Add external problem mentor workspace with guarded access

app/(main)/external-feedback/page.tsx

@@ -0,0 +1,20 @@
+"use client"
+
+import { ExternalProblemFeedback } from "@/components/external-problem-feedback"
+import { withMentorAccessGuard } from "@/components/with-mentor-access-guard"
+import { PageTransition } from "@/components/page-transition"
+import { usePageEntryAnimation } from "@/lib/use-page-entry-animation"
+
+function ExternalFeedbackPage() {
+  const shouldAnimateOnMount = usePageEntryAnimation()
+
+  return (
+    <PageTransition animateOnMount={shouldAnimateOnMount}>
+      <ExternalProblemFeedback />
+    </PageTransition>
+  )
+}
+
+export default withMentorAccessGuard(ExternalFeedbackPage, {
+  fallbackPath: "/",
+})

app/(main)/page.tsx

@@ -1,19 +1,32 @@
 "use client"
 
 import { useEffect, useMemo, useState } from "react"
+import { useRouter } from "next/navigation"
 import { ChevronDown } from "lucide-react"
 import { HeroSection } from "@/components/hero-section"
 import { VirtualizedProblemList } from "@/components/virtualized-problem-list"
 import { StreakWidget } from "@/components/streak-widget"
 import { StatsWidget } from "@/components/stats-widget"
+import {
+  AlertDialog,
+  AlertDialogAction,
+  AlertDialogCancel,
+  AlertDialogContent,
+  AlertDialogDescription,
+  AlertDialogFooter,
+  AlertDialogHeader,
+  AlertDialogTitle,
+} from "@/components/ui/alert-dialog"
 import { PageTransition } from "@/components/page-transition"
 import { problems } from "@/lib/problems"
 import { localizeCategory } from "@/lib/problems"
 import type { Difficulty, Problem } from "@/lib/problems"
 import {
+  getApiSettings,
   getSolvedProblemIds,
   subscribeToProgressUpdates,
 } from "@/lib/local-progress"
+import { isMentorConfigured as resolveMentorConfigured } from "@/lib/mentor-access"
 import { useAppLanguage } from "@/lib/use-app-language"
 import { usePageEntryAnimation } from "@/lib/use-page-entry-animation"
 import { useRestoreScroll } from "@/lib/use-restore-scroll"
@@ -49,6 +62,7 @@ function parseHomeViewState(value: unknown): HomeViewState | null {
 }
 
 export default function HomePage() {
+  const router = useRouter()
   const { language, copy } = useAppLanguage()
   const shouldAnimateOnMount = usePageEntryAnimation()
   const [viewState, setViewState] = useRestoreScroll<HomeViewState>({
@@ -62,13 +76,23 @@ export default function HomePage() {
   })
   const { selectedCategory, selectedDifficulty, sortBy } = viewState
   const [solvedIds, setSolvedIds] = useState<Set<string>>(new Set())
+  const [isMentorReady, setIsMentorReady] = useState(false)
+  const [isMentorAlertOpen, setIsMentorAlertOpen] = useState(false)
 
   useEffect(() => {
     const sync = () => setSolvedIds(getSolvedProblemIds())
     sync()
     return subscribeToProgressUpdates(sync)
   }, [])
 
+  useEffect(() => {
+    const sync = () => {
+      setIsMentorReady(resolveMentorConfigured(getApiSettings()))
+    }
+    sync()
+    return subscribeToProgressUpdates(sync)
+  }, [])
+
   const categories = useMemo(() => {
     const map = new Map<string, number>()
     for (const problem of problems) {
@@ -87,7 +111,6 @@ export default function HomePage() {
     language === "ko" ? "난이도 오름차순" : "Difficulty Ascending"
   const sortDifficultyDescLabel =
     language === "ko" ? "난이도 내림차순" : "Difficulty Descending"
-
   const difficultyRank: Record<Difficulty, number> = {
     Easy: 0,
     Medium: 1,
@@ -123,6 +146,14 @@ export default function HomePage() {
     return source.filter((problem) => problem.difficulty === difficulty).length
   }
 
