1 files changed, 73 insertions, 0 deletions
diff --git a/internal/federation/dereferencing/dereferencer.go b/internal/federation/dereferencing/dereferencer.go
new file mode 100644
index 000000000..03b90569a
--- /dev/null
+++ b/internal/federation/dereferencing/dereferencer.go
@@ -0,0 +1,73 @@
+/*
+   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 dereferencing
+
+import (
+	"net/url"
+	"sync"
+
+	"github.com/sirupsen/logrus"
+	"github.com/superseriousbusiness/gotosocial/internal/ap"
+	"github.com/superseriousbusiness/gotosocial/internal/config"
+	"github.com/superseriousbusiness/gotosocial/internal/db"
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+	"github.com/superseriousbusiness/gotosocial/internal/media"
+	"github.com/superseriousbusiness/gotosocial/internal/transport"
+	"github.com/superseriousbusiness/gotosocial/internal/typeutils"
+)
+
+// Dereferencer wraps logic and functionality for doing dereferencing of remote accounts, statuses, etc, from federated instances.
+type Dereferencer interface {
+	GetRemoteAccount(username string, remoteAccountID *url.URL, refresh bool) (*gtsmodel.Account, bool, error)
+	EnrichRemoteAccount(username string, account *gtsmodel.Account) (*gtsmodel.Account, error)
+
+	GetRemoteStatus(username string, remoteStatusID *url.URL, refresh bool) (*gtsmodel.Status, ap.Statusable, bool, error)
+	EnrichRemoteStatus(username string, status *gtsmodel.Status) (*gtsmodel.Status, error)
+
+	GetRemoteInstance(username string, remoteInstanceURI *url.URL) (*gtsmodel.Instance, error)
+
+	DereferenceAnnounce(announce *gtsmodel.Status, requestingUsername string) error
+	DereferenceThread(username string, statusIRI *url.URL) error
+
+	Handshaking(username string, remoteAccountID *url.URL) bool
+}
+
+type deref struct {
+	log                 *logrus.Logger
+	db                  db.DB
+	typeConverter       typeutils.TypeConverter
+	transportController transport.Controller
+	mediaHandler        media.Handler
+	config              *config.Config
+	handshakes          map[string][]*url.URL
+	handshakeSync       *sync.Mutex // mutex to lock/unlock when checking or updating the handshakes map
+}
+
+// NewDereferencer returns a Dereferencer initialized with the given parameters.
+func NewDereferencer(config *config.Config, db db.DB, typeConverter typeutils.TypeConverter, transportController transport.Controller, mediaHandler media.Handler, log *logrus.Logger) Dereferencer {
+	return &deref{
+		log:                 log,
+		db:                  db,
+		typeConverter:       typeConverter,
+		transportController: transportController,
+		mediaHandler:        mediaHandler,
+		config:              config,
+		handshakeSync:       &sync.Mutex{},
+	}
+}