Improve translation fallback and scale UI

backend/services/gemini.go

@@ -8,6 +8,7 @@ import (
 	"io"
 	"mime"
 	"net/http"
+	neturl "net/url"
 	"strings"
 	"time"
 )
@@ -201,15 +202,17 @@ func (g *GeminiService) TranslateQuery(query string) string {
 	}
 
 	rawText, err := g.generateText(body)
-	if err != nil {
-		return strings.TrimSpace(query)
+	if err == nil {
+		translated := sanitizePlainEnglishLine(rawText)
+		if translated != "" && !strings.EqualFold(translated, strings.TrimSpace(query)) {
+			return translated
+		}
 	}
 
-	translated := sanitizePlainEnglishLine(rawText)
-	if translated == "" {
-		return strings.TrimSpace(query)
+	if translated, err := g.translateViaGoogle(query); err == nil && translated != "" {
+		return translated
 	}
-	return translated
+	return strings.TrimSpace(query)
 }
 
 func (g *GeminiService) generateText(body map[string]any) (string, error) {
@@ -464,10 +467,6 @@ func fallbackQueryExpansion(originalQuery, englishQuery string) []string {
 		base + " 4k footage",
 		base + " cinematic b-roll",
 	}
-	if strings.TrimSpace(originalQuery) != "" && !strings.EqualFold(strings.TrimSpace(originalQuery), strings.TrimSpace(englishQuery)) {
-		candidates = append(candidates, strings.TrimSpace(originalQuery))
-	}
-
 	seen := map[string]bool{}
 	queries := make([]string, 0, len(candidates))
 	for _, item := range candidates {
@@ -519,3 +518,44 @@ func looksMostlyASCII(text string) bool {
 	}
 	return ascii >= len(runes)*8/10
 }
+
+func (g *GeminiService) translateViaGoogle(query string) (string, error) {
+	endpoint := "https://translate.googleapis.com/translate_a/single?client=gtx&sl=auto&tl=en&dt=t&q=" + neturl.QueryEscape(query)
+	resp, err := g.Client.Get(endpoint)
+	if err != nil {
+		return "", err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode >= 300 {
+		return "", fmt.Errorf("google translate fallback returned status %d", resp.StatusCode)
+	}
+
+	var payload []any
+	if err := json.NewDecoder(resp.Body).Decode(&payload); err != nil {
+		return "", err
+	}
+	if len(payload) == 0 {
+		return "", fmt.Errorf("google translate fallback returned no payload")
+	}
+	top, ok := payload[0].([]any)
+	if !ok {
+		return "", fmt.Errorf("google translate fallback returned unexpected payload")
+	}
+
+	var builder strings.Builder
+	for _, part := range top {
+		segment, ok := part.([]any)
+		if !ok || len(segment) == 0 {
+			continue
+		}
+		if text, ok := segment[0].(string); ok {
+			builder.WriteString(text)
+		}
+	}
+	translated := strings.TrimSpace(builder.String())
+	if translated == "" {
+		return "", fmt.Errorf("google translate fallback returned empty translation")
+	}
+	return translated, nil
+}