Implement z-layers (#98)

counterweight/app.py

@@ -16,7 +16,6 @@
 from counterweight._context_vars import current_event_queue
 from counterweight._utils import drain_queue
 from counterweight.border_healing import heal_borders
-from counterweight.cell_paint import CellPaint
 from counterweight.components import Component, component
 from counterweight.controls import AnyControl, Bell, Quit, Screenshot, Suspend, ToggleBorderHealing, _Control
 from counterweight.elements import AnyElement, Div
@@ -43,15 +42,10 @@
     stop_mouse_tracking,
     stop_output_control,
 )
-from counterweight.paint import Paint, paint_layout, svg
+from counterweight.paint import BLANK, Paint, paint_layout, svg
 from counterweight.shadow import ShadowNode, update_shadow
 from counterweight.styles import Span, Style
-from counterweight.styles.styles import CellStyle, Color, Flex
-
-BLANK = CellPaint(
-    char=" ",
-    style=CellStyle(background=Color.from_name("black")),
-)
+from counterweight.styles.styles import Flex
 
 logger = get_logger()
 

counterweight/border_healing.py

@@ -2,9 +2,8 @@
 
 from functools import lru_cache
 
-from counterweight.cell_paint import CellPaint
 from counterweight.geometry import Position
-from counterweight.paint import Paint
+from counterweight.paint import P, Paint
 from counterweight.styles.styles import JoinedBorderKind, JoinedBorderParts
 
 
@@ -40,15 +39,15 @@ def dither(position: Position) -> tuple[Position, Position, Position, Position]:
 
 def heal_borders(paint: Paint) -> Paint:
     overlay: Paint = {}
-    for p, cell_paint in paint.items():
-        char = cell_paint.char
+    for pos, p in paint.items():
+        char = p.char
         for kind in JOINED_BORDER_KINDS:
             if char not in kind:  # the center character must be a joined border part
                 continue
 
-            left, right, above, below = map(paint.get, dither(p))
+            left, right, above, below = map(paint.get, dither(pos))
 
-            # TODO: cell styles must match too (i.e., colors)
+            # TODO: cell styles and z-levels must match too (i.e., colors)
 
             if replaced_char := get_replacement_char(
                 kind,
@@ -58,6 +57,6 @@ def heal_borders(paint: Paint) -> Paint:
                 above=above.char if above else None,
                 below=below.char if below else None,
             ):
-                overlay[p] = CellPaint(char=replaced_char, style=cell_paint.style)
+                overlay[pos] = P(char=replaced_char, style=p.style, z=p.z)
 
     return overlay

counterweight/elements.py

@@ -1,11 +1,11 @@
 from __future__ import annotations
 
+from dataclasses import dataclass, field
 from functools import cached_property
 from typing import Callable, Literal, Sequence, Union
 
 from pydantic import Field
 
-from counterweight.cell_paint import CellPaint
 from counterweight.controls import AnyControl
 from counterweight.events import KeyPressed, MouseDown, MouseUp
 from counterweight.styles import CellStyle, Style
@@ -73,3 +73,9 @@ def cells(self) -> tuple[CellPaint, ...]:
 
 Div.model_rebuild()
 Text.model_rebuild()
+
+
+@dataclass(slots=True)
+class CellPaint:
+    char: str
+    style: CellStyle = field(default=CellStyle())

counterweight/geometry.py

@@ -1,7 +1,9 @@
 from __future__ import annotations
 
+from collections.abc import Iterator
 from dataclasses import dataclass, field
 from functools import lru_cache
+from itertools import product
 from typing import NamedTuple
 
 
@@ -36,6 +38,9 @@ def x_range(self) -> range:
     def y_range(self) -> range:
         return range(self.y, self.y + self.height)
 
+    def xy_range(self) -> Iterator[tuple[int, int]]:
+        return product(self.x_range(), self.y_range())
+
     @property
     def left(self) -> int:
         return self.x

counterweight/layout.py

@@ -2,14 +2,14 @@
 
 from collections.abc import Iterator
 from dataclasses import dataclass, field
+from typing import Iterable, Literal
 
 from more_itertools import take
 from structlog import get_logger
 
 from counterweight._utils import halve_integer, partition_int
-from counterweight.cell_paint import wrap_cells
 from counterweight.components import Component
-from counterweight.elements import AnyElement
+from counterweight.elements import AnyElement, CellPaint
 from counterweight.geometry import Edge, Rect
 from counterweight.styles.styles import BorderEdge
 
@@ -63,6 +63,11 @@ class LayoutBox:
     children: list[LayoutBox] = field(default_factory=list)
     dims: LayoutBoxDimensions = field(default_factory=LayoutBoxDimensions)
 
+    def walk_from_top(self) -> Iterator[LayoutBox]:
+        yield self
+        for child in self.children:
+            yield from child.walk_from_top()
+
     def walk_from_bottom(self) -> Iterator[LayoutBox]:
         for child in self.children:
             yield from child.walk_from_bottom()
@@ -432,3 +437,37 @@ def build_layout_tree_from_concrete_element_tree(element: AnyElement, parent: La
     )
 
     return box
+
+
+def wrap_cells(
+    cells: Iterable[CellPaint],
+    wrap: Literal["none", "paragraphs"],
+    width: int,
+) -> list[list[CellPaint]]:
+    if width <= 0:
+        return []
+
+    if wrap == "none":
+        lines: list[list[CellPaint]] = []
+        current_line: list[CellPaint] = []
+        for cell in cells:
+            if cell.char == "\n":
+                lines.append(current_line)
+                current_line = []
+            else:
+                current_line.append(cell)
+        lines.append(current_line)
+        return lines
+
+    raise NotImplementedError("non-none wrapping not yet implemented")
+
+    # wrapper = TextWrapper(width=width)
+    #
+    # paragraphs = text.split("\n\n")  # double newline = paragraph break
+    #
+    # lines = []
+    # for paragraph in paragraphs:
+    #     lines.extend(wrapper.wrap(paragraph))
+    #     lines.append("")  # empty line between paragraphs
+    #
+    # return lines[:-1]  # remove last empty line

counterweight/output.py

@@ -1,11 +1,15 @@
-from typing import TextIO
+from __future__ import annotations
+
+from typing import TYPE_CHECKING, TextIO
 
 from structlog import get_logger
 
 from counterweight.geometry import Position
 from counterweight.paint import Paint
 from counterweight.styles.styles import CellStyle
 
+if TYPE_CHECKING:
+    pass
 # https://www.xfree86.org/current/ctlseqs.html
 # https://invisible-island.net/xterm/ctlseqs/ctlseqs.pdf