import ipaddr from 'ipaddr.js';

export class IPRestrictionModule {
    private blockedIPs: Set<string> = new Set();
    private blockedCIDRs: any[] = [];

    constructor() {}

    setRules(rules: any[]) {
        this.blockedIPs.clear();
        this.blockedCIDRs = [];
        
        rules.forEach(rule => {
            if (rule.type === 'IP' && rule.enabled) {
                if (rule.config?.ip) {
                    this.blockedIPs.add(rule.config.ip);
                }
                if (rule.config?.cidr) {
                     try {
                        this.blockedCIDRs.push(ipaddr.parseCIDR(rule.config.cidr));
                     } catch (e) {
                         console.error('Invalid CIDR rule', rule.config.cidr);
                     }
                }
            }
        });
    }

    isBlocked(ip: string): boolean {
        // Direct match
        if (this.blockedIPs.has(ip)) return true;
        
        // CIDR match
        if (this.blockedCIDRs.length > 0) {
            try {
                const parsedIP = ipaddr.parse(ip);
                for (const cidr of this.blockedCIDRs) {
                    // ipaddr.js match method signature issue with TS union types
                    // Cast to any to bypass strict union check or use specific type guard
                    if ((parsedIP as any).match(cidr)) return true;
                }
            } catch (e) {
                // Invalid IP in request
            }
        }
        return false;
    }
}