Fix 法规对话

backend/app/api/routes/agent.py

@@ -2,7 +2,6 @@
 
 from __future__ import annotations
 
-import asyncio
 import json
 from typing import AsyncGenerator, List, Optional
 
@@ -20,6 +19,7 @@ from app.api.models import (
     SessionInfo,
 )
 from app.config.settings import settings
+from app.shared.async_utils import iter_in_thread
 from app.shared.bootstrap import get_agent_conversation_service, get_conversation_store
 # Keep route handlers close to their transport-layer wiring for easier auditing.
 
@@ -101,14 +101,13 @@ async def chat_stream_get(
                 top_k=settings.rag_top_k,
             )
             yield f"event: session\ndata: {json.dumps({'session_id': session_id_})}\n\n"
-            for event_data in event_stream:
+            async for event_data in iter_in_thread(event_stream):
                 event_type = event_data.get("event", "content")
                 data = event_data.get("data", "")
                 if isinstance(data, (dict, list)):
                     yield f"event: {event_type}\ndata: {json.dumps(data, ensure_ascii=False)}\n\n"
                 else:
                     yield f"event: {event_type}\ndata: {data}\n\n"
-                await asyncio.sleep(0)
         except Exception as exc:
             yield f"event: error\ndata: {str(exc)}\n\n"
 

backend/app/api/routes/rag.py

@@ -2,7 +2,6 @@
 
 from __future__ import annotations
 
-import asyncio
 import json
 from typing import AsyncGenerator
 
@@ -11,6 +10,7 @@ from fastapi.responses import StreamingResponse
 
 from app.config.settings import settings
 from app.schemas.rag import RagChatRequest, QuickQuestionsResponse, QuickQuestion
+from app.shared.async_utils import iter_in_thread
 from app.shared.bootstrap import get_agent_conversation_service
 
 
@@ -29,7 +29,7 @@ _DEFAULT_QUICK_QUESTIONS = [
 @router.post("/chat")
 async def rag_chat(request: RagChatRequest):
     """Stream RAG Q&A using the real agent service."""
-    _, event_stream = get_agent_conversation_service().stream_chat(
+    session_id, event_stream = get_agent_conversation_service().stream_chat(
         query=request.query,
         session_id=request.session_id,
         filters=request.filters,
@@ -38,7 +38,11 @@ async def rag_chat(request: RagChatRequest):
 
     async def generate() -> AsyncGenerator[str, None]:
         """Translate agent SSE events to rag format."""
-        for event in event_stream:
+        yield (
+            "event: message\n"
+            f"data: {json.dumps({'type': 'session', 'session_id': session_id}, ensure_ascii=False)}\n\n"
+        )
+        async for event in iter_in_thread(event_stream):
             event_type = event.get("event", "")
             data = event.get("data", "")
             if event_type == "sources":
@@ -69,14 +73,18 @@ async def rag_chat(request: RagChatRequest):
             elif event_type == "done":
                 yield (
                     "event: message\n"
-                    f"data: {json.dumps({'type': 'done'}, ensure_ascii=False)}\n\n"
+                    f"data: {json.dumps({'type': 'done', 'session_id': session_id}, ensure_ascii=False)}\n\n"
                 )
             elif event_type == "status":
                 yield (
                     "event: message\n"
                     f"data: {json.dumps({'type': 'status', 'text': data}, ensure_ascii=False)}\n\n"
                 )
-            await asyncio.sleep(0)
+            elif event_type == "error":
+                yield (
+                    "event: message\n"
+                    f"data: {json.dumps({'type': 'error', 'text': str(data)}, ensure_ascii=False)}\n\n"
+                )
 
     return StreamingResponse(
         generate(),

backend/app/application/knowledge/services.py

@@ -7,20 +7,75 @@ from app.domain.retrieval.ports import Reranker
 # Keep orchestration logic centralized so use-case flow stays easy to trace.
 
 
+def _reciprocal_rank_fusion(
+    ranked_lists: list[list[RetrievedChunk]], k: int = 60
+) -> list[RetrievedChunk]:
+    """Merge multiple ranked lists with Reciprocal Rank Fusion.
+
+    Score for chunk c = sum over lists of 1 / (k + rank(c)).
+    A chunk appearing in multiple lists gets a higher fused score.
+    """
+    scores: dict[str, float] = {}
+    chunk_map: dict[str, RetrievedChunk] = {}
+
+    for ranked in ranked_lists:
+        for rank, chunk in enumerate(ranked):
+            key = chunk.chunk_id
+            scores[key] = scores.get(key, 0.0) + 1.0 / (k + rank + 1)
+            chunk_map[key] = chunk
+
+    sorted_keys = sorted(scores, key=lambda ck: scores[ck], reverse=True)
+    return [
+        RetrievedChunk(
+            chunk_id=chunk_map[ck].chunk_id,
+            doc_id=chunk_map[ck].doc_id,
+            doc_name=chunk_map[ck].doc_name,
+            content=chunk_map[ck].content,
+            score=scores[ck],
+            section_title=chunk_map[ck].section_title,
+            page_number=chunk_map[ck].page_number,
+            metadata=chunk_map[ck].metadata,
+        )
+        for ck in sorted_keys
+    ]
+
+
 class KnowledgeRetrievalService:
     """Provide the Knowledge Retrieval Service service."""
 
-    def __init__(self, *, retriever: Retriever, reranker: Reranker | None = None, reranker_top_k: int = 5) -> None:
+    def __init__(
+        self,
+        *,
+        retriever: Retriever,
+        bm25_retriever=None,
+        reranker: Reranker | None = None,
+        reranker_top_k: int = 5,
+    ) -> None:
         """Initialize the Knowledge Retrieval Service instance."""
         self.retriever = retriever
+        self.bm25_retriever = bm25_retriever
         self.reranker = reranker
         self.reranker_top_k = reranker_top_k
 
     def retrieve(self, *, query: str, top_k: int, filters: str | None = None) -> list[RetrievedChunk]:
-        """Retrieve and optionally rerank chunks for a query."""
+        """Retrieve and optionally rerank chunks for a query.
-        candidate_k = top_k if self.reranker is None else max(top_k * 4, 20)
+
+        When a BM25 retriever is available, combines dense + sparse results
+        via Reciprocal Rank Fusion before optional reranking.
+        """
+        use_hybrid = self.bm25_retriever is not None and getattr(self.bm25_retriever, "available", False)
+        candidate_k = max(top_k * 4, 20) if (self.reranker is not None or use_hybrid) else top_k
+
         retrieval_query = RetrievalQuery(query=query, top_k=candidate_k, filters=filters)
-        candidates = self.retriever.retrieve(retrieval_query)
+        dense_results = self.retriever.retrieve(retrieval_query)
+
+        if use_hybrid:
+            bm25_results = self.bm25_retriever.retrieve(query, top_k=candidate_k, filters=filters)
+            candidates = _reciprocal_rank_fusion([dense_results, bm25_results])
+        else:
+            candidates = dense_results
+
         if self.reranker and candidates:
             return self.reranker.rerank(query, candidates, top_k=self.reranker_top_k)
+
         return candidates[:top_k]

backend/app/infrastructure/llm/openai_compatible_answer_generator.py

@@ -12,7 +12,6 @@ from app.services.llm.llm_factory import get_llm_client
 # Keep adapter behavior explicit so integration details remain easy to audit.
 
