chore(markdownit): inline taskLists plugin

The upstream version was unmaintained and removed from NPM some time ago
and no longer compatible with latest markdownit.

Taken from https://github.com/hedgedoc/hedgedoc/blob/f5736dad0f2593b44d4db687e09f3f0247ee3ce4/markdown-it-plugins/src/task-lists/index.ts

Signed-off-by: Jonas <jonas@freesources.org>

package.json

@@ -33,7 +33,6 @@
     "extends @nextcloud/browserslist-config"
   ],
   "dependencies": {
-    "@hedgedoc/markdown-it-task-lists": "^2.0.1",
     "@mdi/svg": "^7.4.47",
     "@nextcloud/auth": "^2.4.0",
     "@nextcloud/axios": "^2.5.1",

src/markdownit/details.ts

@@ -4,8 +4,8 @@
  */
 
 import type MarkdownIt from 'markdown-it'
-import type StateBlock from 'markdown-it/lib/rules_block/state_block'
-import type Token from 'markdown-it/lib/token'
+import type StateBlock from 'markdown-it/lib/rules_block/state_block.mjs'
+import type Token from 'markdown-it/lib/token.mjs'
 
 const DETAILS_START_REGEX = /^<details>\s*$/
 const DETAILS_END_REGEX = /^<\/details>\s*$/

src/markdownit/hardbreak.js

@@ -3,8 +3,8 @@
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
 
-import markdownitNewline from 'markdown-it/lib/rules_inline/newline.js'
-import markdownitEscape from 'markdown-it/lib/rules_inline/escape.js'
+import markdownitNewline from 'markdown-it/lib/rules_inline/newline.mjs'
+import markdownitEscape from 'markdown-it/lib/rules_inline/escape.mjs'
 
 /**
  * Add information about used markdown syntax to HTML hard breaks

src/markdownit/index.js

@@ -4,7 +4,7 @@
  */
 
 import MarkdownIt from 'markdown-it'
-import taskLists from '@hedgedoc/markdown-it-task-lists'
+import taskLists from './taskLists.ts'
 import markdownitMentions from '@quartzy/markdown-it-mentions'
 import underline from './underline.js'
 import splitMixedLists from './splitMixedLists.js'
@@ -15,7 +15,7 @@ import hardbreak from './hardbreak.js'
 import keepSyntax from './keepSyntax.js'
 import frontMatter from 'markdown-it-front-matter'
 import implicitFigures from 'markdown-it-image-figures'
-import { escapeHtml } from 'markdown-it/lib/common/utils.js'
+import { escapeHtml } from 'markdown-it/lib/common/utils.mjs'
 
 const markdownit = MarkdownIt('commonmark', { html: false, breaks: false })
 	.enable('strikethrough')

