import environment from './environment';

const API_URL = `https://gitlab.com/api/v4/projects/${environment.gitlab.projectId}`;

export async function createIssue(params: CreateIssueParams): Promise<Issue> {
  const { description, labels, title } = params;
  const body: { [key: string]: string } = {
    description,
    title,
  };
  const headers = new Headers({
    'Content-Type': 'application/json',
    'PRIVATE-TOKEN': environment.gitlab.token,
  });

  if (labels) {
    body['labels'] = `${labels}`;
  }

  const response = await fetch(`${API_URL}/issues`, {
    body: JSON.stringify(body),
    headers,
    method: 'POST',
  });
  const issue = await response.json();

  return issue as unknown as Issue;
}

export async function createIssueComment(params: CreateIssueCommentParams): Promise<Issue | null> {
  const { description, iid } = params;
  const headers = new Headers({
    'Content-Type': 'application/json',
    'PRIVATE-TOKEN': environment.gitlab.token,
  });

  const response = await fetch(`${API_URL}/issues/${iid}/discussions`, {
    body: JSON.stringify({ body: description }),
    headers,
    method: 'POST',
  });
  const issue = await response.json();

  return issue as unknown as Issue | null;
}

export async function getIssue(params: GetIssueParams): Promise<Issue | null> {
  const { labels, not, state, title } = params;
  const headers = new Headers({
    'Content-Type': 'application/json',
    'PRIVATE-TOKEN': environment.gitlab.token,
  });
  const search = new URLSearchParams({ in: 'title', title });

  if (labels) {
    search.append('labels', `${labels}`);
  }

  if (not) {
    if (not.labels) {
      search.append('not[labels]', `${not.labels}`);
    }

    if (not.state) {
      search.append('not[state]', not.state);
    }
  }

  if (state) {
    search.append('state', state);
  }

  const response = await fetch(`${API_URL}/issues?${search}`, { headers });
  const issues: readonly Issue[] = (await response.json()) as unknown as readonly Issue[];

  return issues.find((issue) => issue.title === title) || null;
}

export async function updateIssue(params: UpdateIssueParams): Promise<Issue | null> {
  const { event, iid, labels, labelsToRemove } = params;
  const body: { [key: string]: string } = {};
  const headers = new Headers({
    'Content-Type': 'application/json',
    'PRIVATE-TOKEN': environment.gitlab.token,
  });

  if (event) {
    body['state_event'] = event;
  }

  if (labels) {
    body['labels'] = `${labels}`;
  }

  if (labelsToRemove) {
    body['remove_labels'] = `${labelsToRemove}`;
  }

  const response = await fetch(`${API_URL}/issues/${iid}`, {
    body: JSON.stringify(body),
    headers,
    method: 'PUT',
  });
  const issue = await response.json();

  return issue as unknown as Issue | null;
}

export interface CreateIssueParams {
  readonly description: string;
  readonly labels?: readonly string[];
  readonly title: string;
}

export interface CreateIssueCommentParams {
  readonly description: string;
  readonly iid: number;
}

export interface GetIssueParams {
  readonly labels?: readonly string[];
  readonly not?: Omit<GetIssueParams, 'not' | 'title'>;
  readonly state?: string;
  readonly title: string;
}

export interface Issue {
  readonly iid: number;
  readonly labels: readonly string[];
  readonly state: string;
  readonly title: string;
  readonly web_url: string;
}

export interface UpdateIssueParams {
  readonly event?: 'close' | 'reopen';
  readonly iid: number;
  readonly labels?: readonly string[];
  readonly labelsToRemove?: readonly string[];
}