define "SDE Sex":
  case
      when Patient.gender = 'male' then Code { code: 'M', system: 'http://hl7.org/fhir/v3/AdministrativeGender', display: 'Male' }
      when Patient.gender = 'female' then Code { code: 'F', system: 'http://hl7.org/fhir/v3/AdministrativeGender', display: 'Female' }
      else null
    end

define "SDE Sex":
  SDE."SDE Sex"

define "Non Elective Inpatient Encounter":
  ["Encounter": "Nonelective Inpatient Encounter"] NonElectiveEncounter
        where NonElectiveEncounter.period ends during day of "Measurement Period"

define "All Stroke Encounter":
  "Non Elective Inpatient Encounter" NonElectiveEncounter
  let ConditionCode: NonElectiveEncounter.principalDiagnosis().code
    where ( ConditionCode in "Hemorrhagic Stroke"
       or   ConditionCode in "Ischemic Stroke" )

define "Encounter with Principal Diagnosis and Age":
  "All Stroke Encounter" AllStrokeEncounter
    where AgeInYearsAt(date from start of AllStrokeEncounter.period ) >= 18

define "Ischemic Stroke Encounter":
  "Encounter with Principal Diagnosis and Age" EncounterWithAge
    where EncounterWithAge.principalDiagnosis().code in "Ischemic Stroke"

define "Numerator":
  TJC."Ischemic Stroke Encounter" IschemicStrokeEncounter
    with ["MedicationRequest": "Antithrombotic Therapy for Ischemic Stroke"] DischargeAntithrombotic
      such that DischargeAntithrombotic.authoredOn during IschemicStrokeEncounter.period

define "Denominator":
  TJC."Ischemic Stroke Encounter"

define "SDE Payer":
  [Coverage: type in "Payer Type"] Payer
    return {
      code: Payer.type,
      period: Payer.period
    }

define "SDE Payer":
  SDE."SDE Payer"

define "Initial Population":
  TJC."Encounter with Principal Diagnosis and Age"

define "SDE Ethnicity":
  Patient.ethnicity E
    return Tuple {
      codes: { E.ombCategory } union E.detailed,
      display: E.text
    }

define "SDE Ethnicity":
  SDE."SDE Ethnicity"

define "Ischemic Stroke Encounters with Discharge Disposition":
  "Ischemic Stroke Encounter" IschemicStrokeEncounter
  let DischDisp: IschemicStrokeEncounter.hospitalization.dischargeDisposition
  	where  DischDisp in "Discharge To Acute Care Facility"
		or DischDisp in "Left Against Medical Advice"
		or DischDisp in "Patient Expired"
		or DischDisp in "Discharged to Home for Hospice Care"
		or DischDisp in "Discharged to Health Care Facility for Hospice Care"

define "Intervention Comfort Measures":
  ( ["ServiceRequest": code in "Comfort Measures"] SR
    where SR.status in { 'active', 'completed', 'on-hold' }
      and SR.intent in { 'order', 'original-order', 'reflex-order', 'filler-order', 'instance-order' }
      and SR.doNotPerform is not true
  )  
  union ( ["Procedure": "Comfort Measures"] InterventionPerformed
        where InterventionPerformed.status in { 'completed', 'in-progress' }
  )

define "Encounter with Comfort Measures during Hospitalization for Patients with Documented Ischemic Stroke":
  "Denominator" Encounter
    with TJC."Intervention Comfort Measures" ComfortMeasure
      such that Coalesce(start of ComfortMeasure.performed.toInterval(), ComfortMeasure.authoredOn) during Encounter.hospitalizationWithObservation ( )

define "Denominator Exclusions":
  TJC."Ischemic Stroke Encounters with Discharge Disposition"
    union "Encounter with Comfort Measures during Hospitalization for Patients with Documented Ischemic Stroke"

define "SDE Race":
  Patient.race R
    return Tuple {
      codes: R.ombCategory union R.detailed,
      display: R.text
    }

define "SDE Race":
  SDE."SDE Race"

