<?php
/**
 * Removes everything the plugin stored, unless the user asked to keep it.
 *
 * Almost all of that is per site: the settings, the events table, the cron
 * events, the post meta and the transients each live in one site's tables. So
 * the work is written once, in `acid_aeo_uninstall_site()`, and a multisite
 * install runs it against every site in the network.
 *
 * Two things are not per site, and are done once, by the main site: the files
 * in the webroot (one network shares one `ABSPATH`, so deleting them on every
 * hop would be the same delete repeated) and the user meta (`wp_usermeta` is a
 * network-wide table, and the keys carry no site prefix).
 *
 * @package AcidStudios\AEO
 */

defined( 'WP_UNINSTALL_PLUGIN' ) || exit;

/**
 * Removes one site's stored state.
 *
 * @param bool $shared Whether this call also owns the state the network shares:
 *                     the generated files in the webroot and the user meta. It
 *                     follows that a main site with "keep my data" ticked keeps
 *                     the shared state too, which is the reading of that box
 *                     somebody would expect from the site they set it on.
 * @return void
 */
function acid_aeo_uninstall_site( bool $shared ): void {
	global $wpdb;

	$settings = get_option( 'acid_aeo_settings', [] );

	if ( ! is_array( $settings ) ) {
		$settings = [];
	}

	// The stored rewrite table can still hold this plugin's rules, and a rule
	// that outlives the code behind it resolves to the home page instead of a
	// 404. Deleting the option makes WordPress regenerate the table on the next
	// request, from the rules the plugins that are still installed add. This
	// happens whether or not the settings are being kept: the rules are
	// WordPress' data, not ours.
	delete_option( 'rewrite_rules' );

	if ( ! empty( $settings['general']['keep_data'] ) ) {
		return;
	}

	foreach ( [ 'acid_aeo_settings', 'acid_aeo_cache_ver', 'acid_aeo_db_version', 'acid_aeo_flush_needed', 'acid_aeo_indexnow_queue', 'acid_aeo_indexnow_log', 'acid_aeo_static_files_active', 'acid_aeo_loop_ver', 'acid_aeo_sitemap_url' ] as $option ) {
		delete_option( $option );
	}

	wp_clear_scheduled_hook( 'acid_aeo_daily' );
	wp_clear_scheduled_hook( 'acid_aeo_indexnow_flush' );
	wp_clear_scheduled_hook( 'acid_aeo_static_write' );

	// The events table is created by the plugin, so it is dropped with it. One
	// per site: `$wpdb->prefix` follows the switch.
	$wpdb->query( "DROP TABLE IF EXISTS {$wpdb->prefix}acid_aeo_events" ); // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching, WordPress.DB.DirectDatabaseQuery.SchemaChange, WordPress.DB.PreparedSQL.InterpolatedNotPrepared

	foreach ( [ '_acid_aeo_summary', '_acid_aeo_faq', '_acid_aeo_exclude', '_acid_aeo_noai', '_acid_aeo_schema_type', '_acid_aeo_license', '_acid_aeo_credit', '_acid_aeo_creator', '_acid_aeo_hide_updated' ] as $post_meta ) {
		delete_metadata( 'post', 0, $post_meta, '', true );
	}

	// Transients are versioned, so they are matched by prefix rather than by
	// name. `$wpdb->options` follows the switch too.
	$wpdb->query( // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching
		$wpdb->prepare(
			"DELETE FROM {$wpdb->options} WHERE option_name LIKE %s OR option_name LIKE %s",
			$wpdb->esc_like( '_transient_acid_aeo_' ) . '%',
			$wpdb->esc_like( '_transient_timeout_acid_aeo_' ) . '%'
		)
	);

	if ( ! $shared ) {
		return;
	}

	// `wp_usermeta` is one table for the whole network and these keys carry no
	// site prefix, so this is a single global delete, not a per-site one.
	foreach ( [ 'acid_aeo_job_title', 'acid_aeo_same_as', 'acid_aeo_knows_about', 'acid_aeo_alumni_of', 'acid_aeo_notice_dismissed' ] as $user_meta ) {
		delete_metadata( 'user', 0, $user_meta, '', true );
	}

	// Physical files are only removed when the plugin wrote them. The text
	// files sign themselves with a comment line; ai-context.json cannot carry a
	// comment, so its `instructions.generator` field is the signature. Both are
	// matched as substrings, so a file written by an older version is still
	// recognised. robots.txt is deliberately absent: the plugin never writes it.
	// Where the files were written, which is not always where WordPress lives:
	// on a site given its own directory the webroot is the one above `ABSPATH`.
	// The class the module writes through is loaded rather than copied, so the
	// delete cannot drift from the write.
	require_once __DIR__ . '/includes/Support/Filesystem.php';

	$webroot = \AcidStudios\AEO\Support\Filesystem::webroot();

	foreach ( [ 'llms.txt', 'llms-full.txt', 'humans.txt', 'ai.txt', 'ai-context.json', '.well-known/security.txt' ] as $file ) {
		$path = $webroot . $file;

		if ( ! is_file( $path ) || ! is_readable( $path ) ) {
			continue;
		}

		$contents = file_get_contents( $path ); // phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents

		if ( ! is_string( $contents ) ) {
			continue;
		}

		foreach ( [ 'generated by Acid AEO', '"generator": "Acid AEO' ] as $marker ) {
			if ( false !== strpos( $contents, $marker ) ) {
				wp_delete_file( $path );
				break;
			}
		}
	}
}

if ( ! is_multisite() ) {
	acid_aeo_uninstall_site( true );

	return;
}

$acid_aeo_main_site_id = (int) get_main_site_id();

foreach ( get_sites(
	[
		'fields' => 'ids',
		'number' => 0,
	]
) as $acid_aeo_site_id ) {
	switch_to_blog( (int) $acid_aeo_site_id );

	// The `finally` unwinds the switch whatever the body did. A site whose
	// tables are half gone can make `DROP TABLE` or `delete_metadata()` throw,
	// and a switch left on the stack would point the rest of the uninstall —
	// and every site after this one — at the wrong database tables.
	try {
		acid_aeo_uninstall_site( (int) $acid_aeo_site_id === $acid_aeo_main_site_id );
	} finally {
		restore_current_blog();
	}
}