generator: auto-expand declarative plug lists with per-channel mapper

Add build_plugs() to flow2json.py: a flow can declare a plugs: table
({id, name, channels?}) plus single_plugs/hold_plugs lists and the
generator emits all plumbing automatically — state-in node, /set out node,
dashboard widget, and (for multi-channel devices) a mapper function that
toggles each channel (state_1/state_2) instead of the ignored shared
{state:TOGGLE} payload.

Rewrite zigbee-monitor.yaml to the declarative form; Dual Outlet - Couch
is multi-channel (channels: [1,2]). Adding a plug is one line, no manual
node/wire duplication. Single press toggles 5 devices (couch via mapper
verified E2E ON/OFF), hold-release still DJ Booth only.

Refs: david/nr-flow-validator#2

flows/zigbee-monitor.yaml

@@ -5,17 +5,6 @@ brokers:
     host: mosquitto
     port: 1883
 
-# Plugs toggled on brief single press
-single_plugs:
-  - Squiggle
-  - Sideboard Lamp
-  - Bamboo Lights
-  - Dual Outlet - Couch
-
-# Plugs toggled on press-hold-release (action: "release" after a "hold")
-hold_plugs:
-  - DJ Booth
-
 dashboards:
   - base: Dashboard
     pages:
@@ -28,38 +17,35 @@ dashboards:
 
 flows:
   - tab: Zigbee Monitor
-    description: Button dispatches single vs hold-release to different plug sets
+    description: Button dispatches single vs hold-release to different plug sets.
+      Plug plumbing (state-in, /set out, dashboard widget, per-channel mapper)
+      is generated by flow2json.py from the plugs lists below.
+
+    # Declarative plug set. channels:[] marks a multi-channel device, which gets
+    # a mapper that toggles each channel and a widget showing each state_N.
+    plugs:
+      - id: squiggle
+        name: Squiggle
+      - id: sideboard
+        name: Sideboard Lamp
+      - id: bamboo
+        name: Bamboo Lights
+      - id: djbooth
+        name: DJ Booth
+      - id: couch
+        name: Dual Outlet - Couch
+        channels: [1, 2]
+
+    # Device ids toggled on brief single press (driven by single_filter)
+    single_plugs: [squiggle, sideboard, bamboo, couch]
+
+    # Device ids toggled on press-hold-release (driven by hold_filter)
+    hold_plugs: [djbooth]
+
+    single_filter: single-filter
+    hold_filter: hold-filter
+
     nodes:
-      - id: zigbee-state-squiggle
-        type: mqtt in
-        broker: mosquitto
-        topic: zigbee2mqtt/Squiggle
-        qos: 0
-
-      - id: zigbee-state-sideboard
-        type: mqtt in
-        broker: mosquitto
-        topic: zigbee2mqtt/Sideboard Lamp
-        qos: 0
-
-      - id: zigbee-state-bamboo
-        type: mqtt in
-        broker: mosquitto
-        topic: zigbee2mqtt/Bamboo Lights
-        qos: 0
-
-      - id: zigbee-state-djbooth
-        type: mqtt in
-        broker: mosquitto
-        topic: zigbee2mqtt/DJ Booth
-        qos: 0
-
-      - id: zigbee-state-couch
-        type: mqtt in
-        broker: mosquitto
-        topic: zigbee2mqtt/Dual Outlet - Couch
-        qos: 0
-
       - id: button-in
         type: mqtt in
         broker: mosquitto
@@ -100,73 +86,6 @@ flows:
           } catch (e) {}
           return null;
 
