Implement resizing semantics based on layout

Still need to do splits layout but all others should be OK

kitty/boss.py

@@ -2427,13 +2427,17 @@ class Boss:
         self, edges: int, x: float, y: float, window_id: int, cell_width: int, cell_height: int,
     ) -> bool:
         if (w := self.window_id_map.get(window_id)) and (tab := w.tabref()):
-            horizontal, vertical = tab.current_layout.drag_resize_target_windows(w, x, y, tab.windows)
+            horizontal, width_increases_rightwards, vertical, height_increases_downwards = \
+                    tab.current_layout.drag_resize_target_windows(w, x, y, edges, tab.windows)
             horizontal_allowed = bool(edges & (LEFT_EDGE | RIGHT_EDGE))
             vertical_allowed = bool(edges & (TOP_EDGE | BOTTOM_EDGE))
             self.drag_resize_of_window = WindowResizeDrag(
                 is_active=True, horizontal_target_window_id=horizontal.id if horizontal_allowed else 0,
                 vertical_target_window_id=vertical.id if vertical_allowed else 0,
-                cell_width=cell_width, cell_height=cell_height, initial_x=x, initial_y=y)
+                cell_width=cell_width, cell_height=cell_height, initial_x=x, initial_y=y,
+                width_increases_rightwards=width_increases_rightwards,
+                height_increases_downwards=height_increases_downwards,
+            )
             return True
         return False
 
@@ -2441,18 +2445,20 @@ class Boss:
         if not (r := self.drag_resize_of_window):
             return
         if h := self.window_id_map.get(r.horizontal_target_window_id):
-            step_x = floor((x - r.initial_x) / r.cell_width)
+            mult = 1 if r.width_increases_rightwards else -1
+            step_x = floor((x - r.initial_x) / r.cell_width) * mult
             dx = step_x - r.last_step_x
             if dx != 0:
-                self.resize_layout_window(h, float(dx), True, False)
-                self.drag_resize_of_window = r._replace(last_step_x=step_x)
+                if self.resize_layout_window(h, float(dx), is_horizontal=True) is None:
+                    self.drag_resize_of_window = r._replace(last_step_x=step_x)
 
         if v := self.window_id_map.get(r.vertical_target_window_id):
-            step_y = floor((y - r.initial_y) / r.cell_height)
+            mult = 1 if r.height_increases_downwards else -1
+            step_y = floor((y - r.initial_y) / r.cell_height) * mult
             dy = step_y - r.last_step_y
             if dy != 0:
-                self.resize_layout_window(v, float(dy), False, False)
-                self.drag_resize_of_window = r._replace(last_step_y=step_y)
+                if self.resize_layout_window(v, float(dy), is_horizontal=False) is None:
+                    self.drag_resize_of_window = r._replace(last_step_y=step_y)
 
     def drag_resize_end(self) -> None:
         self.drag_resize_of_window = WindowResizeDrag()

kitty/layout/base.py

@@ -7,7 +7,7 @@ from itertools import repeat
 from typing import Any, Callable, NamedTuple
 
 from kitty.borders import BorderColor
-from kitty.fast_data_types import Region, get_options, set_active_window, viewport_for_window
+from kitty.fast_data_types import BOTTOM_EDGE, RIGHT_EDGE, Region, get_options, set_active_window, viewport_for_window
 from kitty.options.types import Options
 from kitty.types import Edges, NeighborsMap, WindowGeometry, WindowMapper
 from kitty.typing_compat import WindowType
@@ -453,31 +453,9 @@ class Layout:
         return True
 
