import type { QuickJSContext, QuickJSHandle } from "quickjs-emscripten";

import { call } from "../vmutil";

import unmarshalProperties from "./properties";

export default function unmarshalObject(
  ctx: QuickJSContext,
  handle: QuickJSHandle,
  unmarshal: (handle: QuickJSHandle) => [unknown, boolean],
  preUnmarshal: <T>(target: T, handle: QuickJSHandle) => T | undefined,
): object | undefined {
  if (
    ctx.typeof(handle) !== "object" ||
    // null check
    ctx
      .unwrapResult(ctx.evalCode("o => o === null"))
      .consume(n => ctx.dump(ctx.unwrapResult(ctx.callFunction(n, ctx.undefined, handle))))
  )
    return;

  const raw = call(ctx, "Array.isArray", undefined, handle).consume(r => ctx.dump(r)) ? [] : {};
  const obj = preUnmarshal(raw, handle) ?? raw;

  const prototype = call(
    ctx,
    `o => {
      const p = Object.getPrototypeOf(o);
      return !p || p === Object.prototype || p === Array.prototype ? undefined : p;
    }`,
    undefined,
    handle,
  ).consume(prototype => {
    if (ctx.typeof(prototype) === "undefined") return;
    const [proto] = unmarshal(prototype);
    return proto;
  });
  if (typeof prototype === "object") {
    Object.setPrototypeOf(obj, prototype);
  }

  unmarshalProperties(ctx, handle, raw, unmarshal);

  return obj;
}