<?php
declare(strict_types=1);

namespace WPDesk\Migrations;

use Psr\Log\LoggerInterface;
use WPDesk\Migrations\Finder\GlobFinder;
use WPDesk\Migrations\Version\AlphabeticalComparator;
use WPDesk\Migrations\Version\Comparator;
use WPDesk\Migrations\Version\Version;
use WPDesk\Migrations\Version\WpdbMigrationFactory;

class WpdbMigrator implements Migrator {

	/** @var \wpdb */
	private $wpdb;

	/** @var MigrationsRepository */
	private $migrations_repository;

	/** @var Comparator */
	private $comparator;

	/** @var LoggerInterface */
	private $logger;

	/** @var string */
	private $option_name;

	/** @param string[] $migration_directories */
	public static function from_directories( array $migration_directories, string $option_name ): self {
		global $wpdb;
		$logger = new WpdbLogger( $option_name . '_log' );

		return new self(
			$wpdb,
			$option_name,
			new FilesystemMigrationsRepository(
				$migration_directories,
				new GlobFinder(),
				new WpdbMigrationFactory(
					$wpdb,
					$logger
				),
				new AlphabeticalComparator()
			),
			new AlphabeticalComparator(),
			$logger
		);
	}

	/** @param class-string<AbstractMigration>[] $migration_class_names */
	public static function from_classes( array $migration_class_names, string $option_name ): self {
		global $wpdb;
		$logger = new WpdbLogger( $option_name . '_log' );

		return new self(
			$wpdb,
			$option_name,
			new ArrayMigrationsRepository(
				$migration_class_names,
				new WpdbMigrationFactory(
					$wpdb,
					$logger
				),
				new AlphabeticalComparator()
			),
			new AlphabeticalComparator(),
			$logger
		);
	}

	public function __construct(
		\wpdb $wpdb,
		string $option_name,
		MigrationsRepository $migrations_repository,
		Comparator $comparator,
		LoggerInterface $logger
	) {
		$this->wpdb                  = $wpdb;
		$this->option_name           = $option_name;
		$this->migrations_repository = $migrations_repository;
		$this->comparator            = $comparator;
		$this->logger                = $logger;
	}

	private function get_current_version(): Version {
		return new Version( get_option( $this->option_name, '' ) );
	}

	private function needs_migration(): bool {
		$migrations     = $this->migrations_repository->get_migrations();
		$last_migration = end( $migrations );
		if ( $last_migration === false ) {
			return false;
		}
		if ( $this->comparator->compare( $last_migration->get_version(), $this->get_current_version() ) ) {
			return true;
		}
		return false;
	}

	public function migrate(): void {
		require_once ABSPATH . 'wp-admin/includes/upgrade.php';

		if ( ! $this->needs_migration() ) {
			return;
		}

		$this->logger->info( 'DB update start' );

		try {
			$this->do_migrate();
		} catch ( \Throwable $e ) {
			// @phpstan-ignore-next-line
			$error_msg = sprintf( 'Error while upgrading a database: %s', $this->wpdb->last_error );
			$this->logger->error( $error_msg );
			trigger_error( esc_html( $error_msg ), E_USER_WARNING ); // phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_trigger_error
		}

		$this->logger->info( 'DB update finished' );
	}

	private function do_migrate(): void {
		$current_version = $this->get_current_version();
		foreach ( $this->migrations_repository->get_migrations() as $migration ) {
			if (
				$this->comparator->compare(
					$migration->get_version(),
					$this->get_current_version()
				) > 0
			) {

				$this->logger->info( sprintf( 'DB update %s:%s', $current_version, $migration->get_version() ) );

				$success = $migration->get_migration()->up();

				if ( $success ) {
					$this->logger->info( sprintf( 'DB update %s:%s -> ', $current_version, $migration->get_version() ) . 'OK' );
					update_option( $this->option_name, (string) $migration->get_version(), true );
				} else {
					throw new \RuntimeException();
				}
			}
		}
	}
}