WIP rich log 2

src/textual/widgets/_rich_log2.py

@@ -0,0 +1,151 @@
+from __future__ import annotations
+
+from dataclasses import dataclass, field
+from itertools import islice
+
+from rich.console import RenderableType
+
+from textual.cache import LRUCache
+from textual.reactive import var
+from textual.scroll_view import ScrollView
+from textual.strip import Strip
+from textual.style import Style
+from textual.visual import Visual, visualize
+
+
+class _HeightMap:
+
+    def __init__(self) -> None:
+        self.lines: list[tuple[int, int]]
+        self.item_to_line: dict[int, int] = {}
+        self.item_heights: dict[int, int] = {}
+
+    def get_line_range(self, line_no: int, count: int) -> list[tuple[int, int]]:
+        return self.lines[line_no : line_no + count]
+
+    def add_item(self, item_id: int, height: int) -> None:
+        self.item_to_line[item_id] = len(self.lines)
+        self.item_heights[item_id] = height
+        new_lines = [(item_id, line_offset) for line_offset in range(height)]
+        self.lines.extend(new_lines)
+
+    def update_item(self, item_id: int, height: int) -> None:
+        old_height = self.item_heights[item_id]
+        line_start = self.item_to_line[item_id]
+        self.item_heights[item_id] = height
+        height_change = height - old_height
+        if not height_change:
+            return
+        self.lines[line_start : line_start + old_height] = [
+            (item_id, line_offset) for line_offset in range(height)
+        ]
+        for line_no, (item_id, line_offset) in enumerate(
+            islice(self.lines, line_start + height, None), line_start + height
+        ):
+            if line_offset:
+                self.item_to_line[item_id] = line_no
+
+
+@dataclass
+class _HeightBucket:
+    start: int = 0
+    height: int = 0
+    items: list[tuple[int, int]] = field(default_factory=list)
+
+
+class _HeightMap:
+    def __init__(self, bucket_size: int = 100) -> None:
+        self._bucket_size = bucket_size
+        self._buckets: list[_HeightBucket] = [_HeightBucket()]
+        self.height = 0
+
+    def get_line_items(self, line_no: int, count: int) -> list[tuple[int, int]]:
+        """Get lines items for a given line range.
+
+        Args:
+            line_no (_type_): _description_
+            count (_type_): _description_
+
+        Returns:
+            List of tuples containing (ITEM ID, LINE OFFSET)
+        """
+        buckets = self._buckets
+        bucket_no = len(self._buckets) // 2
+
+        return []
+
+    def add_item(self, item_id: int, height: int) -> None:
+        line_no = self.height
+        for line_offset in range(line_no, line_no + height):
+            bucket = self._buckets[-1]
+            if bucket.height >= self._bucket_size:
+                bucket = _HeightBucket()
+                self._buckets.append(bucket)
+            bucket.items.append((item_id, line_offset))
+        self.height += height
+
+
+class RichLog(ScrollView, can_focus=True):
+    DEFAULT_CSS = """
+    RichLog{
+        background: $surface;
+        color: $foreground;
+        overflow-y: scroll;
+        &:focus {
+            background-tint: $foreground 5%;
+        }
+    }
+    """
+
+    max_lines: var[int | None] = var(None)
+    min_width: var[int] = var(78)
+    markup: var[bool] = var(False)
+
+    def __init__(
+        self,
+        *,
+        max_lines: int | None = None,
+        min_width: int = 78,
+        markup: bool = False,
+        auto_scroll: bool = True,
+        name: str | None = None,
+        id: str | None = None,
+        classes: str | None = None,
+        disabled: bool = False,
+    ) -> None:
+        """
+
+        Args:
+            max_lines: Maximum number of lines that may be scrolled, or `None` for no maximum.
+            min_width: Minimum width of lines.
+            markup: Enable content markup when writing text.
+            auto_scroll. Automatically scroll to newly written text.
+            name: The name of the widget.
+            id: The ID of the widget in the DOM.
+            classes: The CSS classes for the widget.
+            disabled: Whether the widget is disabled or not.
+        """
+        super().__init__(name=name, id=id, classes=classes, disabled=disabled)
+        self.max_lines = max_lines
+        self.min_width = min_width
+        self.markup = markup
+        self.auto_scroll = auto_scroll
+
+        self._item_id: int = 0
+        self.items: dict[int, Visual] = {}
+        # Cache key is (ITEM_ID, WIDTH, STYLE)
+        self._renders: LRUCache[tuple[int, int, Style], list[Strip]] = LRUCache(
+            maxsize=1024 * 2
+        )
+        self._height_map = _HeightMap()
+
+    def _render_item(self, width: int, item_id: int, style: Style) -> list[Strip]:
+        visual = self.items[item_id]
+        strips = visual.to_strips(self, visual, width, None, style)
+        self._renders[(item_id, width, style)] = strips
+        return strips
+
+    def write(self, content: Visual | RenderableType):
+        visual = visualize(self, content, markup=self.markup)
+        self.items[self._item_id] = visual
+        self._item_id += 1