 
-
 PROMPT_TEMPLATES = {
     "default": "你是法规知识问答助手。请仅依据提供的上下文回答；如果上下文不足，明确说明。",
     "compliance_qa": "你是法规合规问答助手。优先引用给定法规原文，回答要准确、克制，并注明依据来源。",
@@ -21,6 +20,17 @@ PROMPT_TEMPLATES = {
 
 class OpenAICompatibleAnswerGenerator(AnswerGenerator):
     """Represent the Open A I Compatible Answer Generator type."""
+
+    @staticmethod
+    def _estimate_tokens(text: str) -> int:
+        """Estimate token count for mixed Chinese/English text.
+
+        Chinese chars are ~1.5 chars/token; ASCII is ~4 chars/token.
+        """
+        chinese = sum(1 for c in text if "一" <= c <= "鿿")
+        other = len(text) - chinese
+        return int(chinese / 1.5 + other / 4) + 1
+
     def _build_messages(
         self,
         *,
@@ -40,9 +50,12 @@ class OpenAICompatibleAnswerGenerator(AnswerGenerator):
                 f"页码: {chunk.page_number}\n"
                 f"内容: {chunk.content}"
             )
-            context_tokens += len(block)
+            block_tokens = self._estimate_tokens(block)
+            if context_tokens + block_tokens > settings.rag_max_context_tokens:
+                break
+            context_tokens += block_tokens
             context_blocks.append(block)
-        context = "\n\n".join(context_blocks)[: settings.rag_max_context_tokens * 4]
+        context = "\n\n".join(context_blocks)
         messages = [{"role": "system", "content": system_prompt}]
         for item in history or []:
             messages.append({"role": item["role"], "content": item["content"]})
@@ -52,7 +65,7 @@ class OpenAICompatibleAnswerGenerator(AnswerGenerator):
                 "content": f"问题：{query}\n\n参考上下文：\n{context}\n\n请在回答后给出简要引用编号。",
             }
         )
-        return messages, min(context_tokens, settings.rag_max_context_tokens)
+        return messages, context_tokens
 
     def _sources(self, chunks: list[RetrievedChunk]) -> list[AnswerSource]:
         """Handle sources for this module for the Open A I Compatible Answer Generator instance."""
@@ -98,7 +111,7 @@ class OpenAICompatibleAnswerGenerator(AnswerGenerator):
             latency_ms=latency_ms,
             retrieved_count=len(retrieved_chunks),
             context_tokens=context_tokens,
-            truncated=False,
+            truncated=len(retrieved_chunks) > len(messages),
             error=response.error,
         )
 
@@ -124,15 +137,18 @@ class OpenAICompatibleAnswerGenerator(AnswerGenerator):
         yield {"event": "sources", "data": sources}
         client = get_llm_client(provider=provider or settings.llm_provider, model=model or settings.llm_model)
         answer_parts: list[str] = []
-        if hasattr(client, "stream_chat"):
+        try:
-            for chunk in client.stream_chat(messages):
+            if hasattr(client, "stream_chat"):
-                answer_parts.append(chunk)
+                for chunk in client.stream_chat(messages):
-                yield {"event": "content", "data": chunk}
+                    answer_parts.append(chunk)
-        else:
+                    yield {"event": "content", "data": chunk}
-            response = client.chat(messages)
+            else:
-            answer_parts.append(response.content)
+                response = client.chat(messages)
-            yield {"event": "content", "data": response.content}
+                answer_parts.append(response.content)
-        full_answer = "".join(answer_parts)
+                yield {"event": "content", "data": response.content}
+        except Exception as exc:
+            yield {"event": "error", "data": str(exc)}
+            return
         yield {
             "event": "done",
             "data": {

backend/app/infrastructure/vectorstore/bm25_retriever.py

@@ -0,0 +1,149 @@
+"""BM25 sparse retriever backed by the existing Milvus collection.
+
+Falls back to no-op if rank_bm25 or jieba is not installed.
+The index is built lazily on first query and can be refreshed after
+new documents are ingested by calling refresh().
+"""
+
+from __future__ import annotations
+
+import logging
+import threading
+from typing import TYPE_CHECKING
+
+from app.domain.retrieval import RetrievedChunk
+
+if TYPE_CHECKING:
+    from app.infrastructure.vectorstore.milvus_vector_index import MilvusVectorIndex
+
+logger = logging.getLogger(__name__)
+
+try:
+    from rank_bm25 import BM25Okapi
+    import jieba
+
+    jieba.setLogLevel(logging.WARNING)
+    _BM25_AVAILABLE = True
+except ImportError:
+    _BM25_AVAILABLE = False
+    logger.warning("rank_bm25 or jieba not installed – BM25 retrieval disabled. Run: pip install rank-bm25 jieba")
+
+
+def _tokenize(text: str) -> list[str]:
+    """Tokenize Chinese/mixed text with jieba."""
+    return list(jieba.cut(text))
+
+
+class BM25Retriever:
+    """Sparse BM25 retriever that indexes chunks stored in Milvus.
+
+    Thread-safe: the index is protected by a lock so concurrent requests
+    during the initial build do not race.
+    """
+
+    def __init__(self, vector_index: "MilvusVectorIndex") -> None:
+        self._vector_index = vector_index
+        self._lock = threading.Lock()
+        self._index: "BM25Okapi | None" = None
+        self._chunks: list[RetrievedChunk] = []
+
+    @property
+    def available(self) -> bool:
+        return _BM25_AVAILABLE
+
+    def _load_all_chunks(self) -> list[RetrievedChunk]:
+        """Fetch all chunk records from Milvus (no vectors needed)."""
+        try:
+            rows = self._vector_index.collection.query(
+                expr='doc_id != ""',
+                output_fields=["id", "doc_id", "doc_name", "content", "section_title", "page_number"],
+                limit=16384,
+            )
+        except Exception:
+            logger.exception("BM25Retriever: failed to fetch chunks from Milvus")
+            return []
+        return [
+            RetrievedChunk(
+                chunk_id=str(row.get("id", "")),
+                doc_id=str(row.get("doc_id", "")),
+                doc_name=str(row.get("doc_name", "")),
+                content=str(row.get("content", "")),
+                score=0.0,
+                section_title=str(row.get("section_title", "")),
+                page_number=int(row.get("page_number") or 0),
+                metadata={},
+            )
+            for row in rows
+            if row.get("content")
+        ]
+
+    def _ensure_built(self) -> None:
+        if self._index is not None:
+            return
+        with self._lock:
+            if self._index is not None:
+                return
+            self._build()
+
+    def _build(self) -> None:
+        logger.info("BM25Retriever: building index …")
+        chunks = self._load_all_chunks()
+        if not chunks:
+            logger.warning("BM25Retriever: no chunks found, index is empty")
+            self._chunks = []
+            self._index = BM25Okapi([[]])
+            return
+        tokenized = [_tokenize(c.content) for c in chunks]
+        self._chunks = chunks
+        self._index = BM25Okapi(tokenized)
+        logger.info("BM25Retriever: index built with %d chunks", len(chunks))
+
+    def refresh(self) -> None:
+        """Rebuild the index (call after new documents are ingested)."""
+        with self._lock:
+            self._index = None
+            self._chunks = []
+            self._build()
+
+    def retrieve(self, query: str, top_k: int, filters: str | None = None) -> list[RetrievedChunk]:
+        """Return top_k chunks ranked by BM25 score."""
+        if not _BM25_AVAILABLE:
+            return []
+        self._ensure_built()
+        if not self._chunks:
+            return []
+
+        tokens = _tokenize(query)
+        scores = self._index.get_scores(tokens)  # type: ignore[union-attr]
+
+        # Pair and sort descending by score
+        ranked = sorted(
+            ((float(scores[i]), self._chunks[i]) for i in range(len(self._chunks))),
+            key=lambda x: x[0],
+            reverse=True,
+        )
+
+        results: list[RetrievedChunk] = []
+        for score, chunk in ranked[: top_k * 2]:
+            if score <= 0:
+                break
+            # Apply simple regulation_type filter if provided
+            if filters and chunk.metadata.get("regulation_type"):
+                types = [t.strip() for t in filters.split(",")]
+                if chunk.metadata.get("regulation_type") not in types:
+                    continue
+            results.append(
+                RetrievedChunk(
+                    chunk_id=chunk.chunk_id,
+                    doc_id=chunk.doc_id,
+                    doc_name=chunk.doc_name,
+                    content=chunk.content,
+                    score=score,
+                    section_title=chunk.section_title,
+                    page_number=chunk.page_number,
+                    metadata=chunk.metadata,
+                )
+            )
+            if len(results) >= top_k:
+                break
+        return results

