package slurm

import "net/http"

// TokenAuthTransport implements http.RoundTripper and injects
// X-SLURM-USER-NAME and X-SLURM-USER-TOKEN headers into every request.
type TokenAuthTransport struct {
	UserName string
	Token    string

	// Base is the underlying RoundTripper. If nil, http.DefaultTransport is used.
	Base http.RoundTripper
}

// RoundTrip executes a single HTTP request, adding Slurm authentication headers.
func (t *TokenAuthTransport) RoundTrip(req *http.Request) (*http.Response, error) {
	req2 := cloneRequest(req)
	req2.Header.Set("X-SLURM-USER-NAME", t.UserName)
	req2.Header.Set("X-SLURM-USER-TOKEN", t.Token)
	return t.transport().RoundTrip(req2)
}

// Client returns a new http.Client that uses this TokenAuthTransport.
func (t *TokenAuthTransport) Client() *http.Client {
	return &http.Client{Transport: t}
}

func (t *TokenAuthTransport) transport() http.RoundTripper {
	if t.Base != nil {
		return t.Base
	}
	return http.DefaultTransport
}

// cloneRequest creates a shallow copy of the request with a deep copy of the headers.
func cloneRequest(req *http.Request) *http.Request {
	r := req.Clone(req.Context())
	return r
}