package frame

import (
	"errors"
	"fmt"
	"net/http"
	"strings"

	"github.com/gin-gonic/gin"
	"github.com/zhang2092/gohelpers/pkg/token"
)

const (
	authorizationHeaderKey  = "authorization"
	authorizationTypeBearer = "bearer"
	authorizationPayloadKey = "authorization_payload"
)

// AuthJWT creates a gin middleware for authorization
//goland:noinspection GoUnusedExportedFunction
func AuthJWT(tokenMaker token.Maker) gin.HandlerFunc {
	return func(c *gin.Context) {
		authorizationHeader := c.GetHeader(authorizationHeaderKey)

		if len(authorizationHeader) == 0 {
			err := errors.New("authorization header is not provided")
			WrapContext(c).Error(http.StatusUnauthorized, err.Error())
			return
		}

		fields := strings.Fields(authorizationHeader)
		if len(fields) < 2 {
			err := errors.New("invalid authorization header format")
			WrapContext(c).Error(http.StatusUnauthorized, err.Error())
			return
		}

		authorizationType := strings.ToLower(fields[0])
		if authorizationType != authorizationTypeBearer {
			err := fmt.Errorf("unsupported authorization type %s", authorizationType)
			WrapContext(c).Error(http.StatusUnauthorized, err.Error())
			return
		}

		accessToken := fields[1]
		payload, err := tokenMaker.VerifyToken(accessToken)
		if err != nil {
			WrapContext(c).Error(http.StatusUnauthorized, err.Error())
			return
		}

		c.Set(authorizationPayloadKey, payload)
		c.Next()
	}
}