feat: added a twist

backend/uframe/emit_micron.py

@@ -0,0 +1,121 @@
+"""Micron emitter — read CharGrid and output Micron markup with style tags.
+
+Scans each line left-to-right, tracks style state, and opens/closes
+Micron format codes at style transitions. Box-drawing characters pass
+through as literal text.
+
+Micron format reference:
+  `!bold`!   `*italic`*   `_underline`_
+  `Fhex text`f   `Bhex text`b
+  `c center`a   `r right`a
+  [label`dest]   [label`dest.mu]
+  >H1   >>H2   >>>H3
+"""
+
+from __future__ import annotations
+
+from uframe.grid import CharGrid, CellStyle
+from uframe.ir import Page, Heading, HeadingLevel
+
+
+def _emit_style_open(style: CellStyle) -> str:
+    """Emit Micron opening tags for a style."""
+    tags: list[str] = []
+    if style.bold:
+        tags.append("`!")
+    if style.italic:
+        tags.append("`*")
+    if style.underline:
+        tags.append("`_")
+    if style.fg:
+        tags.append(f"`F{style.fg}")
+    if style.bg:
+        tags.append(f"`B{style.bg}")
+    return "".join(tags)
+
+
+def _emit_style_close(style: CellStyle) -> str:
+    """Emit Micron closing tags for a style (in reverse order)."""
+    tags: list[str] = []
+    if style.bg:
+        tags.append("`b")
+    if style.fg:
+        tags.append("`f")
+    if style.underline:
+        tags.append("`_")
+    if style.italic:
+        tags.append("`*")
+    if style.bold:
+        tags.append("`!")
+    return "".join(tags)
+
+
+_EMPTY_STYLE = CellStyle()
+
+
+def emit_micron(grid: CharGrid, page_title: str = "") -> str:
+    """Emit the CharGrid as Micron markup.
+
+    Args:
+        grid: the rendered character grid
+        page_title: optional page title for a leading >Title line
+
+    Returns:
+        Micron source string
+    """
+    lines: list[str] = []
+
+    for row in range(grid.height):
+        line_parts: list[str] = []
+        cur_style = _EMPTY_STYLE
+        in_link: str | None = None
+
+        for col in range(grid.width):
+            cell = grid.cells[row][col]
+            ch = cell.char
+            style = cell.style
+            link = cell.link
+
+            # Handle link transitions
+            if link != in_link:
+                if in_link is not None:
+                    # Close previous link: [label`dest]
+                    line_parts.append(f"`{in_link}]")
+                if link is not None:
+                    # Close any open style before link
+                    if cur_style != _EMPTY_STYLE:
+                        line_parts.append(_emit_style_close(cur_style))
+                        cur_style = _EMPTY_STYLE
+                    # Open new link
+                    line_parts.append("[")
+                in_link = link
+
+            # Handle style transitions (not inside links — links handle their own style)
+            if link is None and style != cur_style:
+                # Close previous style
+                if cur_style != _EMPTY_STYLE:
+                    line_parts.append(_emit_style_close(cur_style))
+                # Open new style
+                if style != _EMPTY_STYLE:
+                    line_parts.append(_emit_style_open(style))
+                cur_style = style
+
+            line_parts.append(ch)
+
+        # Close any trailing link: [label`dest]
+        if in_link is not None:
+            line_parts.append(f"`{in_link}]")
+            in_link = None
+
+        # Close any trailing style
+        if cur_style != _EMPTY_STYLE:
+            line_parts.append(_emit_style_close(cur_style))
+
+        line = "".join(line_parts).rstrip()
+        lines.append(line)
+
+    # Strip trailing blank lines
+    while lines and not lines[-1]:
+        lines.pop()
+
+    return "\n".join(lines)