-      - id: plug-out-squiggle
-        type: mqtt out
-        broker: mosquitto
-        topic: zigbee2mqtt/Squiggle/set
-
-      - id: plug-out-sideboard
-        type: mqtt out
-        broker: mosquitto
-        topic: zigbee2mqtt/Sideboard Lamp/set
-
-      - id: plug-out-bamboo
-        type: mqtt out
-        broker: mosquitto
-        topic: zigbee2mqtt/Bamboo Lights/set
-
-      - id: plug-out-djbooth
-        type: mqtt out
-        broker: mosquitto
-        topic: zigbee2mqtt/DJ Booth/set
-
-      - id: couch-mapper
-        type: function
-        name: Toggle both outlets
-        code: |
-          msg.payload = { state_1: 'TOGGLE', state_2: 'TOGGLE' };
-          return msg;
-
-      - id: plug-out-couch
-        type: mqtt out
-        broker: mosquitto
-        topic: zigbee2mqtt/Dual Outlet - Couch/set
-
-      - id: text-squiggle
-        type: ui-text
-        group: Plugs
-        label: Squiggle
-        format: "{{msg.payload.state}}"
-        order: 1
-
-      - id: text-sideboard
-        type: ui-text
-        group: Plugs
-        label: Sideboard Lamp
-        format: "{{msg.payload.state}}"
-        order: 2
-
-      - id: text-bamboo
-        type: ui-text
-        group: Plugs
-        label: Bamboo Lights
-        format: "{{msg.payload.state}}"
-        order: 3
-
-      - id: text-djbooth
-        type: ui-text
-        group: Plugs
-        label: DJ Booth
-        format: "{{msg.payload.state}}"
-        order: 4
-
-      - id: text-couch
-        type: ui-text
-        group: Plugs
-        label: Dual Outlet - Couch
-        format: "{{msg.payload.state_1}} / {{msg.payload.state_2}}"
-        order: 6
-
       - id: permit-btn
         type: ui-button
         group: Plugs
@@ -175,20 +94,12 @@ flows:
         payload:
           value: true
           time: 60
-        order: 5
+        order: 9
 
       - id: mqtt-out
         type: mqtt out
         broker: mosquitto
 
     wires:
-      zigbee-state-squiggle: [text-squiggle]
-      zigbee-state-sideboard: [text-sideboard]
-      zigbee-state-bamboo: [text-bamboo]
-      zigbee-state-djbooth: [text-djbooth]
-      zigbee-state-couch: [text-couch]
       button-in: [single-filter, hold-filter]
-      single-filter: [plug-out-squiggle, plug-out-sideboard, plug-out-bamboo, couch-mapper]
-      couch-mapper: [plug-out-couch]
-      hold-filter: [plug-out-djbooth]
       permit-btn: [mqtt-out]

