package middleware

import (
	"strings"

	"github.com/gin-gonic/gin"

	"portal-mini-go/internal/pkg/errors"
	"portal-mini-go/internal/pkg/token"
)

const adminIDCtxKey = "admin_id"

// AdminAuth 校验后台请求的 Bearer JWT，校验通过后将 admin_id 注入 context。
func AdminAuth(jwtSecret string) gin.HandlerFunc {
	return func(c *gin.Context) {
		auth := c.GetHeader("Authorization")
		const prefix = "Bearer "
		if !strings.HasPrefix(auth, prefix) {
			c.Error(errors.ErrUnauthorized)
			c.Abort()
			return
		}
		claims, err := token.Parse(jwtSecret, strings.TrimPrefix(auth, prefix))
		if err != nil {
			c.Error(errors.ErrUnauthorized)
			c.Abort()
			return
		}
		c.Set(adminIDCtxKey, claims.AdminID)
		c.Next()
	}
}

// AdminID 从 gin.Context 取出已认证的后台管理员 ID。
func AdminID(c *gin.Context) string {
	if v, ok := c.Get(adminIDCtxKey); ok {
		if s, ok := v.(string); ok {
			return s
		}
	}
	return ""
}