Installer.php

<?php

namespace Higidi\ComposerPhpCSStandardsPlugin;

use Composer\Composer;
use Composer\Installer\BinaryInstaller;
use Composer\Installer\LibraryInstaller;
use Composer\IO\IOInterface;
use Composer\Package\PackageInterface;
use Composer\Repository\InstalledRepositoryInterface;
use Composer\Util\Filesystem;
use Symfony\Component\Finder\Finder;
use Symfony\Component\Filesystem\Filesystem as SymfonyFilesystem;
use Higidi\ComposerPhpCSStandardsPlugin\PHPCodeSniffer\Standard;
use Higidi\ComposerPhpCSStandardsPlugin\PHPCodeSniffer\Standards;

class Installer extends LibraryInstaller
{
    const TYPE = 'php-codesniffer-standards';

    /**
     * Initializes library installer.
     *
     * @param IOInterface $io
     * @param Composer $composer
     * @param string $type
     * @param Filesystem $filesystem
     * @param BinaryInstaller $binaryInstaller
     */
    public function __construct(
        IOInterface $io,
        Composer $composer,
        $type = self::TYPE,
        Filesystem $filesystem = null,
        BinaryInstaller $binaryInstaller = null
    ) {
        parent::__construct($io, $composer, $type, $filesystem, $binaryInstaller);
    }

    /**
     * {@inheritDoc}
     */
    public function isInstalled(InstalledRepositoryInterface $repo, PackageInterface $package)
    {
        $isInstalled = parent::isInstalled($repo, $package);
        $sourceStandards = $this->getSourceStandards($package);
        $destinationStandards = $this->getDestinationStandards($repo);

        foreach ($sourceStandards as $sourceStandard) {
            if (!$destinationStandards->hasStandard($sourceStandard)
                || !$this->compareStandards($sourceStandard, $destinationStandards->getStandard($sourceStandard))
            ) {
                $isInstalled = false;
                break;
            }
        }

        return $isInstalled;
    }

    /**
     * {@inheritDoc}
     */
    public function install(InstalledRepositoryInterface $repo, PackageInterface $package)
    {
        parent::install($repo, $package);
        $this->installStandards($repo, $package);
    }

    /**
     * {@inheritDoc}
     */
    public function update(InstalledRepositoryInterface $repo, PackageInterface $initial, PackageInterface $target)
    {
        parent::update($repo, $initial, $target);
        $this->installStandards($repo, $target, $initial ? false : true);
    }


    /**
     * {@inheritDoc}
     */
    public function uninstall(InstalledRepositoryInterface $repo, PackageInterface $package)
    {
        if (!$repo->hasPackage($package)) {
            throw new \InvalidArgumentException('Package is not installed: '.$package);
        }
        $this->removeStandards($repo, $package);
        parent::uninstall($repo, $package);
    }

    /**
     * @param InstalledRepositoryInterface $repo
     * @param PackageInterface $package
     * @param bool $override
     * @return void
     */
    protected function installStandards(InstalledRepositoryInterface $repo, PackageInterface $package, $override = false)
    {
        $filesystem = new SymfonyFilesystem();
        $sourceStandards = $this->getSourceStandards($package);
        $destStandardsBasePath = $this->getPHPCodeSnifferStandardsBasePath($repo);
        foreach ($sourceStandards as $sourceStandard) {
            $sourcePath = $sourceStandard->getPath();
            $destPath = $destStandardsBasePath . DIRECTORY_SEPARATOR . $sourceStandard->getName();
            $filesystem->mirror($sourcePath, $destPath, null, array('override' => $override));
        }
    }

    /**
     * @param InstalledRepositoryInterface $repo
     * @param PackageInterface $package
     * @return void
     */
    protected function removeStandards(InstalledRepositoryInterface $repo, PackageInterface $package)
    {
        $sourceStandards = $this->getSourceStandards($package);
        $destinationStandards = $this->getDestinationStandards($repo);
        foreach ($sourceStandards as $sourceStandard) {
            if (!$destinationStandards->hasStandard($sourceStandard)) {
                continue;
            }
            $destinationStandard = $destinationStandards->getStandard($sourceStandard);

            $this->filesystem->removeDirectory($destinationStandard->getPath());
        }
    }

    /**
     * Get source (provided by the composer package) standards for package.
     *
     * @param PackageInterface $package
     * @return Standards
     */
    protected function getSourceStandards(PackageInterface $package)
    {
        $basePath = $this->getInstallPath($package);

        return $this->findStandards($basePath);
    }

    /**
     * Get destination (provided by PHPCodeSniffer) standards.
     *
     * @param InstalledRepositoryInterface $repo
     * @return Standards
     */
    protected function getDestinationStandards(InstalledRepositoryInterface $repo)
    {
        $basePath = $this->getPHPCodeSnifferInstallPath($repo);

        return $this->findStandards($basePath);
    }

    /**
     * @param Standard $source
     * @param Standard $destination
     * @return bool
     */
    protected function compareStandards(Standard $source, Standard $destination)
    {
        return $source->getName() === $destination->getName()
            && sha1($source->getRuleSetXmlPath()) === sha1($destination->getRuleSetXmlPath());
    }

    /**
     * @param string $basePath
     * @return Standards
     */
    protected function findStandards($basePath)
    {
        $standards = new Standards();
        $finder = new Finder();
        $finder
            ->in($basePath . '/**/Standards/*/')
            ->files()->name('ruleset.xml');
        foreach ($finder as $ruleSetFile) {
            $standard = new Standard($ruleSetFile->getPath());
            $standards->addStandard($standard);
        }

        return $standards;
    }

    /**
     * @param InstalledRepositoryInterface $repo
     * @return string
     */
    protected function getPHPCodeSnifferStandardsBasePath(InstalledRepositoryInterface $repo)
    {
        $package = $this->getPHPCodeSnifferPackage($repo);
        $basePath = $this->getInstallPath($package);

        return $basePath . DIRECTORY_SEPARATOR . 'CodeSniffer' . DIRECTORY_SEPARATOR . 'Standards';
    }

    /**
     * @param InstalledRepositoryInterface $repo
     * @return PackageInterface
     */
    protected function getPHPCodeSnifferPackage(InstalledRepositoryInterface $repo)
    {
        $packageKey = 'squizlabs/php_codesniffer';
        $package = $repo->findPackage($packageKey, '*');
        if (!$package) {
            throw new \RuntimeException(sprintf('Package "%s" not installed.', $packageKey));
        }

        return $package;
    }

    /**
     * @param InstalledRepositoryInterface $repo
     * @return string
     */
    protected function getPHPCodeSnifferInstallPath(InstalledRepositoryInterface $repo)
    {
        return $this->getInstallPath($this->getPHPCodeSnifferPackage($repo));
    }
}