define "Has Hospice":
	exists (
    [Encounter: "Encounter Inpatient"] DischargeHospice
			where DischargeHospice.status = 'finished'
		    and (
	        DischargeHospice.hospitalization.dischargeDisposition ~ "Discharge to home for hospice care (procedure)"
				    or DischargeHospice.hospitalization.dischargeDisposition ~ "Discharge to healthcare facility for hospice care (procedure)"
	    	)
				and DischargeHospice.period ends during "Measurement Period"
	)
    or exists (
      [ServiceRequest: "Hospice care ambulatory"] HospiceOrder
        where HospiceOrder.intent = 'order'
            and HospiceOrder.authoredOn in "Measurement Period"
    )
    or exists (
      [Procedure: "Hospice care ambulatory"] HospicePerformed
        where HospicePerformed.status = 'completed'
          and Global."Normalize Interval"(HospicePerformed.performed) overlaps "Measurement Period"
    )

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

define "SDE Ethnicity":
  (flatten (
      Patient.extension Extension
        where Extension.url = 'http://hl7.org/fhir/us/core/StructureDefinition/us-core-ethnicity'
          return Extension.extension
    )) E
      where E.url = 'ombCategory'
        or E.url = 'detailed'
      return E.value as Coding

define "SDE Race":
  (flatten (
      Patient.extension Extension
        where Extension.url = 'http://hl7.org/fhir/us/core/StructureDefinition/us-core-race'
          return Extension.extension
    )) E
      where E.url = 'ombCategory'
        or E.url = 'detailed'
      return E.value as Coding

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

define "Numerator":
  exists ( [Immunization: "Pneumococcal Vaccine"] PneumococcalVaccine
        where PneumococcalVaccine.status = 'completed'
          and PneumococcalVaccine.occurrence as dateTime on or before
          end of "Measurement Period"
    )
      or exists ( [Procedure: "Pneumococcal Vaccine Administered"] PneumococcalVaccineGiven
          where PneumococcalVaccineGiven.status = 'completed'
            and PneumococcalVaccineGiven.performed as Period on or before
            end of "Measurement Period"
      )

define "Qualifying Encounters":
  ( [Encounter: "Office Visit"]
      union [Encounter: "Annual Wellness Visit"]
      union [Encounter: "Preventive Care Services - Established Office Visit, 18 and Up"]
      union [Encounter: "Preventive Care Services-Initial Office Visit, 18 and Up"]
      union [Encounter: "Home Healthcare Services"]
      union [Encounter: "Discharge Services - Nursing Facility"]
      union [Encounter: "Nursing Facility Visit"]
      union [Encounter: "Care Services in Long-Term Residential Facility"] ) ValidEncounter
      where ValidEncounter.period during "Measurement Period"
        and ValidEncounter.status = 'finished'

define "Initial Population":
  Global."CalendarAgeInYearsAt" ( FHIRHelpers.ToDate ( Patient.birthDate ), start of "Measurement Period" ) >= 65
      and exists "Qualifying Encounters"

define "Denominator":
  "Initial Population"

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

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

define "Denominator Exclusions":
  Hospice."Has Hospice"

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

define function "CalendarAgeInYearsAt"(BirthDateTime DateTime, AsOf DateTime):
	years between ToDate(BirthDateTime)and ToDate(AsOf)

define function "ToDate"(Value DateTime):
	DateTime(year from Value, month from Value, day from Value, 0, 0, 0, 0, timezoneoffset from Value)