backend/app/shared/async_utils.py

@@ -0,0 +1,38 @@
+"""Async utility helpers for bridging sync generators to async FastAPI routes."""
+
+from __future__ import annotations
+
+import asyncio
+import threading
+from typing import AsyncGenerator, Generator, TypeVar
+
+T = TypeVar("T")
+
+_SENTINEL = object()
+
+
+async def iter_in_thread(sync_gen: Generator[T, None, None]) -> AsyncGenerator[T, None]:
+    """Yield items from a synchronous generator without blocking the event loop.
+
+    Runs the generator in a daemon thread, forwarding items via an asyncio.Queue.
+    Use this to wrap blocking LLM streaming generators inside async FastAPI routes.
+    """
+    loop = asyncio.get_running_loop()
+    queue: asyncio.Queue = asyncio.Queue(maxsize=32)
+
+    def _drain() -> None:
+        try:
+            for item in sync_gen:
+                future = asyncio.run_coroutine_threadsafe(queue.put(item), loop)
+                future.result()
+        finally:
+            asyncio.run_coroutine_threadsafe(queue.put(_SENTINEL), loop).result()
+
+    thread = threading.Thread(target=_drain, daemon=True)
+    thread.start()
+
+    while True:
+        item = await queue.get()
+        if item is _SENTINEL:
+            break
+        yield item  # type: ignore[misc]

backend/app/shared/bootstrap.py

@@ -19,6 +19,7 @@ from app.infrastructure.storage.json_document_repository import JsonDocumentRepo
 from app.infrastructure.storage.minio_binary_store import MinioDocumentBinaryStore
 from app.infrastructure.storage.postgres_document_repository import PostgresDocumentRepository
 from app.infrastructure.storage.postgres_parse_artifact_store import PostgresParseArtifactStore
+from app.infrastructure.vectorstore.bm25_retriever import BM25Retriever
 from app.infrastructure.vectorstore.dense_retriever import DenseRetriever
 from app.infrastructure.vectorstore.milvus_vector_index import MilvusVectorIndex
 from app.infrastructure.vectorstore.cross_encoder_reranker import OpenAICompatibleReranker
@@ -87,6 +88,13 @@ def get_reranker():
     return None
 
 
+@lru_cache
+def get_bm25_retriever() -> BM25Retriever | None:
+    """Return BM25 retriever if rank_bm25 + jieba are installed, else None."""
+    retriever = BM25Retriever(vector_index=get_vector_index())
+    return retriever if retriever.available else None
+
+
 @lru_cache
 def get_retrieval_service() -> KnowledgeRetrievalService:
     """Return retrieval service."""
@@ -96,6 +104,7 @@ def get_retrieval_service() -> KnowledgeRetrievalService:
     )
     return KnowledgeRetrievalService(
         retriever=retriever,
+        bm25_retriever=get_bm25_retriever(),
         reranker=get_reranker(),
         reranker_top_k=settings.reranker_top_k,
     )

frontend/src/api/index.ts

@@ -44,6 +44,7 @@ export interface SSEMessage {
   type: string;
   text?: string;
   docs?: RetrievedDoc[];
+  session_id?: string;
 }
 
 export async function streamSSE<TMessage extends SSEMessage>(

frontend/src/api/rag.ts

@@ -38,7 +38,14 @@ function parseSSEChunk(raw: string, onMessage: (data: SSEMessage) => void) {
     const joined = dataLines.join('\n');
     if (!joined) continue;
 
-    if (eventName === 'sources') {
+    // /agent/chat/stream uses named events (sources, content, done, error, session, status)
+    // /rag/chat wraps everything in event:message with type in JSON body — handle both
+    if (eventName === 'session') {
+      try {
+        const payload = JSON.parse(joined) as Record<string, unknown>;
+        onMessage({ type: 'session', session_id: String(payload.session_id ?? '') });
+      } catch { /* ignore */ }
+    } else if (eventName === 'sources') {
       try {
         const docs = JSON.parse(joined) as Array<Record<string, unknown>>;
         onMessage({
@@ -53,17 +60,26 @@ function parseSSEChunk(raw: string, onMessage: (data: SSEMessage) => void) {
             download_url: doc.doc_id ? `${AGENT_API_BASE}/documents/download/${String(doc.doc_id)}` : undefined,
           })),
         });
-      } catch {
+      } catch { /* ignore */ }
-        // Ignore malformed source payloads.
-      }
     } else if (eventName === 'content') {
       onMessage({ type: 'chunk', text: joined });
     } else if (eventName === 'done') {
-      onMessage({ type: 'done', text: joined });
+      try {
+        const payload = JSON.parse(joined) as Record<string, unknown>;
+        onMessage({ type: 'done', session_id: payload.session_id ? String(payload.session_id) : undefined });
+      } catch {
+        onMessage({ type: 'done' });
+      }
     } else if (eventName === 'error') {
       onMessage({ type: 'error', text: joined });
     } else if (eventName === 'status') {
       onMessage({ type: 'status', text: joined });
+    } else if (eventName === 'message') {
+      // /rag/chat format: event:message + JSON body with type field
+      try {
+        const payload = JSON.parse(joined) as SSEMessage;
+        onMessage(payload);
+      } catch { /* ignore */ }
     }
   }
 }
@@ -74,7 +90,9 @@ export async function ragChat(
   onMessage: (data: SSEMessage) => void,
   onError?: (error: Error) => void,
   onComplete?: () => void,
-  filters?: string
+  filters?: string,
+  sessionId?: string,
+  signal?: AbortSignal,
 ): Promise<void> {
   try {
     const response = await fetch(`${AGENT_API_BASE}/agent/chat/stream`, {
@@ -83,7 +101,13 @@ export async function ragChat(
         'Content-Type': 'application/json',
         Accept: 'text/event-stream',
       },
-      body: JSON.stringify({ query, top_k: topK, ...(filters ? { filters } : {}) }),
+      body: JSON.stringify({
+        query,
+        top_k: topK,
+        ...(filters ? { filters } : {}),
+        ...(sessionId ? { session_id: sessionId } : {}),
+      }),
+      signal,
     });
 
