<?php
/**
 * Uninstall Tagloom.
 *
 * @package Tagloom
 */

declare(strict_types=1);

// Abort unless WordPress is actually uninstalling this plugin.
if ( ! defined( 'WP_UNINSTALL_PLUGIN' ) ) {
	exit;
}

/*
 * An escape hatch for a site that wants its data to survive an uninstall.
 *
 * The default is the destructive one — uninstalling takes every table and
 * option — because a plugin that cannot be fully removed is a plugin nobody can
 * trust. What makes it worth an override here is that a template is authored
 * work. A label someone spent an afternoon positioning to the half-millimetre
 * against a physical roll of stock is not recoverable from anything; it is
 * closer to a document than to a setting.
 *
 * Define `TAGLOOM_KEEP_DATA` as true in wp-config.php to keep it. The intended
 * use is troubleshooting: delete and reinstall without redrawing your labels.
 */
if ( defined( 'TAGLOOM_KEEP_DATA' ) && constant( 'TAGLOOM_KEEP_DATA' ) ) {
	return;
}

/**
 * Removes everything Tagloom stored on the current site.
 *
 * A function rather than top-level code so a network can run it once per site;
 * see the loop below it.
 */
function tagloom_uninstall_site(): void {
	global $wpdb;

	/*
	 * Everything Tagloom stored, found by prefix rather than listed.
	 *
	 * Both sweeps below are prefix queries on purpose, and the reason is a defect
	 * this repo has shipped twice: uninstalling SnippetGrove or Crawlune left a table and
	 * roughly twenty options behind, from hand-written lists that had gone stale.
	 * Nothing could see it — a leftover option throws nothing, renders nothing, and
	 * exists only on installs where somebody changed the setting that writes it, so
	 * a default install looks spotless.
	 *
	 * A longer list is the same defect with a later expiry date. Options and tables
	 * are prefixed per product precisely so this can be one query each, and
	 * `UninstallCoverageTest` asserts the two things that keep it complete: every
	 * name the plugin declares carries the prefix, and these sweeps are still here.
	 *
	 * Deliberately self-contained: no autoloader, no plugin classes. Uninstall runs
	 * with only this file loaded, and a fatal here leaves a site with orphaned data
	 * and no way to remove it from the admin. Reading the table names out of the
	 * database rather than out of `Migrator` costs one query and removes that whole
	 * failure mode — including the one where a class_exists() guard quietly skips
	 * the drop and reports success.
	 */

	// phpcs:disable WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching
	// Reason: there is no core API for "every table/option with this prefix", and
	// caching a read taken in order to delete its own results is meaningless. The
	// option deletes below go through delete_option(), so the cache is invalidated.

	$tagloom_tables = $wpdb->get_col(
		$wpdb->prepare(
			'SHOW TABLES LIKE %s',
			$wpdb->esc_like( $wpdb->prefix . 'tagloom_' ) . '%'
		)
	);

	foreach ( (array) $tagloom_tables as $tagloom_table ) {
		// phpcs:ignore WordPress.DB.DirectDatabaseQuery.SchemaChange -- Uninstall is where a plugin is expected to drop its own tables.
		$wpdb->query( $wpdb->prepare( 'DROP TABLE IF EXISTS %i', (string) $tagloom_table ) );
	}

	/*
	 * Transients are options too, under two rows each, so they come out of the same
	 * sweep — the value and its timeout.
	 */
	$tagloom_option_names = $wpdb->get_col(
		$wpdb->prepare(
			'SELECT option_name FROM %i WHERE option_name LIKE %s OR option_name LIKE %s OR option_name LIKE %s',
			$wpdb->options,
			$wpdb->esc_like( 'tagloom_' ) . '%',
			$wpdb->esc_like( '_transient_tagloom_' ) . '%',
			$wpdb->esc_like( '_transient_timeout_tagloom_' ) . '%'
		)
	);

	// phpcs:enable WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching

	/*
	 * Removed through delete_option() rather than one DELETE, so a persistent
	 * object cache is invalidated on the way. A raw DELETE leaves `alloptions`
	 * holding values whose rows are gone, which a later reinstall reads back as
	 * settings nobody set.
	 */
	foreach ( (array) $tagloom_option_names as $tagloom_option_name ) {
		delete_option( (string) $tagloom_option_name );
	}
}

/*
 * On a network, every site — not just the one the network admin happens to be
 * on. Without this loop a network uninstall removed the main site's tables and
 * options and left every other site's behind; ShareCrew and Gloty closed the
 * same gap. get_sites() with 'number' => 0 lifts the default 100-site cap.
 * Tagloom stores nothing network-wide, so there is no separate network pass.
 */
if ( is_multisite() ) {
	$tagloom_site_ids = get_sites(
		[
			'fields' => 'ids',
			'number' => 0,
		]
	);

	foreach ( (array) $tagloom_site_ids as $tagloom_site_id ) {
		switch_to_blog( (int) $tagloom_site_id );
		tagloom_uninstall_site();
		restore_current_blog();
	}
} else {
	tagloom_uninstall_site();
}

/*
 * DELIBERATELY NOT REMOVED: the per-order-item traceability meta.
 *
 * When Tagloom prints a label it stamps the values it printed onto the order
 * item, so the order keeps a permanent record of which batch each unit was
 * filled from. That is a record about goods that physically shipped to a
 * customer. It belongs to the order rather than to the plugin, and for a food,
 * cosmetics or fragrance seller it may be the one thing a regulator asks for.
 *
 * Deleting it because somebody uninstalled a printing tool would destroy
 * evidence they are required to keep. Leaving a few rows of orphaned meta
 * behind is the cheaper mistake by a wide margin.
 *
 * It is also why the sweeps above are scoped to `tagloom_`-prefixed names: the
 * stamp lives on the order item under `_tagloom_printed`, which no prefix query
 * for options or tables can reach. That is deliberate, not an oversight — see
 * `UninstallCoverageTest::test_the_traceability_stamp_is_left_alone()`.
 */