fix: top/bottom edge resize broken — menubar ate events + minimumSize clamped to 1121px

Two independent root causes for '左右能拉，上下不能拉':

1. Event delivery: the top 6px edge band belongs to QMenuBar, which
   actively consumes mouse events (menu hover) — nothing ever propagated
   to QMainWindow, so T/TL/TR (and maximize-restore from top edge) were
   dead on every platform. Install an event filter on menuBar()/statusBar():
   within the edge band it handles hover cursor, press (grabMouse), drag
   and release; outside the band everything passes through (menus open
   normally, native QSizeGrip corner drag preserved).

2. Layout minimum: MonitorPanel's minimumSizeHint (~1015px of stacked
   tables/group boxes) propagated through QTabWidget → central widget →
   QMainWindow, making the window minimum size 898x1121. Any vertical
   shrink was clamped dead. Set explicit per-tab-page minimumSize
   (320x200) + window minimumSize (760x480).

Tests: test_resize.py now drives edges through real event delivery
(childAt → child widget, propagation/filter path) for L/R/T/B/TL/TR/BL,
verifies BR stays on QSizeGrip, maximize-restore via menubar filter,
and minimum-size regression. All 8 suites pass.

test_resize.py

@@ -1,8 +1,11 @@
 """
 窗口边缘拖动测试：
 - _hit_test_edge 返回正确的边
-- mouseMove + mousePress 模拟拖动
+- mouseMove + mousePress 模拟拖动（直接投递到 QMainWindow）
 - 普通模式 + 最大化模式都覆盖
+- 真实事件投递（childAt → 子控件，依赖传播/事件过滤器）：4 边 + 3 角
+- 最大化时真实按压菜单栏顶缘 → 还原
+- 最小尺寸合理性（回归：MinimumSizeHint 曾把窗口最小高度撑到 1121px，上下无法缩小）
 """
 import os
 import sys
@@ -12,7 +15,7 @@ sys.path.insert(0, os.path.dirname(__file__))
 
 from PyQt5.QtCore import Qt, QPoint, QEvent
 from PyQt5.QtGui import QMouseEvent
-from PyQt5.QtWidgets import QApplication
+from PyQt5.QtWidgets import QApplication, QSizeGrip
 
 from ui.main_window import MainWindow
 
@@ -23,6 +26,35 @@ def make_mouse_event(type_, pos, button=Qt.LeftButton):
     return QMouseEvent(type_, pos, glb, button, button, Qt.NoModifier)
 
 
+def deliver(target, type_, local_pos, button=Qt.LeftButton, buttons=Qt.NoButton):
+    """把事件投给 target（模拟 Qt 投给光标下子控件的真实路径）"""
+    ev = QMouseEvent(type_, local_pos, QPoint(local_pos.x(), local_pos.y()),
+                     button, buttons, Qt.NoModifier)
+    QApplication.sendEvent(target, ev)
+    return ev
+
+
+def try_real_drag(w, press_pos, delta, expected_edge):
+    """真实投递：press 到 childAt 命中的控件 → move → release。
+    返回 (命中控件, geo_before, geo_after)"""
+    child = w.childAt(press_pos)
+    target = child if child else w
+    local = target.mapFrom(w, press_pos) if child else press_pos
+    geo0 = w.geometry()
+    deliver(target, QEvent.MouseButtonPress, local,
+            button=Qt.LeftButton, buttons=Qt.LeftButton)
+    assert w._resize_edge == expected_edge, \
+        f"{expected_edge}: press 后 _resize_edge={w._resize_edge!r}（命中 {type(target).__name__}）"
+    moved = QPoint(local.x() + delta[0], local.y() + delta[1])
+    deliver(target, QEvent.MouseMove, moved, button=Qt.NoButton, buttons=Qt.LeftButton)
+    deliver(target, QEvent.MouseMove, moved, button=Qt.NoButton, buttons=Qt.LeftButton)
+    geo1 = w.geometry()
+    deliver(target, QEvent.MouseButtonRelease, moved,
+            button=Qt.LeftButton, buttons=Qt.NoButton)
+    assert w._resize_edge == "", "release 后 _resize_edge 未清空"
+    return type(target).__name__, geo0, geo1
+
+
 def main():
     app = QApplication(sys.argv)
     # 在 offscreen 平台，默认屏幕可能很小（800x600），把窗口放大会被限制
@@ -43,7 +75,7 @@ def main():
     orig_primary = QApplication.primaryScreen
     QApplication.primaryScreen = staticmethod(lambda: FakeScreen())
 