src/markdownit/taskLists.ts

@@ -0,0 +1,159 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+// Markdown-it plugin to render GitHub-style task lists; see
+//
+// https://github.com/blog/1375-task-lists-in-gfm-issues-pulls-comments
+// https://github.com/blog/1825-task-lists-in-all-markdown-documents
+
+import MarkdownIt from 'markdown-it'
+import StateCore from 'markdown-it/lib/rules_core/state_core.mjs'
+import Token from 'markdown-it/lib/token.mjs'
+
+interface TaskListsOptions {
+  enabled: boolean
+  label: boolean
+  lineNumber: boolean
+}
+
+const checkboxRegex = /^ *\[([\sx])] /i
+
+export default function taskLists(
+  md: MarkdownIt,
+  options: TaskListsOptions = { enabled: false, label: false, lineNumber: false }
+): void {
+  md.core.ruler.after('inline', 'task-lists', (state) => processToken(state, options))
+  md.renderer.rules.taskListItemCheckbox = (tokens) => {
+    const token = tokens[0]
+    const checkedAttribute = token.attrGet('checked') ? 'checked="" ' : ''
+    const disabledAttribute = token.attrGet('disabled') ? 'disabled="" ' : ''
+    const line = token.attrGet('line')
+    const idAttribute = `id="${token.attrGet('id')}" `
+    const dataLineAttribute = line && options.lineNumber ? `data-line="${line}" ` : ''
+
+    return `<input class="task-list-item-checkbox" type="checkbox" ${checkedAttribute}${disabledAttribute}${dataLineAttribute}${idAttribute}/>`
+  }
+
+  md.renderer.rules.taskListItemLabel_close = () => {
+    return '</label>'
+  }
+
+  md.renderer.rules.taskListItemLabel_open = (tokens: Token[]) => {
+    const token = tokens[0]
+    const id = token.attrGet('id')
+    return `<label for="${id}">`
+  }
+}
+
+function processToken(state: StateCore, options: TaskListsOptions): boolean {
+  const allTokens = state.tokens
+  for (let i = 2; i < allTokens.length; i++) {
+    if (!isTodoItem(allTokens, i)) {
+      continue
+    }
+
+    todoify(allTokens[i], options)
+    allTokens[i - 2].attrJoin('class', `task-list-item ${options.enabled ? ' enabled' : ''}`)
+
+    const parentToken = findParentToken(allTokens, i - 2)
+    if (parentToken) {
+      const classes = parentToken.attrGet('class') ?? ''
+      if (!classes.match(/(^| )contains-task-list/)) {
+        parentToken.attrJoin('class', 'contains-task-list')
+      }
+    }
+  }
+  return false
+}
+
+function findParentToken(tokens: Token[], index: number): Token | undefined {
+  const targetLevel = tokens[index].level - 1
+  for (let currentTokenIndex = index - 1; currentTokenIndex >= 0; currentTokenIndex--) {
+    if (tokens[currentTokenIndex].level === targetLevel) {
+      return tokens[currentTokenIndex]
+    }
+  }
+  return undefined
+}
+
+function isTodoItem(tokens: Token[], index: number): boolean {
+  return (
+    isInline(tokens[index]) &&
+    isParagraph(tokens[index - 1]) &&
+    isListItem(tokens[index - 2]) &&
+    startsWithTodoMarkdown(tokens[index])
+  )
+}
+
+function todoify(token: Token, options: TaskListsOptions): void {
+  if (token.children == null) {
+    return
+  }
+
+  const id = generateIdForToken(token)
+
+  token.children.splice(0, 0, createCheckboxToken(token, options.enabled, id))
+  token.children[1].content = token.children[1].content.replace(checkboxRegex, '')
+
+  if (options.label) {
+    token.children.splice(1, 0, createLabelBeginToken(id))
+    token.children.push(createLabelEndToken())
+  }
+}
+
+function generateIdForToken(token: Token): string {
+  if (token.map) {
+    return `task-item-${token.map[0]}`
+  } else {
+    return `task-item-${Math.ceil(Math.random() * (10000 * 1000) - 1000)}`
+  }
+}
+
+function createCheckboxToken(token: Token, enabled: boolean, id: string): Token {
+  const checkbox = new Token('taskListItemCheckbox', '', 0)
+  if (!enabled) {
+    checkbox.attrSet('disabled', 'true')
+  }
+  if (token.map) {
+    checkbox.attrSet('line', token.map[0].toString())
+  }
+
+  checkbox.attrSet('id', id)
+
+  const checkboxRegexResult = checkboxRegex.exec(token.content)
+  const isChecked = checkboxRegexResult?.[1].toLowerCase() === 'x'
+  if (isChecked) {
+    checkbox.attrSet('checked', 'true')
+  }
+
+  return checkbox
+}
+
+function createLabelBeginToken(id: string): Token {
+  const labelBeginToken = new Token('taskListItemLabel_open', '', 1)
+  labelBeginToken.attrSet('id', id)
+  return labelBeginToken
+}
+
+function createLabelEndToken(): Token {
+  return new Token('taskListItemLabel_close', '', -1)
+}
+
+function isInline(token: Token): boolean {
+  return token.type === 'inline'
+}
+
+function isParagraph(token: Token): boolean {
+  return token.type === 'paragraph_open'
+}
+
+function isListItem(token: Token): boolean {
+  return token.type === 'list_item_open'
+}
+
+function startsWithTodoMarkdown(token: Token): boolean {
+  return checkboxRegex.test(token.content)
+}