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|
<!-- eslint-disable vue/multi-word-component-names -->
<script>
import katex from 'katex';
import { marked } from 'marked';
import SafeHtml from '~/vue_shared/directives/safe_html';
import { sanitize } from '~/lib/dompurify';
import { hasContent, markdownConfig } from '~/lib/utils/text_utility';
import Prompt from './prompt.vue';
const renderer = new marked.Renderer();
/*
Regex to match KaTex blocks.
Supports the following:
\begin{equation}<math>\end{equation}
$$<math>$$
inline $<math>$
The matched text then goes through the KaTex renderer & then outputs the HTML
*/
const katexRegexString = `(
^\\\\begin{[a-zA-Z]+}\\s
|
^\\$\\$
|
\\s\\$(?!\\$)
)
((.|\\n)+?)
(
\\s\\\\end{[a-zA-Z]+}$
|
\\$\\$$
|
\\$
)
`
.replace(/\s/g, '')
.trim();
function deHTMLify(t) {
// get some specific characters back, that are allowed for KaTex rendering
const text = t.replace(/'/g, "'").replace(/</g, '<').replace(/>/g, '>');
return text;
}
function renderKatex(t) {
let text = t;
let numInline = 0; // number of successfull converted math formulas
if (typeof katex !== 'undefined') {
const katexString = text
.replace(/&/g, '&')
.replace(/&=&/g, '\\space=\\space') // eslint-disable-line @gitlab/require-i18n-strings
.replace(/<(\/?)em>/g, '_');
const regex = new RegExp(katexRegexString, 'gi');
const matchLocation = katexString.search(regex);
const numberOfMatches = katexString.match(regex);
if (numberOfMatches && numberOfMatches.length !== 0) {
let matches = regex.exec(katexString);
if (matchLocation > 0) {
numInline += 1;
while (matches !== null) {
try {
const renderedKatex = katex.renderToString(deHTMLify(matches[0].replace(/\$/g, '')));
text = `${text.replace(matches[0], ` ${renderedKatex}`)}`;
} catch {
numInline -= 1;
}
matches = regex.exec(katexString);
}
} else {
try {
text = katex.renderToString(deHTMLify(matches[2]));
} catch (error) {
numInline -= 1;
}
}
}
}
return [text, numInline > 0];
}
renderer.paragraph = (t) => {
const [text, inline] = renderKatex(t);
return `<p class="${inline ? 'inline-katex' : ''}">${text}</p>`;
};
renderer.listitem = (t) => {
const [text, inline] = renderKatex(t);
return `<li class="${inline ? 'inline-katex' : ''}">${text}</li>`;
};
renderer.originalImage = renderer.image;
renderer.image = function image(href, title, text) {
const attachmentHeader = `attachment:`; // eslint-disable-line @gitlab/require-i18n-strings
if (!this.attachments || !href.startsWith(attachmentHeader)) {
let relativeHref = href;
// eslint-disable-next-line @gitlab/require-i18n-strings
if (!(href.startsWith('http') || href.startsWith('data:'))) {
// These are images within the repo. This will only work if the image
// is relative to the path where the file is located
relativeHref = this.relativeRawPath + href;
}
return this.originalImage(relativeHref, title, text);
}
let img = ``;
const filename = href.substring(attachmentHeader.length);
if (hasContent(filename)) {
const attachment = this.attachments[filename];
if (attachment) {
const imageType = Object.keys(attachment)[0];
if (hasContent(imageType)) {
const data = attachment[imageType];
const inlined = `data:${imageType};base64,${data}"`; // eslint-disable-line @gitlab/require-i18n-strings
img = this.originalImage(inlined, title, text);
}
}
}
if (!hasContent(img)) {
return this.originalImage(href, title, text);
}
return sanitize(img);
};
marked.setOptions({
renderer,
});
export default {
components: {
Prompt,
},
directives: {
SafeHtml,
},
inject: ['relativeRawPath'],
props: {
cell: {
type: Object,
required: true,
},
hidePrompt: {
type: Boolean,
required: false,
default: false,
},
},
computed: {
markdown() {
renderer.attachments = this.cell.attachments;
renderer.relativeRawPath = this.relativeRawPath;
return marked(this.cell.source.join('').replace(/\\/g, '\\\\'));
},
},
markdownConfig,
};
</script>
<template>
<div class="cell text-cell">
<prompt v-if="!hidePrompt" />
<div v-safe-html:[$options.markdownConfig]="markdown" class="markdown"></div>
</div>
</template>
<style>
/*
Importing the necessary katex stylesheet from the node_module folder rather
than copying the stylesheet into `app/assets/stylesheets/vendors` for
automatic importing via `app/assets/stylesheets/application.scss`. The reason
is that the katex stylesheet depends on many fonts that are in node_module
subfolders - moving all these fonts would make updating katex difficult.
*/
@import '~katex/dist/katex.min.css';
.markdown .katex {
display: block;
text-align: center;
}
.markdown .inline-katex .katex {
display: inline;
text-align: initial;
}
</style>
|