/**
 * See the NOTICE file distributed with this work for additional information
 * regarding copyright ownership.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

type FormFieldType = string | File | File[] | null;

type Form = Record<string, FormFieldType>;

type TokenSuccessResponse = {
  token: string;
};

export const submitForm = async (form: Form) => {
  const formData = buildFormData(form);
  const url = '/api/support/ticket';
  const token = await getToken();

  return fetch(url, {
    method: 'POST',
    headers: {
      Authorization: `Bearer ${token}`
    },
    body: formData
  }).then(async (response) => {
    let responseMessage;
    try {
      responseMessage = await response.json();
    } catch {
      throw new Error();
    }
    if (!response.ok) {
      throw new Error(responseMessage);
    } else {
      return responseMessage;
    }
  });
};

const buildFormData = (form: Form) => {
  const formData = new FormData(); // note that FormData can only contain unicode strings and blobs, including files
  const formEntries = Object.entries(form);
  for (const [fieldName, value] of formEntries) {
    addToFormData(formData, fieldName, value);
  }
  return formData;
};

const addToFormData = (
  formData: FormData,
  fieldName: string,
  value: FormFieldType
) => {
  if (value === null) {
    return;
  } else if (Array.isArray(value)) {
    for (const item of value) {
      addToFormData(formData, fieldName, item);
    }
  } else if (value instanceof File) {
    formData.append(fieldName, value, value.name);
  } else {
    formData.append(fieldName, value);
  }
};

const getToken = async () => {
  const url = '/api/support/token';
  const { token } = (await fetch(url).then((response) =>
    response.json()
  )) as TokenSuccessResponse;
  return token;
};