-    print("[1/5] 创建 MainWindow + 边缘 hit-test")
+    print("[1/8] 创建 MainWindow + 边缘 hit-test")
     w = MainWindow()
     w.resize(800, 600)
     w.show()
@@ -66,7 +98,7 @@ def main():
     assert w._hit_test_edge(QPoint(w_real_w - 2, w_real_h - 2)) == "BR"
     print("  ✓ 8 个区域（4 边 + 4 角）全部正确命中")
 
-    print("[2/5] 普通模式：拖右边缘放大窗口")
+    print("[2/8] 普通模式：拖右边缘放大窗口")
     w.resize(800, 600)
     w.show()
     rw, rh = w.width(), w.height()
@@ -87,7 +119,7 @@ def main():
     assert w._resize_edge == ""
     print(f"  ✓ 右拖: 宽 {geo0.width()} → {geo1.width()} (+{geo1.width() - geo0.width()})")
 
-    print("[3/5] 普通模式：拖左边缘（鼠标右移 → 窗口变宽）")
+    print("[3/8] 普通模式：拖左边缘（鼠标右移 → 窗口变宽）")
     w.resize(800, 600)
     w.show()
     rw, rh = w.width(), w.height()
@@ -111,7 +143,7 @@ def main():
     assert geo1.x() > geo0.x(), f"x 没变: {geo0.x()} -> {geo1.x()}"
     QApplication.sendEvent(w, make_mouse_event(QEvent.MouseButtonRelease, new_pos))
 
-    print("[4/5] 普通模式：拖角（左上）")
+    print("[4/8] 普通模式：拖角（左上）")
     w.resize(800, 600)
     w.show()
     rw, rh = w.width(), w.height()
@@ -131,7 +163,7 @@ def main():
         print(f"  ✓ TL 拖: {geo0.width()}x{geo0.height()} → {geo1.width()}x{geo1.height()} (受 minSize 限制)")
     QApplication.sendEvent(w, make_mouse_event(QEvent.MouseButtonRelease, new_pos))
 
-    print("[5/5] 最大化时：拖顶部边缘应还原窗口")
+    print("[5/8] 最大化时：拖顶部边缘应还原窗口（直接投递路径）")
     w.resize(800, 600)
     w.showMaximized()
     app.processEvents()
@@ -149,6 +181,73 @@ def main():
     QApplication.sendEvent(w, make_mouse_event(QEvent.MouseButtonRelease, QPoint(400, 3)))
     print(f"  ✓ 最大化时点顶部 → 已还原 (geometry={w.geometry().width()}x{w.geometry().height()})")
 
