feat: 搜索工具自动携带上下文消息

electron/main/worker/query/messages.ts

@@ -526,6 +526,115 @@ export function getMessageContext(
   return rows.map(sanitizeMessageRow)
 }
 
+/**
+ * 获取搜索结果的上下文消息（会话感知 + 区间合并去重）
+ * 用于 search_messages / deep_search_messages 自动扩展上下文。
+ * 当存在会话索引时，上下文不跨会话边界；否则按 message.id 顺序取前后 N 条。
+ *
+ * @param sessionId 数据库会话 ID
+ * @param messageIds 搜索命中的消息 ID 列表
+ * @param contextBefore 每条命中消息向前取多少条上下文
+ * @param contextAfter 每条命中消息向后取多少条上下文
+ */
+export function getSearchMessageContext(
+  sessionId: string,
+  messageIds: number[],
+  contextBefore: number = 2,
+  contextAfter: number = 2
+): MessageResult[] {
+  ensureAvatarColumn(sessionId)
+  const db = openDatabase(sessionId)
+  if (!db) return []
+  if (messageIds.length === 0) return []
+
+  const contextIds = new Set<number>()
+
+  const hasSessionData =
+    (db.prepare('SELECT 1 FROM message_context LIMIT 1').get() as { 1: number } | undefined) !== undefined
+
+  for (const messageId of messageIds) {
+    contextIds.add(messageId)
+
+    if (hasSessionData) {
+      const sessionRow = db
+        .prepare('SELECT session_id FROM message_context WHERE message_id = ?')
+        .get(messageId) as { session_id: number } | undefined
+
+      if (sessionRow) {
+        if (contextBefore > 0) {
+          const rows = db
+            .prepare(
+              `SELECT mc.message_id as id
+               FROM message_context mc
+               WHERE mc.session_id = ? AND mc.message_id < ?
+               ORDER BY mc.message_id DESC
+               LIMIT ?`
+            )
+            .all(sessionRow.session_id, messageId, contextBefore) as { id: number }[]
+          rows.forEach((r) => contextIds.add(r.id))
+        }
+        if (contextAfter > 0) {
+          const rows = db
+            .prepare(
+              `SELECT mc.message_id as id
+               FROM message_context mc
+               WHERE mc.session_id = ? AND mc.message_id > ?
+               ORDER BY mc.message_id ASC
+               LIMIT ?`
+            )
+            .all(sessionRow.session_id, messageId, contextAfter) as { id: number }[]
+          rows.forEach((r) => contextIds.add(r.id))
+        }
+        continue
+      }
+    }
+
+    // Fallback: no session data or message not indexed — use simple id-based context
+    if (contextBefore > 0) {
+      const rows = db
+        .prepare('SELECT id FROM message WHERE id < ? ORDER BY id DESC LIMIT ?')
+        .all(messageId, contextBefore) as { id: number }[]
+      rows.forEach((r) => contextIds.add(r.id))
+    }
+    if (contextAfter > 0) {
+      const rows = db
+        .prepare('SELECT id FROM message WHERE id > ? ORDER BY id ASC LIMIT ?')
+        .all(messageId, contextAfter) as { id: number }[]
+      rows.forEach((r) => contextIds.add(r.id))
+    }
+  }
+
+  if (contextIds.size === 0) return []
+
+  const idList = Array.from(contextIds)
+  const placeholders = idList.map(() => '?').join(', ')
+
+  const sql = `
+    SELECT
+      msg.id,
+      m.id as senderId,
+      COALESCE(m.group_nickname, m.account_name, m.platform_id) as senderName,
+      m.platform_id as senderPlatformId,
+      m.aliases,
+      m.avatar,
+      msg.content,
+      msg.ts as timestamp,
+      msg.type,
+      msg.reply_to_message_id,
+      reply_msg.content as replyToContent,
+      COALESCE(reply_m.group_nickname, reply_m.account_name, reply_m.platform_id) as replyToSenderName
+    FROM message msg
+    JOIN member m ON msg.sender_id = m.id
+    LEFT JOIN message reply_msg ON msg.reply_to_message_id = reply_msg.platform_message_id
+    LEFT JOIN member reply_m ON reply_msg.sender_id = reply_m.id
+    WHERE msg.id IN (${placeholders})
+    ORDER BY msg.ts ASC, msg.id ASC
+  `
+
+  const rows = db.prepare(sql).all(...idList) as DbMessageRow[]
+  return rows.map(sanitizeMessageRow)
+}
+
 /**
  * 获取指定消息之前的 N 条消息（用于向上无限滚动）
  * @param sessionId 会话 ID