<?php
/**
 * Export step 1: moves the password out of job state, normalises the options, names the archive and starts it.
 *
 * Options: include {db, uploads, plugins, themes, mu_plugins, others} (all true by default), excludes string[],
 * replace array<old,new>, password ?string, storage string ('local'), label ?string. Job::create has already moved the
 * password to Mench_Migrate_Secrets and left options.encrypted in its place.
 *
 * @package Mench_Migrate
 */

defined( 'ABSPATH' ) || exit;

class Mench_Migrate_Step_Export_Init extends Mench_Migrate_Step_Export_Base {

	public const INCLUDE_KEYS = [ 'db', 'uploads', 'plugins', 'themes', 'mu_plugins', 'others' ];

	public function label(): string {
		return __( 'Preparing the export', 'mench-migrate' );
	}

	public function run( Mench_Migrate_Job $job, float $deadline ): Mench_Migrate_Step_Result {
		// On a network the prefix matches every subsite's tables: refuse rather than export a mix (the Multisite add-on's job).
		if ( (bool) apply_filters( 'mench_migrate_is_multisite', is_multisite() ) ) {
			throw new Mench_Migrate_Exception( 'multisite_unsupported', 'export-init' );
		}
		$raw     = (array) ( $job->data['options'] ?? [] );
		$options = self::normalise( $raw );
		$storage = Mench_Migrate_Storages::get( $options['storage'] )->id();
		if ( $options['encrypted'] && ! Mench_Migrate_Crypto::available() ) {
			throw new Mench_Migrate_Archive_Exception( 'crypto_unavailable', 'export-init' );
		}
		// initiator_login and the options an add-on set through mench_migrate_job_options (a schedule id ...) stay next to
		// the core ones; any other key a caller sent is dropped, so a plain export cannot pose as an add-on's job.
		$keep                 = array_flip( array_merge( [ 'initiator_login' ], array_map( 'strval', (array) ( $job->data['addon_option_keys'] ?? [] ) ) ) );
		$options              = $options + array_intersect_key( array_diff_key( $raw, array_flip( [ 'password', 'encrypted' ] ) ), $keep );
		$job->data['options'] = $options;

		// The name is saved before the archive is opened, so a re-run after a crash reuses it and leaves no stray .part.
		if ( empty( $job->data['archive'] ) ) {
			if ( 'cancelled' === Mench_Migrate_Job::disk_status( $job->id ) ) {
				return Mench_Migrate_Step_Result::done(); // The runner sees the cancel and merges nothing.
			}
			$job->data['archive'] = self::filtered_archive_name( $job );
			$job->save();
		}
		$list = self::list_path( $job );
		wp_delete_file( $list );
		self::remove_db_dir( $job );

		$writer = Mench_Migrate_Archive_Writer::open( self::part_path( $job ), self::password( $job ), self::index_path( $job ) );
		$state  = $writer->state();
		unset( $writer );
		$job->log( 'info', 'Writing ' . $job->data['archive'] . ( $options['encrypted'] ? ' (encrypted)' : '' ) . '.' );

		return Mench_Migrate_Step_Result::done( [
			'options'       => $options,
			'archive'       => $job->data['archive'],
			'storage'       => $storage,
			'writer'        => $state,
			'skipped_files' => 0,
		] );
	}

	/** Fills defaults and drops anything malformed (a stray password key included). */
	public static function normalise( array $o ): array {
		$include = (array) ( $o['include'] ?? [] );
		$inc     = [];
		foreach ( self::INCLUDE_KEYS as $k ) {
			$inc[ $k ] = array_key_exists( $k, $include ) ? (bool) filter_var( $include[ $k ], FILTER_VALIDATE_BOOLEAN ) : true;
		}
		$excludes = [];
		foreach ( (array) ( $o['excludes'] ?? [] ) as $g ) {
			if ( is_string( $g ) && '' !== trim( $g ) ) {
				$excludes[] = trim( $g );
			}
		}
		$replace = [];
		foreach ( (array) ( $o['replace'] ?? [] ) as $old => $new ) {
			$old = (string) $old; // A numeric-string key arrives as an int.
			if ( '' !== $old && is_scalar( $new ) ) {
				$replace[ $old ] = (string) $new;
			}
		}
		$storage = isset( $o['storage'] ) && is_string( $o['storage'] ) && '' !== $o['storage'] ? $o['storage'] : 'local';
		$label   = isset( $o['label'] ) && is_string( $o['label'] ) && '' !== trim( $o['label'] ) ? sanitize_text_field( $o['label'] ) : null;
		return [
			'encrypted' => ! empty( $o['encrypted'] ), // Set by Job::create when it stashed a password.
			'include'   => $inc,
			'excludes'  => array_values( array_unique( $excludes ) ),
			'replace'   => $replace,
			'storage'   => $storage,
			'label'     => $label,
		];
	}

	/**
	 * The default name passed through mench_migrate_archive_name( string $name, Mench_Migrate_Job $job ) (1.1.0), so an
	 * add-on can tag it (the Schedules add-on adds -sched-<id>). The result is used only when it is still a valid .mmig
	 * name that keeps the default's random suffix; anything else falls back to the default.
	 */
	public static function filtered_archive_name( Mench_Migrate_Job $job ): string {
		$name     = self::archive_name();
		$suffix   = substr( $name, -21, 16 ); // <16 random>.mmig
		$filtered = apply_filters( 'mench_migrate_archive_name', $name, $job );
		if ( is_string( $filtered ) && $filtered !== $name && Mench_Migrate_Storage_Local::valid_name( $filtered ) && '.mmig' === substr( $filtered, -5 ) && str_contains( $filtered, $suffix ) ) {
			return $filtered;
		}
		return $name;
	}

	/** <sanitized host>-<Ymd-His>-<16 random>.mmig; the suffix keeps the name unguessable where backups/ is web-reachable. */
	public static function archive_name(): string {
		return self::archive_host() . '-' . gmdate( 'Ymd-His' ) . '-' . Mench_Migrate_Paths::random_suffix( 16 ) . '.mmig';
	}

	/** 1.1.0: the sanitized host every archive name of this site starts with ('site' when there is none). */
	public static function archive_host(): string {
		$host = strtolower( (string) wp_parse_url( home_url(), PHP_URL_HOST ) );
		$host = trim( (string) preg_replace( '/[^a-z0-9.-]+/', '-', $host ), '.-' );
		return '' === $host ? 'site' : $host;
	}
}