//
// Copyright 2021 DXOS.org
//

import chalk from 'chalk';
import fs from 'fs';
import path from 'path';

import { asyncExec } from './util';

export type Branch = {
  name: string
  current: boolean
  modified?: boolean
  status?: string
}

export type Repo = {
  dir: string
  name: string
  origin: string
  branches?: Branch[]
}

export const parseOrigin = (origin: string) => {
  const [, repo] = origin.match(/:(.*)\./) as any;
  return (repo.indexOf('/')  === -1 ? repo : `@${repo}`);
}

/**
 * Get root path of current repo or undefined if not in a repo directory.
 */
export const getRepo = async () => {
  try {
    return await asyncExec('git rev-parse --show-toplevel');
  } catch {
    return undefined;
  }
}

/**
 * Get list of repos.
 * @param root Optional root directory.
 */
export const getRepos = async (root?: string): Promise<Repo[]> => {
  // Memo current dir.
  const cwd = process.cwd();
  if (!root) {
    root = cwd;
  }

  const dirs = fs.readdirSync(root || cwd, { withFileTypes: true }).filter(f => f.isDirectory()).map(f => f.name);

  // Synchronously visit each directory.
  const repos = [];
  for (const f of dirs) {
    const dir = path.join(root!, f);
    process.chdir(dir);
    if (!fs.existsSync('.git')) {
      continue;
    }

    try {
      const origin = await asyncExec('git remote get-url origin');

      // Status of current branch.
      const status = await asyncExec(`git status -s -b`);
      const lines = status.split('\n');
      const [, match] = lines[0].match(/(\[.+\])/) ?? [];
      const modified = lines.length > 1;

      // https://stackoverflow.com/questions/2016901/viewing-unpushed-git-commits/30720302#30720302
      // git for-each-ref --format="%(HEAD)" refs/heads
      // git status --porcelain
      const result = await asyncExec('git branch --format "%(refname:short) %(HEAD)"');
      const branches = await Promise.all(result.split('\n').map(async line => {
        const [name, head] = line.split(' ');
        return {
          name,
          current: !!head,
          modified: !!head ? modified : false,
          status: !!head ? match : undefined
        };
      }));

      repos.push({
        dir,
        origin,
        name: parseRepo(origin),
        branches
      });
    } catch {
      console.log(chalk.red('Invalid directory:', f));
    }
  }

  // Change back.
  process.chdir(cwd);

  return (repos as Repo[]).filter(Boolean);
};

export const parseRepo = (repo: string) => {
  const match = repo.match(/.+:(.+)\./);
  return match && match.length > 1 ? match[1] : undefined;
};