feat: Update play page to use multiple opening detection

- Change openingData from single to array in ChessGame.tsx
- Update all opening lookups to use lookupPossibleOpenings()
- Extract move sequence from PGN for opening lookup
- Update Tutor.tsx to accept array of openings
- Add smart opening instructions based on count:
  - 1 opening: Confident identification with metadata
  - Multiple: List possibilities, suggest general principles
  - None: Focus on position without inventing names
- Pass up to 5 possible openings to LLM in all prompts

src/components/ChessGame.tsx

@@ -10,7 +10,7 @@ import { Personality } from "@/lib/personalities";
 import Header from "./Header";
 import { useTranslation } from "@/lib/i18n/useTranslation";
 import { SupportedLanguage } from "@/lib/i18n/translations";
-import { lookupOpening, OpeningMetadata } from "@/lib/openings";
+import { lookupOpening, lookupPossibleOpenings, extractMoveSequenceFromPGN, OpeningMetadata } from "@/lib/openings";
 import { GameAnalysisModal } from "./GameAnalysisModal";
 import { GameOverModal, MoveHistoryItem } from "./GameOverModal";
 import { Brain, ArrowLeft } from "lucide-react";
@@ -46,7 +46,7 @@ export default function ChessGame({ gameId, initialFen, initialPgn, initialPerso
     const [evalP2, setEvalP2] = useState<StockfishEvaluation | null>(null);
 
     // Opening Data
-    const [openingData, setOpeningData] = useState<OpeningMetadata | null>(null);
+    const [openingData, setOpeningData] = useState<OpeningMetadata[]>([]);
 
     // Tactical Analysis Data
     const [latestMissedTactics, setLatestMissedTactics] = useState<DetectedTactic[] | null>(null);
@@ -302,7 +302,7 @@ export default function ChessGame({ gameId, initialFen, initialPgn, initialPerso
         // Reset Computer State
         setComputerMove(null);
         setEvalP2(null);
-        setOpeningData(null);
+        setOpeningData([]);
 
         setIsAnalyzing(true);
         const { newFen: fenP1 } = moveResult;
@@ -337,9 +337,11 @@ export default function ChessGame({ gameId, initialFen, initialPgn, initialPerso
                     stockfish.evaluate(fenP2, stockfishDepth).then(p2Eval => {
                         setEvalP2(p2Eval);
 
-                        // 4. Opening Lookup
+                        // 4. Opening Lookup - Get multiple possible openings
-                        const opening = lookupOpening(fenP2);
+                        const currentPgn = gameRef.current.pgn();
-                        setOpeningData(opening);
+                        const moveSequence = extractMoveSequenceFromPGN(currentPgn);
+                        const possibleOpenings = lookupPossibleOpenings(moveSequence, 5);
+                        setOpeningData(possibleOpenings);
 
                         // 5. Complete the history item with computer's move data (only if we have evalP0)
                         if (partialHistoryItem && evalP0) {
@@ -364,7 +366,7 @@ export default function ChessGame({ gameId, initialFen, initialPgn, initialPerso
                                 computerMove: compResult.result.san,
                                 fenAfterComputerMove: fenP2,
                                 evalAfterComputerMove: p2Eval,
-                                opening: opening?.name,
+                                opening: possibleOpenings.length > 0 ? possibleOpenings[0].name : undefined,
                                 // Legacy fields for backward compatibility
                                 move: moveResult.result.san,
                                 evalBefore: evalP0.score,
@@ -424,8 +426,10 @@ export default function ChessGame({ gameId, initialFen, initialPgn, initialPerso
                     // Evaluate the position after computer's move
                     stockfish.evaluate(newFen, stockfishDepth).then(p2Eval => {
                         setEvalP2(p2Eval);
-                        const opening = lookupOpening(newFen);
+                        const currentPgn = gameRef.current.pgn();
-                        setOpeningData(opening);
+                        const moveSequence = extractMoveSequenceFromPGN(currentPgn);
+                        const possibleOpenings = lookupPossibleOpenings(moveSequence, 5);
+                        setOpeningData(possibleOpenings);
                         setIsAnalyzing(false);
                     }).catch(err => {
                         console.error("Post-computer-move analysis failed:", err);
@@ -453,7 +457,7 @@ export default function ChessGame({ gameId, initialFen, initialPgn, initialPerso
         setComputerMove(null);
         setEvalP0(null);
         setEvalP2(null);
-        setOpeningData(null);
+        setOpeningData([]);
         updateCapturedPieces();
     };
 
@@ -565,7 +569,7 @@ export default function ChessGame({ gameId, initialFen, initialPgn, initialPerso
                                     setComputerMove(null);
                                     setEvalP0(null);
                                     setEvalP2(null);
-                                    setOpeningData(null);
+                                    setOpeningData([]);
                                     updateCapturedPieces();
                                 }}
                                 className="flex items-center gap-1 hover:text-red-600 dark:hover:text-red-400 transition-colors"

src/components/Tutor.tsx

@@ -23,7 +23,7 @@ interface TutorProps {
     stockfish: Stockfish | null;
     evalP0: StockfishEvaluation | null;
     evalP2: StockfishEvaluation | null;
-    openingData: OpeningMetadata | null;
+    openingData: OpeningMetadata[];
     missedTactics: DetectedTactic[] | null;
     onAnalysisComplete: () => void;
     apiKey: string | null;
@@ -168,19 +168,34 @@ CRITICAL RULES:
 
