<?php

namespace rbRedirection;

defined( 'ABSPATH' ) || exit;

// phpcs:disable WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- the plugin's own 404 log table, written once per 404 and read only in the admin

/**
 * Addresses that ended in "not found": one row per address, with how often
 * and when it was asked for, so dead links can be fixed with a redirect.
 */
class NotFoundLog {

	public const CLEAN_HOOK = 'rb_redirection_clean_log';

	public static function record( string $request_uri ): void {
		global $wpdb;
		$url = Url::normalize( $request_uri );
		if ( $url === '' || self::ignored( $url ) ) {
			return;
		}
		$now      = current_time( 'mysql', true );
		$referrer = isset( $_SERVER['HTTP_REFERER'] ) ? esc_url_raw( wp_unslash( $_SERVER['HTTP_REFERER'] ) ) : ''; // phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotSanitized
		$agent    = isset( $_SERVER['HTTP_USER_AGENT'] ) ? substr( sanitize_text_field( wp_unslash( $_SERVER['HTTP_USER_AGENT'] ) ), 0, 255 ) : ''; // phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotSanitized
		$table    = Install::log_table();
		// one statement: a new address, or one more hit of a known one
		$wpdb->query( $wpdb->prepare(
			"INSERT INTO %i (url, url_hash, hits, referrer, user_agent, first_seen, last_seen) VALUES (%s, %s, 1, %s, %s, %s, %s)
			 ON DUPLICATE KEY UPDATE hits = hits + 1, last_seen = VALUES(last_seen), referrer = IF(VALUES(referrer) <> '', VALUES(referrer), referrer), user_agent = VALUES(user_agent)",
			$table, $url, Url::hash( $url ), $referrer, $agent, $now, $now
		) );
	}

	/** files browsers and bots ask for on every site: noise in the log */
	private static function ignored( string $url ): bool {
		return (bool) preg_match( '#^/(favicon\.ico|apple-touch-icon[^/]*\.png|robots\.txt|\.well-known/|wp-content/cache/)#', $url )
			// phpcs:ignore WordPress.NamingConventions.PrefixAllGlobals.NonPrefixedHooknameFound -- rb_redirection_ is this plugin's prefix (constants, options, tables, functions and hooks); Plugin Check only guesses rbRedirection from the namespace
			|| (bool) apply_filters( 'rb_redirection_ignore_404', false, $url );
	}

	/** @return array{items: object[], total: int} */
	public static function query( array $args ): array {
		global $wpdb;
		$t      = Install::log_table();
		$like   = empty( $args['search'] ) ? '' : '%' . $wpdb->esc_like( (string) $args['search'] ) . '%';
		$order  = in_array( $args['orderby'] ?? '', array( 'hits', 'last_seen', 'url' ), true ) ? $args['orderby'] : 'last_seen';
		$dir    = ( $args['order'] ?? 'desc' ) === 'asc' ? 'ASC' : 'DESC';
		$per    = max( 1, min( 5000, (int) ( $args['per_page'] ?? 20 ) ) );
		$offset = max( 0, ( (int) ( $args['page'] ?? 1 ) - 1 ) * $per );
		// no search: the empty $like switches the LIKE off; the order column comes from the list above
		$total = (int) $wpdb->get_var( $wpdb->prepare( "SELECT COUNT(*) FROM %i WHERE (%s = '' OR url LIKE %s)", $t, $like, $like ) );
		$items = $wpdb->get_results( $wpdb->prepare(
			"SELECT * FROM %i WHERE (%s = '' OR url LIKE %s)
			 ORDER BY CASE WHEN %s = 'ASC' THEN %i END ASC, CASE WHEN %s = 'DESC' THEN %i END DESC, id DESC LIMIT %d OFFSET %d",
			$t, $like, $like, $dir, $order, $dir, $order, $per, $offset
		) );
		// whether each address has a redirect now
		foreach ( $items as $item ) {
			$item->redirect_id = 0;
			$match             = Redirects::match( (string) $item->url );
			if ( $match ) {
				$item->redirect_id = (int) $match['row']->id;
			}
		}
		return array( 'items' => $items, 'total' => $total );
	}

	public static function delete( array $ids ): int {
		global $wpdb;
		$ids = array_filter( array_map( 'absint', $ids ) );
		if ( ! $ids ) {
			return 0;
		}
		$in = implode( ',', array_fill( 0, count( $ids ), '%d' ) );
		// phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared,WordPress.DB.PreparedSQLPlaceholders.ReplacementsWrongNumber -- $in is only %d placeholders, one per id
		return (int) $wpdb->query( $wpdb->prepare( "DELETE FROM %i WHERE id IN ({$in})", Install::log_table(), ...$ids ) );
	}

	public static function clear(): int {
		global $wpdb;
		return (int) $wpdb->query( $wpdb->prepare( 'DELETE FROM %i', Install::log_table() ) );
	}

	/** daily: forget addresses not seen for "log404Days" days */
	public static function clean(): int {
		global $wpdb;
		$days = (int) Settings::get( 'log404Days' );
		$cut  = gmdate( 'Y-m-d H:i:s', time() - max( 1, $days ) * DAY_IN_SECONDS );
		return (int) $wpdb->query( $wpdb->prepare( 'DELETE FROM %i WHERE last_seen < %s', Install::log_table(), $cut ) );
	}
}