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 Refused stopped treatment */

/*
@dataElement: HIV.H.DE47 - On ART
@activity: HIV.H3 Record outreach and result
@description: Client is currently taking ART 
*/

define "On ART H.DE47":
    [MedicationStatement] MS
    where exists(MS.reasonCode C where C ~ Concepts."On ART - HIV.H.DE47")
    sort by start of effective.toInterval()

/* End of Refused stopped treatment */

/*
@dataElement: HIV.H.DE47 - On ART
@activity: HIV.H3 Record outreach and result
@description: Client is currently taking ART 
*/
define "On ART H.DE47":
  exists(Elements."On ART H.DE47" ART
   where ART.effective.toInterval() during "Measurement Period"
   )

/* End of Date DSD ART eligibility assessed */

/*
@dataElement: HIV.D.DE762 - Currently enrolled in DSD ART model
@activity: HIV.D21 Determine regimen and treatment options
@description: Client currently enrolled in differentiated service delivery (DSD) ART model
*/

define "Currently enrolled in DSD ART model":
  exists(
    [EpisodeOfCare] EOC
    where exists(EOC.type T where T ~ Concepts."Currently enrolled in DSD ART model")
    and (exists (
      EOC.statusHistory H
      where H.period starts after start of "Measurement Period"
      and H.period starts before end of "Measurement Period"
    ) 
    or (
      EOC.period starts after start of "Measurement Period"
      and EOC.period starts before end of "Measurement Period"
    )
    )
  )

/**
 * Numerator
 * 
 * Definition: Number of people living with HIV enrolled in DSD ART models during the reporting period
 * Calculation: COUNT of clients with "HIV status"='HIV-positive' AND "On ART"=True AND "Currently enrolled in DSD ART model"=True
 */

define "Numerator":
    HIE."Has HIV-positive Status"
   and HIE."On ART H.DE47"
   and HIE."Currently enrolled in DSD ART model"

/* End of Eligible for DSD ART */

/*
@dataElement: HIV.D.DE761 - Date DSD ART eligibility assessed
@activity: HIV.D21 Determine regimen and treatment options
@description: Date client was assessed for eligibility for differentiated service delivery (DSD) for ART
*/

define "Date DSD ART eligibility assessed":
  [Procedure: ConceptsCustom."DSD ART eligibility assessed"] P
    where P.status in { 'completed' }
  return P.performed.toInterval()

/* End of Eligible for DSD ART */

/*
@dataElement: HIV.D.DE761 - Date DSD ART eligibility assessed
@activity: HIV.D21 Determine regimen and treatment options
@description: Date client was assessed for eligibility for differentiated service delivery (DSD) for ART
*/

define "Date DSD ART eligibility assessed":
  exists(Elements."Date DSD ART eligibility assessed" P where P during "Measurement Period")

/* End of Malaria prevention such as bed nets and prophylaxis, depending on epidemiology D.DE759 */

/*
@dataElement: HIV.D.DE760 - Eligible for DSD ART
@activity: HIV.D21 Determine regimen and treatment options
@description: Client is eligible for differentiated service delivery (DSD) for ART
*/

define "Eligible for DSD ART":
  [Observation: Concepts."Eligible for DSD ART"] O
    where O.status in { 'final', 'amended', 'corrected' }
      and O.value is true

/* End of Other D.DE739 */

/*
@dataElement: HIV.D.DE760 - Eligible for DSD ART
@activity: HIV.D21 Determine regimen and treatment options
@description: Client is eligible for differentiated service delivery (DSD) for ART
*/

define "Eligible for DSD ART":
  exists Elements."Eligible for DSD ART" O
    where O.effective.toInterval() during "Measurement Period"

/**
 * Denominator
 *
 * Definition: Facilities with electronic health information systems: Number of people living with HIV on ART eligible for DSD ART models during the reporting period |  | Facilities with paper-based systems: Number of people living with HIV receiving ART at the end of the reporting period
 * Calculation: COUNT of clients with "HIV status"='HIV-positive' AND "On ART"=True AND "Date DSD ART eligibility assessed" within the reporting period AND "Eligible for DSD ART"=True
 */

define "Denominator":
  HIE."Has HIV-positive Status"
   and HIE."On ART H.DE47"
  and HIE."Date DSD ART eligibility assessed"
  and HIE."Eligible for DSD ART"

/* 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")

//(0–4, 5–14, 15–24, 25+ years) 
define "By Age Stratifier 8":
  case 
      when "Age In Years" <= 4 then '0-4'
      when "Age In Years" <= 14 then '5-14'
      when "Age In Years" <= 24 then '15-24'
      when "Age In Years" >= 25 then '25+'
      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, ':')

/* End of DSD ART models */

/*
@dataElement: HIV.D.DE765 - Fast track ART refill
@activity: HIV.D21 Determine regimen and treatment options
@description: Client is enrolled in fast track ART refill (DSD ART model)
*/

define "Fast track ART refill":
  exists(
    [EpisodeOfCare] EOC
    where exists(EOC.type T where T ~ Concepts."Fast track ART refill")
    and (exists (
      EOC.statusHistory H
      where H.period starts after start of "Measurement Period"
      and H.period starts before end of "Measurement Period"
    ) 
    or (
      EOC.period starts after start of "Measurement Period"
      and EOC.period starts before end of "Measurement Period"
    )
    )
  )

