<?php
/**
 * Fired when the plugin is uninstalled (Delete, from the Plugins screen).
 *
 * Only when settings.delete_on_uninstall is true (the default) does it
 * best-effort revoke the connected Google refresh token (not on a site whose
 * address changed since it connected, which may be a copy) and remove every
 * Tagsmith option and transient and the Clarity snapshot table. When it
 * is false, the settings and the Google connection are kept for a
 * reinstall, and the connection's access is NOT revoked: it stays active at
 * Google until the person removes it at myaccount.google.com/permissions.
 * Scheduled events are always removed. On multisite, this runs once per
 * site.
 *
 * It only deletes options whose names start with tagsmith_, so it never
 * touches the options of any other plugin.
 *
 * @package Tagsmith
 */

declare(strict_types=1);

defined( 'WP_UNINSTALL_PLUGIN' ) || exit;

if ( ! defined( 'TAGSMITH_DIR' ) ) {
	define( 'TAGSMITH_DIR', plugin_dir_path( __FILE__ ) );
}

require_once TAGSMITH_DIR . 'src/autoload.php';

// Everything below runs inside a closure so the file can be require()'d more
// than once in the same process (as tests do) without redeclaring anything
// in the global namespace.
( function (): void {
	/**
	 * Best-effort revokes the connected Google refresh token. Never throws
	 * and never blocks uninstall on failure.
	 *
	 * Not on a site whose address changed since it connected: that may be a
	 * copy (staging, a migration) holding the live site's token, and revoking
	 * it would end the live site's access. Its token is removed with the
	 * rest of the data below, and the access stays active at Google until it
	 * is removed at myaccount.google.com/permissions.
	 */
	$revoke_token = static function (): void {
		try {
			$connection = new \Tagsmith\Auth\Connection( new \Tagsmith\Auth\TokenStore() );
			$refresh    = $connection->refresh_token();

			if ( null === $refresh || '' === $refresh || $connection->home_url_changed() ) {
				return;
			}

			wp_remote_post(
				'https://oauth2.googleapis.com/revoke',
				array(
					'timeout' => 5,
					'body'    => array( 'token' => $refresh ),
				)
			);
		} catch ( \Throwable $e ) {
			unset( $e ); // Best effort only.
		}
	};

	/**
	 * Deletes every option whose name starts with the given prefix, by name.
	 * The names come from a prepared lookup and each one is removed with
	 * delete_option(), which keeps WordPress's option cache correct on its
	 * own. A direct DELETE would leave stale options in the cache, and the
	 * only fix is to flush the whole object cache, which empties it for the
	 * entire site (on some hosts, for every site).
	 *
	 * The prefix is checked again in PHP, which is always case-sensitive.
	 * Most database collations (and SQLite's LIKE) compare ASCII
	 * case-insensitively, so the lookup also returns names that differ from
	 * the prefix only in case (Tagsmith_Foo for tagsmith_), which are not
	 * ours to delete.
	 *
	 * @param string $prefix Literal start of the option names.
	 */
	$delete_options_starting_with = static function ( string $prefix ): void {
		global $wpdb;

		// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- only looks the names up; delete_option() below deletes and invalidates the cache.
		$names = $wpdb->get_col(
			$wpdb->prepare(
				"SELECT option_name FROM {$wpdb->options} WHERE option_name LIKE %s",
				$wpdb->esc_like( $prefix ) . '%'
			)
		);

		foreach ( $names as $name ) {
			if ( ! str_starts_with( $name, $prefix ) ) {
				continue;
			}

			delete_option( $name );
		}
	};

	/**
	 * Deletes every Tagsmith option and transient for the current site
	 * (or, inside a switch_to_blog(), the current blog).
	 */
	$delete_tagsmith_data = static function () use ( $revoke_token, $delete_options_starting_with ): void {
		$revoke_token();

		// The Clarity snapshot table (created only once a Data Export token
		// was saved; dropping a missing table is a no-op).
		( new \Tagsmith\Clarity\SnapshotStore() )->drop();

		// Today's Clarity calls per project, a network option on multisite
		// (on a single site the wildcard below catches it too).
		delete_site_option( \Tagsmith\Clarity\ClaritySync::CALLS_OPTION );

		// Every option this plugin has ever added starts with tagsmith_,
		// so a single prefix lookup catches all of them without needing a
		// name list to stay in sync.
		$delete_options_starting_with( 'tagsmith_' );

		$delete_options_starting_with( '_transient_tagsmith_' );
		$delete_options_starting_with( '_transient_timeout_tagsmith_' );

		// With a persistent object cache, transients live in the cache and
		// not in the options table, so the lookups above find none of them.
		// The ones with a fixed name are removed by name: the access token
		// (it holds a credential), and the quota, back-off, lock and error
		// flags, which would otherwise outlast the plugin by up to an hour.
		// The rest have a hash or a one-time value in their names (cached
		// reports, the sign-in hand-over, a failing-page-views flag), so
		// they cannot be listed; they expire by themselves.
		$fixed_transients = array(
			\Tagsmith\Auth\Connection::ACCESS_TRANSIENT,
			\Tagsmith\Reports\QuotaGuard::QUOTA_LOW,
			\Tagsmith\Rest\ReportsController::FORCE_LOCK,
			\Tagsmith\Rest\SystemController::CACHE_CLEAR_LOCK,
			\Tagsmith\Admin\PostsColumn::ERROR_TRANSIENT,
		);

		// One back-off per API.
		foreach ( \Tagsmith\Reports\QuotaGuard::APIS as $api ) {
			$fixed_transients[] = \Tagsmith\Reports\QuotaGuard::backoff_key( $api );
		}

		foreach ( $fixed_transients as $transient ) {
			delete_transient( $transient );
		}
	};

	/**
	 * Deletes the current site's data, but only when it has opted in via
	 * settings.delete_on_uninstall (default true).
	 */
	$maybe_delete_current_site = static function () use ( $delete_tagsmith_data ): void {
		$settings = new \Tagsmith\Settings();

		if ( ! (bool) $settings->get( 'delete_on_uninstall' ) ) {
			return;
		}

		$delete_tagsmith_data();
	};

	/**
	 * Per-site cleanup: pending posts-column warm-up and Clarity sync events
	 * always go (their handlers are being deleted with the plugin); stored
	 * data only when the site opted in.
	 */
	$uninstall_current_site = static function () use ( $maybe_delete_current_site ): void {
		wp_unschedule_hook( 'tagsmith_warm_posts_column' );
		wp_unschedule_hook( \Tagsmith\Clarity\ClaritySync::CRON_HOOK );
		$maybe_delete_current_site();
	};

	if ( is_multisite() ) {
		$site_ids = get_sites(
			array(
				'fields' => 'ids',
				'number' => 0,
			)
		);

		foreach ( $site_ids as $site_id ) {
			switch_to_blog( (int) $site_id );
			$uninstall_current_site();
			restore_current_blog();
		}
	} else {
		$uninstall_current_site();
	}
} )();