1 files changed, 198 insertions, 0 deletions
diff --git a/internal/cache/timeline/status_map.go b/internal/cache/timeline/status_map.go
new file mode 100644
index 000000000..e402883af
--- /dev/null
+++ b/internal/cache/timeline/status_map.go
@@ -0,0 +1,198 @@
+// 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 timeline
+
+import (
+	"maps"
+	"sync/atomic"
+)
+
+// StatusTimelines is a concurrency safe map of StatusTimeline{}
+// objects, optimizing *very heavily* for reads over writes.
+type StatusTimelines struct {
+	ptr atomic.Pointer[map[string]*StatusTimeline] // ronly except by CAS
+	cap int
+}
+
+// Init stores the given argument(s) such that any created StatusTimeline{}
+// objects by MustGet() will initialize them with the given arguments.
+func (t *StatusTimelines) Init(cap int) { t.cap = cap }
+
+// MustGet will attempt to fetch StatusTimeline{} stored under key, else creating one.
+func (t *StatusTimelines) MustGet(key string) *StatusTimeline {
+	var tt *StatusTimeline
+
+	for {
+		// Load current ptr.
+		cur := t.ptr.Load()
+
+		// Get timeline map to work on.
+		var m map[string]*StatusTimeline
+
+		if cur != nil {
+			// Look for existing
+			// timeline in cache.
+			tt = (*cur)[key]
+			if tt != nil {
+				return tt
+			}
+
+			// Get clone of current
+			// before modifications.
+			m = maps.Clone(*cur)
+		} else {
+			// Allocate new timeline map for below.
+			m = make(map[string]*StatusTimeline)
+		}
+
+		if tt == nil {
+			// Allocate new timeline.
+			tt = new(StatusTimeline)
+			tt.Init(t.cap)
+		}
+
+		// Store timeline
+		// in new map.
+		m[key] = tt
+
+		// Attempt to update the map ptr.
+		if !t.ptr.CompareAndSwap(cur, &m) {
+
+			// We failed the
+			// CAS, reloop.
+			continue
+		}
+
+		// Successfully inserted
+		// new timeline model.
+		return tt
+	}
+}
+
+// Delete will delete the stored StatusTimeline{} under key, if any.
+func (t *StatusTimelines) Delete(key string) {
+	for {
+		// Load current ptr.
+		cur := t.ptr.Load()
+
+		// Check for empty map / not in map.
+		if cur == nil || (*cur)[key] == nil {
+			return
+		}
+
+		// Get clone of current
+		// before modifications.
+		m := maps.Clone(*cur)
+
+		// Delete ID.
+		delete(m, key)
+
+		// Attempt to update the map ptr.
+		if !t.ptr.CompareAndSwap(cur, &m) {
+
+			// We failed the
+			// CAS, reloop.
+			continue
+		}
+
+		// Successfully
+		// deleted ID.
+		return
+	}
+}
+
+// RemoveByStatusIDs calls RemoveByStatusIDs() for each of the stored StatusTimeline{}s.
+func (t *StatusTimelines) RemoveByStatusIDs(statusIDs ...string) {
+	if p := t.ptr.Load(); p != nil {
+		for _, tt := range *p {
+			tt.RemoveByStatusIDs(statusIDs...)
+		}
+	}
+}
+
+// RemoveByAccountIDs calls RemoveByAccountIDs() for each of the stored StatusTimeline{}s.
+func (t *StatusTimelines) RemoveByAccountIDs(accountIDs ...string) {
+	if p := t.ptr.Load(); p != nil {
+		for _, tt := range *p {
+			tt.RemoveByAccountIDs(accountIDs...)
+		}
+	}
+}
+
+// UnprepareByStatusIDs calls UnprepareByStatusIDs() for each of the stored StatusTimeline{}s.
+func (t *StatusTimelines) UnprepareByStatusIDs(statusIDs ...string) {
+	if p := t.ptr.Load(); p != nil {
+		for _, tt := range *p {
+			tt.UnprepareByStatusIDs(statusIDs...)
+		}
+	}
+}
+
+// UnprepareByAccountIDs calls UnprepareByAccountIDs() for each of the stored StatusTimeline{}s.
+func (t *StatusTimelines) UnprepareByAccountIDs(accountIDs ...string) {
+	if p := t.ptr.Load(); p != nil {
+		for _, tt := range *p {
+			tt.UnprepareByAccountIDs(accountIDs...)
+		}
+	}
+}
+
+// Unprepare attempts to call UnprepareAll() for StatusTimeline{} under key.
+func (t *StatusTimelines) Unprepare(key string) {
+	if p := t.ptr.Load(); p != nil {
+		if tt := (*p)[key]; tt != nil {
+			tt.UnprepareAll()
+		}
+	}
+}
+
+// UnprepareAll calls UnprepareAll() for each of the stored StatusTimeline{}s.
+func (t *StatusTimelines) UnprepareAll() {
+	if p := t.ptr.Load(); p != nil {
+		for _, tt := range *p {
+			tt.UnprepareAll()
+		}
+	}
+}
+
+// Trim calls Trim() for each of the stored StatusTimeline{}s.
+func (t *StatusTimelines) Trim() {
+	if p := t.ptr.Load(); p != nil {
+		for _, tt := range *p {
+			tt.Trim()
+		}
+	}
+}
+
+// Clear attempts to call Clear() for StatusTimeline{} under key.
+func (t *StatusTimelines) Clear(key string) {
+	if p := t.ptr.Load(); p != nil {
+		if tt := (*p)[key]; tt != nil {
+			tt.Clear()
+		}
+	}
+}
+
+// ClearAll calls Clear() for each of the stored StatusTimeline{}s.
+func (t *StatusTimelines) ClearAll() {
+	if p := t.ptr.Load(); p != nil {
+		for _, tt := range *p {
+			tt.Clear()
+		}
+	}
+}