/* End of Fast track ART refill */

/*
@dataElement: HIV.D.DE766 - Facility adherence club
@activity: HIV.D21 Determine regimen and treatment options
@description: Client is enrolled in facility adherence club (DSD ART model)
*/

define "Facility adherence club":
  exists(
    [EpisodeOfCare] EOC
    where exists(EOC.type T where T ~ Concepts."Facility adherence club")
    and (exists (
      EOC.statusHistory H
      where H.period starts after start of "Measurement Period"
      and H.period starts before end of "Measurement Period"
    ) 
    or (
      EOC.period starts after start of "Measurement Period"
      and EOC.period starts before end of "Measurement Period"
    )
    )
  )

/* End of Facility adherence club */

/*
@dataElement: HIV.D.DE767 - Community ART distribution point
@activity: HIV.D21 Determine regimen and treatment options
@description: Client is enrolled in community ART distribution point (DSD ART model)
*/

define "Community ART distribution point":
  exists(
    [EpisodeOfCare] EOC
    where exists(EOC.type T where T ~ Concepts."Community ART distribution point")
    and (exists (
      EOC.statusHistory H
      where H.period starts after start of "Measurement Period"
      and H.period starts before end of "Measurement Period"
    ) 
    or (
      EOC.period starts after start of "Measurement Period"
      and EOC.period starts before end of "Measurement Period"
    )
    )
  )

/* End of Community ART distribution point */

/*
@dataElement: HIV.D.DE768 - CHW/peer educator community ART group
@activity: HIV.D21 Determine regimen and treatment options
@description: Client is enrolled in community health worker/peer educator community ART group (DSD ART model)
*/

define "CHW/peer educator community ART group":
  exists(
    [EpisodeOfCare] EOC
    where exists(EOC.type T where T ~ Concepts."CHW/peer educator community ART group")
    and (exists (
      EOC.statusHistory H
      where H.period starts after start of "Measurement Period"
      and H.period starts before end of "Measurement Period"
    ) 
    or (
      EOC.period starts after start of "Measurement Period"
      and EOC.period starts before end of "Measurement Period"
    )
    )
  )

/* End of CHW/peer educator community ART group */

/*
@dataElement: HIV.D.DE769 - Patient/client community ART group
@activity: HIV.D21 Determine regimen and treatment options
@description: Client is enrolled in patient/client community ART group (DSD ART model)
*/

define "Patient/client community ART group":
  exists(
    [EpisodeOfCare] EOC
    where exists(EOC.type T where T ~ Concepts."Patient/client community ART group")
    and (exists (
      EOC.statusHistory H
      where H.period starts after start of "Measurement Period"
      and H.period starts before end of "Measurement Period"
    ) 
    or (
      EOC.period starts after start of "Measurement Period"
      and EOC.period starts before end of "Measurement Period"
    )
    )
  )

/* End of Patient/client community ART group */

/*
@dataElement: HIV.D.DE770 - Other DSD ART model
@activity: HIV.D21 Determine regimen and treatment options
@description: Client is enrolled in another DSD ART model
*/

define "Other DSD ART model":
  exists(
    [EpisodeOfCare] EOC
    where exists(EOC.type T where T ~ Concepts."Other DSD ART model")
    and (exists (
      EOC.statusHistory H
      where H.period starts after start of "Measurement Period"
      and H.period starts before end of "Measurement Period"
    ) 
    or (
      EOC.period starts after start of "Measurement Period"
      and EOC.period starts before end of "Measurement Period"
    )
    )
  )

/* End of DSD ART start date */

/*
@dataElement: HIV.D.DE764 - DSD ART models
@activity: HIV.D21 Determine regimen and treatment options
@description: Type of DSD ART model client is enrolled in (country-specific)
*/

define "DSD ART models":
    case
    when "Fast track ART refill" then Concepts."Fast track ART refill"
    when "Facility adherence club" then Concepts."Facility adherence club"
    when "Community ART distribution point" then Concepts."Community ART distribution point"
    when "CHW/peer educator community ART group" then Concepts."CHW/peer educator community ART group"
    when "Patient/client community ART group" then Concepts."Patient/client community ART group"
    when "Other DSD ART model" then Concepts."Other DSD ART model"
    else null
  end

define "Stratification":
 HIE."By Administrative Gender Stratifier".code 
  + ':' + HIE."By Age Stratifier 8"
+ ':' + HIE."By Geographic Region Stratifier"
+ Combine(HIE.patientGroups, ':')
+  HIE."DSD ART models".code

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 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 ToString(value ProcedureStatus): value.value

define function ToBoolean(value boolean): value.value

define function ToString(value AdministrativeGender): value.value

define function ToString(value string): value.value

define function ToString(value AddressUse): value.value