     if (!response.ok || !response.body) {
@@ -112,6 +136,7 @@ export async function ragChat(
       onComplete();
     }
   } catch (error) {
+    if (error instanceof DOMException && error.name === 'AbortError') return;
     if (onError) {
       onError(error instanceof Error ? error : new Error(String(error)));
     }

frontend/src/pages/RagChat/RagChatPage.tsx

@@ -1,4 +1,4 @@
-import React, { useEffect, useRef, useState } from 'react';
+import React, { useCallback, useEffect, useRef, useState } from 'react';
 import { useTheme } from '../../contexts';
 import type { ChatMessage, RetrievalData } from '../../types';
 import { getQuickQuestions, ragChat } from '../../api/rag';
@@ -19,6 +19,7 @@ export const RagChatPage: React.FC = () => {
   const { theme } = useTheme();
   const nextMessageIdRef = useRef(1);
   const [messages, setMessages] = useState<ChatMessage[]>([]);
+  // retrievals: right-panel shows sources of the most recent assistant reply
   const [retrievals, setRetrievals] = useState<RetrievalData[]>([]);
   const [input, setInput] = useState<string>('');
   const [loading, setLoading] = useState<boolean>(false);
@@ -27,62 +28,60 @@ export const RagChatPage: React.FC = () => {
   const [quickQuestions, setQuickQuestions] = useState<string[]>(ragQuickQuestionsDefault);
   const [filterRegulationType, setFilterRegulationType] = useState<string>('');
   const [highlightedSourceIdx, setHighlightedSourceIdx] = useState<number | null>(null);
+  const [sessionId, setSessionId] = useState<string | undefined>();
+
+  // Auto-scroll ref
+  const messagesEndRef = useRef<HTMLDivElement>(null);
+  // AbortController for cancelling in-flight requests
+  const abortRef = useRef<AbortController | null>(null);
 
   function nextMessageId() {
-    const currentId = nextMessageIdRef.current;
+    const id = nextMessageIdRef.current;
     nextMessageIdRef.current += 1;
-    return currentId;
+    return id;
   }
 
+  // Scroll to bottom whenever messages change
+  useEffect(() => {
+    messagesEndRef.current?.scrollIntoView({ behavior: 'smooth' });
+  }, [messages]);
+
   async function loadQuickQuestions() {
     try {
       const response = await getQuickQuestions();
       setQuickQuestions(response.questions.map(q => q.question));
-    } catch (error) {
+    } catch {
-      console.error('Failed to load quick questions:', error);
+      // keep defaults
     }
   }
 
   useEffect(() => {
-    const timerId = window.setTimeout(() => {
+    const timerId = window.setTimeout(() => { void loadQuickQuestions(); }, 0);
-      void loadQuickQuestions();
-    }, 0);
     return () => window.clearTimeout(timerId);
   }, []);
 
-  const sendMessage = (text: string) => {
+  /**
-    if (!text.trim()) return;
+   * Core query executor — shared by sendMessage and regenerateLastAnswer.
+   * Manages session_id, AbortController, SSE parsing, and state updates.
+   */
+  const executeQuery = useCallback((text: string) => {
+    // Cancel any in-flight request
+    abortRef.current?.abort();
+    abortRef.current = new AbortController();
 
-    const userMsg = { id: nextMessageId(), role: 'user' as const, content: text };
-    setMessages((prev) => [...prev, userMsg]);
-    setInput('');
-    setLoading(true);
-    setRetrievals([]);
-    setHighlightedSourceIdx(null);
-
-    let currentResponse = '';
     const activeFilters = filterRegulationType.trim() || undefined;
+    let currentResponse = '';
+    // Capture the assistant message id so we can attach sources later
+    let assistantMsgId: number | null = null;
 
     void ragChat(
       text,
       5,
-      (data: unknown) => {
+      (data) => {
-        const sseData = data as {
+        if (data.type === 'session' && data.session_id) {
-          type: string;
+          setSessionId(data.session_id);
-          text?: string;
+        } else if (data.type === 'retrieved' && data.docs) {
-          docs?: Array<{
+          const docs: RetrievalData[] = data.docs.map(d => ({
-            id: string;
-            score: number;
-            preview: string;
-            doc_name: string;
-            clause: string;
-            doc_id?: string;
-            download_url?: string;
-          }>;
-        };
-
-        if (sseData.type === 'retrieved' && sseData.docs) {
-          const retrievedDocs: RetrievalData[] = sseData.docs.map(d => ({
             id: parseInt(d.id.replace('chunk-', ''), 10) || 1,
             file: d.doc_name,
             clause: d.clause,
@@ -91,125 +90,98 @@ export const RagChatPage: React.FC = () => {
             docId: d.doc_id,
             downloadUrl: d.download_url,
           }));
-          setRetrievals(retrievedDocs);
+          setRetrievals(docs);
-        } else if (sseData.type === 'chunk' && sseData.text) {
+          // Attach sources to the assistant message once we know its id
-          currentResponse += sseData.text;
+          if (assistantMsgId !== null) {
-          setMessages((prev) => {
+            setMessages(prev => prev.map(m =>
-            const lastMsg = prev[prev.length - 1];
+              m.id === assistantMsgId ? { ...m, sources: docs } : m
-            if (lastMsg?.role === 'assistant') {
+            ));
-              return [...prev.slice(0, -1), { ...lastMsg, content: currentResponse }];
+          }
+        } else if (data.type === 'chunk' && data.text) {
+          currentResponse += data.text;
+          setMessages(prev => {
+            const last = prev[prev.length - 1];
+            if (last?.role === 'assistant' && last.id === assistantMsgId) {
+              return [...prev.slice(0, -1), { ...last, content: currentResponse }];
             }
-            return [...prev, { id: nextMessageId(), role: 'assistant' as const, content: currentResponse }];
+            // First chunk: create assistant message
+            const newId = nextMessageId();
+            assistantMsgId = newId;
+            return [...prev, { id: newId, role: 'assistant' as const, content: currentResponse }];
           });
-        } else if (sseData.type === 'done') {
+        } else if (data.type === 'done') {
+          if (data.session_id) setSessionId(data.session_id);
           setLoading(false);
-        } else if (sseData.type === 'error') {
+        } else if (data.type === 'error') {
           setLoading(false);
+          setMessages(prev => [
+            ...prev,
+            { id: nextMessageId(), role: 'assistant' as const, content: '抱歉，生成回答时出错，请稍后再试。' },
+          ]);
         }
       },
-      (error: Error) => {
+      (error) => {
         console.error('RAG chat error:', error);
         setLoading(false);
-        setMessages((prev) => [
+        setMessages(prev => [
           ...prev,
-          { id: nextMessageId(), role: 'assistant' as const, content: '抱歉，连接服务器时出错，请稍后再试。' }
+          { id: nextMessageId(), role: 'assistant' as const, content: '抱歉，连接服务器时出错，请稍后再试。' },
         ]);
       },
-      () => {
+      () => { setLoading(false); },
-        setLoading(false);
+      activeFilters,
-      },
+      sessionId,
-      activeFilters
+      abortRef.current.signal,
     );
-  };
+  // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [filterRegulationType, sessionId]);
 
