Harden preview enrichment and recommendation metadata

backend/services/gemini_test.go

@@ -3,6 +3,7 @@ package services
 import (
 	"net/http"
 	"net/http/httptest"
+	"strings"
 	"testing"
 	"time"
 )
@@ -114,3 +115,27 @@ func TestGeminiExpansionCacheRoundTrip(t *testing.T) {
 		t.Fatalf("unexpected expansion cache value: %#v", value)
 	}
 }
+
+func TestDecorateRecommendationMediaUsesEmbedForGoogleVideo(t *testing.T) {
+	item := DecorateRecommendationMedia(AIRecommendation{
+		Source: "Google Video",
+		Link:   "https://www.youtube.com/watch?v=dQw4w9WgXcQ",
+	})
+	if item.MediaMode != "embed" {
+		t.Fatalf("expected embed media mode, got %q", item.MediaMode)
+	}
+	if item.EmbedURL == "" || !strings.Contains(item.EmbedURL, "youtube-nocookie.com/embed/") {
+		t.Fatalf("unexpected embed url: %q", item.EmbedURL)
+	}
+}
+
+func TestRankSearchResultsPrefersUsableVisuals(t *testing.T) {
+	results := []SearchResult{
+		{Title: "cyberpunk city", Link: "https://example.com/a", ThumbnailURL: "https://example.com/favicon.ico"},
+		{Title: "cyberpunk city", Link: "https://example.com/b", ThumbnailURL: "https://example.com/frame.jpg"},
+	}
+	ranked := RankSearchResults("cyberpunk city", results)
+	if ranked[0].Link != "https://example.com/b" {
+		t.Fatalf("expected usable thumbnail result first, got %#v", ranked)
+	}
+}