<?php

namespace Kaliop\eZMigrationBundle\Command;

use Kaliop\eZMigrationBundle\API\ConfigResolverInterface;
use Kaliop\eZMigrationBundle\API\MigrationGeneratorInterface;
use Kaliop\eZMigrationBundle\API\MatcherInterface;
use Kaliop\eZMigrationBundle\API\EnumerableMatcherInterface;
use Kaliop\eZMigrationBundle\API\Event\MigrationGeneratedEvent;
use Kaliop\eZMigrationBundle\Core\MigrationService;
use Symfony\Component\Console\Input\InputArgument;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Input\InputOption;
use Symfony\Component\Console\Output\OutputInterface;
use Symfony\Component\EventDispatcher\EventDispatcherInterface;
use Symfony\Component\HttpFoundation\File\Exception\FileException;
use Symfony\Component\HttpKernel\Kernel;
use Symfony\Component\Yaml\Yaml;
use Twig\Environment;

/**
 * @todo allow passing in more context options, esp. for content/generate migrations
 */
class GenerateCommand extends AbstractCommand
{
    const DIR_CREATE_PERMISSIONS = 0755;

    protected static $defaultName = 'kaliop:migration:generate';

    private $availableMigrationFormats = array('yml', 'php', 'sql', 'json');
    private $availableModes = array('create', 'update', 'delete');
    private $availableTypes = array('content', 'content_type', 'content_type_group', 'language', 'object_state', 'object_state_group', 'role', 'section', 'generic', 'db', 'php', '...');
    private $thisBundle = 'eZMigrationBundle';

    protected $eventName = 'ez_migration.migration_generated';
    protected $eventDispatcher;
    protected $twig;
    protected $configResolver;

    public function __construct(MigrationService $migrationService, EventDispatcherInterface $eventDispatcher,
        Environment $twig, ConfigResolverInterface $configResolver)
    {
        parent::__construct($migrationService);
        $this->eventDispatcher = $eventDispatcher;
        $this->twig = $twig;
        $this->configResolver = $configResolver;
    }

    /**
     * Configure the console command
     */
    protected function configure()
    {
        $this
            ->setDescription('Generate a blank migration definition file.')
            ->addOption('format', null, InputOption::VALUE_REQUIRED, 'The format of migration file to generate (' . implode(', ', $this->availableMigrationFormats) . ')', 'yml')
            ->addOption('type', null, InputOption::VALUE_REQUIRED, 'The type of migration to generate (' . implode(', ', $this->availableTypes) . ')', '')
            ->addOption('mode', null, InputOption::VALUE_REQUIRED, 'The mode of the migration (' . implode(', ', $this->availableModes) . ')', 'create')
            ->addOption('match-type', null, InputOption::VALUE_REQUIRED, 'The type of identifier used to find the entity to generate the migration for', null)
            ->addOption('match-value', null, InputOption::VALUE_REQUIRED, 'The identifier value used to find the entity to generate the migration for. Can have many values separated by commas', null)
            ->addOption('match-except', null, InputOption::VALUE_NONE, 'Used to match all entities except the ones satisfying the match-value condition', null)
            ->addOption('lang', 'l', InputOption::VALUE_REQUIRED, 'The language of the migration (eng-GB, ger-DE, ...). If null, the default language of the current siteaccess is used')
            ->addOption('dbserver', null, InputOption::VALUE_REQUIRED, 'The type of the database server the sql migration is for, when type=db (mysql, postgresql, ...)', 'mysql')
            ->addOption('admin-login', 'a', InputOption::VALUE_REQUIRED, "Login of admin account used whenever elevated privileges are needed (user id 14 used by default)")
            ->addOption('list-types', null, InputOption::VALUE_NONE, 'Use this option to list all available migration types and their match conditions')
            ->addArgument('bundle', InputArgument::OPTIONAL, 'The bundle to generate the migration definition file in. eg.: AcmeMigrationBundle')
            ->addArgument('name', InputArgument::OPTIONAL, 'The migration name (will be prefixed with current date)', null)
            ->setHelp(<<<EOT
The <info>kaliop:migration:generate</info> command generates a skeleton migration definition file:

    <info>php ezpublish/console kaliop:migration:generate</info>

You can optionally specify the file type to generate with <info>--format</info>, bundle name where the migration definition should be created as well a name for the migration:

    <info>php ezpublish/console kaliop:migration:generate --format=json bundleName migrationName</info>

For SQL type migration you can optionally specify the database server type the migration is for with <info>--dbserver</info>:

    <info>php ezpublish/console kaliop:migration:generate --format=sql</info>

For content/content_type/language/object_state/role/section migrations you need to specify the entity that you want to generate the migration for:

    <info>php ezpublish/console kaliop:migration:generate --type=content --match-type=content_id --match-value=10,14 --lang=all</info>

For role type migration you will receive a yaml file with the current role definition. You must define ALL the policies
you wish for the role. Any not defined will be removed. Example for updating an existing role:

    <info>php ezpublish/console kaliop:migration:generate --type=role --mode=update --match-type=identifier --match-value=Anonymous</info>

For freeform php migrations, you will receive a php class definition

    <info>php ezpublish/console kaliop:migration:generate --format=php classname</info>

To list all available migration types for generation, as well as the corresponding match-types, run:

    <info>php ezpublish/console ka:mig:gen --list-types</info>

Note that you can pass in a custom directory path instead of a bundle name, but, if you do, you will have to use the <info>--path</info>
option when you run the <info>migrate</info> command.
EOT
            );
    }

    /**
     * Run the command and display the results.
     *
     * @param InputInterface $input
     * @param OutputInterface $output
     * @return int 0 if everything went fine, or an error code
     * @throws \InvalidArgumentException When an unsupported file type is selected
     *
     * @todo for type=db, we could fold 'dbserver' option into 'mode'
     */
    public function execute(InputInterface $input, OutputInterface $output)
    {
        $this->setOutput($output);
        $this->setVerbosity($output->getVerbosity());

        if ($input->getOption('list-types')) {
            $this->listAvailableTypes($output);
            return 0;
        }

        $bundleName = $input->getArgument('bundle');
        $name = $input->getArgument('name');
        $fileType = $input->getOption('format');
        $migrationType = $input->getOption('type');
        $matchType = $input->getOption('match-type');
        $matchValue = $input->getOption('match-value');
        $matchExcept = $input->getOption('match-except');
        $mode = $input->getOption('mode');
        $dbServer = $input->getOption('dbserver');

        if ($bundleName == $this->thisBundle) {
            throw new \InvalidArgumentException("It is not allowed to create migrations in bundle '$bundleName'");
        }

        // be kind to lazy users
        if ($migrationType == '') {
            if ($fileType == 'sql') {
                $migrationType = 'db';
            } elseif ($fileType == 'php') {
                $migrationType = 'php';
            } else {
                $migrationType = 'generic';
            }
        }

        if (!in_array($fileType, $this->availableMigrationFormats)) {
            throw new \InvalidArgumentException('Unsupported migration file format ' . $fileType);
        }

        if (!in_array($mode, $this->availableModes)) {
            throw new \InvalidArgumentException('Unsupported migration mode ' . $mode);
        }

        $migrationDirectory = $this->getMigrationDirectory($bundleName);

        if (!is_dir($migrationDirectory)) {
            $output->writeln(sprintf(
                "Migrations directory <info>%s</info> does not exist. I will create it now....",
                $migrationDirectory
            ));

            if (mkdir($migrationDirectory, self::DIR_CREATE_PERMISSIONS, true)) {
                $output->writeln(sprintf(
                    "Migrations directory <info>%s</info> has been created",
                    $migrationDirectory
                ));
            } else {
                throw new FileException(sprintf(
                    "Failed to create migrations directory %s.",
                    $migrationDirectory
                ));
            }
        }

        // allow to generate migrations for many entities
        if (strpos($matchValue, ',') !== false ) {
            $matchValue = explode(',', $matchValue);
        }