+    print("[6/8] 真实事件投递：4 边 + 3 角都能拖动（经子控件传播/事件过滤器）")
+    cases = [
+        # (名称, 按压点函数, 拖动增量, 期望 edge, 断言函数)
+        ("L",  lambda W, H: QPoint(3, H // 2),      (60, 0),   "L",
+         lambda g0, g1: g1.x() > g0.x()),
+        ("R",  lambda W, H: QPoint(W - 4, H // 2),  (60, 0),   "R",
+         lambda g0, g1: g1.width() > g0.width()),
+        ("T",  lambda W, H: QPoint(W // 2, 3),      (0, 60),   "T",
+         lambda g0, g1: g1.y() > g0.y()),
+        ("B",  lambda W, H: QPoint(W // 2, H - 4),  (0, 60),   "B",
+         lambda g0, g1: g1.height() > g0.height()),
+        ("TL", lambda W, H: QPoint(3, 3),           (60, 60),  "TL",
+         lambda g0, g1: g1.x() > g0.x() and g1.y() > g0.y()),
+        ("TR", lambda W, H: QPoint(W - 4, 3),       (-60, 60), "TR",
+         lambda g0, g1: g1.y() > g0.y()),
+        ("BL", lambda W, H: QPoint(3, H - 4),       (60, -60), "BL",
+         lambda g0, g1: g1.x() > g0.x()),
+    ]
+    for name, pos_fn, delta, edge, check in cases:
+        w.resize(800, 600)
+        w.show()
+        app.processEvents()
+        W, H = w.width(), w.height()
+        hit, geo0, geo1 = try_real_drag(w, pos_fn(W, H), delta, edge)
+        assert check(geo0, geo1), \
+            f"{name}: 几何未生效 {geo0.getRect()} → {geo1.getRect()} (命中 {hit})"
+        print(f"  ✓ {name:2s} 命中 {hit:10s} → {geo0.width()}x{geo0.height()} "
+              f"→ {geo1.width()}x{geo1.height()}")
+    # BR：原生 QSizeGrip 负责（真实桌面可拖；offscreen 下只验证 grip 存在且不被过滤器拦截）
+    w.resize(800, 600)
+    w.show()
+    app.processEvents()
+    br_child = w.childAt(QPoint(w.width() - 4, w.height() - 4))
+    assert isinstance(br_child, QSizeGrip), f"右下角应为 QSizeGrip, 实际 {type(br_child).__name__}"
+    print(f"  ✓ BR 命中 QSizeGrip（原生角拖保留）")
+
+    print("[7/8] 最大化时：真实按压菜单栏顶缘 → 还原（事件过滤器路径）")
+    w.resize(800, 600)
+    w.showMaximized()
+    app.processEvents()
+    assert w.isMaximized()
+    mb = w.menuBar()
+    local = QPoint(mb.width() // 2, 2)  # 菜单栏局部坐标，顶缘 6px 带内
+    deliver(mb, QEvent.MouseButtonPress, local,
+            button=Qt.LeftButton, buttons=Qt.LeftButton)
+    app.processEvents()
+    assert not w.isMaximized(), "事件过滤器路径：最大化时按菜单栏顶缘应还原"
+    deliver(mb, QEvent.MouseButtonRelease, local,
+            button=Qt.LeftButton, buttons=Qt.NoButton)
+    assert w._resize_edge == ""
+    print(f"  ✓ 菜单栏顶缘按压 → 已还原 ({w.width()}x{w.height()})")
+
+    print("[8/8] 最小尺寸合理性（回归：曾被 MinimumSizeHint 撑到 1121px 高）")
+    assert w.minimumWidth() <= 800, f"最小宽度异常: {w.minimumWidth()}"
+    assert w.minimumHeight() <= 600, f"最小高度异常: {w.minimumHeight()}"
+    w.resize(1280, 800)
+    app.processEvents()
+    assert w.width() == 1280 and w.height() == 800, \
+        f"resize(1280,800) 被 clamp 成 {w.width()}x{w.height()}"
+    # 能缩小到最小尺寸
+    w.resize(760, 480)
+    app.processEvents()
+    assert w.width() == 760 and w.height() == 480, \
+        f"无法缩到下限: {w.width()}x{w.height()}"
+    print(f"  ✓ minimumSize={w.minimumWidth()}x{w.minimumHeight()}, "
+          f"resize(1280,800)/resize(760,480) 均精确生效")
+
     print("\n窗口边缘拖动测试通过 ✓")
 
 

ui/main_window.py

@@ -7,7 +7,7 @@ import sys
 import time
 from typing import Optional
 
-from PyQt5.QtCore import Qt, QSize
+from PyQt5.QtCore import Qt, QSize, QEvent
 from PyQt5.QtGui import QFont, QIcon
 from PyQt5.QtWidgets import (
     QMainWindow, QWidget, QVBoxLayout, QHBoxLayout, QListWidget, QListWidgetItem,
@@ -47,6 +47,13 @@ class MainWindow(QMainWindow):
         self._build_menu()
         self._build_statusbar()
 
+        # 菜单栏/状态栏事件过滤器：
+        # 窗口上下边缘分别被 QMenuBar / QStatusBar 覆盖，QMenuBar 会主动消费
+        # 鼠标事件（悬停高亮菜单），事件不会传播到 QMainWindow，导致上边缘
+        # （及最大化时从顶部拖还原）永远失效。装过滤器在边缘带内截获处理。
+        self.menuBar().installEventFilter(self)
+        self.statusBar().installEventFilter(self)
+
         # 左侧主机栏折叠状态
         # 注意：Ctrl+B 快捷键只由「视图」菜单项（act_toggle_sidebar）承载，
         # 不再额外建 QShortcut —— 否则一次按键触发两个绑定，会 toggle 两次等于没反应
@@ -172,6 +179,16 @@ class MainWindow(QMainWindow):
         splitter.addWidget(self.tabs)
         splitter.setSizes([280, 1000])
 
