/*
   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 federatingdb

import (
	"context"
	"encoding/json"
	"errors"
	"fmt"

	"github.com/go-fed/activity/streams"
	"github.com/go-fed/activity/streams/vocab"
	"github.com/sirupsen/logrus"
	"github.com/superseriousbusiness/gotosocial/internal/ap"
	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
	"github.com/superseriousbusiness/gotosocial/internal/messages"
	"github.com/superseriousbusiness/gotosocial/internal/util"
)

// Update sets an existing entry to the database based on the value's
// id.
//
// Note that Activity values received from federated peers may also be
// updated in the database this way if the Federating Protocol is
// enabled. The client may freely decide to store only the id instead of
// the entire value.
//
// The library makes this call only after acquiring a lock first.
func (f *federatingDB) Update(ctx context.Context, asType vocab.Type) error {
	l := f.log.WithFields(
		logrus.Fields{
			"func":   "Update",
			"asType": asType.GetTypeName(),
		},
	)
	m, err := streams.Serialize(asType)
	if err != nil {
		return err
	}
	b, err := json.Marshal(m)
	if err != nil {
		return err
	}

	l.Debugf("received UPDATE asType %s", string(b))

	targetAcctI := ctx.Value(util.APAccount)
	if targetAcctI == nil {
		// If the target account wasn't set on the context, that means this request didn't pass through the
		// API, but came from inside GtS as the result of another activity on this instance. That being so,
		// we can safely just ignore this activity, since we know we've already processed it elsewhere.
		return nil
	}
	targetAcct, ok := targetAcctI.(*gtsmodel.Account)
	if !ok {
		l.Error("UPDATE: target account was set on context but couldn't be parsed")
	}

	requestingAcctI := ctx.Value(util.APRequestingAccount)
	if targetAcctI == nil {
		l.Error("UPDATE: requesting account wasn't set on context")
	}
	requestingAcct, ok := requestingAcctI.(*gtsmodel.Account)
	if !ok {
		l.Error("UPDATE: requesting account was set on context but couldn't be parsed")
	}

	fromFederatorChanI := ctx.Value(util.APFromFederatorChanKey)
	if fromFederatorChanI == nil {
		l.Error("UPDATE: from federator channel wasn't set on context")
	}
	fromFederatorChan, ok := fromFederatorChanI.(chan messages.FromFederator)
	if !ok {
		l.Error("UPDATE: from federator channel was set on context but couldn't be parsed")
	}

	typeName := asType.GetTypeName()
	if typeName == ap.ActorApplication ||
		typeName == ap.ActorGroup ||
		typeName == ap.ActorOrganization ||
		typeName == ap.ActorPerson ||
		typeName == ap.ActorService {
		// it's an UPDATE to some kind of account
		var accountable ap.Accountable

		switch asType.GetTypeName() {
		case ap.ActorApplication:
			l.Debug("got update for APPLICATION")
			i, ok := asType.(vocab.ActivityStreamsApplication)
			if !ok {
				return errors.New("UPDATE: could not convert type to application")
			}
			accountable = i
		case ap.ActorGroup:
			l.Debug("got update for GROUP")
			i, ok := asType.(vocab.ActivityStreamsGroup)
			if !ok {
				return errors.New("UPDATE: could not convert type to group")
			}
			accountable = i
		case ap.ActorOrganization:
			l.Debug("got update for ORGANIZATION")
			i, ok := asType.(vocab.ActivityStreamsOrganization)
			if !ok {
				return errors.New("UPDATE: could not convert type to organization")
			}
			accountable = i
		case ap.ActorPerson:
			l.Debug("got update for PERSON")
			i, ok := asType.(vocab.ActivityStreamsPerson)
			if !ok {
				return errors.New("UPDATE: could not convert type to person")
			}
			accountable = i
		case ap.ActorService:
			l.Debug("got update for SERVICE")
			i, ok := asType.(vocab.ActivityStreamsService)
			if !ok {
				return errors.New("UPDATE: could not convert type to service")
			}
			accountable = i
		}

		updatedAcct, err := f.typeConverter.ASRepresentationToAccount(ctx, accountable, true)
		if err != nil {
			return fmt.Errorf("UPDATE: error converting to account: %s", err)
		}

		if updatedAcct.Domain == f.config.Host {
			// no need to update local accounts
			// in fact, if we do this will break the shit out of things so do NOT
			return nil
		}

		if requestingAcct.URI != updatedAcct.URI {
			return fmt.Errorf("UPDATE: update for account %s was requested by account %s, this is not valid", updatedAcct.URI, requestingAcct.URI)
		}

		updatedAcct.ID = requestingAcct.ID // set this here so the db will update properly instead of trying to PUT this and getting constraint issues
		updatedAcct, err = f.db.UpdateAccount(ctx, updatedAcct)
		if err != nil {
			return fmt.Errorf("UPDATE: database error inserting updated account: %s", err)
		}

		fromFederatorChan <- messages.FromFederator{
			APObjectType:     ap.ObjectProfile,
			APActivityType:   ap.ActivityUpdate,
			GTSModel:         updatedAcct,
			ReceivingAccount: targetAcct,
		}

	}

	return nil
}