import GithubAPI from './GithubAPI.js';
import api from './api.js';
import Handlebars from 'handlebars';
import fs from 'fs/promises';
import { colorize } from './helpers/colorize.js';
import { getReleaseInfo } from './contributors.js';
import path from 'path';
import { fileURLToPath } from 'url';

const __dirname = path.dirname(fileURLToPath(import.meta.url));

const NOTIFY_PR_TEMPLATE = path.resolve(__dirname, '../templates/pr_published.hbs');

const normalizeTag = (tag) => (tag ? 'v' + tag.replace(/^v/, '') : '');

const GITHUB_BOT_LOGIN = 'github-actions[bot]';

const skipCollaboratorPRs = true;

class RepoBot {
  constructor(options) {
    const { owner, repo, templates } = options || {};

    this.templates = {
      published: NOTIFY_PR_TEMPLATE,
      ...templates,
    };

    this.github = api || new GithubAPI(owner, repo);

    this.owner = this.github.owner;
    this.repo = this.github.repo;
  }

  async addComment(targetId, message) {
    return this.github.createComment(targetId, message);
  }

  async notifyPRPublished(id, tag) {
    let pr;

    try {
      pr = await this.github.getPR(id);
    } catch (err) {
      if (err.response?.status === 404) {
        throw new Error(`PR #${id} not found (404)`);
      }

      throw err;
    }

    tag = normalizeTag(tag);

    const {
      merged,
      labels,
      user: { login, type },
    } = pr;

    const isBot = type === 'Bot';

    if (!merged) {
      return false;
    }

    await this.github.appendLabels(id, [tag]);

    if (
      isBot ||
      labels.find(({ name }) => name === 'automated pr') ||
      (skipCollaboratorPRs && (await this.github.isCollaborator(login)))
    ) {
      return false;
    }

    const comments = await this.github.getComments(id, { desc: true });

    const comment = comments.find(
      ({ body, user }) => user.login === GITHUB_BOT_LOGIN && body.indexOf('published in') >= 0
    );

    if (comment) {
      console.log(colorize()`Release comment [${comment.html_url}] already exists in #${pr.id}`);
      return false;
    }

    const author = await this.github.getUser(login);

    author.isBot = isBot;

    const message = await this.constructor.renderTemplate(this.templates.published, {
      id,
      author,
      release: {
        tag,
        url: `https://github.com/${this.owner}/${this.repo}/releases/tag/${tag}`,
      },
    });

    return await this.addComment(id, message);
  }

  async notifyPublishedPRs(tag) {
    tag = normalizeTag(tag);

    const release = await getReleaseInfo(tag);

    if (!release) {
      throw Error(colorize()`Can't get release info for ${tag}`);
    }

    const { merges } = release;

    console.log(colorize()`Found ${merges.length} PRs in ${tag}:`);

    let i = 0;

    for (const pr of merges) {
      try {
        console.log(colorize()`${i++}) Notify PR #${pr.id}`);
        const result = await this.notifyPRPublished(pr.id, tag);
        console.log('✔️', result ? 'Label, comment' : 'Label');
      } catch (err) {
        console.warn(colorize('green', 'red')`❌ Failed notify PR ${pr.id}: ${err.message}`);
      }
    }
  }

  static async renderTemplate(template, data) {
    return Handlebars.compile(String(await fs.readFile(template)))(data);
  }
}

export default RepoBot;