favourites GET implementation (#95)

3 files changed, 201 insertions, 89 deletions

diff --git a/internal/db/db.go b/internal/db/db.go
index 1d7ed8b58..0a3979df6 100644
--- a/internal/db/db.go
+++ b/internal/db/db.go
@@ -241,13 +241,26 @@ type DB interface {
 	// This slice will be unfiltered, not taking account of blocks and whatnot, so filter it before serving it back to a user.
 	WhoBoostedStatus(status *gtsmodel.Status) ([]*gtsmodel.Account, error)
 
-	// GetStatusesWhereFollowing returns a slice of statuses from accounts that are followed by the given account id.
-	GetStatusesWhereFollowing(accountID string, maxID string, sinceID string, minID string, limit int, local bool) ([]*gtsmodel.Status, error)
+	// GetHomeTimelineForAccount returns a slice of statuses from accounts that are followed by the given account id.
+	//
+	// Statuses should be returned in descending order of when they were created (newest first).
+	GetHomeTimelineForAccount(accountID string, maxID string, sinceID string, minID string, limit int, local bool) ([]*gtsmodel.Status, error)
 
-	// GetPublicTimelineForAccount fetches the account's PUBLIC timline -- ie., posts and replies that are public.
+	// GetPublicTimelineForAccount fetches the account's PUBLIC timeline -- ie., posts and replies that are public.
 	// It will use the given filters and try to return as many statuses as possible up to the limit.
+	//
+	// Statuses should be returned in descending order of when they were created (newest first).
 	GetPublicTimelineForAccount(accountID string, maxID string, sinceID string, minID string, limit int, local bool) ([]*gtsmodel.Status, error)
 
+	// GetFavedTimelineForAccount fetches the account's FAVED timeline -- ie., posts and replies that the requesting account has faved.
+	// It will use the given filters and try to return as many statuses as possible up to the limit.
+	//
+	// Note that unlike the other GetTimeline functions, the returned statuses will be arranged by their FAVE id, not the STATUS id.
+	// In other words, they'll be returned in descending order of when they were faved by the requesting user, not when they were created.
+	//
+	// Also note the extra return values, which correspond to the nextMaxID and prevMinID for building Link headers.
+	GetFavedTimelineForAccount(accountID string, maxID string, minID string, limit int) ([]*gtsmodel.Status, string, string, error)
+
 	// GetNotificationsForAccount returns a list of notifications that pertain to the given accountID.
 	GetNotificationsForAccount(accountID string, limit int, maxID string, sinceID string) ([]*gtsmodel.Notification, error)
 
diff --git a/internal/db/pg/pg.go b/internal/db/pg/pg.go
index 614968e22..ad75cef15 100644
--- a/internal/db/pg/pg.go
+++ b/internal/db/pg/pg.go
@@ -814,92 +814,6 @@ func (ps *postgresService) WhoBoostedStatus(status *gtsmodel.Status) ([]*gtsmode
 	return accounts, nil
 }
 
-func (ps *postgresService) GetStatusesWhereFollowing(accountID string, maxID string, sinceID string, minID string, limit int, local bool) ([]*gtsmodel.Status, error) {
-	statuses := []*gtsmodel.Status{}
-
-	q := ps.conn.Model(&statuses)
-
-	q = q.ColumnExpr("status.*").
-		Join("JOIN follows AS f ON f.target_account_id = status.account_id").
-		Where("f.account_id = ?", accountID).
-		Order("status.id DESC")
-
-	if maxID != "" {
-		q = q.Where("status.id < ?", maxID)
-	}
-
-	if sinceID != "" {
-		q = q.Where("status.id > ?", sinceID)
-	}
-
-	if minID != "" {
-		q = q.Where("status.id > ?", minID)
-	}
-
-	if local {
-		q = q.Where("status.local = ?", local)
-	}
-
-	if limit > 0 {
-		q = q.Limit(limit)
-	}
-
-	err := q.Select()
-	if err != nil {
-		if err == pg.ErrNoRows {
-			return nil, db.ErrNoEntries{}
-		}
-		return nil, err
-	}
-
-	if len(statuses) == 0 {
-		return nil, db.ErrNoEntries{}
-	}
-
-	return statuses, nil
-}
-
-func (ps *postgresService) GetPublicTimelineForAccount(accountID string, maxID string, sinceID string, minID string, limit int, local bool) ([]*gtsmodel.Status, error) {
-	statuses := []*gtsmodel.Status{}
-
-	q := ps.conn.Model(&statuses).
-		Where("visibility = ?", gtsmodel.VisibilityPublic).
-		Where("? IS NULL", pg.Ident("in_reply_to_id")).
-		Where("? IS NULL", pg.Ident("in_reply_to_uri")).
-		Where("? IS NULL", pg.Ident("boost_of_id")).
-		Order("status.id DESC")
-
-	if maxID != "" {
-		q = q.Where("status.id < ?", maxID)
-	}
-
-	if sinceID != "" {
-		q = q.Where("status.id > ?", sinceID)
-	}
-
-	if minID != "" {
-		q = q.Where("status.id > ?", minID)
-	}
-
-	if local {
-		q = q.Where("status.local = ?", local)
-	}
-
-	if limit > 0 {
-		q = q.Limit(limit)
-	}
-
-	err := q.Select()
-	if err != nil {
-		if err == pg.ErrNoRows {
-			return nil, db.ErrNoEntries{}
-		}
-		return nil, err
-	}
-
-	return statuses, nil
-}
-
 func (ps *postgresService) GetNotificationsForAccount(accountID string, limit int, maxID string, sinceID string) ([]*gtsmodel.Notification, error) {
 	notifications := []*gtsmodel.Notification{}
 
