feat(f3): add guess submission endpoint with deadline checks

lobby/views.py

@@ -11,6 +11,7 @@ from django.views.decorators.http import require_GET, require_POST
 from fupogfakta.models import (
     Category,
     GameSession,
+    Guess,
     LieAnswer,
     Player,
     Question,
@@ -398,3 +399,100 @@ def mix_answers(request: HttpRequest, code: str, round_question_id: int) -> Json
             "answers": [{"text": text} for text in deduped_answers],
         }
     )
+
+
+@require_POST
+def submit_guess(request: HttpRequest, code: str, round_question_id: int) -> JsonResponse:
+    payload = _json_body(request)
+    session_code = code.strip().upper()
+
+    player_id = payload.get("player_id")
+    selected_text = str(payload.get("selected_text", "")).strip()
+
+    if not player_id:
+        return JsonResponse({"error": "player_id is required"}, status=400)
+
+    if not selected_text or len(selected_text) > 255:
+        return JsonResponse({"error": "selected_text must be between 1 and 255 characters"}, status=400)
+
+    try:
+        session = GameSession.objects.get(code=session_code)
+    except GameSession.DoesNotExist:
+        return JsonResponse({"error": "Session not found"}, status=404)
+
+    if session.status != GameSession.Status.GUESS:
+        return JsonResponse({"error": "Guess submission is only allowed in guess phase"}, status=400)
+
+    try:
+        player = Player.objects.get(pk=player_id, session=session)
+    except Player.DoesNotExist:
+        return JsonResponse({"error": "Player not found in session"}, status=404)
+
+    try:
+        round_question = RoundQuestion.objects.get(
+            pk=round_question_id,
+            session=session,
+            round_number=session.current_round,
+        )
+    except RoundQuestion.DoesNotExist:
+        return JsonResponse({"error": "Round question not found"}, status=404)
+
+    try:
+        round_config = RoundConfig.objects.get(session=session, number=round_question.round_number)
+    except RoundConfig.DoesNotExist:
+        return JsonResponse({"error": "Round config missing"}, status=400)
+
+    guess_deadline_at = round_question.shown_at + timedelta(
+        seconds=round_config.lie_seconds + round_config.guess_seconds
+    )
+    if timezone.now() > guess_deadline_at:
+        return JsonResponse({"error": "Guess submission window has closed"}, status=400)
+
+    allowed_answers = {
+        round_question.correct_answer.strip().casefold(),
+        *(
+            text.strip().casefold()
+            for text in round_question.lies.values_list("text", flat=True)
+            if text.strip()
+        ),
+    }
+
+    selected_normalized = selected_text.casefold()
+    if selected_normalized not in allowed_answers:
+        return JsonResponse({"error": "Selected answer is not part of this round"}, status=400)
+
+    correct_normalized = round_question.correct_answer.strip().casefold()
+    fooled_player_id = None
+    if selected_normalized != correct_normalized:
+        fooled_player_id = (
+            round_question.lies.filter(text__iexact=selected_text).values_list("player_id", flat=True).first()
+        )
+
+    try:
+        guess = Guess.objects.create(
+            round_question=round_question,
+            player=player,
+            selected_text=selected_text,
+            is_correct=selected_normalized == correct_normalized,
+            fooled_player_id=fooled_player_id,
+        )
+    except IntegrityError:
+        return JsonResponse({"error": "Guess already submitted for this player"}, status=409)
+
+    return JsonResponse(
+        {
+            "guess": {
+                "id": guess.id,
+                "player_id": player.id,
+                "round_question_id": round_question.id,
+                "selected_text": guess.selected_text,
+                "is_correct": guess.is_correct,
+                "fooled_player_id": guess.fooled_player_id,
+                "created_at": guess.created_at.isoformat(),
+            },
+            "window": {
+                "guess_deadline_at": guess_deadline_at.isoformat(),
+            },
+        },
+        status=201,
+    )