+  const handleExternalFeedbackOpen = () => {
+    if (!isMentorReady) {
+      setIsMentorAlertOpen(true)
+      return
+    }
+    router.push("/external-feedback")
+  }
+
   return (
     <PageTransition animateOnMount={shouldAnimateOnMount}>
       <HeroSection />
@@ -204,10 +235,37 @@ export default function HomePage() {
             <div className="sticky top-24 flex flex-col gap-4">
               <StreakWidget />
               <StatsWidget />
+              <section className="rounded-2xl border border-border/70 bg-card p-4 shadow-sm">
+                <p className="text-sm font-semibold text-foreground">{copy.home.externalFeedbackTitle}</p>
+                <p className="mt-1 text-xs text-muted-foreground">{copy.home.externalFeedbackDescription}</p>
+                <button
+                  type="button"
+                  onClick={handleExternalFeedbackOpen}
+                  className="mt-3 inline-flex w-full items-center justify-center rounded-full bg-[#3182F6] px-4 py-2 text-sm font-semibold text-white transition-colors hover:bg-[#2870d8]"
+                >
+                  {copy.home.externalFeedbackAction}
+                </button>
+              </section>
             </div>
           </aside>
         </div>
       </main>
+      <AlertDialog open={isMentorAlertOpen} onOpenChange={setIsMentorAlertOpen}>
+        <AlertDialogContent overlayClassName="bg-black/45">
+          <AlertDialogHeader>
+            <AlertDialogTitle>{copy.problem.mentorSetupTitle}</AlertDialogTitle>
+            <AlertDialogDescription>
+              {copy.problem.mentorSetupDescription}
+            </AlertDialogDescription>
+          </AlertDialogHeader>
+          <AlertDialogFooter>
+            <AlertDialogCancel>{copy.problem.mentorSetupCancel}</AlertDialogCancel>
+            <AlertDialogAction onClick={() => router.push("/settings")}>
+              {copy.problem.mentorSetupGoToSettings}
+            </AlertDialogAction>
+          </AlertDialogFooter>
+        </AlertDialogContent>
+      </AlertDialog>
     </PageTransition>
   )
 }

app/problem/[id]/problem-page-client.tsx

@@ -37,6 +37,7 @@ import {
 } from "@/lib/local-progress";
 import { useAppLanguage } from "@/lib/use-app-language";
 import { useIsMobile } from "@/components/ui/use-mobile";
+import { isMentorConfigured as resolveMentorConfigured } from "@/lib/mentor-access";
 
 interface ProblemPageClientProps {
   problem: Problem;
@@ -90,11 +91,7 @@ export function ProblemPageClient({ problem }: ProblemPageClientProps) {
 
   useEffect(() => {
     const sync = () => {
-      const settings = getApiSettings();
-      const provider = settings.provider;
-      const hasModel = Boolean(settings.models[provider]?.trim());
-      const hasApiKey = Boolean(settings.apiKeys[provider]?.trim());
-      setIsMentorConfigured(hasModel && hasApiKey);
+      setIsMentorConfigured(resolveMentorConfigured(getApiSettings()));
     };
     sync();
     return subscribeToProgressUpdates(sync);

