rspack 0.0.1

use std::{sync::Arc, path::Path};

use once_cell::sync::Lazy;
use swc::{Compiler, common::{FilePathMapping, SourceMap, FileName}, config::IsModule};
use swc_ecma_parser::{Syntax, TsConfig, EsConfig};

static COMPILER: Lazy<Arc<Compiler>> = Lazy::new(|| {
  let cm = Arc::new(SourceMap::new(FilePathMapping::empty()));

  Arc::new(Compiler::new(cm))
});

pub fn get_compiler() -> Arc<Compiler> {
  COMPILER.clone()
}

pub fn parse_file(source_code: String, filename: &str) -> swc_ecma_ast::Module {
  let p = Path::new(filename);
  let ext = p.extension().and_then(|ext| ext.to_str()).unwrap_or("js");
  let syntax = if ext == "ts" || ext == "tsx" {
      Syntax::Typescript(TsConfig {
          decorators: false,
          tsx: ext == "tsx",
          ..Default::default()
      })
  } else {
      Syntax::Es(EsConfig {
          static_blocks: true,
          private_in_object: true,
          import_assertions: true,
          jsx: ext == "jsx",
          export_default_from: true,
          decorators_before_export: true,
          decorators: true,
          fn_bind: true,
          allow_super_outside_method: true,
      })
  };
  let compiler = get_compiler();
  let fm = compiler
      .cm
      .new_source_file(FileName::Custom(filename.to_string()), source_code);
  swc::try_with_handler(compiler.cm.clone(), Default::default(), |handler| {
      compiler.parse_js(
          fm,
          handler,
          swc_ecma_ast::EsVersion::Es2022,
          syntax,
          IsModule::Bool(true),
          None,
      )
  })
  .unwrap()
  .expect_module()
}