feat: mail service

authsession/internal/service/sendemailcode/service_test.go

@@ -72,6 +72,9 @@ func TestExecuteSendsChallengeForExistingAndCreatableUsers(t *testing.T) {
 			if len(mailSender.RecordedInputs()) != 1 {
 				require.Failf(t, "test failed", "RecordedInputs() length = %d, want 1", len(mailSender.RecordedInputs()))
 			}
+			if mailSender.RecordedInputs()[0].Locale != "en" {
+				require.Failf(t, "test failed", "mail locale = %q, want %q", mailSender.RecordedInputs()[0].Locale, "en")
+			}
 
 			record, err := challengeStore.Get(context.Background(), common.ChallengeID("challenge-1"))
 			if err != nil {
@@ -83,6 +86,9 @@ func TestExecuteSendsChallengeForExistingAndCreatableUsers(t *testing.T) {
 			if record.Attempts.Send != 1 {
 				require.Failf(t, "test failed", "Attempts.Send = %d, want 1", record.Attempts.Send)
 			}
+			if record.PreferredLanguage != "en" {
+				require.Failf(t, "test failed", "PreferredLanguage = %q, want %q", record.PreferredLanguage, "en")
+			}
 			if string(record.CodeHash) == "654321" {
 				require.FailNow(t, "CodeHash stored cleartext code")
 			}
@@ -131,6 +137,9 @@ func TestExecuteSuppressesDeliveryForBlockedEmail(t *testing.T) {
 	if record.Status != challenge.StatusDeliverySuppressed || record.DeliveryState != challenge.DeliverySuppressed {
 		require.Failf(t, "test failed", "challenge state = %q/%q", record.Status, record.DeliveryState)
 	}
+	if record.PreferredLanguage != "en" {
+		require.Failf(t, "test failed", "PreferredLanguage = %q, want %q", record.PreferredLanguage, "en")
+	}
 }
 
 func TestExecuteHandlesMailSenderSuppressedOutcome(t *testing.T) {
@@ -166,6 +175,9 @@ func TestExecuteHandlesMailSenderSuppressedOutcome(t *testing.T) {
 	if record.Status != challenge.StatusDeliverySuppressed || record.DeliveryState != challenge.DeliverySuppressed {
 		require.Failf(t, "test failed", "challenge state = %q/%q", record.Status, record.DeliveryState)
 	}
+	if record.PreferredLanguage != "en" {
+		require.Failf(t, "test failed", "PreferredLanguage = %q, want %q", record.PreferredLanguage, "en")
+	}
 }
 
 func TestExecuteMarksChallengeFailedWhenMailSenderFails(t *testing.T) {
@@ -199,6 +211,9 @@ func TestExecuteMarksChallengeFailedWhenMailSenderFails(t *testing.T) {
 	if record.Status != challenge.StatusFailed || record.DeliveryState != challenge.DeliveryFailed {
 		require.Failf(t, "test failed", "challenge state = %q/%q", record.Status, record.DeliveryState)
 	}
+	if record.PreferredLanguage != "en" {
+		require.Failf(t, "test failed", "PreferredLanguage = %q, want %q", record.PreferredLanguage, "en")
+	}
 }
 
 func TestExecuteReturnsInvalidRequestForBadEmail(t *testing.T) {
@@ -308,3 +323,69 @@ func TestExecuteSetsChallengeExpirationFromInitialTTL(t *testing.T) {
 		require.Failf(t, "test failed", "ExpiresAt = %s, want %s", record.ExpiresAt, wantExpiresAt)
 	}
 }
+
+func TestExecuteResolvesPreferredLanguageFromAcceptLanguage(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name              string
+		acceptLanguage    string
+		wantPreferredLang string
+	}{
+		{
+			name:              "canonical valid tag wins",
+			acceptLanguage:    "fr-FR, en;q=0.8",
+			wantPreferredLang: "fr-FR",
+		},
+		{
+			name:              "wildcard falls back to english",
+			acceptLanguage:    "*",
+			wantPreferredLang: "en",
+		},
+		{
+			name:              "malformed header falls back to english",
+			acceptLanguage:    "fr-FR, @@",
+			wantPreferredLang: "en",
+		},
+		{
+			name:              "missing header falls back to english",
+			acceptLanguage:    "",
+			wantPreferredLang: "en",
+		},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+
+			challengeStore := &testkit.InMemoryChallengeStore{}
+			mailSender := &testkit.RecordingMailSender{}
+			service, err := New(
+				challengeStore,
+				&testkit.InMemoryUserDirectory{},
+				&testkit.SequenceIDGenerator{ChallengeIDs: []common.ChallengeID{"challenge-1"}},
+				testkit.FixedCodeGenerator{Code: "654321"},
+				testkit.DeterministicCodeHasher{},
+				mailSender,
+				testkit.FixedClock{Time: time.Unix(10, 0).UTC()},
+			)
+			require.NoError(t, err)
+
+			_, err = service.Execute(context.Background(), Input{
+				Email:          "pilot@example.com",
+				AcceptLanguage: tt.acceptLanguage,
+			})
+			require.NoError(t, err)
+
+			record, err := challengeStore.Get(context.Background(), common.ChallengeID("challenge-1"))
+			require.NoError(t, err)
+			require.Equal(t, tt.wantPreferredLang, record.PreferredLanguage)
+
+			attempts := mailSender.RecordedInputs()
+			require.Len(t, attempts, 1)
+			require.Equal(t, tt.wantPreferredLang, attempts[0].Locale)
+		})
+	}
+}