feat: one action

lib/data/yaml_codec.dart

@@ -657,6 +657,9 @@ Action? _parseAction(YamlMap m) {
   if (m.containsKey('sleep')) {
     return SleepAction(milliseconds: m['sleep'] as int? ?? 0);
   }
+  if (m.containsKey('one')) {
+    return OneAction(cases: _parseActions(m['one']));
+  }
   if (m.containsKey('function')) {
     return FunctionAction(expression: m['function'].toString());
   }

lib/data/yaml_io.dart

@@ -468,6 +468,9 @@ Map<String, dynamic> actionToMap(Action action) => switch (action) {
   },
   SleepAction(:final milliseconds) => {'sleep': milliseconds},
   FunctionAction(:final expression) => {'function': expression},
+  OneAction(:final cases) => {
+    'one': cases.map(triggerActionToMap).toList(),
+  },
   RawAction(:final raw) => {'__raw': raw},
 };
 

lib/domain/edit/schema/edit_schema.dart

@@ -57,6 +57,70 @@ final TreeNode<SwipeMode> swipeModeNode = subtree<SwipeMode>(
   ],
 );
 
+// Non-recursive TriggerAction subtree used for the cases inside a `one:`
+// branch. Mirrors [actionNode] but excludes the OneAction case, which both
+// avoids schema recursion and enforces the one-level nesting cap (no branch
+// inside a branch). The `branchCase` scope on the list keeps the generated lens
+// names distinct from the top-level `action*` family.
+final TreeNode<TriggerAction> branchCaseNode = subtree<TriggerAction>(
+  fields: [
+    sealed(
+      TriggerActionMeta.action,
+      cases: [
+        valueCase<CommandAction>(
+          'command',
+          fields: [
+            prop(CommandActionMeta.command),
+            prop(
+              CommandActionMeta.wait,
+              compare: projected<CommandAction, bool?>((v) => v?.effectiveWait),
+            ),
+          ],
+        ),
+        valueCase<PlasmaShortcutAction>(
+          'plasma',
+          fields: [
+            prop(PlasmaShortcutActionMeta.component),
+            prop(PlasmaShortcutActionMeta.shortcut),
+          ],
+        ),
+        valueCase<ActivateWindowAction>(
+          'activateWindow',
+          fields: [prop(ActivateWindowActionMeta.windowId)],
+        ),
+        valueCase<ReplaceTextAction>(
+          'replaceText',
+          fields: [prop(ReplaceTextActionMeta.rules)],
+        ),
+        valueCase<SleepAction>(
+          'sleep',
+          fields: [prop('duration', property: SleepActionMeta.milliseconds)],
+        ),
+        valueCase<FunctionAction>(
+          'function',
+          fields: [prop(FunctionActionMeta.expression)],
+        ),
+        valueCase<RawAction>('raw', fields: [prop(RawActionMeta.raw)]),
+        valueCase<InputAction>(
+          'input',
+          fields: [prop('inputEntries', property: InputActionMeta.entries)],
+        ),
+      ],
+    ),
+    prop('triggerOn', property: TriggerActionMeta.on),
+    prop(TriggerActionMeta.interval, adapter: nullableText()),
+    prop(TriggerActionMeta.threshold, adapter: nullableText()),
+    prop(TriggerActionMeta.limit, adapter: nullableInt()),
+    prop(
+      TriggerActionMeta.enabled,
+      compare: projected<TriggerAction, bool?>((v) => v?.effectiveEnabled),
+    ),
+    prop(TriggerActionMeta.conflicting),
+    prop(TriggerActionMeta.conditions),
+    prop(TriggerActionMeta.id, adapter: nullableText()),
+  ],
+);
+
 final TreeNode<TriggerAction> actionNode = subtree<TriggerAction>(
   fields: [
     sealed(
@@ -98,6 +162,19 @@ final TreeNode<TriggerAction> actionNode = subtree<TriggerAction>(
           fields: [prop(FunctionActionMeta.expression)],
         ),
         valueCase<RawAction>('raw', fields: [prop(RawActionMeta.raw)]),
+        valueCase<OneAction>(
+          'one',
+          fields: [
+            list(
+              OneActionMeta.cases,
+              of: branchCaseNode,
+              scope: 'branchCase',
+              location: 'BranchCaseLocation',
+              parentField: 'action',
+              indexField: 'caseIndex',
+            ),
+          ],
+        ),
         valueCase<InputAction>(
           'input',
           fields: [prop('inputEntries', property: InputActionMeta.entries)],

lib/domain/edit/schema/edit_schema_extra.dart

@@ -139,6 +139,41 @@ final _gestureActionsPart = LensPart<Gesture, List<TriggerAction>>(
 Lens<List<TriggerAction>> gestureActionsLens(GestureLocation location) =>
     gestureLens(location).then(_gestureActionsPart);
 