-  const clearMessages = () => {
+  const sendMessage = (text: string) => {
-    setMessages([]);
+    if (!text.trim() || loading) return;
+    setMessages(prev => [...prev, { id: nextMessageId(), role: 'user' as const, content: text }]);
+    setInput('');
+    setLoading(true);
     setRetrievals([]);
-    setShowClearConfirm(false);
+    setHighlightedSourceIdx(null);
+    executeQuery(text);
   };
 
   const regenerateLastAnswer = () => {
-    if (messages.length < 2) return;
+    if (loading) return;
-    const lastUserMsg = messages.filter((m) => m.role === 'user').pop();
+    const lastUserMsg = [...messages].reverse().find(m => m.role === 'user');
     if (!lastUserMsg) return;
-
+    // Remove the last assistant message
+    setMessages(prev => {
+      const lastAssistantIdx = [...prev].reverse().findIndex(m => m.role === 'assistant');
+      if (lastAssistantIdx === -1) return prev;
+      const idx = prev.length - 1 - lastAssistantIdx;
+      return [...prev.slice(0, idx)];
+    });
     setLoading(true);
-    setMessages((prev) => [...prev.slice(0, -1)]);
     setRetrievals([]);
     setHighlightedSourceIdx(null);
+    executeQuery(lastUserMsg.content);
+  };
 
-    let currentResponse = '';
+  const clearMessages = () => {
-    const activeFilters = filterRegulationType.trim() || undefined;
+    abortRef.current?.abort();
-
+    setMessages([]);
-    void ragChat(
+    setRetrievals([]);
-      lastUserMsg.content,
+    setSessionId(undefined);
-      5,
+    setShowClearConfirm(false);
-      (data: unknown) => {
+    setLoading(false);
-        const sseData = data as {
-          type: string;
-          text?: string;
-          docs?: Array<{
-            id: string;
-            score: number;
-            preview: string;
-            doc_name: string;
-            clause: string;
-            doc_id?: string;
-            download_url?: string;
-          }>;
-        };
-
-        if (sseData.type === 'retrieved' && sseData.docs) {
-          const retrievedDocs: RetrievalData[] = sseData.docs.map(d => ({
-            id: parseInt(d.id.replace('chunk-', ''), 10) || 1,
-            file: d.doc_name,
-            clause: d.clause,
-            score: d.score,
-            content: d.preview,
-            docId: d.doc_id,
-            downloadUrl: d.download_url,
-          }));
-          setRetrievals(retrievedDocs);
-        } else if (sseData.type === 'chunk' && sseData.text) {
-          currentResponse += sseData.text;
-          setMessages((prev) => {
-            const lastMsg = prev[prev.length - 1];
-            if (lastMsg?.role === 'assistant') {
-              return [...prev.slice(0, -1), { ...lastMsg, content: currentResponse }];
-            }
-            return [...prev, { id: nextMessageId(), role: 'assistant' as const, content: currentResponse }];
-          });
-        } else if (sseData.type === 'done') {
-          setLoading(false);
-        }
-      },
-      (error: Error) => {
-        console.error('RAG chat error:', error);
-        setLoading(false);
-        setMessages((prev) => [
-          ...prev,
-          { id: nextMessageId(), role: 'assistant' as const, content: '抱歉，连接服务器时出错，请稍后再试。' }
-        ]);
-      },
-      () => {
-        setLoading(false);
-      },
-      activeFilters
-    );
   };
 
   return (
-    <div style={{
+    <div style={{ flex: 1, display: 'flex', height: 'calc(100vh - 128px)' }}>
-      flex: 1,
+      {/* ── Left: chat panel ─────────────────────────────────── */}
-      display: 'flex',
-      height: 'calc(100vh - 128px)',
-    }}>
       <div style={{
         flex: '0 0 60%',
         display: 'flex',
         flexDirection: 'column',
         borderRight: `1px solid ${theme.border}`,
       }}>
+        {/* Message list */}
         <div style={{
           flex: 1,
           overflowY: 'auto',
@@ -219,20 +191,11 @@ export const RagChatPage: React.FC = () => {
           gap: 20,
         }}>
           {messages.length === 0 ? (
-            <div style={{
+            <div style={{ textAlign: 'center', padding: 60, color: theme.text3 }}>
-              textAlign: 'center',
-              padding: 60,
-              color: theme.text3,
-            }}>
               <div style={{
-                width: 72,
+                width: 72, height: 72, borderRadius: 16,
-                height: 72,
+                background: theme.bgCard, display: 'flex', alignItems: 'center',
-                borderRadius: 16,
+                justifyContent: 'center', margin: '0 auto 20px',
-                background: theme.bgCard,
-                display: 'flex',
-                alignItems: 'center',
-                justifyContent: 'center',
-                margin: '0 auto 20px',
                 border: `1px solid ${theme.border}`,
               }}>
                 <svg width="28" height="28" viewBox="0 0 24 24" fill="none">
@@ -245,20 +208,14 @@ export const RagChatPage: React.FC = () => {
           ) : (
             messages.map(msg => (
               <div key={msg.id} style={{
-                display: 'flex',
+                display: 'flex', gap: 12,
-                gap: 12,
                 flexDirection: msg.role === 'user' ? 'row-reverse' : 'row',
               }}>
                 {msg.role === 'assistant' && (
                   <div style={{
-                    width: 32,
+                    width: 32, height: 32, borderRadius: 8,
-                    height: 32,
+                    background: theme.gradientAccent, display: 'flex',
-                    borderRadius: 8,
+                    alignItems: 'center', justifyContent: 'center', flexShrink: 0,
-                    background: theme.gradientAccent,
-                    display: 'flex',
-                    alignItems: 'center',
-                    justifyContent: 'center',
-                    flexShrink: 0,
                   }}>
                     <svg width="16" height="16" viewBox="0 0 24 24" fill="none">
                       <circle cx="12" cy="12" r="6" fill="#fff"/>
@@ -271,16 +228,16 @@ export const RagChatPage: React.FC = () => {
                   background: msg.role === 'user' ? theme.gradientAccent : theme.bgCard,
                   borderRadius: 12,
                   color: msg.role === 'user' ? '#fff' : theme.text,
-                  fontSize: 14,
+                  fontSize: 14, lineHeight: 1.6, whiteSpace: 'pre-wrap',
-                  lineHeight: 1.6,
-                  whiteSpace: 'pre-wrap',
                   border: msg.role === 'assistant' ? `1px solid ${theme.border}` : 'none',
                 }}>
                   {msg.role === 'assistant' ? (
                     <CitedAnswer
                       text={msg.content}
-                      sources={retrievals}
+                      sources={msg.sources ?? retrievals}
                       onCiteClick={(idx) => {
+                        const msgSources = msg.sources ?? retrievals;
+                        setRetrievals(msgSources);
                         setHighlightedSourceIdx(idx);
                         const el = document.getElementById(`source-${idx}`);
                         if (el) el.scrollIntoView({ behavior: 'smooth', block: 'center' });
@@ -289,12 +246,9 @@ export const RagChatPage: React.FC = () => {
                   ) : msg.content}
                   {msg.role === 'assistant' && msg.retrievalIds && msg.retrievalIds.length > 0 && (
                     <div style={{
-                      marginTop: 10,
+                      marginTop: 10, paddingTop: 10,
-                      paddingTop: 10,
                       borderTop: `1px solid ${theme.border}`,
-                      display: 'flex',
+                      display: 'flex', alignItems: 'center', gap: 6,
-                      alignItems: 'center',
-                      gap: 6,
                     }}>
                       <svg width="12" height="12" viewBox="0 0 24 24" fill="none">
                         <path d="M14 2H6C5 2 4 3 4 4V20C4 21 5 22 6 22H18C19 22 20 21 20 20V8L14 2Z" stroke={theme.accent} strokeWidth="1.5"/>
@@ -311,150 +265,115 @@ export const RagChatPage: React.FC = () => {
           {loading && (
             <div style={{ display: 'flex', gap: 12 }}>
               <div style={{
-                width: 32,
+                width: 32, height: 32, borderRadius: 8,
-                height: 32,
+                background: theme.gradientAccent, display: 'flex',
-                borderRadius: 8,
+                alignItems: 'center', justifyContent: 'center',
-                background: theme.gradientAccent,
-                display: 'flex',
-                alignItems: 'center',
-                justifyContent: 'center',
               }}>
                 <svg width="16" height="16" viewBox="0 0 24 24" fill="none">
                   <circle cx="12" cy="12" r="6" fill="#fff"/>
                 </svg>
               </div>
               <div style={{
-                padding: '14px 18px',
+                padding: '14px 18px', background: theme.bgCard,
-                background: theme.bgCard,
+                borderRadius: 12, border: `1px solid ${theme.border}`,
-                borderRadius: 12,
+                display: 'flex', alignItems: 'center', gap: 8,
-                border: `1px solid ${theme.border}`,
-                display: 'flex',
-                alignItems: 'center',
-                gap: 8,
               }}>
                 <div style={{
-                  width: 6,
+                  width: 6, height: 6, borderRadius: '50%',
-                  height: 6,
+                  background: theme.accent, animation: 'pulse 1s infinite',
-                  borderRadius: '50%',
-                  background: theme.accent,
-                  animation: 'pulse 1s infinite',
                 }} />
                 <span style={{ fontSize: 13, color: theme.text2 }}>检索中...</span>
               </div>
             </div>
           )}
+          {/* Scroll anchor */}
+          <div ref={messagesEndRef} />
         </div>
 
