From d7e7d5b0f61e775d38efb58b14561cce42b984d1 Mon Sep 17 00:00:00 2001
From: valoq <valoq@mailbox.org>
Date: Sun, 12 Apr 2026 12:42:35 +0200
Subject: [PATCH] limit preview cache size

---
 app.go |  1 +
 nav.go | 19 +++++++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/app.go b/app.go
index 5d7510d1f..15692293b 100644
--- a/app.go
+++ b/app.go
@@ -432,6 +432,7 @@ func (app *app) loop() {
 			app.ui.draw(app.nav)
 		case r := <-app.nav.regChan:
 			app.nav.regCache[r.path] = r
+			app.nav.evictRegCache()
 
 			if curr := app.nav.currFile(); curr != nil {
 				if r.path == curr.path {
diff --git a/nav.go b/nav.go
index 7664ca466..57a1712f1 100644
--- a/nav.go
+++ b/nav.go
@@ -841,6 +841,7 @@ func (nav *nav) preload() {
 		}
 
 		nav.regCache[file.path] = &reg{loading: true, loadTime: time.Now(), path: file.path}
+		nav.evictRegCache()
 		select {
 		case nav.preloadChan <- file.path:
 		default:
@@ -955,6 +956,7 @@ func (nav *nav) loadReg(path string, volatile bool) *reg {
 	if !ok || (!gOpts.preload && r.loading) {
 		r = &reg{loading: true, loadTime: time.Now(), path: path}
 		nav.regCache[path] = r
+		nav.evictRegCache()
 		if gOpts.preload {
 			select {
 			case nav.preloadChan <- path:
@@ -2021,3 +2023,20 @@ func (nav *nav) calcDirSize() error {
 
 	return nil
 }
+
+const maxRegCacheSize = 512
+
+func (nav *nav) evictRegCache() {
+	if len(nav.regCache) <= maxRegCacheSize {
+		return
+	}
+	var oldestKey string
+	var oldestTime time.Time
+	for k, r := range nav.regCache {
+		if oldestKey == "" || r.loadTime.Before(oldestTime) {
+			oldestKey = k
+			oldestTime = r.loadTime
+		}
+	}
+	delete(nav.regCache, oldestKey)
+}