feat: add chinese font support for pandoc

compose.yaml

@@ -5,6 +5,7 @@ services:
       # dockerfile: Debian.Dockerfile
     volumes:
       - ./data:/app/data
+      # - /usr/share/fonts/truetype/chinese:/usr/share/fonts/truetype/chinese:ro # mount Chinese fonts from host (optional)
     environment: # Defaults are listed below. All are optional.
       - ACCOUNT_REGISTRATION=true # true or false, doesn't matter for the first account (e.g. keep this to false if you only want one account)
       - JWT_SECRET=aLongAndSecretStringUsedToSignTheJSONWebToken1234 # will use randomUUID() by default
@@ -16,5 +17,8 @@ services:
       # - HIDE_HISTORY=true # hides the history tab in the web interface, defaults to false
       - TZ=Europe/Stockholm # set your timezone, defaults to UTC
       # - UNAUTHENTICATED_USER_SHARING=true # for use with ALLOW_UNAUTHENTICATED=true to share history with all unauthenticated users / devices
+      # - PANDOC_ENABLE_CHINESE_FONT=true # enable Chinese font support for Pandoc PDF/LaTeX conversion
+      # - PANDOC_CHINESE_FONT_PATH=/usr/share/fonts/truetype/chinese # path to Chinese font directory on host
+      # - PANDOC_CHINESE_FONT_FAMILY=NotoSansCJK # Chinese font family name
     ports:
       - 3000:3000

src/converters/pandoc.ts

@@ -1,5 +1,10 @@
 import { execFile as execFileOriginal } from "node:child_process";
 import { ExecFileFn } from "./types";
+import { 
+  PANDOC_ENABLE_CHINESE_FONT, 
+  PANDOC_CHINESE_FONT_PATH, 
+  PANDOC_CHINESE_FONT_FAMILY 
+} from "../helpers/env";
 
 export const properties = {
   from: {
@@ -136,6 +141,24 @@ export function convert(
 
   if (xelatex.includes(convertTo)) {
     args.push("--pdf-engine=xelatex");
+    
+    // Add Chinese font support if enabled
+    if (PANDOC_ENABLE_CHINESE_FONT) {
+      // Create a custom LaTeX template for Chinese font support
+      const chineseFontArgs = [
+        "-V", `mainfont=${PANDOC_CHINESE_FONT_FAMILY}`,
+        "-V", "CJKmainfont=" + PANDOC_CHINESE_FONT_FAMILY,
+        "--variable", "geometry:margin=1in",
+        "--variable", "fontsize=11pt"
+      ];
+      
+      // Add font path if specified
+      if (PANDOC_CHINESE_FONT_PATH) {
+        chineseFontArgs.push("--variable", `fontdir:${PANDOC_CHINESE_FONT_PATH}`);
+      }
+      
+      args.push(...chineseFontArgs);
+    }
   }
 
   args.push(filePath);

src/helpers/env.ts

@@ -23,3 +23,10 @@ export const MAX_CONVERT_PROCESS =
 
 export const UNAUTHENTICATED_USER_SHARING =
   process.env.UNAUTHENTICATED_USER_SHARING?.toLowerCase() === "true" || false;
+
+export const PANDOC_ENABLE_CHINESE_FONT =
+  process.env.PANDOC_ENABLE_CHINESE_FONT?.toLowerCase() === "true" || false;
+
+export const PANDOC_CHINESE_FONT_PATH = process.env.PANDOC_CHINESE_FONT_PATH || "";
+
+export const PANDOC_CHINESE_FONT_FAMILY = process.env.PANDOC_CHINESE_FONT_FAMILY || "SimSun";