/*
   GoToSocial
   Copyright (C) 2021 GoToSocial Authors admin@gotosocial.org

   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU Affero General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU Affero General Public License for more details.

   You should have received a copy of the GNU Affero General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

package federation

import (
	"context"
	"net/http"
	"net/url"

	"github.com/go-fed/activity/pub"
	"github.com/go-fed/activity/streams/vocab"
	"github.com/sirupsen/logrus"
	"github.com/superseriousbusiness/gotosocial/internal/config"
	"github.com/superseriousbusiness/gotosocial/internal/db"
)

// Commoner implements the go-fed common behavior interface
type Commoner struct {
	db     db.DB
	log    *logrus.Logger
	config *config.Config
}

/*
	GOFED COMMON BEHAVIOR INTERFACE
	Contains functions required for both the Social API and Federating Protocol.
	It is passed to the library as a dependency injection from the client
	application.
*/

// AuthenticateGetInbox delegates the authentication of a GET to an
// inbox.
//
// Always called, regardless whether the Federated Protocol or Social
// API is enabled.
//
// If an error is returned, it is passed back to the caller of
// GetInbox. In this case, the implementation must not write a
// response to the ResponseWriter as is expected that the client will
// do so when handling the error. The 'authenticated' is ignored.
//
// If no error is returned, but authentication or authorization fails,
// then authenticated must be false and error nil. It is expected that
// the implementation handles writing to the ResponseWriter in this
// case.
//
// Finally, if the authentication and authorization succeeds, then
// authenticated must be true and error nil. The request will continue
// to be processed.
func (c *Commoner) AuthenticateGetInbox(ctx context.Context, w http.ResponseWriter, r *http.Request) (context.Context, bool, error) {
	// TODO
	// use context.WithValue() and context.Value() to set and get values through here
	return nil, false, nil
}

// AuthenticateGetOutbox delegates the authentication of a GET to an
// outbox.
//
// Always called, regardless whether the Federated Protocol or Social
// API is enabled.
//
// If an error is returned, it is passed back to the caller of
// GetOutbox. In this case, the implementation must not write a
// response to the ResponseWriter as is expected that the client will
// do so when handling the error. The 'authenticated' is ignored.
//
// If no error is returned, but authentication or authorization fails,
// then authenticated must be false and error nil. It is expected that
// the implementation handles writing to the ResponseWriter in this
// case.
//
// Finally, if the authentication and authorization succeeds, then
// authenticated must be true and error nil. The request will continue
// to be processed.
func (c *Commoner) AuthenticateGetOutbox(ctx context.Context, w http.ResponseWriter, r *http.Request) (context.Context, bool, error) {
	// TODO
	return nil, false, nil
}

// GetOutbox returns the OrderedCollection inbox of the actor for this
// context. It is up to the implementation to provide the correct
// collection for the kind of authorization given in the request.
//
// AuthenticateGetOutbox will be called prior to this.
//
// Always called, regardless whether the Federated Protocol or Social
// API is enabled.
func (c *Commoner) GetOutbox(ctx context.Context, r *http.Request) (vocab.ActivityStreamsOrderedCollectionPage, error) {
	// TODO
	return nil, nil
}

// NewTransport returns a new Transport on behalf of a specific actor.
//
// The actorBoxIRI will be either the inbox or outbox of an actor who is
// attempting to do the dereferencing or delivery. Any authentication
// scheme applied on the request must be based on this actor. The
// request must contain some sort of credential of the user, such as a
// HTTP Signature.
//
// The gofedAgent passed in should be used by the Transport
// implementation in the User-Agent, as well as the application-specific
// user agent string. The gofedAgent will indicate this library's use as
// well as the library's version number.
//
// Any server-wide rate-limiting that needs to occur should happen in a
// Transport implementation. This factory function allows this to be
// created, so peer servers are not DOS'd.
//
// Any retry logic should also be handled by the Transport
// implementation.
//
// Note that the library will not maintain a long-lived pointer to the
// returned Transport so that any private credentials are able to be
// garbage collected.
func (c *Commoner) NewTransport(ctx context.Context, actorBoxIRI *url.URL, gofedAgent string) (pub.Transport, error) {
	// TODO
	// prefs := []httpsig.Algorithm{httpsig.RSA_SHA256}
	// digestPref := httpsig.DigestSha256
	// getHeadersToSign := []string{httpsig.RequestTarget, "Date"}
	// postHeadersToSign := []string{httpsig.RequestTarget, "Date", "Digest"}
	// // Using github.com/go-fed/httpsig for HTTP Signatures:
	// getSigner, _, err := httpsig.NewSigner(prefs, digestPref, getHeadersToSign, httpsig.Signature)
	// if err != nil {
	// 	return nil, err
	// }
	// postSigner, _, err := httpsig.NewSigner(prefs, digestPref, postHeadersToSign, httpsig.Signature)
	// if err != nil {
	// 	return nil, err
	// }
	// pubKeyId, privKey, err := s.getKeysForActorBoxIRI(actorBoxIRI)
	// client := &http.Client{
	// 	Timeout: time.Second * 30,
	// }
	// t := pub.NewHttpSigTransport(
	// 	client,
	// 	f.config.Host,
	// 	&Clock{},
	// 	getSigner,
	// 	postSigner,
	// 	pubKeyId,
	// 	privKey)

	return nil, nil

}