import { isNonEmptyArray } from '@sindresorhus/is';
import type { MergeStrategy } from '../../../config/types.ts';
import {
  CONFIG_GIT_URL_UNAVAILABLE,
  REPOSITORY_BLOCKED,
} from '../../../constants/error-messages.ts';
import { logger } from '../../../logger/index.ts';
import { coerceArray } from '../../../util/array.ts';
import * as hostRules from '../../../util/host-rules.ts';
import { regEx } from '../../../util/regex.ts';
import { parseUrl } from '../../../util/url.ts';
import { getPrBodyStruct } from '../pr-body.ts';
import type { GitUrlOption, Pr } from '../types.ts';
import type { PR, PRMergeMethod, Repo } from './types.ts';

export function smartLinks(body: string): string {
  return body
    ?.replace(regEx(/\]\(\.\.\/issues\//g), '](issues/')
    .replace(regEx(/\]\(\.\.\/pull\//g), '](pulls/');
}

export function trimTrailingApiPath(url: string): string {
  return url?.replace(regEx(/api\/v1\/?$/g), '');
}

export function getRepoUrl(
  repo: Repo,
  gitUrl: GitUrlOption | undefined,
  endpoint: string,
): string {
  if (gitUrl === 'ssh') {
    if (!repo.ssh_url) {
      throw new Error(CONFIG_GIT_URL_UNAVAILABLE);
    }
    logger.debug(`Using SSH URL: ${repo.ssh_url}`);
    return repo.ssh_url;
  }

  // Find options for current host and determine Git endpoint
  const opts = hostRules.find({
    hostType: 'gitea',
    url: endpoint,
  });

  if (gitUrl === 'endpoint') {
    const url = parseUrl(endpoint);
    if (!url) {
      throw new Error(CONFIG_GIT_URL_UNAVAILABLE);
    }
    url.username = opts.token ?? '';
    url.pathname = `${url.pathname}${repo.full_name}.git`;
    logger.debug(
      { url: url.toString() },
      'using URL based on configured endpoint',
    );
    return url.toString();
  }

  if (!repo.clone_url) {
    throw new Error(CONFIG_GIT_URL_UNAVAILABLE);
  }

  logger.debug(`Using HTTP URL: ${repo.clone_url}`);
  const repoUrl = parseUrl(repo.clone_url);
  if (!repoUrl) {
    throw new Error(CONFIG_GIT_URL_UNAVAILABLE);
  }
  repoUrl.username = opts.token ?? '';
  return repoUrl.toString();
}

export function getMergeMethod(
  strategy: MergeStrategy | undefined,
): PRMergeMethod | null {
  switch (strategy) {
    case 'fast-forward':
      return 'rebase';
    case 'merge-commit':
      return 'merge';
    case 'rebase':
      return 'rebase-merge';
    case 'squash':
      return strategy;
    case 'auto':
    default:
      return null;
  }
}

export const API_PATH = '/api/v1';

export const DRAFT_PREFIX = 'WIP: ';
const reconfigurePrRegex = regEx(/reconfigure$/);

export function toRenovatePR(data: PR, author: string | null): Pr | null {
  if (!data) {
    return null;
  }

  if (
    !data.base?.ref ||
    !data.head?.label ||
    !data.head?.sha ||
    !data.head?.repo?.full_name
  ) {
    logger.trace(
      `Skipping Pull Request #${data.number} due to missing base and/or head branch`,
    );
    return null;
  }

  const createdBy = data.user?.login;
  if (
    createdBy &&
    author &&
    !reconfigurePrRegex.test(data.head.label) &&
    createdBy !== author
  ) {
    return null;
  }

  let title = data.title;
  let isDraft = false;
  if (title.startsWith(DRAFT_PREFIX)) {
    title = title.substring(DRAFT_PREFIX.length);
    isDraft = true;
  }
  const labels = coerceArray(data?.labels).map((l) => l.name);

  return {
    labels,
    number: data.number,
    state: data.merged ? 'merged' : data.state,
    title,
    isDraft,
    bodyStruct: getPrBodyStruct(data.body),
    sha: data.head.sha,
    sourceBranch: data.head.label,
    targetBranch: data.base.ref,
    sourceRepo: data.head.repo.full_name,
    createdAt: data.created_at,
    cannotMergeReason: data.mergeable
      ? undefined
      : `pr.mergeable="${data.mergeable}"`,
    hasAssignees: !!(data.assignee?.login ?? isNonEmptyArray(data.assignees)),
  };
}

/**
 * Check if a repository is usable.
 * A repo isn't usable if one of the following conditions is met:
 * - The repo is a `mirror`
 * - We don't have pull or push permissions
 * - Pull requests are disabled
 * @param repo Repo to check
 * @returns  `true` if the repository is usable, `false` otherwise
 */
export function usableRepo(repo: Repo): boolean {
  if (repo.mirror === true) {
    return false;
  }

  if (repo.permissions.pull === false || repo.permissions.push === false) {
    logger.debug(
      `Skipping repository ${repo.full_name} because of missing pull or push permissions`,
    );
    return false;
  }

  if (repo.has_pull_requests === false) {
    logger.debug(
      `Skipping repository ${repo.full_name} because pull requests are disabled`,
    );
    return false;
  }
  return true;
}

export function isAllowed(style: PRMergeMethod, repo: Repo): boolean {
  switch (style) {
    case 'merge':
      return repo.allow_merge_commits;
    case 'rebase':
      return repo.allow_rebase;
    case 'rebase-merge':
      return repo.allow_rebase_explicit;
    case 'squash':
      return repo.allow_squash_merge;
    case 'fast-forward-only':
      return repo.allow_fast_forward_only_merge;
  }
  logger.debug('Repo has unknown merge style - aborting renovation');
  throw new Error(REPOSITORY_BLOCKED);
}