package utils

import (
	"os"
	"time"

	"github.com/golang-jwt/jwt/v5"
)

var jwtSecret = []byte(os.Getenv("JWT_SECRET"))

type Claims struct {
	UUID string `json:"uuid"`
	jwt.RegisteredClaims
}

// GenerateJWT generates a new JWT token for a user
func GenerateJWT(uuid string) (string, error) {
	// Set expiration time (24 hours from now)
	expirationTime := time.Now().Add(24 * time.Hour)

	// Create claims
	claims := &Claims{
		UUID: uuid,
		RegisteredClaims: jwt.RegisteredClaims{
			ExpiresAt: jwt.NewNumericDate(expirationTime),
			IssuedAt:  jwt.NewNumericDate(time.Now()),
		},
	}

	// Create token with claims
	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)

	// Generate encoded token
	tokenString, err := token.SignedString(jwtSecret)
	if err != nil {
		return "", err
	}

	return tokenString, nil
}

// ParseJWT parses and validates a JWT token
func ParseJWT(tokenString string) (*Claims, error) {
	claims := &Claims{}

	// Parse token
	token, err := jwt.ParseWithClaims(tokenString, claims, func(token *jwt.Token) (interface{}, error) {
		return jwtSecret, nil
	})

	if err != nil {
		return nil, err
	}

	// Check if token is valid
	if !token.Valid {
		return nil, jwt.ErrTokenMalformed
	}

	return claims, nil
}