scripts/flow2json.py

@@ -37,6 +37,117 @@ def make_broker_node(name, cfg):
     return node
 
 
+def build_plugs(flow_def, doc, broker_map, group_map):
+    """Expand a declarative `plugs:` list into state-in/out/widget nodes and wiring.
+
+    Each plug entry: {id, name, channels?}.
+      - single channel: widget shows {{msg.payload.state}}
+      - multi-channel (channels: [1, 2]): a mapper function is emitted before the
+        plug-out so the device toggles per-channel, and the widget shows each state_N.
+
+    single_plugs / hold_plugs are lists of plug ids driven by the function nodes
+    named single_filter / hold_filter respectively.
+    """
+    if "plugs" not in flow_def:
+        return [], {}
+
+    _flow_order["text-order-counter"] = 0
+
+    plug_cfg = {p["id"]: p for p in flow_def["plugs"]}
+
+    def state_keys(p):
+        return [int(k) for k in p.get("channels", [])] if p.get("channels") else []
+
+    nodes = []
+    wires = {}
+
+    def wire(src, target):
+        wires.setdefault(src, []).append(target)
+
+    def channel_mapper_id(pid):
+        return f"mapper-{pid}"
+
+    for key in ("single_plugs", "hold_plugs"):
+        filter_id = flow_def.get("single_filter" if key == "single_plugs" else "hold_filter")
+        if not filter_id:
+            raise ValueError(f"flow missing {'single_filter' if key == 'single_plugs' else 'hold_filter'} for {key}")
+        for pid in flow_def.get(key, []):
+            p = plug_cfg[pid]
+            name = p["name"]
+            keys = state_keys(p)
+
+            sid = f"zigbee-state-{pid}"
+            oid = f"plug-out-{pid}"
+            tid = f"text-{pid}"
+
+            nodes.append({
+                "id": sid, "type": "mqtt in", "wires": [], "name": "",
+                "broker": broker_map[_broker(flow_def, doc)],
+                "topic": f"zigbee2mqtt/{name}", "qos": "0", "datatype": "auto",
+            })
+
+            fmt = "{{msg.payload.state}}"
+            if keys:
+                parts = [f"{{{{msg.payload.state_{k}}}}}" for k in keys]
+                fmt = " / ".join(parts)
+            nodes.append({
+                "id": tid, "type": "ui-text", "wires": [], "name": name,
+                "group": group_map[_group(flow_def)],
+                "width": "6", "height": "2", "order": _order(flow_def),
+                "label": name, "format": fmt, "layout": "row-spread", "className": "",
+            })
+
+            target = oid
+            if keys:
+                mid = channel_mapper_id(pid)
+                code = ", ".join(f"state_{k}: 'TOGGLE'" for k in keys)
+                nodes.append({
+                    "id": mid, "type": "function", "wires": [], "name": "Toggle each outlet",
+                    "func": f"msg.payload = {{{code}}};\nreturn msg;",
+                    "outputs": 1, "noerr": 0, "initialize": "", "finalize": "", "libs": [],
+                })
+                wire(filter_id, mid)
+                wire(mid, oid)
+            else:
+                wire(filter_id, target)
+
+            nodes.append({
+                "id": oid, "type": "mqtt out", "wires": [], "name": "",
+                "broker": broker_map[_broker(flow_def, doc)],
+                "topic": f"zigbee2mqtt/{name}/set", "qos": "2", "retain": False,
+            })
+
+            wire(sid, tid)
+
+    return nodes, wires
+
+
+def _broker(flow_def, doc):
+    # broker used by generated plug nodes: first broker referenced by any node, else first defined
+    for nd in flow_def.get("nodes", []):
+        if nd.get("broker"):
+            return nd["broker"]
+    brokers = list(doc.get("brokers", {}))
+    if not brokers:
+        raise ValueError("no broker defined")
+    return brokers[0]
+
+
+def _group(flow_def):
+    for nd in flow_def.get("nodes", []):
+        if nd.get("group"):
+            return nd["group"]
+    raise ValueError("no dashboard group defined")
+
+
+_flow_order = {"text-order-counter": 0}
+
+
+def _order(flow_def):
+    _flow_order["text-order-counter"] += 1
+    return _flow_order["text-order-counter"]
+
+
 def make_node(nd, col, row, broker_map, group_map):
     ntype = nd["type"]
     nid = nd.get("id", new_id())
@@ -154,6 +265,17 @@ def build_flow(doc, flow_def, node_positions):
         "env": [],
     })
 
+    plug_nodes, plug_wires = build_plugs(flow_def, doc, broker_map, group_map)
+    renum = 0
+    for pn in plug_nodes:
+        pn["z"] = FLOW_ID
+        col = {"mqtt in": 0, "function": 1, "mqtt out": 2, "ui-text": 2}.get(
+            pn.get("type"), 0)
+        pn["x"] = COLUMNS[col]
+        pn["y"] = 80 + (renum * ROW_HEIGHT // 2)
+        renum += 1
+        nodes.append(pn)
+
     for i, nd in enumerate(flow_def["nodes"]):
         col, row = node_positions.get(nd["id"], (0, i))
         node = make_node(nd, col, row, broker_map, group_map)
@@ -163,7 +285,9 @@ def build_flow(doc, flow_def, node_positions):
             node["label"] = nd.get("label", nd.get("name", ""))
         nodes.append(node)
 
-    wires = flow_def.get("wires", {})
+    wires = dict(flow_def.get("wires", {}))
+    for k, v in plug_wires.items():
+        wires.setdefault(k, []).extend(v)
     for src_id, targets in wires.items():
         src = next((n for n in nodes if n["id"] == src_id), None)
         if src: