1 files changed, 74 insertions, 0 deletions
diff --git a/core/reference_registry.py b/core/reference_registry.py
new file mode 100644
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--- /dev/null
+++ b/core/reference_registry.py
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+"""
+core/reference_registry.py
+
+Generic (device_id, channel_id) reference-rename propagation.
+
+A Signal (physical device channel) or a Channel (derived, device_id ==
+"derived") can be renamed by the user. Both kinds are referenced the same
+way everywhere downstream — plot traces, control targets, filter
+pipelines, other derived channels' sources — as a plain
+(device_id, channel_id) pair. Renaming one without rewriting every
+reference to it leaves those references dangling: they silently stop
+receiving data (this is exactly the bug that motivated this module — an
+Arduino analog pin remap changed a Signal's id and orphaned its plot
+trace).
+
+propagate_rename() is the single place that walks every subsystem able to
+hold such a reference and rewrites it. It expects a MainWindow instance
+(or anything exposing the same .engine/.processor/._chart/._ctrl/
+._win_config attributes) since that's the one place all of them are
+reachable from.
+"""
+
+from typing import Tuple
+
+Ref = Tuple[str, str]
+
+
+def propagate_rename(app, old_ref: Ref, new_ref: Ref) -> None:
+    if old_ref == new_ref:
+        return
+
+    # Physical signals live in the acquisition engine's buffers; derived
+    # Channels don't (their buffers live in SignalProcessor._derived_bufs).
+    if old_ref[0] != "derived":
+        app.engine.rename_channel(old_ref[0], old_ref[1], new_ref[1])
+
+    # Filter pipelines, other derived channels' sources, latest-value cache,
+    # and (if old_ref is itself a derived Channel) its ring buffer.
+    app.processor.rename_reference(old_ref, new_ref)
+
+    # Live plot — trace specs in the strip chart's current layout.
+    chart = getattr(app, "_chart", None)
+    changed = False
+    if chart is not None and chart._cfg is not None:
+        for pane in chart._cfg.panes:
+            for tr in pane.traces:
+                if (tr.device_id, tr.channel_id) == old_ref:
+                    tr.device_id, tr.channel_id = new_ref
+                    changed = True
+    if changed:
+        chart.refresh()
+
+    # Control panel — saved specs (profile persistence) + live bound widgets
+    # (actual I/O routing — ControlWidget reads its own .device_id/.channel_id
+    # directly in _write()/_check_stale(), not from the spec).
+    ctrl = getattr(app, "_ctrl", None)
+    if ctrl is not None:
+        for spec in ctrl.get_specs():
+            if (spec.device_id, spec.channel_id) == old_ref:
+                spec.device_id, spec.channel_id = new_ref
+        for widget in getattr(ctrl, "_widgets", []):
+            if (widget.device_id, widget.channel_id) == old_ref:
+                widget.device_id, widget.channel_id = new_ref
+
+    # Config window tabs, if currently open — refresh so pickers/tables
+    # don't show the stale id until next full refresh.
+    win = getattr(app, "_win_config", None)
+    if win is not None:
+        if chart is not None:
+            win.refresh_plot(chart._cfg)
+        if hasattr(win, "refresh_derived"):
+            win.refresh_derived()
+        if hasattr(win, "refresh_devices"):
+            win.refresh_devices()