<?php
/**
 * Logger class for sync operations
 */

if (!defined('ABSPATH')) {
    exit;
}

class MLS_Logger {

    /**
     * Log levels
     */
    const DEBUG = 'debug';
    const INFO = 'info';
    const WARNING = 'warning';
    const ERROR = 'error';

    /**
     * Database instance
     */
    private $db;

    /**
     * Current sync state ID
     */
    private $sync_state_id = null;

    /**
     * Whether to also write to WP debug log
     */
    private $write_to_debug_log = true;

    /**
     * Constructor
     *
     * @param MLS_DB $db Database instance
     */
    public function __construct(MLS_DB $db) {
        $this->db = $db;
        $this->write_to_debug_log = defined('WP_DEBUG') && WP_DEBUG;
    }

    /**
     * Set current sync state ID for associating logs
     *
     * @param int|null $sync_state_id
     */
    public function set_sync_state($sync_state_id) {
        $this->sync_state_id = $sync_state_id;
    }

    /**
     * Log a message
     *
     * @param string $level Log level
     * @param string $message Message
     * @param array $context Additional context
     */
    public function log($level, $message, $context = array()) {
        global $wpdb;

        // Insert into database
        $wpdb->insert(
            $this->db->sync_log_table(),
            array(
                'sync_state_id' => $this->sync_state_id,
                'level' => $level,
                'message' => $message,
                'context' => !empty($context) ? wp_json_encode($context) : null,
                'created_at' => current_time('mysql'),
            ),
            array('%d', '%s', '%s', '%s', '%s')
        );

        // Also write to WP debug log if enabled
        if ($this->write_to_debug_log) {
            $log_message = sprintf(
                '[MLS] [%s] %s',
                strtoupper($level),
                $message
            );
            if (!empty($context)) {
                $log_message .= ' | Context: ' . wp_json_encode($context);
            }
            error_log($log_message);
        }
    }

    /**
     * Debug log
     *
     * @param string $message
     * @param array $context
     */
    public function debug($message, $context = array()) {
        $this->log(self::DEBUG, $message, $context);
    }

    /**
     * Info log
     *
     * @param string $message
     * @param array $context
     */
    public function info($message, $context = array()) {
        $this->log(self::INFO, $message, $context);
    }

    /**
     * Warning log
     *
     * @param string $message
     * @param array $context
     */
    public function warning($message, $context = array()) {
        $this->log(self::WARNING, $message, $context);
    }

    /**
     * Error log
     *
     * @param string $message
     * @param array $context
     */
    public function error($message, $context = array()) {
        $this->log(self::ERROR, $message, $context);
    }

    /**
     * Get recent logs
     *
     * @param int $limit Number of logs to retrieve
     * @param string|null $level Filter by level
     * @param int|null $sync_state_id Filter by sync state
     * @return array
     */
    public function get_logs($limit = 100, $level = null, $sync_state_id = null) {
        global $wpdb;

        $where = array('1=1');
        $values = array();

        if ($level) {
            $where[] = 'level = %s';
            $values[] = $level;
        }

        if ($sync_state_id) {
            $where[] = 'sync_state_id = %d';
            $values[] = $sync_state_id;
        }

        $where_sql = implode(' AND ', $where);
        $values[] = $limit;

        $sql = "SELECT * FROM {$this->db->sync_log_table()}
                WHERE {$where_sql}
                ORDER BY created_at DESC
                LIMIT %d";

        if (!empty($values)) {
            $sql = $wpdb->prepare($sql, $values);
        }

        return $wpdb->get_results($sql);
    }

    /**
     * Clear old logs
     *
     * @param int $days_to_keep Keep logs from last N days
     * @return int Number of deleted rows
     */
    public function clear_old_logs($days_to_keep = 30) {
        global $wpdb;

        $cutoff = gmdate('Y-m-d H:i:s', strtotime("-{$days_to_keep} days"));

        return $wpdb->query(
            $wpdb->prepare(
                "DELETE FROM {$this->db->sync_log_table()} WHERE created_at < %s",
                $cutoff
            )
        );
    }

    /**
     * Clear all logs
     *
     * @return bool
     */
    public function clear_all() {
        global $wpdb;
        return false !== $wpdb->query("TRUNCATE TABLE {$this->db->sync_log_table()}");
    }
}