import { AxiosInstance } from "axios";
import { TrackInfo } from "./info";
import { appendURL, kindMismatchError, PaginatedQuery } from "./util";

const baseURL = "https://api-v2.soundcloud.com/users/";

export interface Like {
  // eslint-disable-next-line camelcase
  created_at: string;
  kind: string;
  track: TrackInfo;
}

export interface GetLikesOptions {
  profileUrl?: string;
  id?: number;
  limit?: number; // -1 indicates no limit
  offset?: number;
  nextHref?: string;
}

/** @internal */
export const getLikes = async (
  options: GetLikesOptions,
  clientID: string,
  axiosInstance: AxiosInstance
): Promise<PaginatedQuery<Like>> => {
  let u = "";
  if (!options.nextHref) {
    if (!options.limit) options.limit = -1;
    if (!options.offset) options.offset = 0;
    u = appendURL(
      `https://api-v2.soundcloud.com/users/${options.id}/likes`,
      "client_id",
      clientID,
      "limit",
      "" + (options.limit === -1 ? 200 : options.limit),
      "offset",
      "" + options.offset
    );
  } else {
    u = appendURL(options.nextHref, "client_id", clientID);
  }

  let response: PaginatedQuery<Like>;
  let nextHref = "start";

  // If options.limit > 0, query each page of likes until we have collected
  // `options.limit` liked tracks.
  // If options.limit === -1, query every page of likes
  if (!options) {
    throw new Error("Options are required");
  }
  if (!options.limit) {
    options.limit = -1; // assume default if not provided
  }
  while (nextHref && (options.limit > 0 || options.limit === -1)) {
    const { data } = await axiosInstance.get(u);

    const query = data as PaginatedQuery<Like>;
    if (!query.collection) throw new Error("Invalid JSON response received");
    if (query.collection.length === 0) return data;

    if (query.collection[0].kind !== "like")
      throw kindMismatchError("like", query.collection[0].kind);

    // Only add tracks (for now)
    query.collection = query.collection.reduce<Like[]>(
      (prev, curr) => (curr.track ? prev.concat(curr) : prev),
      []
    );
    if (!response!) {
      response = query;
    } else {
      response.collection.push(...query.collection);
    }

    if (options.limit !== -1) {
      options.limit -= query.collection.length;
      // We have collected enough likes
      if (options.limit <= 0) break;
    }

    nextHref = query.next_href;
    if (nextHref) {
      if (options.limit !== -1) {
        const url = new URL(nextHref);
        url.searchParams.set("limit", "" + options.limit);
        nextHref = url.toString();
      }
      u = appendURL(nextHref, "client_id", clientID);
    }
  }

  if (!response!) {
    throw new Error("No response received");
  }

  return response;
};