-        <div style={{
+        {/* Input area */}
-          padding: '16px 32px 20px',
+        <div style={{ padding: '16px 32px 20px', background: theme.bg, borderTop: `1px solid ${theme.border}` }}>
-          background: theme.bg,
+          {/* Filter row */}
-          borderTop: `1px solid ${theme.border}`,
+          <div style={{ display: 'flex', gap: 8, marginBottom: 10, alignItems: 'center' }}>
-        }}>
-          <div style={{
-            display: 'flex',
-            gap: 8,
-            marginBottom: 10,
-            alignItems: 'center',
-          }}>
             <span className="mono" style={{ fontSize: 11, color: theme.text3, whiteSpace: 'nowrap' }}>法规类型</span>
             <input
               value={filterRegulationType}
-              onChange={(e) => setFilterRegulationType(e.target.value)}
+              onChange={e => setFilterRegulationType(e.target.value)}
               placeholder="如: GB / UN-ECE / IATF（留空不过滤）"
               style={{
-                flex: 1,
+                flex: 1, maxWidth: 280, padding: '5px 10px', fontSize: 12,
-                maxWidth: 280,
+                background: theme.bgHover, border: `1px solid ${theme.border}`,
-                padding: '5px 10px',
+                borderRadius: 6, color: theme.text, outline: 'none',
-                fontSize: 12,
-                background: theme.bgHover,
-                border: `1px solid ${theme.border}`,
-                borderRadius: 6,
-                color: theme.text,
-                outline: 'none',
               }}
             />
           </div>
 
-          <div style={{
+          {/* Quick questions */}
-            display: 'flex',
+          <div style={{ display: 'flex', gap: 8, marginBottom: 12, flexWrap: 'wrap' }}>
-            gap: 8,
-            marginBottom: 12,
-            flexWrap: 'wrap',
-          }}>
             {quickQuestions.map(q => (
               <button
                 key={q}
                 onClick={() => sendMessage(q)}
+                disabled={loading}
                 style={{
-                  padding: '6px 14px',
+                  padding: '6px 14px', fontSize: 12, background: theme.bgCard,
-                  fontSize: 12,
+                  border: `1px solid ${theme.border}`, borderRadius: 6,
-                  background: theme.bgCard,
+                  color: theme.text2, cursor: loading ? 'not-allowed' : 'pointer',
-                  border: `1px solid ${theme.border}`,
-                  borderRadius: 6,
-                  color: theme.text2,
-                  cursor: 'pointer',
                 }}
               >{q}</button>
             ))}
           </div>
 
+          {/* Send row */}
           <div style={{ display: 'flex', gap: 10 }}>
             <input
               value={input}
-              onChange={(e) => setInput(e.target.value)}
+              onChange={e => setInput(e.target.value)}
-              onKeyDown={(e) => e.key === 'Enter' && sendMessage(input)}
+              onKeyDown={e => e.key === 'Enter' && !e.shiftKey && sendMessage(input)}
               placeholder="输入法规问题..."
               style={{
-                flex: 1,
+                flex: 1, padding: 12, fontSize: 14,
-                padding: 12,
+                background: theme.bgCard, border: `1px solid ${theme.border}`,
-                fontSize: 14,
+                borderRadius: 8, color: theme.text, outline: 'none',
-                background: theme.bgCard,
-                border: `1px solid ${theme.border}`,
-                borderRadius: 8,
-                color: theme.text,
-                outline: 'none',
               }}
             />
             <button
               onClick={() => sendMessage(input)}
               disabled={loading || !input.trim()}
               style={{
-                padding: '12px 24px',
+                padding: '12px 24px', fontSize: 14, fontWeight: 600,
-                fontSize: 14,
-                fontWeight: 600,
                 background: loading || !input.trim() ? theme.bgHover : theme.gradientAccent,
                 color: loading || !input.trim() ? theme.text3 : '#fff',
-                border: 'none',
+                border: 'none', borderRadius: 8,
-                borderRadius: 8,
                 cursor: loading || !input.trim() ? 'not-allowed' : 'pointer',
               }}
             >发送</button>
-            {messages.length > 0 && (
+            {loading && (
+              <button
+                onClick={() => { abortRef.current?.abort(); setLoading(false); }}
+                style={{
+                  padding: '12px 16px', fontSize: 13, background: theme.bgCard,
+                  border: `1px solid ${theme.border}`, borderRadius: 8,
+                  color: theme.text2, cursor: 'pointer',
+                }}
+              >停止</button>
+            )}
+            {!loading && messages.length > 0 && (
               <button
                 onClick={() => setShowClearConfirm(true)}
                 style={{
-                  padding: '12px 16px',
+                  padding: '12px 16px', fontSize: 13, background: theme.bgCard,
-                  fontSize: 13,
+                  border: `1px solid ${theme.border}`, borderRadius: 8,
-                  background: theme.bgCard,
+                  color: theme.text2, cursor: 'pointer',
-                  border: `1px solid ${theme.border}`,
-                  borderRadius: 8,
-                  color: theme.text2,
-                  cursor: 'pointer',
                 }}
               >清空</button>
             )}
-            {messages.filter(m => m.role === 'assistant').length > 0 && (
+            {!loading && messages.filter(m => m.role === 'assistant').length > 0 && (
               <button
                 onClick={regenerateLastAnswer}
-                disabled={loading}
                 style={{
-                  padding: '12px 16px',
+                  padding: '12px 16px', fontSize: 13, background: theme.bgCard,
-                  fontSize: 13,
+                  border: `1px solid ${theme.border}`, borderRadius: 8,
-                  background: theme.bgCard,
+                  color: theme.text2, cursor: 'pointer',
-                  border: `1px solid ${theme.border}`,
-                  borderRadius: 8,
-                  color: theme.text2,
-                  cursor: loading ? 'not-allowed' : 'pointer',
                 }}
               >重生成</button>
             )}
@@ -462,27 +381,16 @@ export const RagChatPage: React.FC = () => {
         </div>
       </div>
 