+/// Whole-list lens for the cases of a `one:` ([OneAction]) branch at
+/// [location]. Reads `[]` when the addressed action isn't a [OneAction] or the
+/// index is out of range; writes by replacing that action with a new
+/// [OneAction] carrying the given cases (a no-op when the target isn't a
+/// branch). Mirrors [gestureActionsLens] for the nested case list — the
+/// per-case field lenses (`branchCase*Lens`) are generated.
+Lens<List<TriggerAction>> branchCasesLens(
+  ActionLocation location,
+) => Lens<List<TriggerAction>>(
+  get: (config) {
+    final actions = gestureActionsLens(location.gesture).get(config);
+    if (location.actionIndex < 0 || location.actionIndex >= actions.length) {
+      return const [];
+    }
+    final action = actions[location.actionIndex].action;
+    return action is OneAction ? action.cases : const [];
+  },
+  set: (config, cases) {
+    final actions = gestureActionsLens(location.gesture).get(config);
+    if (location.actionIndex < 0 || location.actionIndex >= actions.length) {
+      return config;
+    }
+    final current = actions[location.actionIndex];
+    if (current.action is! OneAction) return config;
+    final next = List<TriggerAction>.of(actions);
+    next[location.actionIndex] = current.copyWith(
+      action: OneAction(cases: cases),
+    );
+    return gestureActionsLens(location.gesture).set(config, next);
+  },
+  name:
+      'gesture[${location.gesture}].action'
+      '[${location.actionIndex}].cases',
+);
+
 Lens<DeviceRuleProperties> defaultDevicePropertiesLens(DeviceType device) =>
     Lens<DeviceRuleProperties>(
       get: (config) =>
@@ -343,3 +378,16 @@ TriggerAction? actionAt(Config? config, ActionLocation location) {
   }
   return common.actions[location.actionIndex];
 }
+
+/// The [TriggerAction] for a single case of a `one:` branch, or null when the
+/// addressed action isn't a [OneAction] or any index is out of range.
+TriggerAction? branchCaseAt(Config? config, BranchCaseLocation location) {
+  if (config == null) return null;
+  final parent = ActionLocation(
+    gesture: location.action,
+    actionIndex: location.actionIndex,
+  );
+  final cases = branchCasesLens(parent).get(config);
+  if (location.caseIndex < 0 || location.caseIndex >= cases.length) return null;
+  return cases[location.caseIndex];
+}

lib/l10n/app_en.arb

@@ -295,6 +295,16 @@
   "actionMetaFunctionSubtitle": "Run a JavaScript function",
   "actionMetaRawLabel": "Raw YAML",
   "actionMetaRawSubtitle": "Hand-authored unsupported action config",
+  "actionMetaOneLabel": "First match",
+  "actionMetaOneSubtitle": "Run one action depending on conditions",
+  "actionMetaOneSummary": "{count, plural, =0{no cases} =1{1 case} other{{count} cases}}",
+  "@actionMetaOneSummary": {
+    "placeholders": {
+      "count": {
+        "type": "int"
+      }
+    }
+  },
   "actionSummaryNoCommand": "No command",
   "actionSummaryNotConfigured": "Not configured",
   "actionSummaryEmpty": "Empty",
@@ -657,6 +667,31 @@
   "dialogUnsavedChangesBody": "You have unsaved changes. Apply them or discard before leaving.",
   "actionApply": "Apply",
   "addAction": "Add Action",
+  "branchHeader_firstMatch": "First match",
+  "branchHeader_switchOn": "Switch on",
+  "branchHeader_caseCount": "{count, plural, =0{No cases yet} =1{1 case} other{{count} cases}}",
+  "@branchHeader_caseCount": {
+    "placeholders": {
+      "count": {
+        "type": "int"
+      }
+    }
+  },
+  "branchAddCase": "Add case",
+  "branchAddDefault": "Add default",
+  "branchCase_anyValue": "any value",
+  "branchCase_deadWarning": "Never runs: a default above always matches",
+  "branchCase_conditionTitle": "Runs when",
+  "branchAddCaseFor": "Add {discriminator}",
+  "@branchAddCaseFor": {
+    "placeholders": {
+      "discriminator": {
+        "type": "String"
+      }
+    }
+  },
+  "branchCase_when": "when",
+  "branchCase_otherwise": "otherwise",
   "dialogAddActionTitle": "Add action",
   "actionIntervalHint": "+, -, or number",
   "actionLimitHint": "0 = unlimited",

lib/l10n/app_localizations.dart

@@ -1480,6 +1480,24 @@ abstract class AppLocalizations {
   /// **'Hand-authored unsupported action config'**
   String get actionMetaRawSubtitle;
 
