Conditional logic

"logic": { "action": "show", "match": "all", "conditions": [{ "field": "attended", "operator": "equals", "value": "yes" }] }

action is one of show, hide, disable (can't be edited while the rule matches), enable (can only be edited while it matches) and require (becomes required while it matches). Give logic a list of rules to combine several (every show/hide rule has to allow it). match is all (AND), any (OR) or none (NOT any). A condition can be a group with its own match and conditions, nested as deep as needed: (A or B) and (C and D) is { "match": "all", "conditions": [ { "match": "any", "conditions": [A, B] }, { "match": "all", "conditions": [C, D] } ] }. Empty groups are ignored. Operators: equals not_equals contains not_contains gt lt empty not_empty. field is another field's model. For lists (checkbox groups, repeaters) gt / lt compare the number of entries, so { "field": "guests", "operator": "lt", "value": 1 } means "no guest added". Hidden fields are not validated and not submitted; fields switched off by a rule are not validated.

Months, weeks and years. { "type": "month" } answers "2026-10", { "type": "week" } an ISO week "2026-W42" (picked as a calendar row, with week numbers), { "type": "year" } "2026". config.multiple: true answers a list; config.minDate / maxDate ("today", "+60" or a date) grey out what is outside.