import React, { useEffect, useMemo, useReducer } from "react";
import { ComponentDataSourceContext, ZappPipesDataProps } from "../types";

const generateStaticUrl = (component: ZappUIComponent) => {
  const { id, position } = component || {};

  return `static://component?id=${id}&position=${position}`;
};

const reducer = (state, action) => {
  switch (action.type) {
    case "SET_DATA":
      return { ...state, data: action.payload, loading: false };
    case "SET_ERROR":
      return { ...state, error: action.payload, loading: false };
    default:
      return state;
  }
};

type StaticFeedResolverProps = ComponentDataSourceContext & {
  children: (dataProps: ZappPipesDataProps) => React.ReactNode;
};

export function StaticFeedResolver({
  children,
  getStaticComponentFeed,
  component,
  componentIndex,
}: StaticFeedResolverProps) {
  const url = generateStaticUrl(component);

  const [{ loading, data, error }, dispatch] = useReducer(reducer, {
    loading: true,
    data: null,
    error: null,
  });

  useEffect(() => {
    const getData = async () => {
      try {
        const res = await getStaticComponentFeed({
          index: componentIndex,
          component,
        });

        dispatch({ type: "SET_DATA", payload: res });
      } catch (err) {
        dispatch({ type: "SET_ERROR", payload: err });
      }
    };

    if (getStaticComponentFeed) {
      getData();
    }
  }, [getStaticComponentFeed, component, componentIndex]);

  const reloadData = async () => {
    if (!getStaticComponentFeed) return Promise.resolve();

    try {
      const res = await getStaticComponentFeed({
        index: componentIndex,
        component,
      });

      dispatch({ type: "SET_DATA", payload: res });

      return res;
    } catch (err) {
      dispatch({ type: "SET_ERROR", payload: err });

      return Promise.reject(err);
    }
  };

  const zappPipesDataProps = useMemo(
    () => ({
      zappPipesData: { url, loading, data, error },
      reloadData,
      loadNextData: undefined, // Static resolver doesn't support pagination
    }),
    [url, loading, data, error]
  );

  return <>{children(zappPipesDataProps)}</>;
}