define "Reason for Not Giving Antithrombotic at Discharge":
  ["MedicationNotRequested": "Antithrombotic Therapy for Ischemic Stroke"] NoAntithromboticDischarge
    where ( NoAntithromboticDischarge.reasonCode in "Medical Reason For Not Providing Treatment"
        or NoAntithromboticDischarge.reasonCode in "Patient Refusal"
    )
      and ( NoAntithromboticDischarge.isCommunity ( )
          or NoAntithromboticDischarge.isDischarge ( )
      )
      and NoAntithromboticDischarge.intent in { 'order', 'original-order', 'reflex-order', 'filler-order', 'instance-order' }

define "Encounter with Documented Reason for No Antithrombotic At Discharge":
  TJC."Ischemic Stroke Encounter" IschemicStrokeEncounter
    with "Reason for Not Giving Antithrombotic at Discharge" NoDischargeAntithrombotic
      such that NoDischargeAntithrombotic.authoredOn during IschemicStrokeEncounter.period

define "Pharmacological Contraindications for Antithrombotic Therapy at Discharge":
  ["MedicationRequest": "Pharmacological Contraindications For Antithrombotic Therapy"] Pharmacological
    where ( Pharmacological.isCommunity ( )
        or Pharmacological.isDischarge ( )
    )
      and Pharmacological.status in { 'active', 'completed' }
      and Pharmacological.intent in { 'order', 'original-order', 'reflex-order', 'filler-order', 'instance-order' }
      and Pharmacological.doNotPerform is not true

define "Encounter with Pharmacological Contraindications for Antithrombotic Therapy at Discharge":
  TJC."Ischemic Stroke Encounter" IschemicStrokeEncounter
    with "Pharmacological Contraindications for Antithrombotic Therapy at Discharge" DischargePharmacological
      such that DischargePharmacological.authoredOn during IschemicStrokeEncounter.period

define "Denominator Exceptions":
  "Encounter with Documented Reason for No Antithrombotic At Discharge"
    union "Encounter with Pharmacological Contraindications for Antithrombotic Therapy at Discharge"

/*
@description: Returns the condition that is specified as the principal diagnosis for the encounter
*/
define fluent function principalDiagnosis(Encounter Encounter ):
	singleton from ((Encounter.diagnosis D where D.rank = 1) PD
      return singleton from ([Condition] C where C.id = PD.condition.reference.getId())
	)

/*
@description: Returns the tail of the given uri (i.e. everything after the last slash in the URI).
@comment: This function can be used to determine the logical id of a given resource. It can be used in
a single-server environment to trace references. However, this function does not attempt to resolve
or distinguish the base of the given url, and so cannot be used safely in multi-server environments.
*/
define fluent function getId(uri String):
  Last(Split(uri, '/'))

define function ToString(value uri): value.value

define function ToCode(coding FHIR.Coding):
    if coding is null then
        null
    else
        System.Code {
          code: coding.code.value,
          system: coding.system.value,
          version: coding.version.value,
          display: coding.display.value
        }

/*
@description: Hospitalization with Observation returns the total interval from the start of any immediately prior emergency department visit through the observation visit to the discharge of the given encounter
*/
define fluent function hospitalizationWithObservation(TheEncounter Encounter ):
  TheEncounter Visit
  		let ObsVisit: Last([Encounter: "Observation Services"] LastObs
  				where LastObs.status = 'finished'
            and LastObs.period ends 1 hour or less on or before start of Visit.period
  				sort by end of period
  			),
  			VisitStart: Coalesce(start of ObsVisit.period, start of Visit.period),
  			EDVisit: Last([Encounter: "Emergency Department Visit"] LastED
  				where LastED.status = 'finished'
            and LastED.period ends 1 hour or less on or before VisitStart
  				sort by end of period
  			)
  		return Interval[Coalesce(start of EDVisit.period, VisitStart), end of Visit.period]

define function ToConcept(concept FHIR.CodeableConcept):
    if concept is null then
        null
    else
        System.Concept {
            codes: concept.coding C return ToCode(C),
            display: concept.text.value
        }

/*
@description: Returns true if the given MedicationRequest has a category of Community
*/
define fluent function isCommunity(medicationRequest MedicationNotRequested):
  exists (medicationRequest.category C
    where C ~ Community
  )

/*
@description: Returns true if the given MedicationRequest has a category of Discharge
*/
define fluent function isDischarge(medicationRequest MedicationNotRequested):
  exists (medicationRequest.category C
    where C ~ Discharge
  )