// GoToSocial
// Copyright (C) GoToSocial Authors admin@gotosocial.org
// SPDX-License-Identifier: AGPL-3.0-or-later
//
// 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 subscriptions

import (
	"context"
	"encoding/csv"
	"errors"
	"time"

	"github.com/superseriousbusiness/gotosocial/internal/db"
	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
	"github.com/superseriousbusiness/gotosocial/internal/log"
	"github.com/superseriousbusiness/gotosocial/internal/state"
	"github.com/superseriousbusiness/gotosocial/internal/transport"
	"github.com/superseriousbusiness/gotosocial/internal/util"
)

type Subscriptions struct {
	state               *state.State
	transportController transport.Controller
}

func (s *Subscriptions) UpdateDomainPermissions(
	ctx context.Context,
	permType gtsmodel.DomainPermissionType,
) {
	l := log.
		WithContext(ctx).
		WithField("permType", permType.String())
	l.Info("start")

	// Get permission subscriptions in priority order (highest -> lowest).
	permSubs, err := s.state.DB.GetDomainPermissionSubscriptionsByPriority(ctx, permType)
	if err != nil && !errors.Is(err, db.ErrNoEntries) {
		// Real db error.
		l.Error(err)
		return
	}

	if len(permSubs) == 0 {
		// No subscriptions of this
		// type, so nothing to do.
		return
	}

	// Get a transport using the instance account,
	// we can reuse this for each HTTP call.
	tsport, err := s.transportController.NewTransportForUsername(ctx, "")
	if err != nil {
		l.Error(err)
		return
	}

	for i, permSub := range permSubs {
		// Set FetchedAt as we're
		// going to attempt this now.
		permSub.FetchedAt = time.Now()
		columns := []string{"fetched_at"}

		// Call the URI but don't force.
		resp, err := tsport.DereferenceDomainPermissions(
			ctx, permSub, false,
		)
		if err != nil {
			// Bollocks, couldn't get this one.
			// Just save the error in the db
			// for later perusal by admin.
			permSub.Error = err.Error()
			columns = append(columns, "error")
			if err := s.state.DB.UpdateDomainPermissionSubscription(
				ctx, permSub, columns...,
			); err != nil {
				// Real db error.
				l.Error(err)
				return
			}

			// Skip to the
			// next permSub.
			continue
		}

		// If the permissions at URI weren't modified
		// since last time, just update some metadata
		// and call this a successful fetch.
		if resp.Unmodified {
			permSub.SuccessfullyFetchedAt = time.Now()
			columns = append(columns, "successfully_fetched_at")

			if permSub.ETag == "" && resp.ETag != "" {
				// We didn't have an ETag before but
				// we have one now: probably the remote
				// added ETag support in the meantime.
				permSub.ETag = resp.ETag
				columns = append(columns, "etag")
			}

			if err := s.state.DB.UpdateDomainPermissionSubscription(
				ctx, permSub, columns...,
			); err != nil {
				// Real db error.
				l.Error(err)
				return
			}

			// Skip to the
			// next permSub.
			continue
		}

		// At this point we know we got a 200 OK from
		// the URI, so we've got a live body. Make sure
		// we close it when done, wrapping the close func
		// with DoOnce for more granular control.
		close := util.DoOnce(func() { resp.Body.Close() })
		defer close()

		// Try to parse the body as a
		// list of domain permissions.
		switch permSub.ContentType {

		// text/csv
		case gtsmodel.DomainPermSubContentTypeCSV:
			records, err := csv.NewReader(resp.Body).ReadAll()
			if err != nil {
				
			}

		// application/json
		case gtsmodel.DomainPermSubContentTypeJSON:

		// text/plain
		case gtsmodel.DomainPermSubContentTypePlain:
		}

		// Slice of permission subscriptions that have
		// a higher priority than this one. We should
		// not override perms if they already exist
		// under a higher-priority subscription.
		higherPrios := permSubs[:i]
	}
}