fix(mongo): complete agent fallback for all connection paths

- Fix connect_db and test_connection to also fallback to agent when
  native driver fails with wire version error
- Route MongoDB agent through mongo_ops in schema.rs list_databases
- Update MongoDB legacy hint text to mention Driver Manager

crates/dbx-core/src/schema.rs

@@ -3,6 +3,7 @@ use std::sync::Arc;
 
 use crate::connection::{AppState, MysqlMode, PoolKind};
 use crate::db;
+use crate::models::connection::DatabaseType;
 
 pub fn duckdb_query_tables(con: &duckdb::Connection) -> Result<Vec<db::TableInfo>, String> {
     let mut stmt = con.prepare(
@@ -136,6 +137,13 @@ pub async fn list_databases_core(state: &AppState, connection_id: &str) -> Resul
             return db::sqlserver::list_databases(&mut client).await;
         }
         if let Some(client) = extract_agent(&connections, connection_id) {
+            let is_mongo =
+                state.configs.read().await.get(connection_id).is_some_and(|c| c.db_type == DatabaseType::MongoDb);
+            if is_mongo {
+                drop(connections);
+                let dbs = crate::mongo_ops::mongo_list_databases_core(state, connection_id).await?;
+                return Ok(dbs.into_iter().map(|name| db::DatabaseInfo { name }).collect());
+            }
             drop(connections);
             let mut client = client.lock().await;
             return client.call("list_databases", serde_json::json!({})).await;

src-tauri/src/commands/connection.rs

@@ -81,12 +81,29 @@ pub async fn test_connection(state: State<'_, Arc<AppState>>, config: Connection
             DatabaseType::DuckDb => duckdb::Connection::open(&expand_tilde(&config.host))
                 .map(|_| "Connection successful".to_string())
                 .map_err(|e| e.to_string()),
-            DatabaseType::MongoDb => match db::mongo_driver::connect(&url).await {
-                Ok(client) => {
-                    db::mongo_driver::test_connection(&client).await.map(|_| "Connection successful".to_string())
+            DatabaseType::MongoDb => {
+                let native_err = match db::mongo_driver::connect(&url).await {
+                    Ok(client) => match db::mongo_driver::test_connection(&client).await {
+                        Ok(()) => return Ok("Connection successful".to_string()),
+                        Err(e) => e,
+                    },
+                    Err(e) => e,
+                };
+                if native_err.contains("wire version") {
+                    let am = &state.agent_manager;
+                    let mut client = am.spawn(&config.db_type, config.driver_profile.as_deref()).await?;
+                    let params = serde_json::json!({ "connection": {
+                        "host": host, "port": port,
+                        "database": config.effective_database().unwrap_or(""),
+                        "username": config.username, "password": config.password,
+                    }});
+                    client.call::<serde_json::Value>("connect", params).await?;
+                    client.call::<serde_json::Value>("disconnect", serde_json::json!({})).await.ok();
+                    Ok("Connection successful (via legacy driver)".to_string())
+                } else {
+                    Err(native_err)
                 }
-                Err(e) => Err(e.to_string()),
-            },
+            }
             DatabaseType::ClickHouse => {
                 let username = if config.username.is_empty() { None } else { Some(config.username.clone()) };
                 let password = if config.password.is_empty() { None } else { Some(config.password.clone()) };
@@ -170,9 +187,31 @@ pub async fn connect_db(state: State<'_, Arc<AppState>>, config: ConnectionConfi
             PoolKind::DuckDb(std::sync::Arc::new(std::sync::Mutex::new(con)))
         }
         DatabaseType::MongoDb => {
-            let client = db::mongo_driver::connect(&url).await?;
-            db::mongo_driver::test_connection(&client).await?;
-            PoolKind::MongoDb(client)
+            let native_err = match db::mongo_driver::connect(&url).await {
+                Ok(client) => match db::mongo_driver::test_connection(&client).await {
+                    Ok(()) => {
+                        state.configs.write().await.insert(id.clone(), config);
+                        state.connections.write().await.insert(id.clone(), PoolKind::MongoDb(client));
+                        return Ok(id);
+                    }
+                    Err(e) => e,
+                },
+                Err(e) => e,
+            };
+            if native_err.contains("wire version") {
+                log::info!("Native MongoDB driver failed ({native_err}), falling back to agent driver");
+                let mut client =
+                    state.agent_manager.spawn(&db_config.db_type, db_config.driver_profile.as_deref()).await?;
+                let params = serde_json::json!({ "connection": {
+                    "host": host, "port": port,
+                    "database": db_config.effective_database().unwrap_or(""),
+                    "username": db_config.username, "password": db_config.password,
+                }});
+                client.call::<serde_json::Value>("connect", params).await?;
+                PoolKind::Agent(std::sync::Arc::new(tokio::sync::Mutex::new(client)))
+            } else {
+                return Err(native_err);
+            }
         }
         DatabaseType::ClickHouse => {
             let username = if db_config.username.is_empty() { None } else { Some(db_config.username.clone()) };

src/i18n/locales/en.ts

@@ -179,7 +179,7 @@ export default {
     dmCompatHint: "Requires DM8 ODBC driver installed on your system.",
     dmDownload: "Download from Dameng",
     mongoLegacyHint:
-      "For older MongoDB servers, enter authSource=admin&authMechanism=SCRAM-SHA-1 here; add directConnection=true only when needed for direct standalone connections.",
+      "MongoDB below 4.2 requires the MongoDB (Legacy) driver from Driver Manager; connections will switch automatically.",
     compatible: "Compatible",
     mainstream: "Popular",
     color: "Color",

src/i18n/locales/es.ts

@@ -180,7 +180,7 @@ export default {
     dmCompatHint: "Requiere el driver ODBC DM8 instalado en el sistema.",
     dmDownload: "Descargar desde Dameng",
     mongoLegacyHint:
-      "Para servidores MongoDB más antiguos, ingresa authSource=admin&authMechanism=SCRAM-SHA-1 aquí; agrega directConnection=true solo cuando sea necesario para conexiones directas a instancias independientes.",
+      "MongoDB inferior a 4.2 requiere el controlador MongoDB (Legacy) del Gestor de controladores; la conexión cambiará automáticamente.",
     compatible: "Compatible",
     mainstream: "Popular",
     color: "Color",

src/i18n/locales/zh-CN.ts

@@ -176,8 +176,7 @@ export default {
     jdbcPluginHint: "先安装 DBX JDBC 插件，再导入数据库厂商提供的 JDBC 驱动 JAR。",
     dmCompatHint: "需要在系统上安装达梦 DM8 ODBC 驱动程序。",
     dmDownload: "前往达梦官网下载",
-    mongoLegacyHint:
-      "连接旧版 MongoDB 时，可在此填写 authSource=admin&authMechanism=SCRAM-SHA-1；直连单节点时可按需追加 directConnection=true。",
+    mongoLegacyHint: "MongoDB 4.2 以下版本需在驱动管理中安装 MongoDB (Legacy) 驱动，连接时将自动切换。",
     compatible: "兼容",
     mainstream: "主流",
     color: "颜色",