        $parameters = array(
            'type' => $migrationType,
            'mode' => $mode,
            'matchType' => $matchType,
            'matchValue' => $matchValue,
            'matchExcept' => $matchExcept,
            'dbserver' => $dbServer,
            /// @todo move these 2 params out of here, pass the context as template parameter instead
            'lang' => $input->getOption('lang'),
            'adminLogin' => $input->getOption('admin-login')
            /// @todo should we allow users to specify this ?
            //'forceSigchildEnabled' => null
        );

        $date = date('YmdHis');

        switch ($fileType) {
            case 'sql':
                /// @todo this logic should come from the DefinitionParser, really
                if ($name != '') {
                    $name = '_' . ltrim($name, '_');
                }
                $fileName = $date . '_' . $dbServer . $name . '.sql';
                break;

            case 'php':
                /// @todo this logic should come from the DefinitionParser, really
                $className = ltrim($name, '_');
                if ($className == '') {
                    $className = 'Migration';
                }
                // Make sure that php class names are unique, not only migration definition file names
                $existingMigrations = count(glob($migrationDirectory . '/*_' . $className . '*.php'));
                if ($existingMigrations) {
                    $className = $className . sprintf('%03d', $existingMigrations + 1);
                }
                $parameters = array_merge($parameters, array(
                    'class_name' => $className
                ));
                $fileName = $date . '_' . $className . '.php';
                break;

            default:
                if ($name == '') {
                    $name = 'placeholder';
                }
                $fileName = $date . '_' . $name . '.' . $fileType;
        }

        $filePath = $migrationDirectory . '/' . $fileName;

        $warning = $this->generateMigrationFile($migrationType, $mode, $fileType, $filePath, $parameters);

        $output->writeln(sprintf("Generated new migration file: <info>%s</info>", $filePath));

        if ($warning != '') {
            $output->writeln("<comment>$warning</comment>");
        }

        return 0;
    }

    /**
     * Generates a migration definition file.
     * @todo allow non-filesystem storage (delegate saving to a service, just as we do for loading)
     *
     * @param string $migrationType The type of migration to generate
     * @param string $migrationMode
     * @param string $fileType The type of migration file to generate
     * @param string $filePath filename to file to generate (full path)
     * @param array $parameters passed on to twig
     * @return string A warning message in case file generation was OK but there was something weird
     * @throws \Exception
     */
    protected function generateMigrationFile($migrationType, $migrationMode, $fileType, $filePath, array $parameters = array())
    {
        $warning = '';

        switch ($migrationType) {
            case 'db':
            case 'generic':
            case 'php':
                // Generate migration file by template
                $template = $migrationType . 'Migration.' . $fileType . '.twig';
                $templatePath = $this->getApplication()->getKernel()->getBundle($this->thisBundle)->getPath() . '/Resources/views/MigrationTemplate/';
                if (!is_file($templatePath . $template)) {
                    throw new \Exception("The combination of migration type '$migrationType' is not supported with format '$fileType'");
                }
                $code = $this->twig->render('@' . preg_replace('/Bundle$/', '', $this->thisBundle) . '/MigrationTemplate/' . $template, $parameters);

                // allow event handlers to replace data
                $event = new MigrationGeneratedEvent($migrationType, $migrationMode, $fileType, $code, $filePath);
                $this->eventDispatcher->dispatch($event, $this->eventName);
                $code = $event->getData();
                $filePath = $event->getFile();

                break;

            default:
                // Generate migration file by executor
                $executors = $this->getGeneratingExecutors();
                if (!in_array($migrationType, $executors)) {
                    throw new \Exception("It is not possible to generate a migration of type '$migrationType': executor not found or not a generator");
                }
                /** @var MigrationGeneratorInterface $executor */
                $executor = $this->getMigrationService()->getExecutor($migrationType);

                $context = $this->migrationContextFromParameters($parameters);

                $matchCondition = array($parameters['matchType'] => $parameters['matchValue']);
                if ($parameters['matchExcept']) {
                    $matchCondition = array(MatcherInterface::MATCH_NOT => $matchCondition);
                }
                $data = $executor->generateMigration($matchCondition, $migrationMode, $context);

