/**
 * @license
 * Copyright Google LLC All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */

import {alias, onUnion, params, types} from 'typed-graphqlify';

import {bold, debug, info} from '../../utils/console';
import {GitClient} from '../../utils/git/index';
import {CaretakerConfig} from '../config';

/**
 * Cap the returned issues in the queries to an arbitrary 100. At that point, caretaker has a lot
 * of work to do and showing more than that isn't really useful.
 */
const MAX_RETURNED_ISSUES = 20;

/** Retrieve the number of matching issues for each github query. */
export async function printGithubTasks(git: GitClient, config?: CaretakerConfig) {
  if (!config?.githubQueries?.length) {
    debug('No github queries defined in the configuration, skipping.');
    return;
  }
  info.group(bold(`Github Tasks`));
  await getGithubInfo(git, config);
  info.groupEnd();
  info();
}

/** Retrieve query match counts and log discovered counts to the console. */
async function getGithubInfo(git: GitClient, {githubQueries: queries = []}: CaretakerConfig) {
  /** The query object for graphql. */
  const graphQlQuery: {
    [key: string]: {
      issueCount: number,
      nodes: Array<{url: string}>,
    }
  } = {};
  /** The Github search filter for the configured repository. */
  const repoFilter = `repo:${git.remoteConfig.owner}/${git.remoteConfig.name}`;
  queries.forEach(({name, query}) => {
    /** The name of the query, with spaces removed to match GraphQL requirements. */
    const queryKey = alias(name.replace(/ /g, ''), 'search');
    graphQlQuery[queryKey] = params(
        {
          type: 'ISSUE',
          first: MAX_RETURNED_ISSUES,
          query: `"${repoFilter} ${query.replace(/"/g, '\\"')}"`,
        },
        {
          issueCount: types.number,
          nodes: [{...onUnion({
            PullRequest: {
              url: types.string,
            },
            Issue: {
              url: types.string,
            },
          })}],
        },
    );
  });
  /** The results of the generated github query. */
  const results = await git.github.graphql.query(graphQlQuery);
  Object.values(results).forEach((result, i) => {
    info(`${queries[i]?.name.padEnd(25)} ${result.issueCount}`);
    if (result.issueCount > 0) {
      const {owner, name: repo} = git.remoteConfig;
      const url = encodeURI(`https://github.com/${owner}/${repo}/issues?q=${queries[i]?.query}`);
      info.group(`${url}`);
      if (result.nodes.length === MAX_RETURNED_ISSUES && result.nodes.length < result.issueCount) {
        info(`(first ${MAX_RETURNED_ISSUES})`);
      }
      for (const node of result.nodes) {
        info(`- ${node.url}`);
      }
      info.groupEnd();
    }
  });
}