From 5c8e985851e2857045755eba788b76450cedf01c Mon Sep 17 00:00:00 2001
From: Kai <kai@localhost>
Date: Tue, 17 Feb 2026 16:45:29 +0100
Subject: [PATCH] Matrix-Zeitzone konfigurierbar machen (Default Europe/Berlin)

---
 .env.example         |  1 +
 README.md            |  1 +
 cmd/server/matrix.go | 17 ++++++++++++++++-
 docker-compose.yml   |  1 +
 4 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/.env.example b/.env.example
index 29184a4..7465d7c 100644
--- a/.env.example
+++ b/.env.example
@@ -12,3 +12,4 @@ DB_DSN=farmcal:CHANGE_ME@tcp(127.0.0.1:3306)/farmcal?parseTime=true
 # MATRIX_ENABLE_CRYPTO=1
 # MATRIX_PICKLE_KEY=CHANGE_ME_LONG_RANDOM
 # MATRIX_CRYPTO_STORE_PATH=/tmp/farmcal-matrix-crypto.db
+# MATRIX_TIMEZONE=Europe/Berlin
diff --git a/README.md b/README.md
index 971bea0..10c8632 100644
--- a/README.md
+++ b/README.md
@@ -44,6 +44,7 @@ MATRIX_LIMIT=25
 MATRIX_ENABLE_CRYPTO=1
 MATRIX_PICKLE_KEY=LONG_RANDOM_SECRET
 MATRIX_CRYPTO_STORE_PATH=/tmp/farmcal-matrix-crypto.db
+MATRIX_TIMEZONE=Europe/Berlin
 ```
 
 - `MATRIX_ACCESS_TOKEN` sollte ein User-Token mit Leserechten fuer den Raum sein.
diff --git a/cmd/server/matrix.go b/cmd/server/matrix.go
index a0f7a13..ba76c21 100644
--- a/cmd/server/matrix.go
+++ b/cmd/server/matrix.go
@@ -21,6 +21,7 @@ type MatrixClient struct {
 	AccessToken   string
 	RoomID        string
 	Limit         int
+	TimeLocation  *time.Location
 	httpClient    *http.Client
 	crypto        *cryptohelper.CryptoHelper
 }
@@ -50,6 +51,12 @@ func newMatrixClientFromEnv() *MatrixClient {
 			Timeout: 8 * time.Second,
 		},
 	}
+	locName := strings.TrimSpace(readEnv("MATRIX_TIMEZONE", "Europe/Berlin"))
+	if loc, err := time.LoadLocation(locName); err == nil {
+		m.TimeLocation = loc
+	} else {
+		m.TimeLocation = time.Local
+	}
 
 	if readEnv("MATRIX_ENABLE_CRYPTO", "1") != "0" {
 		m.crypto = initMatrixCrypto(hs, token)
@@ -128,7 +135,7 @@ func (m *MatrixClient) FetchRecentMessages(ctx context.Context) ([]MatrixMessage
 }
 
 func (m *MatrixClient) mapEventToMessage(ctx context.Context, ev *event.Event) (MatrixMessage, bool) {
-	ts := time.UnixMilli(ev.Timestamp).Local().Format("02.01.2006 15:04")
+	ts := m.formatTimestamp(ev.Timestamp)
 	sender := shortMatrixSender(string(ev.Sender))
 
 	switch ev.Type {
@@ -152,6 +159,14 @@ func (m *MatrixClient) mapEventToMessage(ctx context.Context, ev *event.Event) (
 	}
 }
 
+func (m *MatrixClient) formatTimestamp(tsMillis int64) string {
+	loc := m.TimeLocation
+	if loc == nil {
+		loc = time.Local
+	}
+	return time.UnixMilli(tsMillis).In(loc).Format("02.01.2006 15:04")
+}
+
 func extractBody(ev *event.Event) (string, bool) {
 	if ev == nil {
 		return "", false
diff --git a/docker-compose.yml b/docker-compose.yml
index 724c835..2dbeda2 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -16,3 +16,4 @@ services:
       MATRIX_ENABLE_CRYPTO: "${MATRIX_ENABLE_CRYPTO:-1}"
       MATRIX_PICKLE_KEY: "${MATRIX_PICKLE_KEY:-}"
       MATRIX_CRYPTO_STORE_PATH: "${MATRIX_CRYPTO_STORE_PATH:-/tmp/farmcal-matrix-crypto.db}"
+      MATRIX_TIMEZONE: "${MATRIX_TIMEZONE:-Europe/Berlin}"