-      <div style={{
+      {/* ── Right: retrieved sources panel ───────────────────── */}
-        flex: '0 0 40%',
+      <div style={{ flex: '0 0 40%', display: 'flex', flexDirection: 'column', background: theme.bgCard }}>
-        display: 'flex',
-        flexDirection: 'column',
-        background: theme.bgCard,
-      }}>
         <div style={{
-          padding: '20px 24px',
+          padding: '20px 24px', borderBottom: `1px solid ${theme.border}`,
-          borderBottom: `1px solid ${theme.border}`,
+          display: 'flex', alignItems: 'center', gap: 10,
-          display: 'flex',
-          alignItems: 'center',
-          gap: 10,
         }}>
           <div style={{
-            width: 28,
+            width: 28, height: 28, borderRadius: 6,
-            height: 28,
+            background: theme.gradientAccent, display: 'flex',
-            borderRadius: 6,
+            alignItems: 'center', justifyContent: 'center',
-            background: theme.gradientAccent,
-            display: 'flex',
-            alignItems: 'center',
-            justifyContent: 'center',
           }}>
             <svg width="14" height="14" viewBox="0 0 24 24" fill="none">
               <path d="M14 2H6C5 2 4 3 4 4V20C4 21 5 22 6 22H18C19 22 20 21 20 20V8L14 2Z" stroke="#fff" strokeWidth="1.5"/>
@@ -493,20 +401,13 @@ export const RagChatPage: React.FC = () => {
           </span>
           {retrievals.length > 0 && (
             <span className="mono" style={{
-              fontSize: 11,
+              fontSize: 11, padding: '4px 10px',
-              padding: '4px 10px',
+              background: theme.bgHover, borderRadius: 4, color: theme.text3,
-              background: theme.bgHover,
-              borderRadius: 4,
-              color: theme.text3,
             }}>{retrievals.length}</span>
           )}
         </div>
 
-        <div style={{
+        <div style={{ flex: 1, overflowY: 'auto', padding: '16px 24px' }}>
-          flex: 1,
-          overflowY: 'auto',
-          padding: '16px 24px',
-        }}>
           {retrievals.length > 0 ? (
             <div style={{ display: 'flex', flexDirection: 'column', gap: 12 }}>
               {retrievals.map((r, i) => (
@@ -515,30 +416,20 @@ export const RagChatPage: React.FC = () => {
                   id={`source-${i + 1}`}
                   onClick={() => setSelectedRetrieval(r)}
                   style={{
-                    padding: 16,
+                    padding: 16, background: highlightedSourceIdx === i + 1 ? theme.bgElevated : theme.bgHover,
-                    background: highlightedSourceIdx === i + 1 ? theme.bgElevated : theme.bgHover,
+                    borderRadius: 10, border: `1px solid ${highlightedSourceIdx === i + 1 ? theme.accent : theme.border}`,
-                    borderRadius: 10,
+                    cursor: 'pointer', position: 'relative',
-                    border: `1px solid ${highlightedSourceIdx === i + 1 ? theme.accent : theme.border}`,
-                    cursor: 'pointer',
-                    position: 'relative',
                     transition: 'border-color 0.2s, background 0.2s',
                   }}
                 >
                   <div style={{
-                    position: 'absolute',
+                    position: 'absolute', left: 0, top: 16, bottom: 16,
-                    left: 0,
+                    width: 3, background: theme.gradientAccent, borderRadius: 2,
-                    top: 16,
-                    bottom: 16,
-                    width: 3,
-                    background: theme.gradientAccent,
-                    borderRadius: 2,
                   }} />
                   <div style={{ paddingLeft: 8 }}>
                     <div style={{
-                      display: 'flex',
+                      display: 'flex', alignItems: 'center',
-                      alignItems: 'center',
+                      justifyContent: 'space-between', marginBottom: 8,
-                      justifyContent: 'space-between',
-                      marginBottom: 8,
                     }}>
                       <span className="mono" style={{ fontSize: 11, fontWeight: 700, color: theme.accent }}>#{i + 1}</span>
                       <div style={{ display: 'flex', alignItems: 'center', gap: 10 }}>
@@ -547,17 +438,13 @@ export const RagChatPage: React.FC = () => {
                             href={r.downloadUrl}
                             target="_blank"
                             rel="noreferrer"
-                            onClick={(event) => event.stopPropagation()}
+                            onClick={e => e.stopPropagation()}
                             style={{ fontSize: 11, color: theme.accent, textDecoration: 'none' }}
-                          >
+                          >下载文档</a>
-                            下载文档
-                          </a>
                         )}
-                        <span className="mono" style={{
+                        <span className="mono" style={{ fontSize: 11, fontWeight: 600, color: theme.accent }}>
-                          fontSize: 11,
+                          {(r.score * 100).toFixed(0)}%
-                          fontWeight: 600,
+                        </span>
-                          color: theme.accent,
-                        }}>{(r.score * 100).toFixed(0)}%</span>
                       </div>
                     </div>
                     <div style={{ fontSize: 13, fontWeight: 500, marginBottom: 4, color: theme.text }}>{r.file}</div>
@@ -565,32 +452,20 @@ export const RagChatPage: React.FC = () => {
                       {r.clause}{r.docId ? ` · ${r.docId}` : ''}
                     </div>
                     <div style={{
-                      fontSize: 12,
+                      fontSize: 12, color: theme.text2, lineHeight: 1.5,
-                      color: theme.text2,
+                      display: '-webkit-box', WebkitLineClamp: 3,
-                      lineHeight: 1.5,
+                      WebkitBoxOrient: 'vertical', overflow: 'hidden',
-                      overflow: 'hidden',
-                      textOverflow: 'ellipsis',
-                      whiteSpace: 'nowrap',
                     }}>{r.content}</div>
                   </div>
                 </div>
               ))}
             </div>
           ) : (
-            <div style={{
+            <div style={{ textAlign: 'center', padding: 40, color: theme.text3 }}>
-              textAlign: 'center',
-              padding: 40,
-              color: theme.text3,
-            }}>
               <div style={{
-                width: 48,
+                width: 48, height: 48, borderRadius: 10,
-                height: 48,
+                background: theme.bgHover, display: 'flex', alignItems: 'center',
-                borderRadius: 10,
+                justifyContent: 'center', margin: '0 auto 16px',
-                background: theme.bgHover,
-                display: 'flex',
-                alignItems: 'center',
-                justifyContent: 'center',
-                margin: '0 auto 16px',
               }}>
                 <svg width="20" height="20" viewBox="0 0 24 24" fill="none">
                   <path d="M14 2H6C5 2 4 3 4 4V20C4 21 5 22 6 22H18C19 22 20 21 20 20V8L14 2Z" stroke={theme.text3} strokeWidth="1.5"/>
@@ -602,52 +477,33 @@ export const RagChatPage: React.FC = () => {
         </div>
       </div>
 
