map "https://fhir.hl7.at/prenudge/appdata/r4/StructureMap/StepCountQuestionnaireResponseToObservation" = "StepCountQuestionnaireResponseToObservation"

// Step Count Q to O

uses "http://hl7.org/fhir/StructureDefinition/QuestionnaireResponse" alias QR as source
uses "http://hl7.org/fhir/StructureDefinition/Observation" alias Obs as target
uses "http://hl7.org/fhir/StructureDefinition/Quantity" alias Quantity as source

imports "http://hl7.org/fhir/StructureMap/*"
imports "https://fhir.hl7.at/prenudge/appdata/r4/StructureMap/QuestionnaireResponseToObservationBase"

group StepCountQuestionnaireResponseToObservation(source src : QR, target tgt : Obs) {
  src then SetObservationBase(src, tgt) "Base";
  src ->  tgt.meta = create('Meta') as meta,  meta.profile = 'https://fhir.hl7.at/prenudge/appdata/r4/StructureDefinition/at-prenudge-stepcount-observation' "SetProfile";
  src -> tgt.code = cc('http://loinc.org', '41950-7', 'Number of steps in 24 hour Measured') "SetCode";
  src.item as item where linkId = 'step-count-today' then MapStepCount(item, tgt) "ProcessItem";
}

group MapStepCount(source src : QR, target tgt : Obs) {
  src.answer as answer then {
    answer.valueQuantity as srcQty then MapStepCountQuantity(srcQty, tgt) "MapValueQuantity";
  } "ProcessAnswer";
}

group MapStepCountQuantity(source srcQty : Quantity, target tgt : Obs) {
  srcQty.value as v -> tgt.value = create('Quantity') as qty then {
    v.value as numVal -> qty.value = numVal "SetValue";
    srcQty -> qty.unit = '{steps}/d' "SetUnit";
    srcQty -> qty.system = 'http://unitsofmeasure.org' "SetSystem";
    srcQty -> qty.code = '{steps}/d' "SetCode";
  } "MapQuantityValue";
}