Conditional logic

Phase 7 evaluates the same show/hide and action rules on the server (ConditionEngine) and in the browser (assets/frontend/js/form.js).

Disabled or empty groups are always true: the field stays visible and the action runs.

Group shape

Field and action conditions is an object, not a list:

{
  "enabled": false,
  "effect": "show",
  "logic": "all",
  "rules": [
    {
      "id": "rule_a1b2c3d4",
      "field": "kind",
      "operator": "is",
      "value": "business"
    }
  ]
}

• effect: show | hide — fields only. Actions ignore effect; matches() means “run this action”.
• logic: all | any
• Rule IDs are stable (rule_ + 8 hex)
• A legacy list of {field, operator, value} rules is normalized to an enabled show / all group

Operators

ID	Needs value
is	yes
is_not	yes
contains	yes
not_contains	yes
starts_with	yes
ends_with	yes
is_empty	no
is_not_empty	no
greater_than	yes
less_than	yes

String compares are case-insensitive. greater_than / less_than require numeric values. Unknown operators never match. Add-ons can append catalogue entries with ad_form_condition_operators.

Evaluation

1. Fields are walked in definition order.
2. Rules whose field equals the current field key are skipped (no self-reference).
3. Hidden fields count as empty for later rules (cascade).
4. Submit fields are always visible.
5. Hidden fields skip required validation and are omitted from the stored payload and submission_meta.
6. ActionRunner skips an action when matches() is false (debug log, not a failure).

Frontend

Enabled groups are serialized on the wrap as data-conditions. Required fields keep data-required="1" even when hidden so JS can restore required after they become visible.

Hidden wraps get class is-conditionally-hidden and the hidden attribute. Controls are disabled so classic POST drops them. AJAX collectValues(form, true) skips hidden wraps.

PHP

• Dingfelder\AdForm\Conditions\ConditionEngineInterface
• Dingfelder\AdForm\Conditions\ConditionEngine
• Dingfelder\AdForm\REST\ConditionsController

SubmitService, ActionRunner and FormRenderer take an optional ConditionEngineInterface (constructor signatures stay compatible). The container injects the engine.

REST catalogue: GET /wp-json/ad-form/v1/conditions (capability edit_ad_form_forms).