fix(canvas): block invalid video duration confirmation

src/pages/ImageCanvas/index.tsx

@@ -268,6 +268,20 @@ type EditableGenerationParameters = Partial<Pick<
 const MIN_VIDEO_DURATION_SECONDS = 2;
 const MAX_VIDEO_DURATION_SECONDS = 6;
 
+function hasSelectableVideoDuration(
+  quote: DesignGenerationQuote,
+  parameters: DesignGenerationParameters,
+): boolean {
+  if (quote.medium !== 'video') return true;
+  const durationSeconds = parameters.durationSeconds;
+  return durationSeconds !== null
+    && durationSeconds >= MIN_VIDEO_DURATION_SECONDS
+    && durationSeconds <= MAX_VIDEO_DURATION_SECONDS
+    && quote.generationOptions.durations.some((option) => (
+      !option.disabled && option.value === durationSeconds
+    ));
+}
+
 function quoteDraftFromQuote(quote: DesignGenerationQuote): GenerationQuoteDraft {
   return {
     quoteId: quote.quoteId,
@@ -740,6 +754,10 @@ function QuoteCard({
   const selectedDuration = availableDurations.some(
     (option) => option.value === draft.generationParameters.durationSeconds,
   ) ? String(draft.generationParameters.durationSeconds) : '';
+  const durationSelectionValid = hasSelectableVideoDuration(
+    quote,
+    draft.generationParameters,
+  );
   const updateParameters = (next: EditableGenerationParameters) => {
     onDraftChange({
       ...draft,
@@ -867,7 +885,7 @@ function QuoteCard({
           size="sm"
           className="h-8 rounded-full bg-brand px-3 text-xs font-semibold text-primary-foreground"
           onClick={onConfirm}
-          disabled={busy || dirty || repricing}
+          disabled={busy || dirty || repricing || !durationSelectionValid}
         >
           {busy || repricing
             ? <Loader2 className="mr-1.5 h-3.5 w-3.5 animate-spin" />
@@ -1153,6 +1171,7 @@ export function ImageCanvas() {
     setQuoteDirty(true);
     setRepricingQuoteId(quote.quoteId);
     setQuoteUpdateError(null);
+    setActionError(null);
     quoteDraftVersionRef.current += 1;
     const version = quoteDraftVersionRef.current;
     if (quoteRepriceTimerRef.current !== null) clearTimeout(quoteRepriceTimerRef.current);
@@ -1189,6 +1208,11 @@ export function ImageCanvas() {
       setActionError('当前报价正在更新，请等待重新报价完成后再确认。');
       return;
     }
+    if (!quote || quote.quoteId !== quoteId
+      || !hasSelectableVideoDuration(quote, draft.generationParameters)) {
+      setActionError('请选择 2 至 6 秒的视频时长，等待重新报价完成后再确认。');
+      return;
+    }
     const requestedWorkspaceId = workspace.workspaceId;
     const requestedConversationId = conversation.conversationId;
     setConfirmingQuoteId(quoteId);