{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "$id": "https://formhaus.dev/schema/form-definition.json",
  "title": "Formhaus form definition",
  "type": "object",
  "properties": {
    "$schema": {
      "type": "string"
    },
    "id": {
      "type": "string",
      "description": "Unique form identifier."
    },
    "title": {
      "type": "string",
      "description": "Form title for host UI and Figma output. Renderers do not display it."
    },
    "submit": {
      "$ref": "#/definitions/FormAction",
      "description": "Submit button on the last step."
    },
    "cancel": {
      "$ref": "#/definitions/FormAction",
      "description": "Optional cancel button."
    },
    "fields": {
      "type": "array",
      "items": {
        "$ref": "#/definitions/FormField"
      },
      "description": "Fields of a single-step form."
    },
    "steps": {
      "type": "array",
      "items": {
        "$ref": "#/definitions/FormStep"
      },
      "description": "Steps of a multi-step form. FormEngine rejects a definition with both non-empty fields and steps."
    }
  },
  "required": [
    "id",
    "title",
    "submit"
  ],
  "additionalProperties": false,
  "description": "A Formhaus form. Use fields for a single-step form or steps for a multi-step form, not both.",
  "definitions": {
    "FormAction": {
      "type": "object",
      "properties": {
        "label": {
          "type": "string"
        },
        "variant": {
          "type": "string",
          "enum": [
            "primary",
            "secondary",
            "text"
          ]
        },
        "action": {
          "type": "string"
        },
        "disabled": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/ShowCondition"
          }
        }
      },
      "required": [
        "label"
      ],
      "additionalProperties": false
    },
    "ShowCondition": {
      "type": "object",
      "properties": {
        "field": {
          "type": "string",
          "description": "Key of the field to check."
        },
        "eq": {
          "type": [
            "string",
            "number",
            "boolean"
          ],
          "description": "Matches when the value strictly equals this."
        },
        "neq": {
          "type": [
            "string",
            "number",
            "boolean"
          ],
          "description": "Matches when the value does not strictly equal this."
        },
        "in": {
          "type": "array",
          "items": {
            "type": [
              "string",
              "number"
            ]
          },
          "description": "Matches when the value is one of these."
        },
        "notIn": {
          "type": "array",
          "items": {
            "type": [
              "string",
              "number"
            ]
          },
          "description": "Matches when the value is none of these."
        },
        "notEmpty": {
          "type": "boolean",
          "description": "Matches when the value is not undefined, null, an empty string or an empty array."
        }
      },
      "required": [
        "field"
      ],
      "additionalProperties": false,
      "description": "A condition on another field value. Use one operator per condition; only the first of eq, neq, in, notIn, notEmpty applies."
    },
    "FormField": {
      "type": "object",
      "properties": {
        "key": {
          "type": "string",
          "description": "Key of the field value in the submitted values. Unique within the form."
        },
        "type": {
          "$ref": "#/definitions/FieldType",
          "description": "Field type. A built-in type or a custom type rendered through the renderer components prop."
        },
        "label": {
          "type": "string",
          "description": "Label text."
        },
        "placeholder": {
          "type": "string"
        },
        "helperText": {
          "type": "string",
          "description": "Hint text below the field."
        },
        "autoAdvance": {
          "type": "boolean",
          "description": "Moves to the next step when the field is committed: a built-in radio on click, Space or Enter, or a custom field calling onCommit. The last step never auto-submits."
        },
        "defaultValue": {
          "description": "Initial value. Also the value restored on reset or skip."
        },
        "show": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/ShowCondition"
          },
          "description": "Field is visible only when all conditions match. Hidden fields are cleared, not validated and not submitted."
        },
        "showAny": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/ShowCondition"
          },
          "description": "Field is visible when any condition matches."
        },
        "validation": {
          "$ref": "#/definitions/FieldValidation",
          "description": "Validation rules checked on Continue and on submit, not on blur."
        },
        "options": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/FieldOption"
          },
          "description": "Static options for select, autocomplete, multiselect and radio fields."
        },
        "optionsFrom": {
          "type": "string",
          "description": "Key of an options provider passed to the renderer, used instead of static options."
