convert to cli tool

index.ts

@@ -1,9 +1,31 @@
 import { renderMermaidSVG } from "beautiful-mermaid";
 
-const svg = renderMermaidSVG(`
-  graph TD
-    A[Start] --> B{Decision}
-    B -->|Yes| C[Action]
-    B -->|No| D[End]
-`);
-console.log(svg);
+const args = process.argv.slice(2);
+
+if (args.length < 2) {
+  console.error("Usage: bun index.ts <input.mmd> <output.svg>");
+  console.error("Example: bun index.ts diagram.mmd output.svg");
+  process.exit(1);
+}
+
+const [inputPath, outputPath] = args;
+
+try {
+  // Read the .mmd file
+  const diagramText = await Bun.file(inputPath).text();
+
+  // Render to SVG
+  const svg = renderMermaidSVG(diagramText);
+
+  // Write to output file
+  await Bun.write(outputPath, svg);
+
+  console.log(`✓ Generated SVG: ${outputPath}`);
+} catch (error) {
+  if (error instanceof Error && "code" in error && error.code === "ENOENT") {
+    console.error(`✗ Input file not found: ${inputPath}`);
+  } else {
+    console.error(`✗ Error: ${error instanceof Error ? error.message : String(error)}`);
+  }
+  process.exit(1);
+}