fix subscription dedup progress tracking

internal/service/telegram_api_proxy_test.go

@@ -0,0 +1,62 @@
+package service
+
+import (
+	"net/http"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestTelegramProxyCandidatesDefaultLocalFallbacks(t *testing.T) {
+	got := telegramProxyCandidates(map[string]string{})
+	joined := strings.Join(got, ",")
+	for _, want := range []string{"127.0.0.1:10808", "127.0.0.1:7890", "host.docker.internal:7890", "172.17.0.1:7890"} {
+		if !strings.Contains(joined, want) {
+			t.Fatalf("default proxy candidates %q missing %q", joined, want)
+		}
+	}
+}
+
+func TestTelegramHTTPClientsCustomAPIBaseSkipsDefaultProxyFallback(t *testing.T) {
+	clients := telegramHTTPClients(time.Second, map[string]string{
+		"api_base_url": "http://127.0.0.1:18080",
+	})
+	if len(clients) != 1 {
+		t.Fatalf("clients = %d, want direct client only", len(clients))
+	}
+	if got := telegramClientProxyString(t, clients[0]); got != "" {
+		t.Fatalf("custom api_base_url proxy = %q, want direct", got)
+	}
+}
+
+func TestTelegramHTTPClientsPreferConfiguredProxy(t *testing.T) {
+	clients := telegramHTTPClients(time.Second, map[string]string{
+		"proxy_url": "http://proxy.example:7890",
+	})
+	if len(clients) == 0 {
+		t.Fatal("expected telegram clients")
+	}
+	if got := telegramClientProxyString(t, clients[0]); got != "http://proxy.example:7890" {
+		t.Fatalf("first client proxy = %q, want configured proxy", got)
+	}
+}
+
+func telegramClientProxyString(t *testing.T, client *http.Client) string {
+	t.Helper()
+	transport, ok := client.Transport.(*http.Transport)
+	if !ok || transport.Proxy == nil {
+		return ""
+	}
+	req, err := http.NewRequest(http.MethodGet, defaultTelegramAPIBaseURL, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	proxyURL, err := transport.Proxy(req)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if proxyURL == nil {
+		return ""
+	}
+	return proxyURL.String()
+}