import path from "path";
import { createRequire } from "module";
import type { WorkflowContext } from "../run";
import type { WorkflowStep } from "../lib/parameters";

type CustomStepRunner = (
  context: WorkflowContext,
  step: WorkflowStep,
) => Promise<unknown> | unknown;

export const runCustomStep = async (
  context: WorkflowContext,
  step: WorkflowStep,
): Promise<void> => {
  const script = typeof step.script === "string" ? step.script : "";
  if (!script) {
    throw new Error(`Custom step ${step.id} requires a script path`);
  }

  const scriptPath = path.isAbsolute(script) ? script : path.join(context.root, script);
  const requireFromProject = createRequire(path.join(context.root, "package.json"));
  const module = requireFromProject(scriptPath) as {
    default?: CustomStepRunner;
    main?: CustomStepRunner;
    run?: CustomStepRunner;
  };
  const runner = module.default || module.main || module.run;

  if (typeof runner !== "function") {
    throw new Error(`Custom step script ${script} must export default, main, or run`);
  }

  const result = await runner(context, step);
  if (result && typeof result === "object") {
    context.reporter.result("execution", {
      stepId: step.id,
      kind: step.kind,
      mode: "custom",
      script,
      result,
    });
  }
};