1 files changed, 108 insertions, 0 deletions
diff --git a/modules/desktop/eww/activate-windows.py b/modules/desktop/eww/activate-windows.py
new file mode 100644
index 0000000..b0dba4a
--- /dev/null
+++ b/modules/desktop/eww/activate-windows.py
@@ -0,0 +1,108 @@
+#!/usr/bin/env python3
+"""active-windows: emit icons for windows on the currently active
+niri workspace, driven by niri's event-stream instead of polling."""
+import json
+import subprocess
+import gi
+from gi.repository import Gio, Gtk
+
+gi.require_version("Gtk", "3.0")
+
+icon_theme = Gtk.IconTheme.get_default()
+_icon_cache: dict[str, str] = {}
+
+
+def resolve_icon_path(app_id: str) -> str:
+    if not app_id:
+        return ""
+    if app_id in _icon_cache:
+        return _icon_cache[app_id]
+
+    app_info = Gio.DesktopAppInfo.new(f"{app_id}.desktop") \
+        or Gio.DesktopAppInfo.new(f"{app_id.lower()}.desktop")
+
+    # fall back: scan installed .desktop files for a matching StartupWMClass
+    if app_info is None:
+        for info in Gio.AppInfo.get_all():
+            if isinstance(info, Gio.DesktopAppInfo):
+                wm_class = info.get_startup_wm_class()
+                if wm_class and wm_class.lower() == app_id.lower():
+                    app_info = info
+                    break
+
+    icon_path = ""
+    gicon = app_info.get_icon() if app_info else None
+    if gicon is not None:
+        lookup = icon_theme.lookup_by_gicon(gicon,
+                                            32,
+                                            Gtk.IconLookupFlags.FORCE_SIZE)
+        if lookup:
+            icon_path = lookup.get_filename() or ""
+
+    if not icon_path:
+        # last resort: treat app_id itself as an icon-theme name
+        lookup = icon_theme.lookup_icon(app_id,
+                                        32,
+                                        Gtk.IconLookupFlags.FORCE_SIZE)
+        if lookup:
+            icon_path = lookup.get_filename() or ""
+
+    _icon_cache[app_id] = icon_path
+    return icon_path
+
+
+def niri_json(*args):
+    out = subprocess.run(["niri", "msg", "-j", *args],
+                         capture_output=True,
+                         text=True,
+                         check=True)
+    return json.loads(out.stdout)
+
+
+def emit_active_windows():
+    workspaces = niri_json("workspaces")
+    windows = niri_json("windows")
+
+    active_ws = next((w for w in workspaces if w.get("is_active")), None)
+    active_id = active_ws["id"] if active_ws else None
+
+    result = [
+        {
+            "id": w["id"],
+            "title": w.get("title", ""),
+            "app_id": w.get("app_id") or "",
+            "is_focused": w.get("is_focused", False),
+            "icon": resolve_icon_path(w.get("app_id") or ""),
+        }
+        for w in windows
+        if w.get("workspace_id") == active_id
+    ]
+    print(json.dumps(result), flush=True)
+
+
+RELEVANT_EVENTS = {
+    "WindowOpenedOrChanged", "WindowClosed", "WindowFocusChanged",
+    "WorkspaceActivated", "WorkspacesChanged", "WindowsChanged",
+}
+
+
+def main():
+    emit_active_windows()
+    proc = subprocess.Popen(
+        ["niri", "msg", "-j", "event-stream"],
+        stdout=subprocess.PIPE, text=True, bufsize=1,
+    )
+    for line in proc.stdout:
+        try:
+            key = next(iter(json.loads(line)))
+        except (json.JSONDecodeError, StopIteration):
+            continue
+        if key in RELEVANT_EVENTS:
+            try:
+                emit_active_windows()
+            except subprocess.CalledProcessError:
+                pass
+
+
+if __name__ == "__main__":
+    main()