type Mailgun = {

  api_key: string;

};

export async function main(

  resource: Mailgun,

  data: {

    listAddress: string;

    member: {

      address: string;

      name?: string;

      vars?: Record<string, string>;

      subscribed?: boolean;

      upsert?: boolean;

    };

  }

) {

  const form = new FormData();

  form.append("address", data.member.address);

  form.append("name", data.member.name || "");

  form.append(

    "vars",

    data.member.vars ? JSON.stringify(data.member.vars) : "{}"

  );

  form.append("subscribed", data.member.subscribed);

  form.append("upsert", data.member.upsert);

  return (

    await fetch(

      `https://api.mailgun.net/v3/lists/${data.listAddress}/members`,

      {

        method: "POST",

        headers: {

          Authorization:

            "Basic " +

            Buffer.from(`api:${resource.api_key}`).toString("base64"),

        },

        body: form,

      }

    )

  ).json();

}