<?php declare(strict_types=1);

/*
 * This file is part of Composer.
 *
 * (c) Nils Adermann <naderman@naderman.de>
 *     Jordi Boggiano <j.boggiano@seld.be>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Composer\Repository\Vcs;

use Composer\Config;
use Composer\Cache;
use Composer\Pcre\Preg;
use Composer\Util\Hg as HgUtils;
use Composer\Util\ProcessExecutor;
use Composer\Util\Filesystem;
use Composer\IO\IOInterface;

/**
 * @author Per Bernhardt <plb@webfactory.de>
 */
class HgDriver extends VcsDriver
{
    /** @var array<int|string, string> Map of tag name to identifier */
    protected $tags;
    /** @var array<int|string, string> Map of branch name to identifier */
    protected $branches;
    /** @var string */
    protected $rootIdentifier;
    /** @var string */
    protected $repoDir;

    /**
     * @inheritDoc
     */
    public function initialize(): void
    {
        if (Filesystem::isLocalPath($this->url)) {
            $this->repoDir = $this->url;
        } else {
            if (!Cache::isUsable($this->config->get('cache-vcs-dir'))) {
                throw new \RuntimeException('HgDriver requires a usable cache directory, and it looks like you set it to be disabled');
            }

            $cacheDir = $this->config->get('cache-vcs-dir');
            $this->repoDir = $cacheDir . '/' . Preg::replace('{[^a-z0-9]}i', '-', $this->url) . '/';

            $fs = new Filesystem();
            $fs->ensureDirectoryExists($cacheDir);

            if (!is_writable(dirname($this->repoDir))) {
                throw new \RuntimeException('Can not clone '.$this->url.' to access package information. The "'.$cacheDir.'" directory is not writable by the current user.');
            }

            // Ensure we are allowed to use this URL by config
            $this->config->prohibitUrlByConfig($this->url, $this->io);

            $hgUtils = new HgUtils($this->io, $this->config, $this->process);

            // update the repo if it is a valid hg repository
            if (is_dir($this->repoDir) && 0 === $this->process->execute('hg summary', $output, $this->repoDir)) {
                if (0 !== $this->process->execute('hg pull', $output, $this->repoDir)) {
                    $this->io->writeError('<error>Failed to update '.$this->url.', package information from this repository may be outdated ('.$this->process->getErrorOutput().')</error>');
                }
            } else {
                // clean up directory and do a fresh clone into it
                $fs->removeDirectory($this->repoDir);

                $repoDir = $this->repoDir;
                $command = function ($url) use ($repoDir): string {
                    return sprintf('hg clone --noupdate -- %s %s', ProcessExecutor::escape($url), ProcessExecutor::escape($repoDir));
                };

                $hgUtils->runCommand($command, $this->url, null);
            }
        }

        $this->getTags();
        $this->getBranches();
    }

    /**
     * @inheritDoc
     */
    public function getRootIdentifier(): string
    {
        if (null === $this->rootIdentifier) {
            $this->process->execute(sprintf('hg tip --template "{node}"'), $output, $this->repoDir);
            $output = $this->process->splitLines($output);
            $this->rootIdentifier = $output[0];
        }

        return $this->rootIdentifier;
    }

    /**
     * @inheritDoc
     */
    public function getUrl(): string
    {
        return $this->url;
    }

    /**
     * @inheritDoc
     */
    public function getSource(string $identifier): array
    {
        return array('type' => 'hg', 'url' => $this->getUrl(), 'reference' => $identifier);
    }

    /**
     * @inheritDoc
     */
    public function getDist(string $identifier): ?array
    {
        return null;
    }

    /**
     * @inheritDoc
     */
    public function getFileContent(string $file, string $identifier): ?string
    {
        if (isset($identifier[0]) && $identifier[0] === '-') {
            throw new \RuntimeException('Invalid hg identifier detected. Identifier must not start with a -, given: ' . $identifier);
        }

        $resource = sprintf('hg cat -r %s -- %s', ProcessExecutor::escape($identifier), ProcessExecutor::escape($file));
        $this->process->execute($resource, $content, $this->repoDir);

        if (!trim($content)) {
            return null;
        }

        return $content;
    }

    /**
     * @inheritDoc
     */
    public function getChangeDate(string $identifier): ?\DateTimeImmutable
    {
        $this->process->execute(
            sprintf(
                'hg log --template "{date|rfc3339date}" -r %s',
                ProcessExecutor::escape($identifier)
            ),
            $output,
            $this->repoDir
        );

        return new \DateTimeImmutable(trim($output), new \DateTimeZone('UTC'));
    }

    /**
     * @inheritDoc
     */
    public function getTags(): array
    {
        if (null === $this->tags) {
            $tags = array();

            $this->process->execute('hg tags', $output, $this->repoDir);
            foreach ($this->process->splitLines($output) as $tag) {
                if ($tag && Preg::isMatch('(^([^\s]+)\s+\d+:(.*)$)', $tag, $match)) {
                    $tags[$match[1]] = $match[2];
                }
            }
            unset($tags['tip']);

            $this->tags = $tags;
        }

        return $this->tags;
    }

    /**
     * @inheritDoc
     */
    public function getBranches(): array
    {
        if (null === $this->branches) {
            $branches = array();
            $bookmarks = array();

            $this->process->execute('hg branches', $output, $this->repoDir);
            foreach ($this->process->splitLines($output) as $branch) {
                if ($branch && Preg::isMatch('(^([^\s]+)\s+\d+:([a-f0-9]+))', $branch, $match) && $match[1][0] !== '-') {
                    $branches[$match[1]] = $match[2];
                }
            }

            $this->process->execute('hg bookmarks', $output, $this->repoDir);
            foreach ($this->process->splitLines($output) as $branch) {
                if ($branch && Preg::isMatch('(^(?:[\s*]*)([^\s]+)\s+\d+:(.*)$)', $branch, $match) && $match[1][0] !== '-') {
                    $bookmarks[$match[1]] = $match[2];
                }
            }

            // Branches will have preference over bookmarks
            $this->branches = array_merge($bookmarks, $branches);
        }

        return $this->branches;
    }

    /**
     * @inheritDoc
     */
    public static function supports(IOInterface $io, Config $config, string $url, bool $deep = false): bool
    {
        if (Preg::isMatch('#(^(?:https?|ssh)://(?:[^@]+@)?bitbucket.org|https://(?:.*?)\.kilnhg.com)#i', $url)) {
            return true;
        }

        // local filesystem
        if (Filesystem::isLocalPath($url)) {
            $url = Filesystem::getPlatformPath($url);
            if (!is_dir($url)) {
                return false;
            }

            $process = new ProcessExecutor($io);
            // check whether there is a hg repo in that path
            if ($process->execute('hg summary', $output, $url) === 0) {
                return true;
            }
        }

        if (!$deep) {
            return false;
        }

        $process = new ProcessExecutor($io);
        $exit = $process->execute(sprintf('hg identify -- %s', ProcessExecutor::escape($url)), $ignored);

        return $exit === 0;
    }
}