        },
        "optionsDependsOn": {
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "accept": {
          "type": "string"
        },
        "rows": {
          "type": "number"
        },
        "mask": {
          "type": "string"
        },
        "inputMode": {
          "type": "string",
          "enum": [
            "text",
            "numeric",
            "tel",
            "email"
          ]
        }
      },
      "required": [
        "key",
        "type",
        "label"
      ],
      "additionalProperties": false
    },
    "FieldType": {
      "anyOf": [
        {
          "$ref": "#/definitions/DefaultFieldType"
        },
        {
          "type": "string"
        }
      ]
    },
    "DefaultFieldType": {
      "type": "string",
      "enum": [
        "text",
        "email",
        "phone",
        "number",
        "password",
        "select",
        "autocomplete",
        "multiselect",
        "checkbox",
        "radio",
        "switch",
        "file",
        "date",
        "datetime",
        "textarea"
      ]
    },
    "FieldValidation": {
      "type": "object",
      "properties": {
        "required": {
          "type": [
            "boolean",
            "string"
          ]
        },
        "minLength": {
          "type": "number"
        },
        "minLengthMessage": {
          "type": "string"
        },
        "maxLength": {
          "type": "number"
        },
        "maxLengthMessage": {
          "type": "string"
        },
        "min": {
          "type": "number"
        },
        "minMessage": {
          "type": "string"
        },
        "max": {
          "type": "number"
        },
        "maxMessage": {
          "type": "string"
        },
        "pattern": {
          "type": "string"
        },
        "patternMessage": {
          "type": "string"
        },
        "matchField": {
          "type": "string",
          "description": "Key of another field whose value this field must equal."
        },
        "matchFieldMessage": {
          "type": "string"
        },
        "validator": {
          "type": "string"
        }
      },
      "additionalProperties": false
    },
    "FieldOption": {
      "type": "object",
      "properties": {
        "value": {
          "type": "string"
        },
        "label": {
          "type": "string"
        }
      },
      "required": [
        "value",
        "label"
      ],
      "additionalProperties": false
    },
    "FormStep": {
      "type": "object",
      "properties": {
        "routes": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/StepRoute"
          },
          "description": "Forward destinations checked in order. The first match with a visible target wins. With no match, navigation continues to the next visible step."
        },
        "id": {
          "type": "string",
          "description": "Unique step identifier, used as a route target. FormEngine rejects duplicates."
        },
        "title": {
          "type": "string"
        },
        "description": {
          "type": "string"
        },
        "fields": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/FormField"
          }
        },
        "show": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/ShowCondition"
          },
          "description": "Step is visible only when all conditions match. Hidden steps are skipped and not submitted."
        },
        "showAny": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/ShowCondition"
          },
          "description": "Step is visible when any condition matches."
        },
        "next": {
          "anyOf": [
            {
              "$ref": "#/definitions/FormAction"
            },
            {
              "type": "boolean",
              "const": false
            }
          ],
          "description": "Overrides the Continue button. false hides it."
        },
        "back": {
          "anyOf": [
            {
              "$ref": "#/definitions/FormAction"
            },
            {
              "type": "boolean",
              "const": false
            }
          ],
          "description": "Overrides the Back button. false hides it."
        },
        "skip": {
          "$ref": "#/definitions/FormAction",
          "description": "Shows a Skip button that resets the step fields and moves forward without validation."
        }
      },
      "required": [
        "id",
        "title",
        "fields"
      ],
      "additionalProperties": false
    },
    "StepRoute": {
      "type": "object",
      "properties": {
        "to": {
          "type": [
            "string",
            "null"
          ],
          "description": "Id of a later step. null makes the current step the last one on this path."
        },
        "show": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/ShowCondition"
          },
          "description": "Route matches only when all conditions match. Without show or showAny the route always matches."
        },
        "showAny": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/ShowCondition"
          },
          "description": "Route matches when any condition matches."
        }
      },
      "required": [
        "to"
      ],
      "additionalProperties": false,
      "description": "A forward destination for a step."
    }
  }
}