/**

 * @param fields *(optional)* A list of fields to return in the response.

 * Reference parameters of sub-objects with dot notation.

 *

 * @param exclude_fields *(optional)* A list of fields to exclude from the response.

 * Reference parameters of sub-objects with dot notation. If both `fields` and `exclude_fields`

 * are present, then only `exclude_fields` will be used.

 */

type Mailchimp = {

  api_key: string;

  server: string;

};

export async function main(

  auth: Mailchimp,

  fields?: string[],

  exclude_fields?: string[],

  count?: number,

  offset?: number,

  sort_dir?: "" | "ASC" | "DESC",

  type?: "" | "regular" | "plaintext" | "absplit" | "rss" | "variate",

  status?: "" | "save" | "paused" | "schedule" | "sending" | "sent",

  before_send_time?: string,

  since_send_time?: string,

  before_create_time?: string,

  since_create_time?: string,

  list_id?: string,

  folder_id?: string,

  member_id?: string,

  sort_field?: "" | "create_time" | "send_time",

) {

  const url = new URL(`https://${auth.server}.api.mailchimp.com/3.0/campaigns`);

  const params = {

    fields,

    exclude_fields,

    count,

    offset,

    sort_dir,

    type,

    status,

    before_send_time,

    since_send_time,

    before_create_time,

    since_create_time,

    list_id,

    folder_id,

    member_id,

    sort_field,

  };

  for (const key in params) {

    const value = params[<keyof typeof params>key];

    if (value) {

      url.searchParams.append(

        key,

        Array.isArray(value) ? value.join(",") : "" + value,

      );

    }

  }

  const response = await fetch(url, {

    method: "GET",

    headers: {

      Authorization: `Bearer ${auth.api_key}`,

    },

  });

  if (!response.ok) {

    throw Error(await response.text());

  }

  return await response.json();

}