From 23e71e95f487fc55e7470b4b7032ae22ccd54de4 Mon Sep 17 00:00:00 2001
From: Emile Bangma <ewjbangma@hotmail.com>
Date: Thu, 19 Sep 2024 09:42:56 +0000
Subject: [PATCH] Obsidian Parsers (Arrow)

---
 quartz/plugins/parsers/obsidian/arrows.ts | 42 +++++++++++++++++++++++
 quartz/plugins/parsers/obsidian/index.ts  |  1 +
 quartz/plugins/transformers/markdown.ts   | 35 +++++++++++++++++++
 3 files changed, 78 insertions(+)

diff --git a/quartz/plugins/parsers/obsidian/arrows.ts b/quartz/plugins/parsers/obsidian/arrows.ts
index e69de29bb..0916b9a59 100644
--- a/quartz/plugins/parsers/obsidian/arrows.ts
+++ b/quartz/plugins/parsers/obsidian/arrows.ts
@@ -0,0 +1,42 @@
+import { QuartzTransformerPlugin } from "../../types"
+import { ReplaceFunction, findAndReplace as mdastFindReplace } from "mdast-util-find-and-replace"
+import { SKIP } from "unist-util-visit"
+import { Root } from "mdast"
+
+const arrowMapping: Record<string, string> = {
+  "->": "&rarr;",
+  "-->": "&rArr;",
+  "=>": "&rArr;",
+  "==>": "&rArr;",
+  "<-": "&larr;",
+  "<--": "&lArr;",
+  "<=": "&lArr;",
+  "<==": "&lArr;",
+}
+
+const arrowRegex = new RegExp(/(-{1,2}>|={1,2}>|<-{1,2}|<={1,2})/g)
+
+export const ObsidianMarkdownArrow: QuartzTransformerPlugin = () => {
+  return {
+    name: "ObsidianMarkdownArrow",
+    markdownPlugins() {
+      return [
+        (tree: Root) => {
+          const replacements: [RegExp, string | ReplaceFunction][] = []
+          replacements.push([
+            arrowRegex,
+            (value: string, ..._capture: string[]) => {
+              const maybeArrow = arrowMapping[value]
+              if (maybeArrow === undefined) return SKIP
+              return {
+                type: "html",
+                value: `<span>${maybeArrow}</span>`,
+              }
+            },
+          ])
+          mdastFindReplace(tree, replacements)
+        },
+      ]
+    },
+  }
+}
diff --git a/quartz/plugins/parsers/obsidian/index.ts b/quartz/plugins/parsers/obsidian/index.ts
index e69de29bb..100d6069b 100644
--- a/quartz/plugins/parsers/obsidian/index.ts
+++ b/quartz/plugins/parsers/obsidian/index.ts
@@ -0,0 +1 @@
+export { ObsidianMarkdownArrow } from "./arrows"
diff --git a/quartz/plugins/transformers/markdown.ts b/quartz/plugins/transformers/markdown.ts
index 18c5444f8..4d901f52b 100644
--- a/quartz/plugins/transformers/markdown.ts
+++ b/quartz/plugins/transformers/markdown.ts
@@ -35,6 +35,8 @@ import smartypants from "remark-smartypants"
 import rehypeSlug from "rehype-slug"
 import rehypeAutolinkHeadings from "rehype-autolink-headings"
 
+import { ObsidianMarkdownArrow } from "../parsers/obsidian"
+
 export interface CommonMarkOptions {
   option1: Boolean
 }
@@ -170,6 +172,39 @@ export const ObsidianFlavoredMarkdown: QuartzTransformerPlugin<Partial<ObsidianO
   const opts = { ...defaultObsidianOptions, ...userOpts }
   return {
     name: "ObsidianFlavoredMarkdown",
+    textTransform(_ctx, src) {
+      return src
+    },
+    markdownPlugins(_ctx) {
+      const plugins: PluggableList = []
+
+      plugins.push(() => {
+        return (tree: Root, file) => {
+          //const replacements: [RegExp, string | ReplaceFunction][] = []
+          //const base = pathToRoot(file.data.slug!)
+
+          if (opts.parseArrows) {
+            ObsidianMarkdownArrow()
+          }
+
+          //mdastFindReplace(tree, replacements)
+        }
+      })
+
+      return plugins
+    },
+    htmlPlugins() {
+      const plugins: PluggableList = [rehypeRaw]
+
+      plugins.push(() => {})
+
+      return plugins
+    },
+    externalResources() {
+      const js: JSResource[] = []
+
+      return { js }
+    },
   }
 }