fix: align Vertex content fetch flow with Gemini and handle base64 payloads

controller/video_proxy_gemini.go

@@ -145,6 +145,110 @@ func extractGeminiVideoURLFromGeneratedSamples(gvr map[string]any) string {
 	return ""
 }
 
+func getVertexVideoURL(channel *model.Channel, task *model.Task) (string, error) {
+	if channel == nil || task == nil {
+		return "", fmt.Errorf("invalid channel or task")
+	}
+	if url := strings.TrimSpace(task.GetResultURL()); url != "" {
+		return url, nil
+	}
+	if url := extractVertexVideoURLFromTaskData(task); url != "" {
+		return url, nil
+	}
+
+	baseURL := constant.ChannelBaseURLs[channel.Type]
+	if channel.GetBaseURL() != "" {
+		baseURL = channel.GetBaseURL()
+	}
+
+	adaptor := relay.GetTaskAdaptor(constant.TaskPlatform(strconv.Itoa(channel.Type)))
+	if adaptor == nil {
+		return "", fmt.Errorf("vertex task adaptor not found")
+	}
+
+	resp, err := adaptor.FetchTask(baseURL, channel.Key, map[string]any{
+		"task_id": task.GetUpstreamTaskID(),
+		"action":  task.Action,
+	}, channel.GetSetting().Proxy)
+	if err != nil {
+		return "", fmt.Errorf("fetch task failed: %w", err)
+	}
+	defer resp.Body.Close()
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return "", fmt.Errorf("read task response failed: %w", err)
+	}
+
+	taskInfo, parseErr := adaptor.ParseTaskResult(body)
+	if parseErr == nil && taskInfo != nil && strings.TrimSpace(taskInfo.Url) != "" {
+		return taskInfo.Url, nil
+	}
+	if url := extractVertexVideoURLFromPayload(body); url != "" {
+		return url, nil
+	}
+	if parseErr != nil {
+		return "", fmt.Errorf("parse task result failed: %w", parseErr)
+	}
+	return "", fmt.Errorf("vertex video url not found")
+}
+
+func extractVertexVideoURLFromTaskData(task *model.Task) string {
+	if task == nil || len(task.Data) == 0 {
+		return ""
+	}
+	return extractVertexVideoURLFromPayload(task.Data)
+}
+
+func extractVertexVideoURLFromPayload(body []byte) string {
+	var payload map[string]any
+	if err := common.Unmarshal(body, &payload); err != nil {
+		return ""
+	}
+	resp, ok := payload["response"].(map[string]any)
+	if !ok || resp == nil {
+		return ""
+	}
+
+	if videos, ok := resp["videos"].([]any); ok && len(videos) > 0 {
+		if video, ok := videos[0].(map[string]any); ok && video != nil {
+			if b64, _ := video["bytesBase64Encoded"].(string); strings.TrimSpace(b64) != "" {
+				mime, _ := video["mimeType"].(string)
+				enc, _ := video["encoding"].(string)
+				return buildVideoDataURL(mime, enc, b64)
+			}
+		}
+	}
+	if b64, _ := resp["bytesBase64Encoded"].(string); strings.TrimSpace(b64) != "" {
+		enc, _ := resp["encoding"].(string)
+		return buildVideoDataURL("", enc, b64)
+	}
+	if video, _ := resp["video"].(string); strings.TrimSpace(video) != "" {
+		if strings.HasPrefix(video, "data:") || strings.HasPrefix(video, "http://") || strings.HasPrefix(video, "https://") {
+			return video
+		}
+		enc, _ := resp["encoding"].(string)
+		return buildVideoDataURL("", enc, video)
+	}
+	return ""
+}
+
+func buildVideoDataURL(mimeType string, encoding string, base64Data string) string {
+	mime := strings.TrimSpace(mimeType)
+	if mime == "" {
+		enc := strings.TrimSpace(encoding)
+		if enc == "" {
+			enc = "mp4"
+		}
+		if strings.Contains(enc, "/") {
+			mime = enc
+		} else {
+			mime = "video/" + enc
+		}
+	}
+	return "data:" + mime + ";base64," + base64Data
+}
+
 func ensureAPIKey(uri, key string) string {
 	if key == "" || uri == "" {
 		return uri