<?php
/**
 * Runs when the plugin is deleted from the Plugins screen (or `wp plugin uninstall operanse-agent`), after
 * deactivation. Removes everything the agent put on the site and nothing else:
 *
 *  - every `operanse_agent*` option (settings, credentials, spool location, recent errors/changes, custom forms,
 *    host state, dead letters, the database spool's drop counter) and every `operanse_*` transient (the update
 *    check, the inbound-denial counter);
 *  - the two tables the agent creates: `{prefix}operanse_spool` (tier-4 buffer) and `{prefix}operanse_nonces`
 *    (inbound replay protection);
 *  - the file spool directory named in the spool-location option — **only** that directory, and only when every
 *    file in it is a spool file or a guard file the agent wrote, so a directory that was ever shared with
 *    something else is left alone;
 *  - the agent's scheduled events (deactivation already cleared them; repeated here for a plugin deleted without
 *    deactivating cleanly).
 *
 * Nothing is sent over the network: the API has no "unpair" call, and the site's record on Operanse is the
 * customer's to remove from the dashboard. The credentials die with the option, so nothing signed can be sent
 * from this site again. The read-only boundary (invariant 1) is untouched: this deletes the agent's own data.
 */

declare(strict_types=1);

if ( ! defined( 'WP_UNINSTALL_PLUGIN' ) ) {
	exit;
}

global $wpdb;

// The spool directories, read before the option that names them is gone: the one in use, and a retired
// outside-the-web-root directory whose events had not all been moved yet (ADR-072 §8 Q3).
$operanse_spool_dirs = array();
$operanse_location   = get_option( 'operanse_agent_spool_location', array() );
if ( is_array( $operanse_location ) && isset( $operanse_location['dir'] ) && is_string( $operanse_location['dir'] ) && ( $operanse_location['tier'] ?? '' ) !== 'database' ) {
	$operanse_spool_dirs[] = $operanse_location['dir'];
}
if ( is_array( $operanse_location ) && isset( $operanse_location['legacy_dir'] ) && is_string( $operanse_location['legacy_dir'] ) ) {
	$operanse_spool_dirs[] = $operanse_location['legacy_dir'];
}

// Scheduled events.
foreach ( array( 'operanse_collect', 'operanse_flush', 'operanse_poll' ) as $operanse_hook ) {
	wp_clear_scheduled_hook( $operanse_hook );
}
foreach ( array( 'scheduled', 'activation', 'pairing', 'manual' ) as $operanse_trigger ) {
	wp_clear_scheduled_hook( 'operanse_discover', array( $operanse_trigger ) );
}

// Options and transients, by prefix, so a key added by a later build is not missed. The underscore is escaped:
// in LIKE it is a wildcard. `wp_cache_delete( 'alloptions' )` follows because two of these are autoloaded.
$wpdb->query( $wpdb->prepare( "DELETE FROM {$wpdb->options} WHERE option_name LIKE %s", $wpdb->esc_like( 'operanse_agent' ) . '%' ) ); // phpcs:ignore WordPress.DB
$wpdb->query( $wpdb->prepare( "DELETE FROM {$wpdb->options} WHERE option_name LIKE %s OR option_name LIKE %s", $wpdb->esc_like( '_transient_operanse_' ) . '%', $wpdb->esc_like( '_transient_timeout_operanse_' ) . '%' ) ); // phpcs:ignore WordPress.DB
$wpdb->query( $wpdb->prepare( "DELETE FROM {$wpdb->options} WHERE option_name LIKE %s OR option_name LIKE %s", $wpdb->esc_like( '_site_transient_operanse_' ) . '%', $wpdb->esc_like( '_site_transient_timeout_operanse_' ) . '%' ) ); // phpcs:ignore WordPress.DB
wp_cache_delete( 'alloptions', 'options' );
foreach ( array( 'operanse_agent_update_check', 'operanse_inbound_denied' ) as $operanse_transient ) {
	delete_transient( $operanse_transient ); // the object-cache copy, on a site with a persistent cache
}

// The agent's own tables.
$wpdb->query( "DROP TABLE IF EXISTS `{$wpdb->prefix}operanse_spool`" ); // phpcs:ignore WordPress.DB
$wpdb->query( "DROP TABLE IF EXISTS `{$wpdb->prefix}operanse_nonces`" ); // phpcs:ignore WordPress.DB

// The file spool: only the directories the option named, only if they hold nothing but what the agent wrote.
foreach ( $operanse_spool_dirs as $operanse_spool_dir ) {
	if ( $operanse_spool_dir === '' || ! is_dir( $operanse_spool_dir ) ) {
		continue;
	}
	$operanse_entries = scandir( $operanse_spool_dir );
	$operanse_only_ours = is_array( $operanse_entries );
	if ( is_array( $operanse_entries ) ) {
		foreach ( $operanse_entries as $operanse_name ) {
			if ( $operanse_name === '.' || $operanse_name === '..' ) {
				continue;
			}
			$operanse_is_ours = in_array( $operanse_name, array( '.htaccess', 'index.html', 'web.config', 'dropped.json' ), true )
				|| (bool) preg_match( '/^(critical|normal|sampled)(\.active|-\d{14}-[0-9a-f]{6}\.ndjson)(\.moving)?$/', $operanse_name )
				|| (bool) preg_match( '/^probe-[0-9a-f]{16}\.ndjson$/', $operanse_name );
			if ( ! $operanse_is_ours || is_dir( $operanse_spool_dir . '/' . $operanse_name ) ) {
				$operanse_only_ours = false;
				break;
			}
		}
	}
	if ( $operanse_only_ours ) {
		foreach ( (array) $operanse_entries as $operanse_name ) {
			if ( $operanse_name !== '.' && $operanse_name !== '..' ) {
				@unlink( $operanse_spool_dir . '/' . $operanse_name ); // phpcs:ignore WordPress.PHP.NoSilencedErrors, WordPress.WP.AlternativeFunctions
			}
		}
		@rmdir( $operanse_spool_dir ); // phpcs:ignore WordPress.PHP.NoSilencedErrors, WordPress.WP.AlternativeFunctions
		// And the parent the agent made for it, if that is now empty: the plugin's uploads folder or its older names.
		if ( in_array( basename( dirname( $operanse_spool_dir ) ), array( 'operanse-agent', 'operanse-private', 'operanse-data' ), true ) ) {
			@rmdir( dirname( $operanse_spool_dir ) ); // phpcs:ignore WordPress.PHP.NoSilencedErrors, WordPress.WP.AlternativeFunctions
		}
	}
}