<?php
/**
 * ChatWeb Debug Logger Class
 *
 * Logs all API calls for debugging purposes
 */

// Prevent direct access
if (!defined('ABSPATH')) {
    exit;
}

class Aiflab_Chatweb_Debug_Logger {

    /**
     * Table name
     */
    private static $table_name = 'aiflab_chatweb_api_logs';

    /**
     * Get full table name with prefix
     */
    public static function get_table_name() {
        global $wpdb;
        return $wpdb->prefix . self::$table_name;
    }

    /**
     * Create database table
     */
    public static function create_table() {
        global $wpdb;
        
        $table_name = self::get_table_name();
        $charset_collate = $wpdb->get_charset_collate();

        $sql = "CREATE TABLE IF NOT EXISTS {$table_name} (
            id BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
            created_at DATETIME NOT NULL,
            method VARCHAR(10) NOT NULL,
            url TEXT NOT NULL,
            request_headers TEXT,
            request_body LONGTEXT,
            response_status INT,
            response_headers TEXT,
            response_body LONGTEXT,
            duration_ms INT,
            PRIMARY KEY (id),
            KEY created_at (created_at)
        ) {$charset_collate};";

        require_once(ABSPATH . 'wp-admin/includes/upgrade.php');
        dbDelta($sql);
    }

    /**
     * Log an API request/response
     *
     * @param array $data Log data
     * @return int|false Insert ID or false on failure
     */
    public static function log($data) {
        global $wpdb;
        
        $table_name = self::get_table_name();
        
        // Prepare data
        $insert_data = array(
            'created_at' => current_time('mysql'),
            'method' => isset($data['method']) ? strtoupper($data['method']) : 'GET',
            'url' => isset($data['url']) ? $data['url'] : '',
            'request_headers' => isset($data['request_headers']) ? (is_array($data['request_headers']) ? wp_json_encode($data['request_headers']) : $data['request_headers']) : null,
            'request_body' => isset($data['request_body']) ? (is_array($data['request_body']) ? wp_json_encode($data['request_body']) : $data['request_body']) : null,
            'response_status' => isset($data['response_status']) ? intval($data['response_status']) : null,
            'response_headers' => isset($data['response_headers']) ? (is_array($data['response_headers']) ? wp_json_encode($data['response_headers']) : $data['response_headers']) : null,
            'response_body' => isset($data['response_body']) ? (is_string($data['response_body']) ? $data['response_body'] : wp_json_encode($data['response_body'])) : null,
            'duration_ms' => isset($data['duration_ms']) ? intval($data['duration_ms']) : null
        );
        
        $result = $wpdb->insert($table_name, $insert_data);
        
        if ($result === false) {
            return false;
        }
        
        return $wpdb->insert_id;
    }

    /**
     * Get logs for the last N days
     *
     * @param int $days Number of days to fetch (default: 3)
     * @param int $limit Max number of records (default: 500)
     * @param string $search Search term for URL
     * @param string $status_filter Filter by status (success, error, all)
     * @return array Array of log entries
     */
    public static function get_logs($days = 3, $limit = 500, $search = '', $status_filter = 'all') {
        global $wpdb;
        
        $table_name = self::get_table_name();
        
        // Calculate date threshold
        $date_threshold = gmdate('Y-m-d H:i:s', strtotime("-{$days} days"));
        
        // Build query — $table_name is derived from $wpdb->prefix, not user input.
        // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared
        $query = "SELECT * FROM {$table_name} WHERE created_at >= %s";
        $params = array($date_threshold);

        // Add search filter
        if (!empty($search)) {
            $query .= " AND url LIKE %s";
            $params[] = '%' . $wpdb->esc_like($search) . '%';
        }

        // Add status filter
        if ($status_filter === 'success') {
            $query .= " AND response_status >= 200 AND response_status < 300";
        } elseif ($status_filter === 'error') {
            $query .= " AND (response_status IS NULL OR response_status < 200 OR response_status >= 300)";
        }

        // Order by newest first
        $query .= " ORDER BY created_at DESC LIMIT %d";
        $params[] = $limit;

        // Prepare and execute query — $query uses only $wpdb->prefix-based table name and standard placeholders.
        // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
        $prepared_query = $wpdb->prepare($query, $params);
        // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
        $results = $wpdb->get_results($prepared_query, ARRAY_A);
        
        return $results ? $results : array();
    }

    /**
     * Get a single log entry by ID
     *
     * @param int $id Log ID
     * @return array|null Log entry or null
     */
    public static function get_log($id) {
        global $wpdb;
        
        $table_name = self::get_table_name();
        
        // phpcs:disable WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- $table_name is derived from $wpdb->prefix, not user input.
        $query = $wpdb->prepare(
            "SELECT * FROM {$table_name} WHERE id = %d",
            $id
        );
        // phpcs:enable WordPress.DB.PreparedSQL.InterpolatedNotPrepared

        // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared -- $query is the return value of $wpdb->prepare() above.
        return $wpdb->get_row($query, ARRAY_A);
    }

    /**
     * Drop the debug logger table
     */
    public static function drop_table() {
        global $wpdb;
        $table_name = self::get_table_name();
        // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared,WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- $table_name is $wpdb->prefix based; table names cannot use prepare() parameters.
        $wpdb->query("DROP TABLE IF EXISTS {$table_name}");
    }

    /**
     * Clear all logs
     *
     * @return int|false Number of rows deleted or false on error
     */
    public static function clear_logs() {
        global $wpdb;
        
        $table_name = self::get_table_name();
        
        // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared,WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- $table_name is $wpdb->prefix based; TRUNCATE does not support prepare() parameters.
        return $wpdb->query("TRUNCATE TABLE {$table_name}");
    }

    /**
     * Clear logs older than N days
     *
     * @param int $days Number of days to keep
     * @return int|false Number of rows deleted or false on error
     */
    public static function clear_old_logs($days = 7) {
        global $wpdb;
        
        $table_name = self::get_table_name();
        $date_threshold = gmdate('Y-m-d H:i:s', strtotime("-{$days} days"));
        
        return $wpdb->query(
            $wpdb->prepare(
                // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- $table_name is derived from $wpdb->prefix, not user input.
                "DELETE FROM {$table_name} WHERE created_at < %s",
                $date_threshold
            )
        );
    }

    /**
     * Get log statistics
     *
     * @param int $days Number of days to analyze
     * @return array Statistics
     */
    public static function get_stats($days = 3) {
        global $wpdb;
        
        $table_name = self::get_table_name();
        $date_threshold = gmdate('Y-m-d H:i:s', strtotime("-{$days} days"));
        
        // phpcs:disable WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- $table_name is derived from $wpdb->prefix, not user input.
        $stats = $wpdb->get_row(
            $wpdb->prepare(
                "SELECT
                    COUNT(*) as total,
                    SUM(CASE WHEN response_status >= 200 AND response_status < 300 THEN 1 ELSE 0 END) as success_count,
                    SUM(CASE WHEN response_status IS NULL OR response_status < 200 OR response_status >= 300 THEN 1 ELSE 0 END) as error_count,
                    AVG(duration_ms) as avg_duration
                FROM {$table_name}
                WHERE created_at >= %s",
                $date_threshold
            ),
            ARRAY_A
        );
        // phpcs:enable WordPress.DB.PreparedSQL.InterpolatedNotPrepared
        
        return $stats ? $stats : array(
            'total' => 0,
            'success_count' => 0,
            'error_count' => 0,
            'avg_duration' => 0
        );
    }
}