                // allow event handlers to replace data
                $event = new MigrationGeneratedEvent($migrationType, $migrationMode, $fileType, $data, $filePath, $matchCondition, $context);
                $this->eventDispatcher->dispatch($event, $this->eventName);
                $data = $event->getData();
                $filePath = $event->getFile();

                if (!is_array($data) || !count($data)) {
                    $warning = 'Note: the generated migration is empty';
                }

                switch ($fileType) {
                    case 'yml':
                    case 'yaml':
                        /// @todo use Yaml::DUMP_EMPTY_ARRAY_AS_SEQUENCE option if it is supported
                        $code = Yaml::dump($data, 5);
                        break;
                    case 'json':
                        $code = json_encode($data, JSON_PRETTY_PRINT);
                        break;
                    default:
                        throw new \Exception("The combination of migration type '$migrationType' is not supported with format '$fileType'");
                }
        }

        file_put_contents($filePath, $code);

        return $warning;
    }

    protected function listAvailableTypes(OutputInterface $output)
    {
        $output->writeln('Specific migration types available for generation (besides sql,php, generic):');
        foreach ($this->getGeneratingExecutors() as $executorType) {
            $output->writeln($executorType);
            /** @var MigrationGeneratorInterface $executor */
            $executor = $this->getMigrationService()->getExecutor($executorType);
            if ($executor instanceof EnumerableMatcherInterface) {
                $conditions = $executor->listAllowedConditions();
                $conditions = array_diff($conditions, array('and', 'or', 'not'));
                $output->writeln("  corresponding match types:\n    - " . implode("\n    - ", $conditions));
            }
        }
    }

    /**
     * @param string|null $bundleName a bundle name or filesystem path to a directory
     * @return string
     */
    protected function getMigrationDirectory($bundleName)
    {
        if (!$bundleName) {
            return $this->getApplication()->getKernel()->getProjectDir() . '/src/' . $this->configResolver->getParameter('ez_migration_bundle.version_directory');
        }

        // Allow direct usage of a directory path instead of a bundle name
        if (strpos($bundleName, '/') !== false && is_dir($bundleName)) {
            return rtrim($bundleName, '/');
        }

        $activeBundles = array();
        foreach ($this->getApplication()->getKernel()->getBundles() as $bundle) {
            $activeBundles[] = $bundle->getName();
        }
        asort($activeBundles);
        if (!in_array($bundleName, $activeBundles)) {
            throw new \InvalidArgumentException("Bundle '$bundleName' does not exist or it is not enabled. Try with one of:\n" . implode(', ', $activeBundles));
        }

        $bundle = $this->getApplication()->getKernel()->getBundle($bundleName);
        $migrationDirectory = $bundle->getPath() . '/' . $this->configResolver->getParameter('ez_migration_bundle.version_directory');

        return $migrationDirectory;
    }

    /**
     * @todo move somewhere else. Maybe to the MigrationService itself ?
     * @return string[]
     */
    protected function getGeneratingExecutors()
    {
        $migrationService = $this->getMigrationService();
        $executors = $migrationService->listExecutors();
        foreach($executors as $key => $name) {
            $executor = $migrationService->getExecutor($name);
            if (!$executor instanceof MigrationGeneratorInterface) {
                unset($executors[$key]);
            }
        }
        return $executors;
    }

    /**
     * @see MigrationService::migrationContextFromParameters
     * @param array $parameters these come directly from cli options
     * @return array
     */
    protected function migrationContextFromParameters(array $parameters)
    {
        $context = array();

        if (isset($parameters['lang']) && $parameters['lang'] != '') {
            $context['defaultLanguageCode'] = $parameters['lang'];
        }
        if (isset($parameters['adminLogin']) && $parameters['adminLogin'] != '') {
            $context['adminUserLogin'] = $parameters['adminLogin'];
        }
        if (isset($parameters['forceSigchildEnabled']) && $parameters['forceSigchildEnabled'] !== null)
        {
            $context['forceSigchildEnabled'] = $parameters['forceSigchildEnabled'];
        }

        return $context;
    }
}