import type { AxiosRequestConfig, AxiosResponse } from "axios";
import type { ApiRequestOptions } from "./ApiRequestOptions";

type Headers = Record<string, string>;
type Middleware<T> = (value: T) => T | Promise<T>;
type Resolver<T> = (options: ApiRequestOptions<T>) => Promise<T>;

export class Interceptors<T> {
  _fns: Middleware<T>[];

  constructor() {
    this._fns = [];
  }

  eject(fn: Middleware<T>): void {
    const index = this._fns.indexOf(fn);
    if (index !== -1) {
      this._fns = [...this._fns.slice(0, index), ...this._fns.slice(index + 1)];
    }
  }

  use(fn: Middleware<T>): void {
    this._fns = [...this._fns, fn];
  }
}

export type OpenAPIConfig = {
  BASE: string;
  CREDENTIALS: "include" | "omit" | "same-origin";
  ENCODE_PATH?: ((path: string) => string) | undefined;
  HEADERS?: Headers | Resolver<Headers> | undefined;
  PASSWORD?: string | Resolver<string> | undefined;
  TOKEN?: string | Resolver<string> | undefined;
  USERNAME?: string | Resolver<string> | undefined;
  VERSION: string;
  WITH_CREDENTIALS: boolean;
  interceptors: {
    request: Interceptors<AxiosRequestConfig>;
    response: Interceptors<AxiosResponse>;
  };
};

export const OpenAPI: OpenAPIConfig = {
  BASE: "",
  CREDENTIALS: "include",
  ENCODE_PATH: undefined,
  HEADERS: undefined,
  PASSWORD: undefined,
  TOKEN: undefined,
  USERNAME: undefined,
  VERSION: "0.1.0",
  WITH_CREDENTIALS: false,
  interceptors: {
    request: new Interceptors(),
    response: new Interceptors(),
  },
};