From 904d33e895bccae5079b2e00f038e4d3729249f6 Mon Sep 17 00:00:00 2001
From: Felix Ableitner <me@nutomic.com>
Date: Wed, 16 Feb 2022 12:49:00 +0100
Subject: [PATCH] wip: support custom themes

---
 src/server/index.tsx                | 61 +++++++++++++++++++++++++++++
 src/shared/components/app/theme.tsx |  6 +--
 src/shared/utils.ts                 | 35 +++++++++--------
 3 files changed, 83 insertions(+), 19 deletions(-)

diff --git a/src/server/index.tsx b/src/server/index.tsx
index 82d0379b..f46ab157 100644
--- a/src/server/index.tsx
+++ b/src/server/index.tsx
@@ -1,4 +1,5 @@
 import express from "express";
+import fs from "fs";
 import { IncomingHttpHeaders } from "http";
 import { Helmet } from "inferno-helmet";
 import { matchPath, StaticRouter } from "inferno-router";
@@ -23,6 +24,8 @@ const server = express();
 const [hostname, port] = process.env["LEMMY_UI_HOST"]
   ? process.env["LEMMY_UI_HOST"].split(":")
   : ["0.0.0.0", "1234"];
+const extraThemesFolder =
+  process.env["LEMMY_UI_EXTRA_THEMES_FOLDER"] || "./extra_themes";
 
 server.use(express.json());
 server.use(express.urlencoded({ extended: false }));
@@ -46,6 +49,64 @@ server.get("/robots.txt", async (_req, res) => {
   res.send(robotstxt);
 });
 
+server.get("/css/themes-list", async (req, res) => {
+  const builtinThemes = [
+    "litera",
+    "materia",
+    "minty",
+    "solar",
+    "united",
+    "cyborg",
+    "darkly",
+    "journal",
+    "sketchy",
+    "vaporwave",
+    "vaporwave-dark",
+    "i386",
+    "litely",
+    "nord",
+  ];
+  fs.readdir(extraThemesFolder, function (err, data) {
+    data = data
+      .filter(d => d.endsWith(".min.css"))
+      .map(d => d.replace(".min.css", ""));
+    data = builtinThemes.concat(data);
+    // use set to remove duplicate values
+    data = Array.from(new Set(data));
+    res.send(data);
+  });
+});
+
+server.get("/css/themes/:name", async (req, res) => {
+  const theme = req.params.name;
+  if (!theme.endsWith(".css")) {
+    res.send("Theme must be a css file");
+  }
+
+  // try extra themes first
+  fs.readFile(`${extraThemesFolder}/${theme}`, "utf8", function (err, data) {
+    if (err) {
+      // if no match found, fallback to builtin themes
+      fs.readFile(
+        `./dist/assets/css/themes/${theme}`,
+        "utf8",
+        function (err, data) {
+          if (err) {
+            const message = `No theme found for name ${theme}`;
+            res.send(message);
+            console.error(message);
+            return;
+          }
+          res.send(data);
+          return;
+        }
+      );
+      return;
+    }
+    res.send(data);
+  });
+});
+
 // server.use(cookieParser());
 server.get("/*", async (req, res) => {
   try {
diff --git a/src/shared/components/app/theme.tsx b/src/shared/components/app/theme.tsx
index bf5289b1..28890a26 100644
--- a/src/shared/components/app/theme.tsx
+++ b/src/shared/components/app/theme.tsx
@@ -17,21 +17,21 @@ export class Theme extends Component<Props> {
           <link
             rel="stylesheet"
             type="text/css"
-            href={`/static/assets/css/themes/${user.local_user_view.local_user.theme}.min.css`}
+            href={`css/themes/${user.local_user_view.local_user.theme}.min.css`}
           />
         ) : (
           [
             <link
               rel="stylesheet"
               type="text/css"
-              href="/static/assets/css/themes/litely.min.css"
+              href="css/themes/litely.min.css"
               id="default-light"
               media="(prefers-color-scheme: light)"
             />,
             <link
               rel="stylesheet"
               type="text/css"
-              href="/static/assets/css/themes/darkly.min.css"
+              href="css/themes/darkly.min.css"
               id="default-dark"
               media="(prefers-color-scheme: no-preference), (prefers-color-scheme: dark)"
             />,
diff --git a/src/shared/utils.ts b/src/shared/utils.ts
index 6eb0e116..d0ff224d 100644
--- a/src/shared/utils.ts
+++ b/src/shared/utils.ts
@@ -166,22 +166,25 @@ export const languages = [
   { code: "lt" },
 ];
 
-export const themes = [
-  "litera",
-  "materia",
-  "minty",
-  "solar",
-  "united",
-  "cyborg",
-  "darkly",
-  "journal",
-  "sketchy",
-  "vaporwave",
-  "vaporwave-dark",
-  "i386",
-  "litely",
-  "nord",
-];
+export function themes() {
+  const builtinThemes = [
+    "litera",
+    "materia",
+    "minty",
+    "solar",
+    "united",
+    "cyborg",
+    "darkly",
+    "journal",
+    "sketchy",
+    "vaporwave",
+    "vaporwave-dark",
+    "i386",
+    "litely",
+    "nord",
+  ];
+  return builtinThemes;
+}
 
 const DEFAULT_ALPHABET =
   "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";