Re-structure and decouple AST from generator

wasm-synth/src/main.rs

@@ -0,0 +1,75 @@
+use parity_wasm::{deserialize_file, elements::Module};
+
+use codegen_luajit::gen::Generator as LuaJIT;
+use codegen_luau::gen::Generator as Luau;
+use wasm_ast::writer::Transpiler;
+
+fn parse_module(name: &str) -> Module {
+	let wasm = deserialize_file(name).expect("Failed to parse Wasm file");
+
+	match wasm.parse_names() {
+		Ok(n) => n,
+		Err(n) => n.1,
+	}
+}
+
+fn run_translator<'a, T: Transpiler<'a>>(wasm: &'a Module) {
+	let module = T::new(wasm);
+	let output = std::io::stdout();
+
+	module
+		.transpile(&mut output.lock())
+		.expect("Failed to transpile");
+}
+
+fn run_runtime<'a, T: Transpiler<'a>>() {
+	let output = std::io::stdout();
+
+	T::runtime(&mut output.lock()).expect("Failed to fetch runtime");
+}
+
+fn do_translate(name: &str, file: &str) {
+	let wasm = &parse_module(file);
+
+	match name.to_lowercase().as_str() {
+		"luajit" => run_translator::<LuaJIT>(wasm),
+		"luau" => run_translator::<Luau>(wasm),
+		_ => panic!("Bad language: {}", name),
+	}
+}
+
+fn do_runtime(name: &str) {
+	match name.to_lowercase().as_str() {
+		"luajit" => run_runtime::<LuaJIT>(),
+		"luau" => run_runtime::<Luau>(),
+		_ => panic!("Bad runtime: {}", name),
+	}
+}
+
+fn do_help() {
+	println!("usage: program translate <lang> <file>");
+	println!("  or:  program runtime <lang>");
+	println!("  or:  program help");
+}
+
+fn main() {
+	let mut args = std::env::args().skip(1);
+
+	match args.next().as_deref().unwrap_or("help") {
+		"help" => do_help(),
+		"runtime" => {
+			let lang = args.next().expect("No runtime specified");
+
+			do_runtime(&lang);
+		}
+		"translate" => {
+			let lang = args.next().expect("No language specified");
+			let file = args.next().expect("No file specified");
+
+			do_translate(&lang, &file);
+		}
+		bad => {
+			eprintln!("Bad action `{}`; try `help`", bad);
+		}
+	}
+}