fix(undo): 修复撤销按钮状态不刷新及空指针防护

- 将 refresh_undo_redo_buttons 提升为公共函数（声明在 callbacks_internal.h，实现在 callbacks.c）
- 在所有 push_record 的操作回调末尾调用 refresh_undo_redo_buttons，确保按钮状态实时更新
- 修复 redo() 中 OP_CLEAN/OP_IMPORT 的 new_paths 空指针风险
- 移除 undo_redo.c 中废弃的 apply_record 函数

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

include/controller/callbacks_internal.h

@@ -20,4 +20,7 @@ StringList *get_current_raw_data(Ihandle *dlg);
 // 获取当前活动的列表 UI 控件
 Ihandle *get_current_list(Ihandle *dlg);
 
+// 刷新撤销/重做按钮的启用状态
+void refresh_undo_redo_buttons(Ihandle *dlg);
+
 #endif // CALLBACKS_INTERNAL_H

src/controller/callbacks.c

@@ -1,6 +1,7 @@
 #include "controller/callbacks.h"
 #include "controller/callbacks_internal.h"
 #include "core/app_context.h"
+#include "core/undo_redo.h"
 #include "utils/ui_constants.h"
 #include <iup.h>
 
@@ -45,3 +46,19 @@ Ihandle *get_current_list(Ihandle *dlg)
         return IupGetDialogChild(dlg, CTRL_LIST_USER);
     return IupGetDialogChild(dlg, CTRL_LIST_SYS);
 }
+
+// 刷新撤销/重做按钮的启用状态
+void refresh_undo_redo_buttons(Ihandle *dlg)
+{
+    AppContext *ctx = get_app_context_from_dlg(dlg);
+    if (!ctx || !ctx->undo_redo_mgr)
+        return;
+
+    Ihandle *btn_undo = IupGetDialogChild(dlg, CTRL_BTN_UNDO);
+    Ihandle *btn_redo = IupGetDialogChild(dlg, CTRL_BTN_REDO);
+
+    if (btn_undo)
+        IupSetAttribute(btn_undo, "ACTIVE", can_undo(ctx->undo_redo_mgr) ? "YES" : "NO");
+    if (btn_redo)
+        IupSetAttribute(btn_redo, "ACTIVE", can_redo(ctx->undo_redo_mgr) ? "YES" : "NO");
+}

src/controller/callbacks_basic.c

@@ -76,6 +76,8 @@ int btn_new_cb(Ihandle *self)
 
             int count = IupGetInt(current_list, "COUNT");
             IupSetInt(current_list, "VALUE", count);
+
+            refresh_undo_redo_buttons(dlg);
         }
     }
     return IUP_DEFAULT;
@@ -114,6 +116,8 @@ int btn_edit_cb(Ihandle *self)
 
             sync_string_list_to_ui(current_list, raw_data);
             IupSetInt(current_list, "VALUE", selected);
+
+            refresh_undo_redo_buttons(dlg);
         }
     }
     return IUP_DEFAULT;
@@ -168,6 +172,8 @@ int btn_browse_cb(Ihandle *self)
 
             int count = IupGetInt(current_list, "COUNT");
             IupSetInt(current_list, "VALUE", count);
+
+            refresh_undo_redo_buttons(dlg);
         }
     }
     IupDestroy(filedlg);
@@ -208,5 +214,6 @@ int btn_del_cb(Ihandle *self)
     if (lbl_status)
         IupSetAttribute(lbl_status, "TITLE", lua_config_get_string("status", "deleted"));
 
+    refresh_undo_redo_buttons(dlg);
     return IUP_DEFAULT;
 }

src/controller/callbacks_nav.c

@@ -71,6 +71,7 @@ int btn_up_cb(Ihandle *self)
     sync_string_list_to_ui(current_list, raw_data);
     IupSetInt(current_list, "VALUE", selected - 1);
 
+    refresh_undo_redo_buttons(dlg);
     return IUP_DEFAULT;
 }
 
@@ -104,6 +105,7 @@ int btn_down_cb(Ihandle *self)
     sync_string_list_to_ui(current_list, raw_data);
     IupSetInt(current_list, "VALUE", selected + 1);
 
+    refresh_undo_redo_buttons(dlg);
     return IUP_DEFAULT;
 }
 
@@ -142,25 +144,11 @@ int btn_clean_cb(Ihandle *self)
     char msg[128];
     snprintf(msg, sizeof(msg), _("Cleanup completed! Removed %d invalid or duplicate paths."), removed);
     IupMessage(_("Info"), msg);
+
+    refresh_undo_redo_buttons(dlg);
     return IUP_DEFAULT;
 }
 
-// 刷新撤销/重做按钮的启用状态
-static void refresh_undo_redo_buttons(Ihandle *dlg)
-{
-    AppContext *ctx = get_app_context_from_dlg(dlg);
-    if (!ctx || !ctx->undo_redo_mgr)
-        return;
-
-    Ihandle *btn_undo = IupGetDialogChild(dlg, CTRL_BTN_UNDO);
-    Ihandle *btn_redo = IupGetDialogChild(dlg, CTRL_BTN_REDO);
-
-    if (btn_undo)
-        IupSetAttribute(btn_undo, "ACTIVE", can_undo(ctx->undo_redo_mgr) ? "YES" : "NO");
-    if (btn_redo)
-        IupSetAttribute(btn_redo, "ACTIVE", can_redo(ctx->undo_redo_mgr) ? "YES" : "NO");
-}
-
 int btn_undo_cb(Ihandle *self)
 {
     Ihandle *dlg = IupGetDialog(self);

src/core/undo_redo.c

@@ -128,14 +128,6 @@ int push_undo_record(UndoRedoManager *mgr, const OpRecord *record)
     return 0;
 }
 
-static void apply_record(UndoRedoManager *mgr, int record_index, int is_undo)
-{
-    (void)mgr;
-    (void)record_index;
-    (void)is_undo;
-    // 此函数已废弃，撤销/重做逻辑在 undo() 和 redo() 中直接实现
-}
-
 int undo(UndoRedoManager *mgr, StringList *sys_paths, StringList *user_paths)
 {
     if (!mgr || !can_undo(mgr))
@@ -268,10 +260,13 @@ int redo(UndoRedoManager *mgr, StringList *sys_paths, StringList *user_paths)
     case OP_IMPORT:
         // 重做清理/导入：应用新列表
         clear_string_list(target);
-        for (int i = 0; i < rec->count; i++)
+        if (rec->new_paths)
         {
-            if (rec->new_paths[i])
+            for (int i = 0; i < rec->count; i++)
-                add_string_list(target, rec->new_paths[i]);
+            {
+                if (rec->new_paths[i])
+                    add_string_list(target, rec->new_paths[i]);
+            }
         }
         break;