Add commander lib to handle CLI

src/cli.js

@@ -1,4 +1,4 @@
-import process from "node:process";
+import { Command } from "commander";
 
 export const VALID_THEMES = [
   "light",
@@ -11,49 +11,42 @@ export const VALID_THEMES = [
   "nord-dark",
 ];
 
-export function parseArgs() {
-  const args = process.argv.slice(2);
-  const url = args[0];
-  const opts = { theme: null, css: null, prefs: null, output: null };
-  for (let i = 1; i < args.length; i++) {
-    if (args[i] === "--theme" && args[i + 1]) opts.theme = args[++i];
-    else if (args[i] === "--css" && args[i + 1]) opts.css = args[++i];
-    else if (args[i] === "--prefs" && args[i + 1]) opts.prefs = args[++i];
-    else if (args[i] === "--output" && args[i + 1]) opts.output = args[++i];
-  }
-  if (
-    !opts.theme &&
-    args[1] &&
-    !args[1].startsWith("-") &&
-    VALID_THEMES.includes(args[1])
-  ) {
-    opts.theme = args[1];
-  }
-  return { url, opts };
-}
+const program = new Command();
 
-export function printUsage() {
-  console.error("Usage: node src/index.js <URL> [theme] [options]");
-  console.error("");
-  console.error("Options:");
-  console.error(
-    "  --theme <theme>    Reader View theme (" + VALID_THEMES.join(", ") + ")",
+program
+  .name("html2pdf-reader")
+  .description("Convert web articles to PDF using Reader View and Puppeteer")
+  .argument("<url>", "URL of the article to convert")
+  .option(
+    "-t, --theme <theme>",
+    `Reader View theme (${VALID_THEMES.join(", ")})`,
+  )
+  .option("-c, --css <path>", "path to custom CSS file")
+  .option("-p, --prefs <path>", "path to extension preferences JSON")
+  .option(
+    "-o, --output <path>",
+    "output file path (default: ./output/<title>.pdf)",
+  )
+  .addHelpText(
+    "after",
+    `
+Examples:
+  node src/index.js <URL>
+  node src/index.js <URL> --theme dark --css config/rules.css
+  npm start -- <URL> --theme dark --css config/rules.css
+`,
   );
-  console.error("  --css <path>       Path to custom CSS file");
-  console.error("  --prefs <path>     Path to extension preferences JSON");
-  console.error(
-    "  --output <path>    Output file path (default: ./output/<title>.pdf)",
-  );
-  console.error("");
-  console.error("Examples:");
-  console.error("  node src/index.js <URL>");
-  console.error("  node src/index.js <URL> dark --css config/rules.css");
-  console.error("");
-  console.error("IMPORTANT: npm start consumes --flags as npm config.");
-  console.error("Use node directly or add -- before flags:");
-  console.error(
-    "  node src/index.js <URL> --theme dark --css config/rules.css",
-  );
-  console.error("  npm start -- <URL> --theme dark --css config/rules.css");
-  console.error("");
+
+export function parseArgs() {
+  program.parse(process.argv);
+  const opts = program.opts();
+  return {
+    url: program.args[0],
+    opts: {
+      theme: opts.theme || null,
+      css: opts.css || null,
+      prefs: opts.prefs || null,
+      output: opts.output || null,
+    },
+  };
 }