     def drag_resize_target_windows(
-            self, click_window: WindowType, x: float, y: float, all_windows: WindowList
-    ) -> tuple[WindowType, WindowType]:
-        g = click_window.geometry
-        left_half_clicked = x <= g.left + (g.right - g.left) / 2
-        top_half_clicked = y <= g.top + (g.bottom - g.top) / 2
-        neighbors = self.neighbors_for_window(click_window, all_windows)
-        left = neighbors.get("left", ())
-        right = neighbors.get("right", ())
-        top = neighbors.get("top", ())
-        bottom = neighbors.get("bottom", ())
-        horizontal_target = vertical_target = click_window
-
-        # Infer which window should be horizontally resized based on click
-        # position and layout state
-        if ((left_half_clicked and len(left) > 0) or
-            (not left_half_clicked and len(left) > 0 and len(right) == 0)):
-            horizontal_target = all_windows.id_map[left[0]]
-
-        # Infer which window should be vertically resized based on click
-        # position and layout state
-        if ((top_half_clicked and len(top) > 0) or
-            (not top_half_clicked and len(top) > 0 and len(bottom) == 0)):
-            vertical_target = all_windows.id_map[top[0]]
-
-        return horizontal_target, vertical_target
+        self, click_window: WindowType, x: float, y: float, edges: int, all_windows: WindowList,
+    ) -> tuple[WindowType, bool, WindowType, bool]:
+        return click_window, bool(edges & RIGHT_EDGE), click_window, bool(edges & BOTTOM_EDGE)
 
     def serialize(self, all_windows: WindowList) -> dict[str, Any]:
         ans = self.layout_state()

kitty/layout/tall.py

@@ -1,12 +1,14 @@
 #!/usr/bin/env python
 # License: GPLv3 Copyright: 2020, Kovid Goyal <kovid at kovidgoyal.net>
 
+import sys
 from collections.abc import Generator, Sequence
 from itertools import islice, repeat
 from typing import Any
 
 from kitty.borders import BorderColor
 from kitty.conf.utils import to_bool
+from kitty.fast_data_types import BOTTOM_EDGE, RIGHT_EDGE
 from kitty.types import Edges, NeighborsMap, WindowMapper
 from kitty.typing_compat import EdgeLiteral, WindowType
 from kitty.window_list import WindowGroup, WindowList
@@ -24,6 +26,36 @@ from .base import (
 from .vertical import borders
 
 
+def drag_resize_target_windows(
+        click_window: WindowType,
+        edges: int,
+        x: float, y: float,
+        num_full_size_windows: int,
+        all_windows: WindowList,
+        main_is_horizontal: bool = True
+) -> tuple[WindowType, bool, WindowType, bool]:
+    groups = tuple(all_windows.iter_all_layoutable_groups())
+    horizontal = vertical = click_window
+    min_dist = float(sys.maxsize)
+    height_increases_downwards = bool(edges * BOTTOM_EDGE)
+    width_increases_rightwards = bool(edges * RIGHT_EDGE)
+    for gr in groups[num_full_size_windows:]:
+        if gr.windows:
+            w = gr.windows[-1]
+            g = w.geometry
+            if main_is_horizontal:
+                if (dist := min(abs(g.top - y), abs(g.bottom - y))) < min_dist:
+                    min_dist = dist
+                    vertical = w
+                    height_increases_downwards = y > g.top + (g.bottom - g.top) / 2
+            else:
+                if (dist := min(abs(g.left - x), abs(g.right - x))) < min_dist:
+                    min_dist = dist
+                    horizontal = w
+                    width_increases_rightwards = x > g.left + (g.right - g.left) / 2
+    return horizontal, width_increases_rightwards, vertical, height_increases_downwards
+
+
 def neighbors_for_tall_window(
         num_full_size_windows: int,
         window: WindowType,
@@ -357,6 +389,11 @@ class Tall(Layout):
         self.layout_opts = TallLayoutOpts(layout_state['opts'])
         return True
 
+    def drag_resize_target_windows(
+        self, click_window: WindowType, x: float, y: float, edges: int, all_windows: WindowList,
+    ) -> tuple[WindowType, bool, WindowType, bool]:
+        return drag_resize_target_windows(click_window, edges, x, y, self.num_full_size_windows, all_windows, self.main_is_horizontal)
+
 
 class Fat(Tall):
 

kitty/types.py

@@ -253,6 +253,8 @@ class WindowResizeDrag(NamedTuple):
     initial_y: float = 0
     last_step_x: float = 0
     last_step_y: float = 0
+    height_increases_downwards: bool = True
+    width_increases_rightwards: bool = True
 
     def __bool__(self) -> bool:
         return self.is_active