From 7535f77eaab9a4271257f128871078db396b3cc8 Mon Sep 17 00:00:00 2001
From: digua <i@digua.me>
Date: Mon, 11 May 2026 19:56:14 +0800
Subject: [PATCH] feat(node-runtime): add DatabaseManager for session DB
 lifecycle

Phase 1.7: add DatabaseManager to @openchatlab/node-runtime that handles
opening, caching, listing, and closing chat session databases using the
DatabaseAdapter and PathProvider interfaces from core.
---
 packages/node-runtime/src/database-manager.ts | 83 +++++++++++++++++++
 packages/node-runtime/src/index.ts            |  3 +-
 2 files changed, 85 insertions(+), 1 deletion(-)
 create mode 100644 packages/node-runtime/src/database-manager.ts

diff --git a/packages/node-runtime/src/database-manager.ts b/packages/node-runtime/src/database-manager.ts
new file mode 100644
index 00000000..3afeefb6
--- /dev/null
+++ b/packages/node-runtime/src/database-manager.ts
@@ -0,0 +1,83 @@
+/**
+ * 数据库连接管理器
+ *
+ * 管理 ChatLab 会话数据库的打开、缓存与关闭。
+ * 等效于 electron/main/worker/core/dbCore.ts 中的 dbCache 机制，
+ * 但基于 DatabaseAdapter 接口而非直接使用 better-sqlite3。
+ */
+
+import * as fs from 'fs'
+import * as path from 'path'
+import type { DatabaseAdapter, PathProvider } from '@openchatlab/core'
+import { isChatSessionDb } from '@openchatlab/core'
+import { openBetterSqliteDatabase } from './better-sqlite3-adapter'
+
+export class DatabaseManager {
+  private cache = new Map<string, DatabaseAdapter>()
+
+  constructor(private pathProvider: PathProvider) {}
+
+  /**
+   * 打开指定会话的数据库（带缓存）
+   */
+  open(sessionId: string, options?: { readonly?: boolean }): DatabaseAdapter | null {
+    if (this.cache.has(sessionId)) {
+      return this.cache.get(sessionId)!
+    }
+
+    const dbPath = this.getDbPath(sessionId)
+    if (!fs.existsSync(dbPath)) return null
+
+    const adapter = openBetterSqliteDatabase(dbPath, {
+      readonly: options?.readonly ?? true,
+    })
+    this.cache.set(sessionId, adapter)
+    return adapter
+  }
+
+  /**
+   * 关闭指定会话的数据库连接
+   */
+  close(sessionId: string): void {
+    const adapter = this.cache.get(sessionId)
+    if (adapter) {
+      adapter.close()
+      this.cache.delete(sessionId)
+    }
+  }
+
+  /**
+   * 关闭所有数据库连接
+   */
+  closeAll(): void {
+    for (const [id, adapter] of this.cache) {
+      adapter.close()
+      this.cache.delete(id)
+    }
+  }
+
+  /**
+   * 列举数据库目录下的所有聊天会话 ID
+   */
+  listSessionIds(): string[] {
+    const dbDir = this.pathProvider.getDatabaseDir()
+    if (!fs.existsSync(dbDir)) return []
+
+    return fs
+      .readdirSync(dbDir)
+      .filter((f) => f.endsWith('.db'))
+      .map((f) => f.replace('.db', ''))
+      .filter((id) => {
+        const db = this.open(id)
+        if (!db) return false
+        return isChatSessionDb(db)
+      })
+  }
+
+  /**
+   * 获取数据库文件路径
+   */
+  getDbPath(sessionId: string): string {
+    return path.join(this.pathProvider.getDatabaseDir(), `${sessionId}.db`)
+  }
+}
diff --git a/packages/node-runtime/src/index.ts b/packages/node-runtime/src/index.ts
index f6c239e0..d3d162ca 100644
--- a/packages/node-runtime/src/index.ts
+++ b/packages/node-runtime/src/index.ts
@@ -2,8 +2,9 @@
  * @openchatlab/node-runtime
  *
  * Node.js 运行时适配器，提供 better-sqlite3 数据库适配器、
- * 路径管理等平台特定实现。
+ * 路径管理、数据库连接管理等平台特定实现。
  */
 
 export { BetterSqliteAdapter, openBetterSqliteDatabase } from './better-sqlite3-adapter'
 export { NodePathProvider } from './node-path-provider'
+export { DatabaseManager } from './database-manager'