import { compile, pathToRegexp, Key } from 'path-to-regexp';
import type { BFFRequestPayload, RequestCreator, Sender, Fetcher } from '.';

const globalFetch = fetch;

export const createRequest: RequestCreator = (
  path,
  method,
  port,
  fetch = globalFetch,
) => {
  const getFinalPath = compile(path, { encode: encodeURIComponent });
  const keys: Key[] = [];
  pathToRegexp(path, keys);

  const sender: Sender = async (...args) => {
    const fetcher = getFetcher(sender) || fetch;

    const payload: BFFRequestPayload =
      typeof args[args.length - 1] === 'object' ? args[args.length - 1] : {};
    payload.params = payload.params || {};
    keys.forEach((key, index) => {
      payload.params![key.name] = args[index];
    });

    const finalPath = getFinalPath(payload.params);
    const finalURL = payload.query
      ? `${finalPath}?${qsStringify(payload.query)}`
      : finalPath;
    const headers = payload.headers || {};
    let body: any =
      payload.data && typeof payload.data === 'object'
        ? JSON.stringify(payload.data)
        : payload.body;

    if (payload.data) {
      headers['Content-Type'] = 'application/json';

      body =
        typeof payload.data === 'object'
          ? JSON.stringify(payload.data)
          : payload.body;
    } else if (payload.body) {
      headers['Content-Type'] = 'text/plain';
      // eslint-disable-next-line prefer-destructuring
      body = payload.body;
    } else if (payload.formData) {
      body = payload.formData;
      // https://stackoverflow.com/questions/44919424/bad-content-type-header-no-multipart-boundary-nodejs
      // need multipart boundary aotu attached by browser when multipart is true
      // headers['Content-Type'] = 'multipart/form-data';
    } else if (payload.formUrlencoded) {
      headers['Content-Type'] = 'application/x-www-form-urlencoded';
      if (
        typeof payload.formUrlencoded === 'object' &&
        // eslint-disable-next-line @typescript-eslint/ban-ts-comment
        // @ts-expect-error
        // eslint-disable-next-line node/prefer-global/url-search-params,node/no-unsupported-features/node-builtins
        !(payload.formUrlencoded instanceof URLSearchParams)
      ) {
        body = qsStringify(payload.formUrlencoded);
      } else {
        body = payload.formUrlencoded;
      }
    }

    return fetcher(finalURL, {
      method,
      body,
      headers,
      // eslint-disable-next-line promise/prefer-await-to-then
    }).then(res => res.json());
  };

  return sender;
};

const getFetcher = (sender: Sender): Fetcher => {
  if (sender.fetch) {
    return sender.fetch;
  }

  return fetch;
};

const qsStringify = (input: Record<string, any>) => {
  const tupleList: string[] = [];

  for (const p in input) {
    if (input.hasOwnProperty(p)) {
      tupleList.push(
        `${encodeURIComponent(p)}=${encodeURIComponent(input[p])}`,
      );
    }
  }

  return tupleList.join('&');
};