package cc.mrbird.febs.gateway.enhance.auth;

import cc.mrbird.febs.gateway.enhance.entity.RouteUser;
import io.jsonwebtoken.Claims;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;

import java.io.Serializable;
import java.util.Base64;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;

/**
 * @author MrBird
 */
@Component
public class JwtTokenHelper implements Serializable {

    private static final long serialVersionUID = 1579222883969867182L;

    @Value("${febs.gateway.jwt.secret}")
    private String secret;

    @Value("${febs.gateway.jwt.expiration}")
    private String expirationTime;

    public Claims getAllClaimsFromToken(String token) {
        return Jwts.parser()
                .setSigningKey(Base64.getEncoder().encodeToString(secret.getBytes()))
                .parseClaimsJws(token)
                .getBody();
    }

    public String getUsernameFromToken(String token) {
        return getAllClaimsFromToken(token).getSubject();
    }

    public Date getExpirationDateFromToken(String token) {
        return getAllClaimsFromToken(token).getExpiration();
    }

    private Boolean isTokenExpired(String token) {
        final Date expiration = getExpirationDateFromToken(token);
        return expiration.before(new Date());
    }

    public String generateToken(RouteUser routeUser) {
        Map<String, Object> claims = new HashMap<>(1);
        claims.put("permission", routeUser.getRoles());
        return doGenerateToken(claims, routeUser.getUsername());
    }

    private String doGenerateToken(Map<String, Object> claims, String username) {
        long expirationTimeLong = Long.parseLong(expirationTime);

        final Date createdDate = new Date();
        final Date expirationDate = new Date(createdDate.getTime() + expirationTimeLong * 1000);
        return Jwts.builder()
                .setClaims(claims)
                .setSubject(username)
                .setIssuedAt(createdDate)
                .setExpiration(expirationDate)
                .signWith(SignatureAlgorithm.HS512, Base64.getEncoder().encodeToString(secret.getBytes()))
                .compact();
    }

    public Boolean validateToken(String token) {
        return !isTokenExpired(token);
    }
}