diff --git a/internal/db/pg/timeline.go b/internal/db/pg/timeline.go
new file mode 100644
index 000000000..95acd4f38
--- /dev/null
+++ b/internal/db/pg/timeline.go
@@ -0,0 +1,185 @@
+/*
+   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 pg
+
+import (
+	"sort"
+
+	"github.com/go-pg/pg/v10"
+	"github.com/superseriousbusiness/gotosocial/internal/db"
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+)
+
+func (ps *postgresService) GetHomeTimelineForAccount(accountID string, maxID string, sinceID string, minID string, limit int, local bool) ([]*gtsmodel.Status, error) {
+	statuses := []*gtsmodel.Status{}
+
+	q := ps.conn.Model(&statuses)
+
+	q = q.ColumnExpr("status.*").
+		Join("LEFT JOIN follows AS f ON f.target_account_id = status.account_id").
+		Where("f.account_id = ?", accountID).
+		Order("status.id DESC")
+
+	if maxID != "" {
+		q = q.Where("status.id < ?", maxID)
+	}
+
+	if sinceID != "" {
+		q = q.Where("status.id > ?", sinceID)
+	}
+
+	if minID != "" {
+		q = q.Where("status.id > ?", minID)
+	}
+
+	if local {
+		q = q.Where("status.local = ?", local)
+	}
+
+	if limit > 0 {
+		q = q.Limit(limit)
+	}
+
+	err := q.Select()
+	if err != nil {
+		if err == pg.ErrNoRows {
+			return nil, db.ErrNoEntries{}
+		}
+		return nil, err
+	}
+
+	if len(statuses) == 0 {
+		return nil, db.ErrNoEntries{}
+	}
+
+	return statuses, nil
+}
+
+func (ps *postgresService) GetPublicTimelineForAccount(accountID string, maxID string, sinceID string, minID string, limit int, local bool) ([]*gtsmodel.Status, error) {
+	statuses := []*gtsmodel.Status{}
+
+	q := ps.conn.Model(&statuses).
+		Where("visibility = ?", gtsmodel.VisibilityPublic).
+		Where("? IS NULL", pg.Ident("in_reply_to_id")).
+		Where("? IS NULL", pg.Ident("in_reply_to_uri")).
+		Where("? IS NULL", pg.Ident("boost_of_id")).
+		Order("status.id DESC")
+
+	if maxID != "" {
+		q = q.Where("status.id < ?", maxID)
+	}
+
+	if sinceID != "" {
+		q = q.Where("status.id > ?", sinceID)
+	}
+
+	if minID != "" {
+		q = q.Where("status.id > ?", minID)
+	}
+
+	if local {
+		q = q.Where("status.local = ?", local)
+	}
+
+	if limit > 0 {
+		q = q.Limit(limit)
+	}
+
+	err := q.Select()
+	if err != nil {
+		if err == pg.ErrNoRows {
+			return nil, db.ErrNoEntries{}
+		}
+		return nil, err
+	}
+
+	if len(statuses) == 0 {
+		return nil, db.ErrNoEntries{}
+	}
+
+	return statuses, nil
+}
+
+// TODO optimize this query and the logic here, because it's slow as balls -- it takes like a literal second to return with a limit of 20!
+// It might be worth serving it through a timeline instead of raw DB queries, like we do for Home feeds.
+func (ps *postgresService) GetFavedTimelineForAccount(accountID string, maxID string, minID string, limit int) ([]*gtsmodel.Status, string, string, error) {
+
+	faves := []*gtsmodel.StatusFave{}
+
+	fq := ps.conn.Model(&faves).
+		Where("account_id = ?", accountID).
+		Order("id DESC")
+
+	if maxID != "" {
+		fq = fq.Where("id < ?", maxID)
+	}
+
+	if minID != "" {
+		fq = fq.Where("id > ?", minID)
+	}
+
+	if limit > 0 {
+		fq = fq.Limit(limit)
+	}
+
+	err := fq.Select()
+	if err != nil {
+		if err == pg.ErrNoRows {
+			return nil, "", "", db.ErrNoEntries{}
+		}
+		return nil, "", "", err
+	}
+
+	if len(faves) == 0 {
+		return nil, "", "", db.ErrNoEntries{}
+	}
+
+	// map[statusID]faveID -- we need this to sort statuses by fave ID rather than their own ID
+	statusesFavesMap := map[string]string{}
+
+	in := []string{}
+	for _, f := range faves {
+		statusesFavesMap[f.StatusID] = f.ID
+		in = append(in, f.StatusID)
+	}
+
+	statuses := []*gtsmodel.Status{}
+	err = ps.conn.Model(&statuses).Where("id IN (?)", pg.In(in)).Select()
+	if err != nil {
+		if err == pg.ErrNoRows {
+			return nil, "", "", db.ErrNoEntries{}
+		}
+		return nil, "", "", err
+	}
+
+	if len(statuses) == 0 {
+		return nil, "", "", db.ErrNoEntries{}
+	}
+
+	// arrange statuses by fave ID
+	sort.Slice(statuses, func(i int, j int) bool {
+		statusI := statuses[i]
+		statusJ := statuses[j]
+		return statusesFavesMap[statusI.ID] < statusesFavesMap[statusJ.ID]
+	})
+
+	nextMaxID := faves[len(faves)-1].ID
+	prevMinID := faves[0].ID
+	return statuses, nextMaxID, prevMinID, nil
+}