import {readFileSync} from "fs";
import * as path from "path";

const RE_INCLUDE = /^include\s+"((?:[^"]|\\")+)"\s*$/mg;

export function expandIncludes(
  scriptPath: string,
  excludedPaths: Set<string> = new Set()
): string {
  const script = String(readFileSync(scriptPath));
  const scriptDir = path.dirname(scriptPath);
  return script.replace(RE_INCLUDE, (match, location) => {
    const includePath = path.join(scriptDir, location);
    if (!excludedPaths.has(includePath)) {
      excludedPaths.add(includePath);
      return expandIncludes(includePath, excludedPaths);
    } else {
      return "";
    }
  });
}