/// url = 'https://fhir.slade360.co.ke/fhir/StructureMap/ExtractInpatientObstetricAdmissionAssessment'
/// name = 'ExtractInpatientObstetricAdmissionAssessment'
/// title = 'Inpatient Obstetric Admission Assessment Extraction'
/// status = 'active'
/// description = 'Four measurements out, four Observations. Gestation, fetal heart rate and cervical dilatation are readings taken at the bedside, so they carry category `exam`; the obstetric history is reported rather than measured, so it carries `social-history`. Every LOINC code here was checked against tx.fhir.org before use.'

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

group ExtractInpatientObstetricAdmissionAssessment(source qr : QR, target bundle : Bundle) {
  qr -> bundle.type = 'transaction' "setBundleType";
  qr.item as itG where ((linkId = 'gestation') and answer.value.exists()) then {
    itG.answer first as aG then {
      aG ->  bundle.entry as entryG,  entryG.resource = create('Observation') as obsG then {
        qr ->  obsG,  entryG then BuildObsBase(qr, obsG, entryG) "gestationBase";
        qr -> obsG then SetExamCategory(qr, obsG) "gestationCategory";
        qr -> obsG.code as code then {
          qr -> code.coding as coding then {
            qr -> coding.system = 'http://loinc.org' "codeSystem";
            qr -> coding.code = '18185-9' "codeCode";
            qr -> coding.display = 'Gestational age' "codeDisplay";
          } "codeCoding";
        } "gestationCode";
        // The item is type `quantity` with a unitOption pinning weeks, so the
        // answer arrives as a Quantity and is copied through whole.
        aG.value as v -> obsG.value = v "gestationValue";
      } "gestationObservation";
    } "gestationAnswer";
  } "gestationRule";
  qr.item as itF where ((linkId = 'fhr') and answer.value.exists()) then {
    itF.answer first as aF then {
      aF ->  bundle.entry as entryF,  entryF.resource = create('Observation') as obsF then {
        qr ->  obsF,  entryF then BuildObsBase(qr, obsF, entryF) "fhrBase";
        qr -> obsF then SetExamCategory(qr, obsF) "fhrCategory";
        qr -> obsF.code as code then {
          qr -> code.coding as coding then {
            qr -> coding.system = 'http://loinc.org' "codeSystem";
            qr -> coding.code = '55283-6' "codeCode";
            qr -> coding.display = 'Fetal Heart rate' "codeDisplay";
          } "codeCoding";
        } "fhrCode";
        aF.value as v -> obsF.value = v "fhrValue";
      } "fhrObservation";
    } "fhrAnswer";
  } "fhrRule";
  qr.item as itD where ((linkId = 'dilatation') and answer.value.exists()) then {
    itD.answer first as aD then {
      aD ->  bundle.entry as entryD,  entryD.resource = create('Observation') as obsD then {
        qr ->  obsD,  entryD then BuildObsBase(qr, obsD, entryD) "dilatationBase";
        qr -> obsD then SetExamCategory(qr, obsD) "dilatationCategory";
        qr -> obsD.code as code then {
          qr -> code.coding as coding then {
            qr -> coding.system = 'http://loinc.org' "codeSystem";
            qr -> coding.code = '11784-6' "codeCode";
            qr -> coding.display = 'Cervical canal external os Diameter palpation' "codeDisplay";
          } "codeCoding";
        } "dilatationCode";
        aD.value as v -> obsD.value = v "dilatationValue";
      } "dilatationObservation";
    } "dilatationAnswer";
  } "dilatationRule";
  qr.item as itH where ((linkId = 'obsHistory') and answer.value.exists()) then {
    itH.answer first as aH then {
      aH ->  bundle.entry as entryH,  entryH.resource = create('Observation') as obsH then {
        qr ->  obsH,  entryH then BuildObsBase(qr, obsH, entryH) "historyBase";
        qr -> obsH then SetSocialHistoryCategory(qr, obsH) "historyCategory";
        qr -> obsH.code as code then {
          qr -> code.coding as coding then {
            qr -> coding.system = 'http://loinc.org' "codeSystem";
            qr -> coding.code = '89213-3' "codeCode";
            qr -> coding.display = 'Obstetrics History and physical note' "codeDisplay";
          } "codeCoding";
        } "historyCode";
        aH.value as v -> obsH.value = v "historyValue";
      } "historyObservation";
    } "historyAnswer";
  } "obsHistoryRule";
}

// ─────────────────────────────────────────────────────────────────────────────
// Shared scaffolding. Repeated in each map rather than imported: the transform
// engine resolves `imports` against whatever StructureMaps happen to be on the
// server, and a form that stops extracting because a shared map was not
// uploaded is a worse failure than a duplicated group.
// ─────────────────────────────────────────────────────────────────────────────
group BuildObsBase(source qr : QR, target obs : Observation, target entry) {
  qr -> obs.id = uuid() then SetObservationFullUrl(obs, entry) "idAndFullUrl";
  qr -> entry.request as request then {
    qr -> request.method = 'POST' "requestMethod";
    qr -> request.url = 'Observation' "requestUrl";
  } "entryRequest";
  qr -> obs.status = 'final' "status";
  qr.subject as s -> obs.subject = s;
  qr.encounter as e -> obs.encounter = e;
  qr.authored as t -> obs.effective = t "effective";
  qr.source as src -> obs.performer = src "performerFromSource";
  qr where (source.exists().not()) then {
    qr.author as a -> obs.performer = a "performerFromAuthor";
  } "performerFallback";
  qr -> obs.derivedFrom = create('Reference') as ref then {
    qr.id as qid -> ref.reference = qid "derivedFromRef";
  } "linkQuestionnaireResponse";
}

group SetExamCategory(source qr : QR, target obs : Observation) {
  qr -> obs.category as cat then {
    qr -> cat.coding as coding then {
      qr -> coding.system = 'http://terminology.hl7.org/CodeSystem/observation-category' "categorySystem";
      qr -> coding.code = 'exam' "categoryCode";
      qr -> coding.display = 'Exam' "categoryDisplay";
    } "categoryCoding";
  } "category";
}

group SetSocialHistoryCategory(source qr : QR, target obs : Observation) {
  qr -> obs.category as cat then {
    qr -> cat.coding as coding then {
      qr -> coding.system = 'http://terminology.hl7.org/CodeSystem/observation-category' "categorySystem";
      qr -> coding.code = 'social-history' "categoryCode";
      qr -> coding.display = 'Social History' "categoryDisplay";
    } "categoryCoding";
  } "category";
}

group SetObservationFullUrl(source obs : Observation, target entry) {
  obs.id as id -> entry.fullUrl = append('https://fhir.slade360.co.ke/fhir/Observation/', id) "assignFullUrl";
}