define "Is Infant Patient":
  Patient.birthDate is not null
  and difference in years between Patient.birthDate and start of "Measurement Period" < 1

/* End of Age of infant */

/*
@dataElement: HIV.E.DE112 - HIV-exposed infant or child
@activity: HIV.F6 Check whether infant/child had HIV exposure
@description: Whether the infant or child was determined to have had HIV exposure
*/
define "HIV-exposed infant or child E.DE112":

  [Observation: Concepts."HIV-exposed infant or child - HIV.E.DE112"] O
    where O.status in { 'final', 'amended', 'corrected' }

/* End of Age of infant */

/*
@dataElement: HIV.E.DE112 - HIV-exposed infant or child
@activity: HIV.F6 Check whether infant/child had HIV exposure
@description: Whether the infant or child was determined to have had HIV exposure
*/
define "is HIV-exposed infant or child E.DE112":
  "Is Infant Patient" and 
  exists(Elements."HIV-exposed infant or child E.DE112" O
    where O.effective.toInterval() during "Measurement Period")

/* End of Newly on ART during labour and delivery */

/*
@dataElement: HIV.E.DE46 - Delivery date
@activity: HIV.E1 Capture or update mother's history
@description: Date on which the woman delivered
*/
define "Live Birth Delivery":
  [Observation: Concepts."Live birth"] O
    where O.status in { 'final', 'amended', 'corrected' }

/* End of Newly on ART during labour and delivery */

/*
@dataElement: HIV.E.DE46 - Delivery date
@activity: HIV.E1 Capture or update mother's history
@description: Date on which the woman delivered
*/
define "Live Birth Delivery":
  Elements."Live Birth Delivery" O
    where O.effective.toInterval() during "Measurement Period"

/* End of Currently pregnant B.DE29 */

/*
@dataElement: HIV.B.DE32 - Breastfeeding
@activity: HIV.B6 Capture or update client history
@description: Infant is being breastfed by mother
*/

define "Breastfeeding B.DE32":
  [Observation: Concepts."Breastfeeding - HIV.B.DE32"] O
    where O.status in { 'final', 'amended', 'corrected' }
      and O.value is true

/* End of Currently pregnant B.DE29 */

/*
@dataElement: HIV.B.DE32 - Breastfeeding
@activity: HIV.B6 Capture or update client history
@description: Infant is being breastfed by mother
*/

define "Breastfeeding B.DE32":
  Elements."Breastfeeding B.DE32" O
    where O.effective.toInterval() during "Measurement Period"

/* End of First visit after the end of breastfeeding */

/*
@dataElement: HIV.E.DE179 - Registered in birth cohort
@activity: HIV.F3 Capture or update infant's/child's history
@description: Whether the infant has been registered in a birth cohort
*/

define "Registered in birth cohort":
  [Observation: Concepts."Registered in birth cohort"] O
    where O.status in { 'final', 'amended', 'corrected' }
      and O.value is true

/* End of First visit after the end of breastfeeding */

/*
@dataElement: HIV.E.DE179 - Registered in birth cohort
@activity: HIV.F3 Capture or update infant's/child's history
@description: Whether the infant has been registered in a birth cohort
*/

define "Registered in birth cohort":
  exists Elements."Registered in birth cohort" O
    where O.effective.toInterval() during "Measurement Period"

define "Final diagnosis of HIV-exposed infant E.DE230 Observation":
  [Observation: Concepts."Final diagnosis of HIV-exposed infant - HIV.E.DE230"] O
    where O.status in { 'final', 'amended', 'corrected' }

/* End of Infant ART start date */

/*
@dataElement: HIV.E.DE230 - Final diagnosis of HIV-exposed infant
@activity: HIV.F20 Record infant's/child's final HIV diagnosis
@description: HIV-exposed infant final status at 18 months or 3 months after cessation of breastfeeding (whichever is later).
*/

define "Final diagnosis of HIV-exposed infant E.DE230":
  First("Final diagnosis of HIV-exposed infant E.DE230 Observation".value) as FHIR.CodeableConcept

/**
 * Numerator
 * 
 * Definition: HIV-exposed infants born within the past 12 months (or 24 months in breastfeeding settings) who have known final HIV outcome status
 * Calculation: COUNT of infants who are an "HIV-exposed infant or child" AND [(with an "Infant date of birth" in past 12 months) OR (with an "Infant date of birth" in past 24 months IF mothers are "Breastfeeding")] AND "Registered in birth cohort"=True AND with a "Final diagnosis of HIV-exposed infant" of NOT NULL
 */

define "Numerator":
  HIE."is HIV-exposed infant or child E.DE112"
  and
  (exists(HIE."Live Birth Delivery" B where months between end of B.effective.toInterval() and end of  "Measurement Period" < 12 months)
  or 
  (
  exists(HIE."Breastfeeding B.DE32" B) and
  exists(HIE."Live Birth Delivery" B where months between end of B.effective.toInterval() and end of  "Measurement Period" < 24 months)
  )
  )
  and HIE."Registered in birth cohort"
  and HE."Final diagnosis of HIV-exposed infant E.DE230" is not null

/**
 * Denominator
 *
 * Definition: a) Programme-based/service delivery denominator | Number of HIV-exposed infants who were born within the 12 months (or 24 months in breastfeeding settings) prior to the reporting period and registered in the birth cohort | For example, for the reporting period January to December 2021 the denominator would be the number of HIV-exposed infants born between January to December 2020 in non-breast feeding settings and January to December 2019 in breastfeeding settings. |  | b) Population-based denominator | Estimated number of HIV-positive women who delivered within the past 12 months | (or 24 months in breastfeeding settings)
 * Calculation: COUNT of infants who are an "HIV-exposed infant or child" AND [(with an "Infant date of birth" within past 12 months) OR (with an "Infant date of birth" within past 24 months IF mothers are "Breastfeeding")] AND "Registered in birth cohort"=True
 */

define "Denominator":
  HIE."is HIV-exposed infant or child E.DE112"
  and
  (exists(HIE."Live Birth Delivery" B where months between end of B.effective.toInterval() and end of  "Measurement Period" < 12 months)
  or 
  (
  exists(HIE."Breastfeeding B.DE32" B) and
  exists(HIE."Live Birth Delivery" B where months between end of B.effective.toInterval() and end of  "Measurement Period" < 24 months)
  )
  )
  and HIE."Registered in birth cohort"

/* Populations */

/*
 *Initial Population
 */

define "Initial Population":
  true

define function ToDate(value date): value.value

define function ToString(value ObservationStatus): value.value

define function ToBoolean(value boolean): value.value