
      pukiwikiLikeLinker,
      growiDirective,
      remarkDirective,
      echoDirective.remarkPlugin,
      remarkFrontmatter,
      codeBlock.remarkPlugin,
    ],
    remarkRehypeOptions: {
      clobberPrefix: '', // remove clobber prefix
      allowDangerousHtml: true,
    },
    rehypePlugins: [
      [relativeLinksByPukiwikiLikeLinker, { pagePath }],
      [relativeLinks, { pagePath }],
      raw,
      [addClass.rehypePlugin, {
        table: 'table table-bordered',
      }],
    ],
    components: {
      a: NextLink,
      code: CodeBlock,
    },
  };
};


export const generateSSRViewOptions = (
    config: RendererConfig,
    pagePath: string,
): RendererOptions => {

  const options = generateCommonOptions(pagePath);

  const { remarkPlugins, rehypePlugins } = options;

  // add remark plugins
  remarkPlugins.push(
    math,
    xsvToTable.remarkPlugin,
  );

  const isEnabledLinebreaks = config.isEnabledLinebreaks;

  if (isEnabledLinebreaks) {
    remarkPlugins.push(breaks);
  }

  const rehypeSanitizePlugin: Pluggable | (() => void) = config.isEnabledXssPrevention
    ? [sanitize, getCommonSanitizeOption(config)]
    : () => {};

  // add rehype plugins
  rehypePlugins.push(
    slug,
    rehypeSanitizePlugin,
    katex,
  );

  // add components
  // if (components != null) {
  // }

  if (config.isEnabledXssPrevention) {
    verifySanitizePlugin(options, false);
  }
  return options;
};