/*
*
*    CQFMeasures Common Logic
*
*/

define function "Normalize Interval"(choice Choice<FHIR.dateTime, FHIR.Period, FHIR.Timing, FHIR.instant, FHIR.string, FHIR.Age, FHIR.Range>):
  case
	  when choice is FHIR.dateTime then
    	Interval[FHIRHelpers.ToDateTime(choice as FHIR.dateTime), FHIRHelpers.ToDateTime(choice as FHIR.dateTime)]
		when choice is FHIR.Period then
  		FHIRHelpers.ToInterval(choice as FHIR.Period)
		when choice is FHIR.instant then
			Interval[FHIRHelpers.ToDateTime(choice as FHIR.instant), FHIRHelpers.ToDateTime(choice as FHIR.instant)]
		when choice is FHIR.Age then
		  Interval[FHIRHelpers.ToDate(Patient.birthDate) + FHIRHelpers.ToQuantity(choice as FHIR.Age),
			  FHIRHelpers.ToDate(Patient.birthDate) + FHIRHelpers.ToQuantity(choice as FHIR.Age) + 1 year)
		when choice is FHIR.Range then
		  Interval[FHIRHelpers.ToDate(Patient.birthDate) + FHIRHelpers.ToQuantity((choice as FHIR.Range).low),
			  FHIRHelpers.ToDate(Patient.birthDate) + FHIRHelpers.ToQuantity((choice as FHIR.Range).high) + 1 year)
		when choice is FHIR.Timing then
		  Message(null as Interval<DateTime>, true, '1', 'Error', 'Cannot compute a single interval from a Timing type')
    when choice is FHIR.string then
      Message(null as Interval<DateTime>, true, '1', 'Error', 'Cannot compute an interval from a String value')
		else
			null as Interval<DateTime>
	end

define function ToString(value AdministrativeGender): value.value

define function ToString(value ImmunizationStatus): value.value

define function ToDateTime(value dateTime): value.value

define function ToString(value ProcedureStatus): value.value

/*
@description: Converts the given [Period](https://hl7.org/fhir/datatypes.html#Period)
value to a CQL DateTime Interval
@comment: If the start value of the given period is unspecified, the starting
boundary of the resulting interval will be open (meaning the start of the interval
is unknown, as opposed to interpreted as the beginning of time).
*/
define function ToInterval(period FHIR.Period):
    if period is null then
        null
    else
        if period."start" is null then
            Interval(period."start".value, period."end".value]
        else
            Interval[period."start".value, period."end".value]

define function ToDate(value date): value.value

define function ToString(value EncounterStatus): value.value

define function ToString(value uri): value.value

/*
@description: Converts the given FHIR [CodeableConcept](https://hl7.org/fhir/datatypes.html#CodeableConcept) value to a CQL Concept.
*/
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: Converts the given FHIR [Coding](https://hl7.org/fhir/datatypes.html#Coding) value to a CQL Code.
*/
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
        }

define function ToString(value ServiceRequestIntent): value.value

define function ToDateTime(value instant): value.value

/*
@description: Converts the given FHIR [Quantity](https://hl7.org/fhir/datatypes.html#Quantity) 
value to a CQL Quantity
@comment: If the given quantity has a comparator specified, a runtime error is raised. If the given quantity
has a system other than UCUM (i.e. `http://unitsofmeasure.org`) or CQL calendar units (i.e. `http://hl7.org/fhirpath/CodeSystem/calendar-units`)
an error is raised. For UCUM to calendar units, the `ToCalendarUnit` function is used.
@seealso: ToCalendarUnit
*/
define function ToQuantity(quantity FHIR.Quantity):
    case
        when quantity is null then null
        when quantity.value is null then null
        when quantity.comparator is not null then
            Message(null, true, 'FHIRHelpers.ToQuantity.ComparatorQuantityNotSupported', 'Error', 'FHIR Quantity value has a comparator and cannot be converted to a System.Quantity value.')
        when quantity.system is null or quantity.system.value = 'http://unitsofmeasure.org'
              or quantity.system.value = 'http://hl7.org/fhirpath/CodeSystem/calendar-units' then
            System.Quantity { value: quantity.value.value, unit: ToCalendarUnit(Coalesce(quantity.code.value, quantity.unit.value, '1')) }
        else
            Message(null, true, 'FHIRHelpers.ToQuantity.InvalidFHIRQuantity', 'Error', 'Invalid FHIR Quantity code: ' & quantity.unit.value & ' (' & quantity.system.value & '|' & quantity.code.value & ')')
    end

/*
@description: Converts a UCUM definite duration unit to a CQL calendar duration
unit using conversions specified in the [quantities](https://cql.hl7.org/02-authorsguide.html#quantities) 
topic of the CQL specification.
@comment: Note that for durations above days (or weeks), the conversion is understood to be approximate
*/
define function ToCalendarUnit(unit System.String):
    case unit
        when 'ms' then 'millisecond'
        when 's' then 'second'
        when 'min' then 'minute'
        when 'h' then 'hour'
        when 'd' then 'day'
        when 'wk' then 'week'
        when 'mo' then 'month'
        when 'a' then 'year'
        else unit
    end