refac: katex

src/lib/utils/index.ts

@@ -25,7 +25,8 @@ const convertLatexToSingleLine = (content) => {
 
 export const sanitizeResponseContent = (content: string) => {
 	// replace single backslash with double backslash
-	content = content.replace(/\\/g, '\\\\');
+	content = content.replace(/\\\\/g, '\\\\\\\\');
+
 	content = convertLatexToSingleLine(content);
 
 	// First, temporarily replace valid <video> tags with a placeholder
@@ -87,7 +88,7 @@ export const replaceTokens = (content, char, user) => {
 };
 
 export const revertSanitizedResponseContent = (content: string) => {
-	return content.replaceAll('&lt;', '<').replaceAll('&gt;', '>');
+	return content.replaceAll('&lt;', '<').replaceAll('&gt;', '>').replaceAll('\\\\', '\\');
 };
 
 export function unescapeHtml(html: string) {

src/lib/utils/katex-extension.ts

@@ -0,0 +1,80 @@
+import katex from 'katex';
+
+const inlineRule = /^(\${1,2})(?!\$)((?:\\.|[^\\\n])*?(?:\\.|[^\\\n\$]))\1(?=[\s?!\.,:？！。，：]|$)/;
+const inlineRuleNonStandard = /^(\${1,2})(?!\$)((?:\\.|[^\\\n])*?(?:\\.|[^\\\n\$]))\1/; // Non-standard, even if there are no spaces before and after $ or $$, try to parse
+
+const blockRule = /^(\${1,2})\n((?:\\[^]|[^\\])+?)\n\1(?:\n|$)/;
+
+export default function(options = {}) {
+  return {
+    extensions: [
+      inlineKatex(options, createRenderer(options, false)),
+      blockKatex(options, createRenderer(options, true)),
+    ],
+  };
+}
+
+function createRenderer(options, newlineAfter) {
+  return (token) => katex.renderToString(token.text, { ...options, displayMode: token.displayMode }) + (newlineAfter ? '\n' : '');
+}
+
+function inlineKatex(options, renderer) {
+  const nonStandard = options && options.nonStandard;
+  const ruleReg = nonStandard ? inlineRuleNonStandard : inlineRule;
+  return {
+    name: 'inlineKatex',
+    level: 'inline',
+    start(src) {
+      let index;
+      let indexSrc = src;
+
+      while (indexSrc) {
+        index = indexSrc.indexOf('$');
+        if (index === -1) {
+          return;
+        }
+        const f = nonStandard ? index > -1 : index === 0 || indexSrc.charAt(index - 1) === ' ';
+        if (f) {
+          const possibleKatex = indexSrc.substring(index);
+
+          if (possibleKatex.match(ruleReg)) {
+            return index;
+          }
+        }
+
+        indexSrc = indexSrc.substring(index + 1).replace(/^\$+/, '');
+      }
+    },
+    tokenizer(src, tokens) {
+      const match = src.match(ruleReg);
+      if (match) {
+        return {
+          type: 'inlineKatex',
+          raw: match[0],
+          text: match[2].trim(),
+          displayMode: match[1].length === 2,
+        };
+      }
+    },
+    renderer,
+  };
+}
+
+function blockKatex(options, renderer) {
+  return {
+    name: 'blockKatex',
+    level: 'block',
+    tokenizer(src, tokens) {
+      const match = src.match(blockRule);
+      if (match) {
+        return {
+          type: 'blockKatex',
+          raw: match[0],
+          text: match[2].trim(),
+          displayMode: match[1].length === 2,
+        };
+      }
+    },
+    renderer,
+  };
+}