/// url = 'https://fhir.slade360.co.ke/fhir/StructureMap/ExtractInpatientNursingNote'
/// name = 'ExtractInpatientNursingNote'
/// title = 'Inpatient Nursing Note Extraction'
/// status = 'active'
/// description = 'Turns a response to the inpatient nursing note into a single Composition with one section per heading. A nursing note is a document, so nothing discrete is extracted alongside it; observations recorded at the bedside come from the observation templates, not from here.'

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/Composition" alias Composition as target

group ExtractInpatientNursingNote(source qr : QR, target bundle : Bundle) {
  qr -> bundle.type = 'transaction' "setBundleType";
  qr ->  bundle.entry as entry,  entry.resource = create('Composition') as comp then {
    qr ->  comp,  entry then BuildNoteBase(qr, comp, entry) "noteBase";
    qr -> comp.name = 'InpatientNursingNote' "noteName";
    qr -> comp.title = 'Nursing note' "noteTitle";
    qr -> comp.type as ty then {
      qr -> ty.coding as sghi then {
        qr -> sghi.system = 'https://fhir.slade360.co.ke/fhir/CodeSystem/inpatient-document-type-codesystem' "sghiSystem";
        qr -> sghi.code = 'nursing-note' "sghiCode";
        qr -> sghi.display = 'Nursing note' "sghiDisplay";
      } "sghiCoding";
      qr -> ty.coding as loinc then {
        qr -> loinc.system = 'http://loinc.org' "loincSystem";
        qr -> loinc.code = '34746-8' "loincCode";
        qr -> loinc.display = 'Nurse Note' "loincDisplay";
      } "loincCoding";
      qr -> ty.text = 'Nursing note' "typeText";
    } "noteType";
    qr.item as it where ((linkId = 'observation') and answer.value.exists()) -> comp.section as sec then {
      it -> sec.title = 'Observation' "observationTitle";
      it -> sec then AddSectionText(it, sec) "observationText";
    } "observationRule";
    qr.item as it where ((linkId = 'care') and answer.value.exists()) -> comp.section as sec then {
      it -> sec.title = 'Care given' "careTitle";
      it -> sec then AddSectionText(it, sec) "careText";
    } "careRule";
    qr.item as it where ((linkId = 'concerns') and answer.value.exists()) -> comp.section as sec then {
      it -> sec.title = 'Concerns raised' "concernsTitle";
      it -> sec then AddSectionText(it, sec) "concernsText";
    } "concernsRule";
  } "composition";
}

// ─────────────────────────────────────────────────────────────────────────────
// Shared note scaffolding. Repeated in each note map rather than imported: the
// transform engine resolves `imports` against whatever StructureMaps happen to
// be on the server, and a note that stops extracting because a shared map was
// not uploaded is a worse failure than a duplicated group.
// ─────────────────────────────────────────────────────────────────────────────
// Two notes on what the publisher's StructureMap validator says about this file.
// Source parameters below are left untyped on purpose. Writing `: Element` makes
// the validator compare QuestionnaireResponse.item against the literal 'Element'
// and report them as incompatible with each other, which is noise, not a finding.
// Untyped, it says only that it cannot check the paths.
// `evaluate(context, expression)` is flagged as "takes 1 parameter but 2 were
// found". Leave it. The FML parser in the same jar refuses the one-argument form
// outright -- it wants a parameter, a comma, then the FHIRPath -- so the publisher
// is objecting to what its own compiler emits. Two arguments is the only form that
// compiles, and it is what the R5 transform engine executes.
group BuildNoteBase(source qr : QR, target comp : Composition, target entry) {
  qr -> comp.id = uuid() then SetCompositionFullUrl(comp, entry) "idAndFullUrl";
  qr -> entry.request as request then {
    qr -> request.method = 'POST' "requestMethod";
    qr -> request.url = 'Composition' "requestUrl";
  } "entryRequest";
  qr -> comp.status = 'final' "status";
  qr.subject as s -> comp.subject = s;
  qr.encounter as e -> comp.encounter = e;
  // Composition.date is 1..1. `authored` is only 0..1 on the response, so when a
  // client sends none the extraction time stands in. It is a poor substitute for
  // when the note was written, but a document with no date at all is worse, and
  // extraction happens moments after submission in practice.
  qr.authored as t -> comp.date = t "date";
  qr where (authored.exists().not()) then {
    qr -> comp.date = evaluate(qr, now()) "dateFromExtractionTime";
  } "dateFallback";
  // Composition.author is 1..1 minimum. R5 QuestionnaireResponse carries both
  // `author` (who recorded the answers) and `source` (who supplied them); the
  // author is the one who wrote the note, so it wins, and `source` only stands
  // in when the client did not send an author. If the response carries neither,
  // the note comes out unauthored -- there is nothing on a QuestionnaireResponse
  // to invent one from, and guessing at who wrote a clinical note is not a thing
  // a map should do.
  qr.author as a -> comp.author = a "authorFromAuthor";
  qr where (author.exists().not()) then {
    qr.source as src -> comp.author = src "authorFromSource";
  } "authorFallback";
  // The note is derived from the response, not a copy of it. relatesTo is the
  // only element on R5 Composition that can say so.
  qr -> comp.relatesTo as rel then {
    qr -> rel.type = 'derived-from' "relatesToType";
    qr -> rel.resourceReference = create('Reference') as ref then {
      // `qr.id` already resolves to the type-qualified relative reference under
      // this engine, so it is used unprefixed.
      qr.id as qid -> ref.reference = qid "relatesToRef";
    } "relatesToTarget";
  } "linkQuestionnaireResponse";
}

// The narrative half of a section. The title stays with the caller because a
// group can only be invoked with variables, not string literals.
// Two things here are deliberate. `create('xhtml')` rather than assigning the
// string straight to `div`: the engine hard-casts whatever it is given to
// XhtmlType, so a plain string fails with a ClassCastException. And
// `escape('html')` on the answer: a nurse writing "sats < 92% & falling" would
// otherwise produce a div the server refuses to parse.
group AddSectionText(source it, target sec) {
  it.answer first as a then {
    a.value as v -> sec.text as narrative then {
      v -> narrative.status = 'generated' "narrativeStatus";
      v -> narrative.div = create('xhtml') as xhtml then {
        v -> xhtml.value = evaluate(a, '<div xmlns="http://www.w3.org/1999/xhtml"><p>' + value.toString().escape('html') + '</p></div>') "narrativeDiv";
      } "narrativeXhtml";
    } "sectionText";
  } "sectionAnswer";
}

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