package jwt

import (
	"errors"

	"zestack.dev/slim"
)

type AuthConfig struct {
	Skipper     func(c slim.Context) bool
	Finder      Finder
	Anonymously bool
	Claims      func(c slim.Context, token string, claims *Claims) error
}

func (config AuthConfig) ToMiddleware() slim.MiddlewareFunc {
	if config.Finder == nil {
		config.Finder = DefaultFinder
	}
	return func(c slim.Context, next slim.HandlerFunc) error {
		if config.Skipper != nil && config.Skipper(c) {
			return next(c)
		}
		token := config.Finder(c)
		if token == "" {
			if config.Anonymously {
				return next(c)
			}
			return ErrTokenNotFound
		}
		claims, err := Verify(token)
		if errors.Is(err, ErrTokenExpired) {
			c.SetHeader("X-Token-Expired", "true")
		} else if err != nil {
			return err
		}
		if config.Claims != nil {
			err = config.Claims(c, token, claims)
			if err != nil {
				return err
			}
		}
		if c.Written() {
			return nil
		}
		c.Set("jwt:token", token)
		c.Set("jwt:claims", claims)
		return next(c)
	}
}

func Auth(c AuthConfig) slim.MiddlewareFunc {
	return c.ToMiddleware()
}