components/external-problem-feedback.tsx

@@ -0,0 +1,135 @@
+"use client"
+
+import { useState } from "react"
+import Editor from "@monaco-editor/react"
+import { RotateCcw } from "lucide-react"
+import {
+  ResizableHandle,
+  ResizablePanel,
+  ResizablePanelGroup,
+} from "@/components/ui/resizable"
+import { ScrollArea } from "@/components/ui/scroll-area"
+import { Input } from "@/components/ui/input"
+import { Textarea } from "@/components/ui/textarea"
+import { useIsMobile } from "@/components/ui/use-mobile"
+import { CodeAssistantChat } from "@/components/code-assistant-chat"
+import { useAppLanguage } from "@/lib/use-app-language"
+
+export function ExternalProblemFeedback() {
+  const { copy } = useAppLanguage()
+  const isMobile = useIsMobile()
+  const text = copy.externalFeedback
+  const [problemTitle, setProblemTitle] = useState("")
+  const [problemText, setProblemText] = useState("")
+  const [code, setCode] = useState("")
+
+  const normalizedProblemDescription =
+    problemText.trim() || text.chatMissingProblemContext
+  const normalizedProblemTitle = problemTitle.trim() || text.defaultProblemTitle
+  const handleReset = () => {
+    setCode("")
+  }
+
+  return (
+    <div className="h-[calc(100dvh-64px)] overflow-hidden bg-background">
+      <div className={`flex h-full ${isMobile ? "flex-col" : "flex-row"}`}>
+        <div className={`min-w-0 ${isMobile ? "h-[60dvh]" : "flex-1"}`}>
+          <ResizablePanelGroup direction={isMobile ? "vertical" : "horizontal"}>
+            <ResizablePanel defaultSize={isMobile ? 45 : 48} minSize={isMobile ? 24 : 24}>
+              <ScrollArea className="h-full border-r border-border/70">
+                <div className="space-y-4 p-6">
+                  <div>
+                    <h1 className="text-2xl font-bold text-foreground">{text.title}</h1>
+                    <p className="mt-2 text-sm text-muted-foreground">{text.description}</p>
+                  </div>
+                  <div>
+                    <label className="mb-1.5 block text-xs font-semibold text-muted-foreground">
+                      {text.titleLabel}
+                    </label>
+                    <Input
+                      value={problemTitle}
+                      onChange={(event) => setProblemTitle(event.target.value)}
+                      placeholder={text.titlePlaceholder}
+                    />
+                  </div>
+                  <div>
+                    <label className="mb-1.5 block text-xs font-semibold text-muted-foreground">
+                      {text.problemLabel}
+                    </label>
+                    <Textarea
+                      value={problemText}
+                      onChange={(event) => setProblemText(event.target.value)}
+                      placeholder={text.problemPlaceholder}
+                      className="min-h-[420px] resize-none"
+                    />
+                  </div>
+                </div>
+              </ScrollArea>
+            </ResizablePanel>
+
+            <ResizableHandle withHandle={!isMobile} />
+
+            <ResizablePanel defaultSize={isMobile ? 55 : 52} minSize={isMobile ? 24 : 26}>
+              <div className="relative flex h-full max-h-full flex-col overflow-hidden bg-background">
+                <div className="flex-shrink-0 flex items-center justify-between border-b border-border/60 px-4 py-3">
+                  <div className="flex items-center gap-2">
+                    <div className="h-3 w-3 rounded-full bg-destructive/60" />
+                    <div className="h-3 w-3 rounded-full bg-warning/60" />
+                    <div className="h-3 w-3 rounded-full bg-success/60" />
+                    <span className="ml-2 text-xs font-medium text-muted-foreground">
+                      solution.js
+                    </span>
+                  </div>
+                  <button
+                    onClick={handleReset}
+                    className="flex items-center gap-1.5 rounded-[16px] px-3 py-1.5 text-xs font-semibold text-muted-foreground transition-colors hover:bg-muted hover:text-foreground"
+                  >
+                    <RotateCcw className="h-3 w-3" />
+                    Reset
+                  </button>
+                </div>
+                <div className="min-h-0 flex-1">
+                  <Editor
+                    height="100%"
+                    defaultLanguage="javascript"
+                    value={code}
+                    onChange={(value) => setCode(value ?? "")}
+                    options={{
+                      minimap: { enabled: false },
+                      fontSize: 14,
+                      lineNumbers: "on",
+                      scrollBeyondLastLine: false,
+                      wordWrap: "on",
+                      automaticLayout: true,
+                    }}
+                  />
+                </div>
+              </div>
+            </ResizablePanel>
+          </ResizablePanelGroup>
+        </div>
+
+        <aside className={`border-l border-border/70 ${isMobile ? "h-[40dvh] w-full" : "w-[420px] flex-shrink-0"}`}>
+          <div className="flex h-full flex-col">
+            <div className="border-b border-border/70 px-4 py-3">
+              <p className="text-sm font-semibold text-foreground">{text.chatTitle}</p>
+              <p className="mt-1 text-xs text-muted-foreground">{text.chatDescription}</p>
+            </div>
+            {!problemText.trim() ? (
+              <div className="border-b border-border/70 bg-amber-50/70 px-4 py-2 text-xs font-medium text-amber-700">
+                {text.chatMissingProblem}
+              </div>
+            ) : null}
+            <div className="min-h-0 flex-1">
+              <CodeAssistantChat
+                code={code}
+                problemTitle={normalizedProblemTitle}
+                problemDescription={normalizedProblemDescription}
+              />
+            </div>
+          </div>
+        </aside>
+      </div>
+    </div>
+  )
+}

