define "HIV Status Positive Condition":
  [Condition: Concepts."HIV-positive - HIV.B.DE116"] C
    where C.clinicalStatus ~ ConceptsCustom."active"
      and exists(C.category CC where CC ~ ConceptsCustom."encounter-diagnosis")
    sort by start of onset.toInterval()

define "HIV Status Positive Condition":
  Elements."HIV Status Positive Condition" C
  where C.onset before end of "Measurement Period"

/* End of HIV-inconclusive */

/*
@dataElement: HIV.B.DE115 - HIV status
@activity: HIV.B7 Test for HIV using testing algorithm
@description: HIV status reported after applying the national HIV testing algorithm. No single HIV test can provide an HIV-positive diagnosis.
*/
define "HIV Status Observation":
  [Observation: Concepts."HIV status"] O
    where O.status in { 'final', 'amended', 'corrected' }

define "HIV Status Positive Observation":
"HIV Status Observation" O
    where O.value ~ Concepts."HIV-positive - HIV.B.DE116"
      sort by start of effective.toInterval()

define "HIV Status Positive Observation":
  Elements."HIV Status Positive Observation" O
  where O.issued before end of "Measurement Period"
  or O.effective.toInterval() starts before end of "Measurement Period"

define "Has HIV-positive Status":
  exists "HIV Status Positive Condition"
  or exists "HIV Status Positive Observation"

/* End of Syphilis test date B.DE249 */

/*
@dataElement: HIV.B.DE250 - Syphilis test result
@activity: HIV.B23 Offer sexual and reproductive health services
@description: Result from syphilis test
*/

define "Syphilis test result B.DE250":
  [Observation: Concepts."Syphilis test result - HIV.B.DE250"] O
    where O.status in { 'final', 'amended', 'corrected' }

/* End of Syphilis test result B.DE250 */

/*
@dataElement: HIV.B.DE251 - Positive
@activity: HIV.B23 Offer sexual and reproductive health services
@description: Test result is positive for syphilis
*/

define "Positive B.DE251":
  "Syphilis test result B.DE250" O
    where O.status in { 'final', 'amended', 'corrected' }
      and O.value ~ Concepts."Positive - HIV.B.DE251"

/* End of Any STI syndrome diagnosed B.DE235 */

/*
@dataElement: HIV.B.DE249 - Syphilis test date
@activity: HIV.B23 Offer sexual and reproductive health services
@description: Date of syphilis test
*/

define "Syphilis test date B.DE249":
  [Procedure] P
  where P.status = 'completed'
  and P.code ~ ConceptsCustom."syphilis test"

/**
 * Numerator
 * 
 * Definition: Number of people living with HIV who tested positive for syphilis during the reporting period (tested positive on both nontreponemal and treponemal tests or tested positive on either nontreponemal or treponemal test)
 * Calculation: COUNT of clients with "HIV status"='HIV-positive' AND with "Syphilis test date" in the reporting period AND "Syphilis test result"='Positive'
 */

define "Numerator":
  HIE."Has HIV-positive Status"
  and exists(HE."Positive B.DE251" S
  with HE."Syphilis test date B.DE249" P
  such that S.partOf.references(P) and P.performed.toInterval() during "Measurement Period")

/* End of Any STI syndrome diagnosed B.DE235 */

/*
@dataElement: HIV.B.DE249 - Syphilis test date
@activity: HIV.B23 Offer sexual and reproductive health services
@description: Date of syphilis test
*/

define "Syphilis test date B.DE249":
  exists(Elements."Syphilis test date B.DE249" P
    where P.performed.toInterval() during "Measurement Period")

/**
 * Denominator
 *
 * Definition: Number of people living with HIV tested for syphilis while attending HIV care and treatment services during the reporting period
 * Calculation: COUNT of clients with "HIV status"='HIV-positive' AND "Syphilis test date" in the reporting period
 */

define "Denominator":
  HIE."Has HIV-positive Status"
  and HIE."Syphilis test date B.DE249"

/* Populations */

/*
 *Initial Population
 */

define "Initial Population":
  true

/*
@dataElement: HIV.A.DE18 - Gender
@activity: HIV.A6.1 Review sociodemographic data with client | HIV.A5 Create new client record
@description: Gender of the client
*/

/*
 * By Administrative Gender of Patient Stratifier
 * Need to expand codes
 */

define "By Administrative Gender Stratifier":
  case 
      when Patient.gender = 'male' then Concepts."Male"
      when Patient.gender = 'female' then Concepts."Female"
      when Patient.gender = 'transgender female' then Concepts."Transgender female"
      when Patient.gender = 'transgender male' then Concepts."Transgender male"
      else Concepts."Other - HIV.A.DE23"
  end

/* End of Visit date A.DE3 */

/*
@dataElement: HIV.A.DE17 - Age
@activity: HIV.A6.1 Review sociodemographic data with client | HIV.A5 Create new client record
@description: Calculated age (number of years) of the client based on date of birth
*/
define "Age In Years":
  AgeInYearsAt(start of "Measurement Period")

define "By Age Stratifier 9":
  case 
      when "Age In Years" >= 15 and "Age In Years"<= 19 then '15-19'
      when "Age In Years" <= 24 then '20-24'
      when "Age In Years" <= 29 then '25–29'
      when "Age In Years" <= 49 then '30–49'
      when "Age In Years" >= 50 then '50+'
      else null
  end

// Geographic Region
define "By Geographic Region Stratifier":
    First(Patient.address A where A.use in { 'home' }).state

/* End of Key population member B.DE49 */

/*
@dataElement: HIV.B.DE50 - Key population member type
@activity: HIV.B6 Capture or update client history
@description: The type of key population that the client is included in
*/
define "Key population member type Observation":
  [Observation: Concepts."Key population member - HIV.B.DE49"] O
    where O.status in { 'final', 'amended', 'corrected' }
    and exists(O.category OC where OC ~ ConceptsCustom."social-history")

define "Key population member type Observation":
  Elements."Key population member type Observation" O
    where O.effective.toInterval() before end of "Measurement Period"
    or O.issued before end of "Measurement Period"

// Stratifier
define patientGroups:
  "Key population member type Observation" O
  return Combine(O.code.coding.code, ':')

define "Stratification":
 HIE."By Administrative Gender Stratifier".code 
  + ':' + HIE."By Age Stratifier 9"
+ ':' + HIE."By Geographic Region Stratifier"
+ Combine(HIE.patientGroups, ':')

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
        }

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 ToDateTime(value dateTime): value.value

define function ToString(value ObservationStatus): value.value

define function ToDateTime(value instant): value.value

define function ToString(value ProcedureStatus): value.value

/*
@description: Returns true if any of the given references are to the given resource
@comment: Returns true if the `id` element of the given resource exactly equals the tail of any of the given references.
NOTE: This function assumes resources from the same source server.
*/
define fluent function references(references List<FHIR.Reference>, resource FHIR.Resource):
  exists (references R where R.references(resource))

/*
@description: Returns true if the given reference is to the given resource
@comment: Returns true if the `id` element of the given resource exactly equals the tail of the given reference.
NOTE: This function assumes resources from the same source server.
*/
define fluent function references(reference FHIR.Reference, resource FHIR.Resource):
  resource.id = Last(Split(reference.reference, '/'))

define function ToString(value string): value.value

define function ToString(value AdministrativeGender): value.value

define function ToString(value AddressUse): value.value