feat: image rendering — kitty graphics, sixel, and ASCII art backends

src/kitty_workbench/image_renderer.py

@@ -0,0 +1,76 @@
+"""Image rendering abstraction — kitty graphics, sixel, or ASCII art."""
+
+from __future__ import annotations
+
+import base64
+import shutil
+import subprocess
+import sys
+from pathlib import Path
+
+
+def render_image_kitty(path: str) -> str:
+    """Return kitty graphics protocol escape sequence for the image."""
+    data = Path(path).read_bytes()
+    b64 = base64.standard_b64encode(data).decode()
+    chunks = [b64[i:i + 4096] for i in range(0, len(b64), 4096)]
+    escape = ""
+    for i, chunk in enumerate(chunks):
+        m = 1 if i < len(chunks) - 1 else 0
+        if i == 0:
+            escape += f"\033_Ga=T,f=100,m={m};{chunk}\033\\"
+        else:
+            escape += f"\033_Gm={m};{chunk}\033\\"
+    return escape
+
+
+def render_image_sixel(path: str) -> str:
+    """Convert image to sixel using chafa or img2sixel."""
+    if shutil.which("chafa"):
+        result = subprocess.run(
+            ["chafa", "--format=sixel", "--size=80x40", str(path)],
+            capture_output=True, text=True,
+        )
+        if result.returncode == 0:
+            return result.stdout
+    if shutil.which("img2sixel"):
+        result = subprocess.run(
+            ["img2sixel", "-w", "640", str(path)],
+            capture_output=True, text=True,
+        )
+        if result.returncode == 0:
+            return result.stdout
+    return f"[Sixel unavailable — install chafa or libsixel. Image: {path}]"
+
+
+def render_image_ascii(path: str) -> str:
+    """Convert image to ASCII/Unicode block art using chafa."""
+    if shutil.which("chafa"):
+        result = subprocess.run(
+            ["chafa", "--size=60x30", str(path)],
+            capture_output=True, text=True,
+        )
+        if result.returncode == 0:
+            return result.stdout
+    return f"[Image: {path}]"
+
+
+def render_image(path: str, protocol: str) -> str:
+    """Render an image using the specified protocol. Returns terminal-ready string."""
+    p = Path(path)
+
+    if p.suffix.lower() == ".svg":
+        try:
+            import cairosvg
+            png_path = p.with_suffix(".png")
+            cairosvg.svg2png(url=str(p), write_to=str(png_path))
+            path = str(png_path)
+        except ImportError:
+            return f"[SVG display requires cairosvg: pip install cairosvg. File: {path}]"
+
+    if protocol == "kitty":
+        return render_image_kitty(path)
+    elif protocol == "sixel":
+        return render_image_sixel(path)
+    else:
+        return render_image_ascii(path)

src/kitty_workbench/tui.py

@@ -155,8 +155,10 @@ class KittWorkbenchApp(App):
         pane = self._get_pane(cmd.pane)
         if cmd.clear and not isinstance(pane, RichLog):
             pane.remove_children()
-        # Placeholder — image rendering added in Task 7
-        pane.mount(Static(f"[Image: {cmd.path}]"))
+
+        from kitty_workbench.image_renderer import render_image
+        rendered = render_image(cmd.path, self._image_protocol)
+        pane.mount(Static(rendered, markup=False))
 
     def _handle_log(self, cmd: LogCmd) -> None:
         try: