package com.mailserver.util;

import io.jsonwebtoken.Claims;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.security.Keys;
import javax.crypto.SecretKey;
import java.nio.charset.StandardCharsets;
import java.util.Date;

public class JwtUtils {

    private static final long EXPIRATION_MS = 1000L * 60 * 60 * 24; // 24 часа

    private final SecretKey signingKey;

    public JwtUtils(String secret) {
        this.signingKey = Keys.hmacShaKeyFor(secret.getBytes(StandardCharsets.UTF_8));
    }

    public String generateToken(String email) {
        Date now = new Date();
        Date expiry = new Date(now.getTime() + EXPIRATION_MS);

        return Jwts.builder()
                .subject(email)
                .issuedAt(now)
                .expiration(expiry)
                .signWith(signingKey)
                .compact();
    }

    public String getEmailFromToken(String token) {
        Claims claims = Jwts.parser()
                .verifyWith(signingKey)
                .build()
                .parseSignedClaims(token)
                .getPayload();
        return claims.getSubject();
    }

    public boolean isValidToken(String token) {
        try {
            Jwts.parser()
                    .verifyWith(signingKey)
                    .build()
                    .parseSignedClaims(token);
            return true;
        } catch (Exception e) {
            return false;
        }
    }
}