From 00e1a4ff8a4fad39f14f5ab02ef8b6c2ec13cf7f Mon Sep 17 00:00:00 2001
From: Jeff Wu <wuthefwasthat@gmail.com>
Date: Wed, 22 Mar 2017 21:46:27 -0700
Subject: [PATCH] fixes to katex

- report errors
- non-greedy match
- handle inner newline
- handle surrounding punctuation
---
 package.json                |  4 ++--
 src/plugins/latex/index.tsx | 31 ++++++++++++++-----------------
 typings/katex.d.ts          |  3 ---
 typings/react-katex.d.ts    |  4 ----
 4 files changed, 16 insertions(+), 26 deletions(-)
 delete mode 100644 typings/katex.d.ts
 delete mode 100644 typings/react-katex.d.ts

diff --git a/package.json b/package.json
index b1f1029f..cd4adf17 100644
--- a/package.json
+++ b/package.json
@@ -17,6 +17,7 @@
   "dependencies": {
     "@types/immutable": "^3.8.4",
     "@types/jquery": "^2.0.34",
+    "@types/katex": "^0.5.0",
     "@types/lodash": "^4.14.36",
     "@types/react": "^0.14.36",
     "@types/react-dom": "^0.14.18",
@@ -27,8 +28,7 @@
     "katex": "^0.7.1",
     "lodash": "^4.15.0",
     "react": "^15.3.1",
-    "react-dom": "^15.3.1",
-    "react-katex": "^1.1.0"
+    "react-dom": "^15.3.1"
   },
   "devDependencies": {
     "@types/mocha": "^2.2.32",
diff --git a/src/plugins/latex/index.tsx b/src/plugins/latex/index.tsx
index 8cfcf3fd..12e0d4c3 100644
--- a/src/plugins/latex/index.tsx
+++ b/src/plugins/latex/index.tsx
@@ -1,13 +1,15 @@
 import React from 'react'; // tslint:disable-line no-unused-variable
-///<reference path="typings/katex.d.ts"/>
 import katex from 'katex';
-///<reference path="typings/react-katex.d.ts"/>
-import { InlineMath, BlockMath } from 'react-katex';
 import 'katex/dist/katex.min.css';
 
 import { Token, RegexTokenizerSplitter, EmitFn } from '../../assets/js/utils/token_scanner';
 import { registerPlugin } from '../../assets/js/plugins';
 
+// ignore the group, allow whitespace, beginning of line, or open paren
+const latexPreRegex = '(?:\\s|^|\\()';
+// ignore the group, allow whitespace, end of line, punctuation, or close paren
+const latexPostRegex = '(?:\\s|$|\\.|,|!|\\?|\\))';
+
 registerPlugin<void>(
   {
     name: 'LaTeX',
@@ -15,12 +17,13 @@ registerPlugin<void>(
     description: `
       Lets you inline LaTeX between $ delimiters,
       or add block LaTeX between $$ delimiters.
+      Limited to what KaTeX supports.
     `,
   },
   function(api) {
     api.registerHook('session', 'renderLineTokenHook', (tokenizer) => {
       return tokenizer.chain(RegexTokenizerSplitter<React.ReactNode>(
-        new RegExp('(?:\\s|^)(\\$\\$.+\\$\\$)(?:\\s|$)'),
+        new RegExp(latexPreRegex + '(\\$\\$(\\n|.)+?\\$\\$)' + latexPostRegex),
         (token: Token, emitToken: EmitFn<Token>, emit: EmitFn<React.ReactNode>) => {
           for (let i = 0; i < token.info.length; i++) {
             if (token.info[i].cursor) {
@@ -31,18 +34,15 @@ registerPlugin<void>(
             }
           }
           try {
-            katex.__parse(token.text.slice(2, -2));
-            emit(
-              <BlockMath key={`latex-${token.index}`}>
-                {token.text.slice(2, -2)}
-              </BlockMath>
-            );
+            const html = katex.renderToString(token.text.slice(2, -2), { displayMode: true });
+            emit(<div key={`latex-${token.index}`} dangerouslySetInnerHTML={{__html: html}}/>);
           } catch (e) {
+            api.session.showMessage(e.message, { text_class: 'error' });
             emitToken(token);
           }
         }
       )).chain(RegexTokenizerSplitter<React.ReactNode>(
-        new RegExp('(?:\\s|^)(\\$.+\\$)(?:\\s|$)'),
+        new RegExp(latexPreRegex + '(\\$(\\n|.)+?\\$)' + latexPostRegex),
         (token: Token, emitToken: EmitFn<Token>, emit: EmitFn<React.ReactNode>) => {
           for (let i = 0; i < token.info.length; i++) {
             if (token.info[i].cursor) {
@@ -53,13 +53,10 @@ registerPlugin<void>(
             }
           }
           try {
-            katex.__parse(token.text.slice(-1, 1));
-            emit(
-              <InlineMath key={`latex-${token.index}`}>
-                {token.text.slice(1, -1)}
-              </InlineMath>
-            );
+            const html = katex.renderToString(token.text.slice(1, -1), { displayMode: false });
+            emit(<span key={`latex-${token.index}`} dangerouslySetInnerHTML={{__html: html}}/>);
           } catch (e) {
+            api.session.showMessage(e.message, { text_class: 'error' });
             emitToken(token);
           }
         }
diff --git a/typings/katex.d.ts b/typings/katex.d.ts
deleted file mode 100644
index 2fb6c72a..00000000
--- a/typings/katex.d.ts
+++ /dev/null
@@ -1,3 +0,0 @@
-declare module 'katex' {
-  export const __parse: any;
-}
diff --git a/typings/react-katex.d.ts b/typings/react-katex.d.ts
deleted file mode 100644
index 35bdd349..00000000
--- a/typings/react-katex.d.ts
+++ /dev/null
@@ -1,4 +0,0 @@
-declare module 'react-katex' {
-  export const InlineMath: any;
-  export const BlockMath: any;
-}