components/with-mentor-access-guard.tsx

@@ -0,0 +1,81 @@
+"use client"
+
+import { useEffect, useState, type ComponentType } from "react"
+import { useRouter } from "next/navigation"
+import {
+  AlertDialog,
+  AlertDialogAction,
+  AlertDialogCancel,
+  AlertDialogContent,
+  AlertDialogDescription,
+  AlertDialogFooter,
+  AlertDialogHeader,
+  AlertDialogTitle,
+} from "@/components/ui/alert-dialog"
+import { getApiSettings, subscribeToProgressUpdates } from "@/lib/local-progress"
+import { isMentorConfigured } from "@/lib/mentor-access"
+import { useAppLanguage } from "@/lib/use-app-language"
+
+interface MentorAccessGuardOptions {
+  fallbackPath?: string
+}
+
+export function withMentorAccessGuard<P extends object>(
+  WrappedComponent: ComponentType<P>,
+  options?: MentorAccessGuardOptions
+) {
+  const fallbackPath = options?.fallbackPath ?? "/"
+
+  const GuardedComponent = (props: P) => {
+    const router = useRouter()
+    const { copy } = useAppLanguage()
+    const [ready, setReady] = useState(false)
+    const [allowed, setAllowed] = useState(false)
+
+    useEffect(() => {
+      const sync = () => {
+        setAllowed(isMentorConfigured(getApiSettings()))
+        setReady(true)
+      }
+
+      sync()
+      return subscribeToProgressUpdates(sync)
+    }, [])
+
+    if (ready && allowed) {
+      return <WrappedComponent {...props} />
+    }
+
+    return (
+      <AlertDialog
+        open={ready && !allowed}
+        onOpenChange={(open) => {
+          if (!open) {
+            router.push(fallbackPath)
+          }
+        }}
+      >
+        <AlertDialogContent overlayClassName="bg-black/45">
+          <AlertDialogHeader>
+            <AlertDialogTitle>{copy.problem.mentorSetupTitle}</AlertDialogTitle>
+            <AlertDialogDescription>
+              {copy.problem.mentorSetupDescription}
+            </AlertDialogDescription>
+          </AlertDialogHeader>
+          <AlertDialogFooter>
+            <AlertDialogCancel onClick={() => router.push(fallbackPath)}>
+              {copy.problem.mentorSetupCancel}
+            </AlertDialogCancel>
+            <AlertDialogAction onClick={() => router.push("/settings")}>
+              {copy.problem.mentorSetupGoToSettings}
+            </AlertDialogAction>
+          </AlertDialogFooter>
+        </AlertDialogContent>
+      </AlertDialog>
+    )
+  }
+
+  GuardedComponent.displayName = `withMentorAccessGuard(${WrappedComponent.displayName ?? WrappedComponent.name ?? "Component"})`
+
+  return GuardedComponent
+}