package request

import (
	"errors"
	"github.com/dgrijalva/jwt-go"
	"net/http"
	"strings"
)

// Errors
var (
	ErrNoTokenInRequest = errors.New("no token present in request")
)

// Try to find the token in an http.Request.
// This method will call ParseMultipartForm if there's no token in the header.
// Currently, it looks in the Authorization header as well as
// looking for an 'access_token' request parameter in req.Form.
func ParseFromRequest(req *http.Request, keyFunc jwt.Keyfunc) (token *jwt.Token, err error) {
	return ParseFromRequestWithClaims(req, keyFunc, &jwt.MapClaims{})
}

func ParseFromRequestWithClaims(req *http.Request, keyFunc jwt.Keyfunc, claims jwt.Claims) (token *jwt.Token, err error) {
	// Look for an Authorization header
	if ah := req.Header.Get("Authorization"); ah != "" {
		// Should be a bearer token
		if len(ah) > 6 && strings.ToUpper(ah[0:7]) == "BEARER " {
			return jwt.ParseWithClaims(ah[7:], keyFunc, claims)
		}
	}

	// Look for "access_token" parameter
	req.ParseMultipartForm(10e6)
	if tokStr := req.Form.Get("access_token"); tokStr != "" {
		return jwt.ParseWithClaims(tokStr, keyFunc, claims)
	}

	return nil, ErrNoTokenInRequest
}