Adds in a second converter program

bin/nbt2snbt.dart

@@ -1,5 +1,51 @@
+import 'dart:io';
+
+import 'package:libac_dart/argparse/Args.dart';
+import 'package:libac_dart/argparse/Builder.dart';
+import 'package:libac_dart/argparse/CLIHelper.dart';
+import 'package:libac_dart/argparse/types/Bool.dart';
+import 'package:libac_dart/argparse/types/String.dart';
+import 'package:libac_dart/nbt/NbtIo.dart';
+import 'package:libac_dart/nbt/SnbtIo.dart';
+import 'package:libac_dart/nbt/impl/CompoundTag.dart';
+import 'package:nbteditor/Consts2.dart';
+
+const HEADER =
+    "nbt2snbt\nCopyright Piccari Creations 2024 - Tara Piccari\nVersion: ${VERSION}\n\n";
 void main(List<String> args) async {
-  for (int i = 0; i < args.length; i++) {
-    print("ARG ${i}: ${args[i]}");
+  Arguments usage = ArgumentsBuilder.builder()
+      .withArgument(
+          BoolArgument(name: "help", description: "Print this output"))
+      .withArgument(StringArgument(
+          name: "input", value: "%", description: "The input file to convert"))
+      .withArgument(StringArgument(
+          name: "out",
+          value: "%",
+          description:
+              "The path to the output file. If not supplied, STDOUT is used."))
+      .build();
+
+  Arguments defaults = Arguments();
+  Arguments vArgs = await CLIHelper.parseArgs(args, defaults);
+
+  if (vArgs.hasArg("help") || vArgs.count == 0) {
+    print(HEADER);
+    print(CLIHelper.makeArgCLIHelp(usage));
+  } else {
+    if (!vArgs.hasArg("input")) {
+      print(HEADER);
+      print("Missing required argument: input");
+      exit(1);
+    }
+    String file = vArgs.getArg("input")!.getValue() as String;
+
+    CompoundTag ct = await NbtIo.read(file);
+
+    if (!vArgs.hasArg("out")) {
+      print(SnbtIo.writeToString(ct));
+    } else {
+      SnbtIo.writeToFile(vArgs.getArg("out")!.getValue() as String, ct);
+      print("Wrote SNBT output to file");
+    }
   }
 }