+  /// No description provided for @actionMetaOneLabel.
+  ///
+  /// In en, this message translates to:
+  /// **'First match'**
+  String get actionMetaOneLabel;
+
+  /// No description provided for @actionMetaOneSubtitle.
+  ///
+  /// In en, this message translates to:
+  /// **'Run one action depending on conditions'**
+  String get actionMetaOneSubtitle;
+
+  /// No description provided for @actionMetaOneSummary.
+  ///
+  /// In en, this message translates to:
+  /// **'{count, plural, =0{no cases} =1{1 case} other{{count} cases}}'**
+  String actionMetaOneSummary(int count);
+
   /// No description provided for @actionSummaryNoCommand.
   ///
   /// In en, this message translates to:
@@ -3382,6 +3400,72 @@ abstract class AppLocalizations {
   /// **'Add Action'**
   String get addAction;
 
+  /// No description provided for @branchHeader_firstMatch.
+  ///
+  /// In en, this message translates to:
+  /// **'First match'**
+  String get branchHeader_firstMatch;
+
+  /// No description provided for @branchHeader_switchOn.
+  ///
+  /// In en, this message translates to:
+  /// **'Switch on'**
+  String get branchHeader_switchOn;
+
+  /// No description provided for @branchHeader_caseCount.
+  ///
+  /// In en, this message translates to:
+  /// **'{count, plural, =0{No cases yet} =1{1 case} other{{count} cases}}'**
+  String branchHeader_caseCount(int count);
+
+  /// No description provided for @branchAddCase.
+  ///
+  /// In en, this message translates to:
+  /// **'Add case'**
+  String get branchAddCase;
+
+  /// No description provided for @branchAddDefault.
+  ///
+  /// In en, this message translates to:
+  /// **'Add default'**
+  String get branchAddDefault;
+
+  /// No description provided for @branchCase_anyValue.
+  ///
+  /// In en, this message translates to:
+  /// **'any value'**
+  String get branchCase_anyValue;
+
+  /// No description provided for @branchCase_deadWarning.
+  ///
+  /// In en, this message translates to:
+  /// **'Never runs: a default above always matches'**
+  String get branchCase_deadWarning;
+
+  /// No description provided for @branchCase_conditionTitle.
+  ///
+  /// In en, this message translates to:
+  /// **'Runs when'**
+  String get branchCase_conditionTitle;
+
+  /// No description provided for @branchAddCaseFor.
+  ///
+  /// In en, this message translates to:
+  /// **'Add {discriminator}'**
+  String branchAddCaseFor(String discriminator);
+
+  /// No description provided for @branchCase_when.
+  ///
+  /// In en, this message translates to:
+  /// **'when'**
+  String get branchCase_when;
+
+  /// No description provided for @branchCase_otherwise.
+  ///
+  /// In en, this message translates to:
+  /// **'otherwise'**
+  String get branchCase_otherwise;
+
   /// No description provided for @dialogAddActionTitle.
   ///
   /// In en, this message translates to:

lib/l10n/app_localizations_en.dart

@@ -744,6 +744,24 @@ class AppLocalizationsEn extends AppLocalizations {
   @override
   String get actionMetaRawSubtitle => 'Hand-authored unsupported action config';
 
+  @override
+  String get actionMetaOneLabel => 'First match';
+
+  @override
+  String get actionMetaOneSubtitle => 'Run one action depending on conditions';
+
+  @override
+  String actionMetaOneSummary(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count cases',
+      one: '1 case',
+      zero: 'no cases',
+    );
+    return '$_temp0';
+  }
+
   @override
   String get actionSummaryNoCommand => 'No command';
 
@@ -1881,6 +1899,51 @@ class AppLocalizationsEn extends AppLocalizations {
   @override
   String get addAction => 'Add Action';
 
+  @override
+  String get branchHeader_firstMatch => 'First match';
+
+  @override
+  String get branchHeader_switchOn => 'Switch on';
+
+  @override
+  String branchHeader_caseCount(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count cases',
+      one: '1 case',
+      zero: 'No cases yet',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get branchAddCase => 'Add case';
+
+  @override
+  String get branchAddDefault => 'Add default';
+
+  @override
+  String get branchCase_anyValue => 'any value';
+
+  @override
+  String get branchCase_deadWarning =>
+      'Never runs: a default above always matches';
+
+  @override
+  String get branchCase_conditionTitle => 'Runs when';
+
+  @override
+  String branchAddCaseFor(String discriminator) {
+    return 'Add $discriminator';
+  }
+
+  @override
+  String get branchCase_when => 'when';
+
+  @override
+  String get branchCase_otherwise => 'otherwise';
+
   @override
   String get dialogAddActionTitle => 'Add action';