From f660f6c19aa91e50ef4d1753a454541ff39dec2c Mon Sep 17 00:00:00 2001
From: Carlosokumu <carlosokumu254@gmail.com>
Date: Thu, 9 Jan 2025 13:04:11 +0300
Subject: [PATCH 1/3] add key to hold selected langauge  code

---
 common/db.go | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/common/db.go b/common/db.go
index 5e2fc4c..2271716 100644
--- a/common/db.go
+++ b/common/db.go
@@ -57,6 +57,8 @@ const (
 	DATA_ACTIVE_ADDRESS
 	//Holds count of the number of incorrect PIN attempts
 	DATA_INCORRECT_PIN_ATTEMPTS
+	//ISO 639 code for the selected language.
+	DATA_SELECTED_LANGUAGE_CODE
 )
 
 const (

From 73eb7654085ef5edb326dd18e6e7b9a18d43b5a3 Mon Sep 17 00:00:00 2001
From: Carlosokumu <carlosokumu254@gmail.com>
Date: Thu, 9 Jan 2025 13:14:46 +0300
Subject: [PATCH 2/3] persist selected language code

---
 internal/handlers/ussd/menuhandler.go | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/internal/handlers/ussd/menuhandler.go b/internal/handlers/ussd/menuhandler.go
index 607b812..4b6a713 100644
--- a/internal/handlers/ussd/menuhandler.go
+++ b/internal/handlers/ussd/menuhandler.go
@@ -161,9 +161,12 @@ func (h *Handlers) SetLanguage(ctx context.Context, sym string, input []byte) (r
 		//Fallback to english instead?
 		code = "eng"
 	}
-	res.FlagSet = append(res.FlagSet, state.FLAG_LANG)
+	err := h.persistLanguageCode(ctx, code)
+	if err != nil {
+		return res, err
+	}
 	res.Content = code
-
+	res.FlagSet = append(res.FlagSet, state.FLAG_LANG)
 	languageSetFlag, err := h.flagManager.GetFlag("flag_language_set")
 	if err != nil {
 		logg.ErrorCtxf(ctx, "Error setting the languageSetFlag", "error", err)
@@ -2173,3 +2176,18 @@ func (h *Handlers) resetIncorrectPINAttempts(ctx context.Context, sessionId stri
 	}
 	return nil
 }
+
+// persistLanguageCode persists the selected ISO 639 language code
+func (h *Handlers) persistLanguageCode(ctx context.Context, code string) error {
+	store := h.userdataStore
+	sessionId, ok := ctx.Value("SessionId").(string)
+	if !ok {
+		return fmt.Errorf("missing session")
+	}
+	err := store.WriteEntry(ctx, sessionId, common.DATA_SELECTED_LANGUAGE_CODE, []byte(code))
+	if err != nil {
+		logg.ErrorCtxf(ctx, "failed to persist language code", "key", common.DATA_SELECTED_LANGUAGE_CODE, "value", code, "error", err)
+		return err
+	}
+	return nil
+}

From 3747f87a7ce18c8ccf53f21ef723ffce1e7f73fc Mon Sep 17 00:00:00 2001
From: Carlosokumu <carlosokumu254@gmail.com>
Date: Thu, 9 Jan 2025 15:11:29 +0300
Subject: [PATCH 3/3] test language code saving

---
 internal/handlers/ussd/menuhandler_test.go | 50 ++++++++++++++++++++--
 1 file changed, 47 insertions(+), 3 deletions(-)

diff --git a/internal/handlers/ussd/menuhandler_test.go b/internal/handlers/ussd/menuhandler_test.go
index af1380d..29f6948 100644
--- a/internal/handlers/ussd/menuhandler_test.go
+++ b/internal/handlers/ussd/menuhandler_test.go
@@ -775,6 +775,11 @@ func TestSetLanguage(t *testing.T) {
 		log.Fatal(err)
 	}
 
+	sessionId := "session123"
+	ctx, store := InitializeTestStore(t)
+
+	ctx = context.WithValue(ctx, "SessionId", sessionId)
+
 	// Define test cases
 	tests := []struct {
 		name           string
@@ -807,12 +812,13 @@ func TestSetLanguage(t *testing.T) {
 
 			// Create the Handlers instance with the mock flag manager
 			h := &Handlers{
-				flagManager: fm.parser,
-				st:          mockState,
+				flagManager:   fm.parser,
+				userdataStore: store,
+				st:            mockState,
 			}
 
 			// Call the method
-			res, err := h.SetLanguage(context.Background(), "set_language", nil)
+			res, err := h.SetLanguage(ctx, "set_language", nil)
 			if err != nil {
 				t.Error(err)
 			}
@@ -2285,3 +2291,41 @@ func TestResetIncorrectPINAttempts(t *testing.T) {
 	assert.Equal(t, "0", string(incorrectAttempts))
 
 }
+
+func TestPersistLanguageCode(t *testing.T) {
+	ctx, store := InitializeTestStore(t)
+
+	sessionId := "session123"
+	ctx = context.WithValue(ctx, "SessionId", sessionId)
+
+	h := &Handlers{
+		userdataStore: store,
+	}
+	tests := []struct {
+		name                 string
+		code                 string
+		expectedLanguageCode string
+	}{
+		{
+			name:                 "Set Default Language (English)",
+			code:                 "eng",
+			expectedLanguageCode: "eng",
+		},
+		{
+			name:                 "Set Swahili Language",
+			code:                 "swa",
+			expectedLanguageCode: "swa",
+		},
+	}
+
+	for _, test := range tests {
+		err := h.persistLanguageCode(ctx, test.code)
+		if err != nil {
+			t.Logf(err.Error())
+		}
+		code, err := store.ReadEntry(ctx, sessionId, common.DATA_SELECTED_LANGUAGE_CODE)
+
+		assert.Equal(t, test.expectedLanguageCode, string(code))
+	}
+
+}