{
  "version": 1,
  "title": "Tutorial — Calculated and Hidden Fields",
  "fields": [
    {
      "id": "intro",
      "type": "note",
      "label": "Calculated fields are computed automatically from other field values using arithmetic expressions. Hidden fields store a fixed value (like a survey round or version number) that is included in every submission without being shown to the field worker."
    },
    {
      "id": "divider_1",
      "type": "divider"
    },
    {
      "id": "calculated_note",
      "type": "note",
      "label": "Calculated fields: the expression uses field IDs and arithmetic operators (+, -, *, /). The result is included in the submission automatically. The field worker never sees it."
    },
    {
      "id": "adults_male",
      "type": "number",
      "label": "Adult males (18+)"
    },
    {
      "id": "adults_female",
      "type": "number",
      "label": "Adult females (18+)"
    },
    {
      "id": "children_count",
      "type": "number",
      "label": "Children (under 18)"
    },
    {
      "id": "total_members",
      "type": "calculated",
      "label": "Total household members (auto)",
      "expression": "adults_male + adults_female + children_count"
    },
    {
      "id": "divider_2",
      "type": "divider"
    },
    {
      "id": "income_note",
      "type": "note",
      "label": "Another example: calculate a per-capita income from two inputs."
    },
    {
      "id": "monthly_income",
      "type": "number",
      "label": "Monthly household income (USD)"
    },
    {
      "id": "income_per_capita",
      "type": "calculated",
      "label": "Monthly income per capita (auto)",
      "expression": "monthly_income / total_members"
    },
    {
      "id": "divider_3",
      "type": "divider"
    },
    {
      "id": "hidden_note",
      "type": "note",
      "label": "Hidden fields: always included in the submission with a fixed value. Useful for tagging submissions with a survey round, form version, or project code. The field worker never sees or fills it."
    },
    {
      "id": "survey_round",
      "type": "hidden",
      "label": "Survey Round",
      "default": "2026-Q1"
    },
    {
      "id": "form_version",
      "type": "hidden",
      "label": "Form Version",
      "default": "1.0"
    },
    {
      "id": "project_code",
      "type": "hidden",
      "label": "Project Code",
      "default": "PROJ-001"
    },
    {
      "id": "divider_4",
      "type": "divider"
    },
    {
      "id": "location",
      "type": "geopoint",
      "label": "Location",
      "required": true
    },
    {
      "id": "notes",
      "type": "textarea",
      "label": "Notes"
    }
  ]
}