+        # 各 Tab 页显式设小最小尺寸：否则 QTabWidget 取所有页 minimumSizeHint
+        # 的最大值（MonitorPanel 内部表格/分组堆出 ~1015px 高），一路传到
+        # QMainWindow，导致窗口最小高度 > 1100px —— 上下边缘拖动被 clamp 死，
+        # 表现为"上下不能拉"。QSplitter 子件默认 minimumSize=0，压缩无碍。
+        for _page in (self.terminal_panel, self.file_browser,
+                      self.monitor, self.ai_panel):
+            _page.setMinimumSize(320, 200)
+        # 窗口级合理下限（显式 minimumSize 覆盖布局算出的巨大值）
+        self.setMinimumSize(760, 480)
+
     def _toggle_sidebar(self):
         """折叠/展开左侧主机栏"""
         self._sidebar_collapsed = not self._sidebar_collapsed
@@ -620,7 +637,7 @@ class MainWindow(QMainWindow):
             return "B"
         return ""
 
-    def _edge_to_cursor(self, edge: str):
+    def _edge_to_cursor(self, edge: str, widget=None):
         from PyQt5.QtGui import QCursor
         from PyQt5.QtCore import Qt as _Qt
         cursors = {
@@ -631,10 +648,58 @@ class MainWindow(QMainWindow):
         }
         c = cursors.get(edge)
         if c is not None:
-            self.setCursor(QCursor(c))
+            (widget or self).setCursor(QCursor(c))
 
-    def _restore_cursor(self):
+    def _restore_cursor(self, widget=None):
-        self.unsetCursor()
+        (widget or self).unsetCursor()
+
+    def eventFilter(self, obj, e):
+        """拦截菜单栏/状态栏上的鼠标事件，实现上/下边缘拖动调整窗口。
+
+        QMenuBar 主动消费鼠标事件（悬停高亮菜单项），事件不会向上传播到
+        QMainWindow，上边缘 hit-test 永远收不到事件；状态栏在部分平台/样式
+        下同理。过滤器只在 6px 边缘带内接管，其余区域原样放行
+        （菜单照常点开、QSizeGrip 原生右下角拖动不受影响）。
+        """
+        mb, sb = self.menuBar(), self.statusBar()
+        if obj is mb or obj is sb:
+            et = e.type()
+            if et == QEvent.MouseMove:
+                # 拖动中：press 时已 grabMouse，move 持续走这里
+                if self._resize_edge and (e.buttons() & Qt.LeftButton):
+                    self._do_resize(e.globalPos())
+                    return True
+                # 悬停：边缘带内显示调整光标并屏蔽菜单高亮，带外放行
+                if not e.buttons():
+                    edge = self._hit_test_edge(obj.mapTo(self, e.pos()))
+                    if edge:
+                        self._edge_to_cursor(edge, obj)
+                        return True
+                    self._restore_cursor(obj)
+                return False
+            if et == QEvent.MouseButtonPress and e.button() == Qt.LeftButton:
+                # 最大化时：菜单栏顶部边缘按下 → 还原并跟随鼠标
+                if obj is mb and self.isMaximized() and e.pos().y() <= self._resize_margin:
+                    self._restore_from_max(e.globalPos())
+                    return True
+                edge = self._hit_test_edge(obj.mapTo(self, e.pos()))
+                if edge:
+                    self._resize_edge = edge
+                    self._resize_start_geo = self.geometry()
+                    self._resize_start_pos = e.globalPos()
+                    obj.grabMouse()  # 后续 move/release 全部经过本过滤器
+                    return True
+                return False
+            if et == QEvent.MouseButtonRelease and self._resize_edge:
+                self._resize_edge = ""
+                self._resize_start_geo = None
+                self._resize_start_pos = None
+                obj.releaseMouse()
+                return True
+            if et == QEvent.Leave:
+                self._restore_cursor(obj)
+                return False
+        return super().eventFilter(obj, e)
 
     def mouseMoveEvent(self, e):
         # 拖动中