                 // Opening Instruction
                 let openingInstruction = "";
-                if (openingData) {
+                if (openingData && openingData.length > 0) {
-                    openingInstruction = `
+                    if (openingData.length === 1) {
-OPENING IDENTIFIED: ${openingData.name} (${openingData.eco}).
+                        // Single opening identified
-You MUST mention the opening name.
+                        const opening = openingData[0];
+                        openingInstruction = `
+OPENING IDENTIFIED: ${opening.name} (${opening.eco}).
+You can confidently reference this opening and its typical plans.
 You can use this metadata to explain the position:
-- Strengths (White): ${openingData.meta?.strengths_white?.join(", ")}
+- Strengths (White): ${opening.meta?.strengths_white?.join(", ") || 'N/A'}
-- Weaknesses (White): ${openingData.meta?.weaknesses_white?.join(", ")}
+- Weaknesses (White): ${opening.meta?.weaknesses_white?.join(", ") || 'N/A'}
-- Strengths (Black): ${openingData.meta?.strengths_black?.join(", ")}
+- Strengths (Black): ${opening.meta?.strengths_black?.join(", ") || 'N/A'}
-- Weaknesses (Black): ${openingData.meta?.weaknesses_black?.join(", ")}
+- Weaknesses (Black): ${opening.meta?.weaknesses_black?.join(", ") || 'N/A'}
-                    `;
+                        `;
+                    } else {
+                        // Multiple possible openings
+                        const openingList = openingData.map(o => `- ${o.name} (${o.eco})`).join('\n');
+                        openingInstruction = `
+OPENING CONTEXT:
+Multiple openings are possible from this position:
+${openingList}
+
+INSTRUCTIONS:
+- Do NOT claim a specific opening is being played yet
+- You may mention "this could lead to..." or "typical of openings like..."
+- Focus on general principles rather than specific opening theory
+                        `;
+                    }
                 } else {
-                    // openingInstruction = "NO opening identified. Do NOT invent an opening name. Do NOT mention openings.";
-                    // Relaxed instruction to allow general commentary if no specific opening is found, but still forbid inventing names.
                     openingInstruction = "NO specific opening identified from database. Do NOT invent an opening name. Focus on the position.";
                 }
 
@@ -299,7 +314,7 @@ Current Position Data:
 - Best Move: ${evaluation?.bestMove}
 - Evaluation: ${evaluation?.score ?? 'N/A'} centipawns ${evaluation?.score !== undefined ? (evaluation.score > 0 ? '(White is better)' : evaluation.score < 0 ? '(Black is better)' : '(Equal)') : ''}
 - Mate in: ${evaluation?.mate || 'None'}
-- Opening: ${openingData ? `${openingData.name} (${openingData.eco})` : 'Unknown/Midgame'}
+- Possible Openings: ${openingData && openingData.length > 0 ? openingData.map(o => `${o.name} (${o.eco})`).join(', ') : 'Unknown/Midgame'}
 
 INSTRUCTIONS:
 - Tell them the best move clearly (e.g., "The best move is e2-e4" or "You should play Nf3")
@@ -323,7 +338,7 @@ Current Position Data:
 - Best Move: ${evaluation?.bestMove}
 - Evaluation: ${evaluation?.score ?? 'N/A'} centipawns ${evaluation?.score !== undefined ? (evaluation.score > 0 ? '(White is better)' : evaluation.score < 0 ? '(Black is better)' : '(Equal)') : ''}
 - Mate in: ${evaluation?.mate || 'None'}
-- Opening: ${openingData ? `${openingData.name} (${openingData.eco})` : 'Unknown/Midgame'}
+- Possible Openings: ${openingData && openingData.length > 0 ? openingData.map(o => `${o.name} (${o.eco})`).join(', ') : 'Unknown/Midgame'}
 
 INSTRUCTIONS:
 - Give a HELPFUL hint without revealing the exact move (unless they specifically ask for it)
@@ -342,7 +357,7 @@ Current Position Context:
 - Evaluation: ${evaluation?.score ?? 'N/A'} centipawns ${evaluation?.score !== undefined ? (evaluation.score > 0 ? '(White is better)' : evaluation.score < 0 ? '(Black is better)' : '(Equal)') : ''}
 - Best Move: ${evaluation?.bestMove ?? 'N/A'}
 - Mate in: ${evaluation?.mate || 'None'}
-- Opening: ${openingData ? `${openingData.name} (${openingData.eco})` : 'Unknown/Midgame'}
+- Possible Openings: ${openingData && openingData.length > 0 ? openingData.map(o => `${o.name} (${o.eco})`).join(', ') : 'Unknown/Midgame'}
 
 INSTRUCTIONS:
 - Answer the user's question based on the CURRENT position data above