/**
 * @copyright NHCarrigan
 * @license Naomi's Public License
 * @author Naomi Carrigan
 */

import { logger } from "../utils/logger.js";
import type { Amari } from "../interfaces/amari.js";
import type { IssueCreated,
  PullRequestCreated,
  GithubPayload } from "../interfaces/github.js";
import type { FastifyRequest, FastifyReply } from "fastify";

const isIssue = (body: GithubPayload): body is IssueCreated => {
  return "issue" in body;
};

const isPull = (body: GithubPayload): body is PullRequestCreated => {
  return "pull_request" in body;
};

/**
 * Handles a payload from a GitHub webhook.
 * @param amari - Amari's instance.
 * @param request - The Fastify request payload.
 * @param response - The Fastify reply class.
 */
// eslint-disable-next-line max-statements, max-lines-per-function -- STFU.
export const processGithubEvent = async(
  amari: Amari,
  request: FastifyRequest<{
    // eslint-disable-next-line @typescript-eslint/naming-convention -- Fastify standard.
    Body:        GithubPayload;
    // eslint-disable-next-line @typescript-eslint/naming-convention -- Fastify standard.
    Querystring: { secret: string };
  }>,
  response: FastifyReply,
): Promise<void> => {
  const { secret } = request.query;
  if (secret !== process.env.GH_WEBHOOK_SECRET) {
    await response.status(403).send({
      message: "Invalid secret provided!",
    });
  }
  const event = request.headers["x-github-event"];
  if (typeof event !== "string") {
    await response.status(400).
      send({ message: "Invalid GitHub event header." });
    return;
  }
  if (event === "ping") {
    await response.status(200).send({ message: "Pong!" });
    return;
  }
  const { action } = request.body;
  await response.status(200).send({ message: "Payload received!" });
  if (action === "opened" && event === "issues" && isIssue(request.body)) {
    await logger.log("info", "Processing new issue");
    const { issue, repository } = request.body;
    const { number } = issue;
    const { owner, name } = repository;
    await amari.github.rest.issues.addAssignees({
      assignees:    [ "naomi-lgbt" ],
      // eslint-disable-next-line @typescript-eslint/naming-convention -- Github SDK requirement.
      issue_number: number,
      owner:        owner.login,
      repo:         name,
    });
    return;
  }
  if (action === "opened" && event === "pull_request" && isPull(request.body)) {
    await logger.log("info", "Processing new PR");
    const { pull_request: pr, repository } = request.body;
    const { number } = pr;
    const { owner, name } = repository;
    await amari.github.rest.pulls.requestReviewers({
      owner:       owner.login,
      // eslint-disable-next-line @typescript-eslint/naming-convention -- Github SDK requirement.
      pull_number: number,
      repo:        name,
      reviewers:   [ "naomi-lgbt" ],
    });
  }
};