+      {/* ── Clear confirm modal ───────────────────────────────── */}
       {showClearConfirm && (
         <div style={{
-          position: 'fixed',
+          position: 'fixed', top: 0, left: 0, right: 0, bottom: 0,
-          top: 0,
+          background: 'rgba(0,0,0,0.6)', display: 'flex',
-          left: 0,
+          alignItems: 'center', justifyContent: 'center', zIndex: 1000,
-          right: 0,
-          bottom: 0,
-          background: 'rgba(0,0,0,0.6)',
-          display: 'flex',
-          alignItems: 'center',
-          justifyContent: 'center',
-          zIndex: 1000,
         }}>
           <div style={{
-            padding: 24,
+            padding: 24, background: theme.bgCard, borderRadius: 16,
-            background: theme.bgCard,
+            maxWidth: 400, border: `1px solid ${theme.border}`,
-            borderRadius: 16,
-            maxWidth: 400,
-            border: `1px solid ${theme.border}`,
           }}>
             <div style={{ fontSize: 15, fontWeight: 600, marginBottom: 12, color: theme.text }}>确定清空对话？</div>
-            <div style={{ fontSize: 13, color: theme.text2, marginBottom: 20 }}>此操作不可恢复</div>
+            <div style={{ fontSize: 13, color: theme.text2, marginBottom: 20 }}>此操作不可恢复，会话历史将被重置</div>
             <div style={{ display: 'flex', gap: 10, justifyContent: 'flex-end' }}>
               <button
                 onClick={() => setShowClearConfirm(false)}
                 style={{
-                  padding: '10px 18px',
+                  padding: '10px 18px', fontSize: 13, background: theme.bgHover,
-                  fontSize: 13,
+                  border: 'none', borderRadius: 8, color: theme.text2, cursor: 'pointer',
-                  background: theme.bgHover,
-                  border: 'none',
-                  borderRadius: 8,
-                  color: theme.text2,
-                  cursor: 'pointer',
                 }}
               >取消</button>
               <button
                 onClick={clearMessages}
                 style={{
-                  padding: '10px 18px',
+                  padding: '10px 18px', fontSize: 13, fontWeight: 600,
-                  fontSize: 13,
+                  background: theme.accent, border: 'none', borderRadius: 8,
-                  fontWeight: 600,
+                  color: '#fff', cursor: 'pointer',
-                  background: theme.accent,
-                  border: 'none',
-                  borderRadius: 8,
-                  color: '#fff',
-                  cursor: 'pointer',
                 }}
               >确认</button>
             </div>
@@ -655,47 +511,31 @@ export const RagChatPage: React.FC = () => {
         </div>
       )}
 
+      {/* ── Source detail modal ───────────────────────────────── */}
       {selectedRetrieval && (
         <div
           onClick={() => setSelectedRetrieval(null)}
           style={{
-            position: 'fixed',
+            position: 'fixed', top: 0, left: 0, right: 0, bottom: 0,
-            top: 0,
+            background: 'rgba(0,0,0,0.6)', display: 'flex',
-            left: 0,
+            alignItems: 'center', justifyContent: 'center', zIndex: 1000,
-            right: 0,
-            bottom: 0,
-            background: 'rgba(0,0,0,0.6)',
-            display: 'flex',
-            alignItems: 'center',
-            justifyContent: 'center',
-            zIndex: 1000,
           }}
         >
           <div
-            onClick={(e) => e.stopPropagation()}
+            onClick={e => e.stopPropagation()}
             style={{
-              width: 520,
+              width: 520, maxWidth: '90%', maxHeight: '80%',
-              maxWidth: '90%',
+              overflowY: 'auto', padding: 24, background: theme.bgCard,
-              maxHeight: '80%',
+              borderRadius: 16, border: `1px solid ${theme.accent}`,
-              padding: 24,
-              background: theme.bgCard,
-              borderRadius: 16,
-              border: `1px solid ${theme.accent}`,
               boxShadow: '0 8px 32px rgba(0,0,0,0.3)',
             }}
           >
             <div style={{
-              display: 'flex',
+              display: 'flex', alignItems: 'center',
-              alignItems: 'center',
+              justifyContent: 'space-between', marginBottom: 16,
-              justifyContent: 'space-between',
-              marginBottom: 16,
             }}>
               <div style={{ display: 'flex', alignItems: 'center', gap: 10, flexWrap: 'wrap' }}>
-                <div style={{
+                <div style={{ padding: '4px 10px', background: theme.gradientAccent, borderRadius: 6 }}>
-                  padding: '4px 10px',
-                  background: theme.gradientAccent,
-                  borderRadius: 6,
-                }}>
                   <span className="mono" style={{ fontSize: 11, fontWeight: 600, color: '#fff' }}>
                     {(selectedRetrieval.score * 100).toFixed(0)}%
                   </span>
@@ -707,23 +547,15 @@ export const RagChatPage: React.FC = () => {
                     target="_blank"
                     rel="noreferrer"
                     style={{ fontSize: 12, color: theme.accent, textDecoration: 'none' }}
-                  >
+                  >下载关联文档</a>
-                    下载关联文档
-                  </a>
                 )}
               </div>
               <button
                 onClick={() => setSelectedRetrieval(null)}
                 style={{
-                  width: 28,
+                  width: 28, height: 28, background: theme.bgHover,
-                  height: 28,
+                  border: 'none', borderRadius: 6, cursor: 'pointer',
-                  background: theme.bgHover,
+                  display: 'flex', alignItems: 'center', justifyContent: 'center',
-                  border: 'none',
-                  borderRadius: 6,
-                  cursor: 'pointer',
-                  display: 'flex',
-                  alignItems: 'center',
-                  justifyContent: 'center',
                 }}
               >
                 <svg width="14" height="14" viewBox="0 0 24 24" fill="none">
@@ -731,23 +563,15 @@ export const RagChatPage: React.FC = () => {
                 </svg>
               </button>
             </div>
-            <div style={{
+            <div style={{ padding: '10px 14px', background: theme.bgHover, borderRadius: 8, marginBottom: 16 }}>
-              padding: '10px 14px',
-              background: theme.bgHover,
-              borderRadius: 8,
-              marginBottom: 16,
-            }}>
               <span className="mono" style={{ fontSize: 12, color: theme.accent }}>{selectedRetrieval.clause}</span>
               {selectedRetrieval.docId && (
                 <span className="mono" style={{ fontSize: 11, color: theme.text3, marginLeft: 8 }}>{selectedRetrieval.docId}</span>
               )}
             </div>
-            <div style={{
+            <div style={{ fontSize: 14, lineHeight: 1.7, color: theme.text2, whiteSpace: 'pre-wrap' }}>
-              fontSize: 14,
+              {selectedRetrieval.content}
-              lineHeight: 1.7,
+            </div>
-              color: theme.text2,
-              whiteSpace: 'pre-wrap',
-            }}>{selectedRetrieval.content}</div>
           </div>
         </div>
       )}

frontend/src/types/doc.ts

@@ -25,6 +25,7 @@ export interface ChatMessage {
   role: 'user' | 'assistant';
   content: string;
   retrievalIds?: number[];
+  sources?: RetrievalData[];
 }
 
 export interface RetrievalData {