// internal/middleware/auth.go
package middleware

import (
	"net/http"
	"strings"

	"github.com/gin-gonic/gin"
	"github.com/golang-jwt/jwt/v4"
)

type Claims struct {
	UserID uint `json:"user_id"`
	jwt.RegisteredClaims
}

func AuthMiddleware(jwtSecret string) gin.HandlerFunc {
	return func(c *gin.Context) {
		authHeader := c.GetHeader("Authorization")
		if authHeader == "" {
			c.JSON(http.StatusUnauthorized, gin.H{"error": "Authorization header is required"})
			c.Abort()
			return
		}

		tokenString := strings.TrimPrefix(authHeader, "Bearer ")
		if tokenString == authHeader {
			c.JSON(http.StatusUnauthorized, gin.H{"error": "Bearer token is required"})
			c.Abort()
			return
		}

		claims := &Claims{}

		token, err := jwt.ParseWithClaims(tokenString, claims, func(t *jwt.Token) (interface{}, error) {
			return []byte(jwtSecret), nil
		})

		if err != nil || !token.Valid {
			c.JSON(http.StatusUnauthorized, gin.H{"error": "Invalid token"})
			c.Abort()
			return
		}

		c.Set("userID", claims.ID) // 从token中解析出的用户ID
		c.Next()
	}
}