From 5baa7e3351de022e58d934140e297639f7814cc6 Mon Sep 17 00:00:00 2001
From: Tilman Vatteroth <git@tilmanvatteroth.de>
Date: Sat, 5 Nov 2022 18:07:49 +0100
Subject: [PATCH] fix: Adjust mermaid chart to new types and use useAsync

Signed-off-by: Tilman Vatteroth <git@tilmanvatteroth.de>
---
 package.json                                  |  1 -
 .../mermaid/mermaid-chart.tsx                 | 88 ++++++++-----------
 yarn.lock                                     |  8 --
 3 files changed, 36 insertions(+), 61 deletions(-)

diff --git a/package.json b/package.json
index 0bac3cfac..b58a1b1df 100644
--- a/package.json
+++ b/package.json
@@ -140,7 +140,6 @@
     "@types/markdown-it": "12.2.3",
     "@types/markdown-it-container": "2.0.5",
     "@types/markdown-it-plantuml": "1.4.1",
-    "@types/mermaid": "9.1.0",
     "@types/node": "18.11.9",
     "@types/react": "18.0.25",
     "@types/react-dom": "18.0.8",
diff --git a/src/extensions/extra-integrations/mermaid/mermaid-chart.tsx b/src/extensions/extra-integrations/mermaid/mermaid-chart.tsx
index b1f16ce91..909d860c7 100644
--- a/src/extensions/extra-integrations/mermaid/mermaid-chart.tsx
+++ b/src/extensions/extra-integrations/mermaid/mermaid-chart.tsx
@@ -4,7 +4,7 @@
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 
-import React, { Fragment, useCallback, useEffect, useRef, useState } from 'react'
+import React, { Fragment, useRef } from 'react'
 import { Alert } from 'react-bootstrap'
 import { useTranslation } from 'react-i18next'
 import styles from './mermaid.module.scss'
@@ -12,15 +12,21 @@ import type { CodeProps } from '../../../components/markdown-renderer/replace-co
 import { cypressId } from '../../../utils/cypress-attribute'
 import { ShowIf } from '../../../components/common/show-if/show-if'
 import { Logger } from '../../../utils/logger'
+import { useAsync } from 'react-use'
 
 const log = new Logger('MermaidChart')
 
-interface MermaidParseError {
-  str: string
-}
-
 let mermaidInitialized = false
 
+const loadMermaid = async (): Promise<typeof import('mermaid')> => {
+  try {
+    return import(/* webpackChunkName: "mermaid" */ 'mermaid')
+  } catch (error) {
+    log.error('Error while loading mermaid', error)
+    throw new Error('Error while loading mermaid')
+  }
+}
+
 /**
  * Renders a mermaid diagram.
  *
@@ -29,61 +35,39 @@ let mermaidInitialized = false
  */
 export const MermaidChart: React.FC<CodeProps> = ({ code }) => {
   const diagramContainer = useRef<HTMLDivElement>(null)
-  const [error, setError] = useState<string>()
   const { t } = useTranslation()
-
-  useEffect(() => {
-    if (!mermaidInitialized) {
-      import(/* webpackChunkName: "mermaid" */ 'mermaid')
-        .then((mermaid) => {
-          mermaid.default.initialize({ startOnLoad: false })
-          mermaidInitialized = true
-        })
-        .catch((error: Error) => {
-          log.error('Error while loading mermaid', error)
-        })
-    }
-  }, [])
-
-  const showError = useCallback(
-    (error: string) => {
-      setError(error)
-      log.error(error)
-      if (!diagramContainer.current) {
-        return
-      }
-      diagramContainer.current.querySelectorAll('svg').forEach((child) => child.remove())
-    },
-    [setError]
-  )
-
-  useEffect(() => {
+  const { error } = useAsync(async () => {
     if (!diagramContainer.current) {
       return
     }
-    import(/* webpackChunkName: "mermaid" */ 'mermaid')
-      .then((mermaid) => {
-        try {
-          if (!diagramContainer.current) {
-            return
-          }
-          mermaid.default.parse(code)
-          delete diagramContainer.current.dataset.processed
-          diagramContainer.current.textContent = code
-          mermaid.default.init(diagramContainer.current)
-          setError(undefined)
-        } catch (error) {
-          const message = (error as MermaidParseError).str
-          showError(message || t('renderer.mermaid.unknownError'))
-        }
-      })
-      .catch(() => showError('Error while loading mermaid'))
-  }, [code, showError, t])
+
+    const mermaid = await loadMermaid()
+
+    if (!mermaidInitialized) {
+      mermaid.default.initialize({ startOnLoad: false })
+      mermaidInitialized = true
+    }
+
+    try {
+      if (!diagramContainer.current) {
+        return
+      }
+      mermaid.default.parse(code)
+      delete diagramContainer.current.dataset.processed
+      diagramContainer.current.textContent = code
+      await mermaid.default.init(undefined, diagramContainer.current)
+    } catch (error) {
+      const message = (error as Error).message
+      log.error(error)
+      diagramContainer.current?.querySelectorAll('svg').forEach((child) => child.remove())
+      throw new Error(message || t('renderer.mermaid.unknownError'))
+    }
+  }, [code, t])
 
   return (
     <Fragment>
       <ShowIf condition={!!error}>
-        <Alert variant={'warning'}>{error}</Alert>
+        <Alert variant={'warning'}>{error?.message}</Alert>
       </ShowIf>
       <div
         {...cypressId('mermaid-frame')}
diff --git a/yarn.lock b/yarn.lock
index 16adf3ddc..fc29eaec2 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1964,7 +1964,6 @@ __metadata:
     "@types/markdown-it": 12.2.3
     "@types/markdown-it-container": 2.0.5
     "@types/markdown-it-plantuml": 1.4.1
-    "@types/mermaid": 9.1.0
     "@types/node": 18.11.9
     "@types/react": 18.0.25
     "@types/react-dom": 18.0.8
@@ -3483,13 +3482,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@types/mermaid@npm:9.1.0":
-  version: 9.1.0
-  resolution: "@types/mermaid@npm:9.1.0"
-  checksum: ea3756826c89c85efd4e182c6ef025ea24a20ee70dc168673390b1125f158f57ae231f36cb2c700ef0ea6e9c322551963404759f8d019e0e48fb7cb5d6da1f96
-  languageName: node
-  linkType: hard
-
 "@types/node@npm:*":
   version: 18.11.4
   resolution: "@types/node@npm:18.11.4"