/* End of HIV prevention intervention */

/*
@dataElement: HIV.PRV.DE3 - PrEP service
@activity: HIV.B6 Capture or update client history
@description: Client accessed PrEP services
*/

define "PrEP service":
  [MedicationStatement] MS
    where exists(MS.reasonCode C where C ~ Concepts."PrEP for HIV prevention")
    sort by start of effective.toInterval()

/* End of Date informed of HIV-positive diagnosis */

/*
@activity: HIV.B7 Test for HIV using testing algorithm
*/
define "HIV test":
  [Observation: Concepts."HIV test type - HIV.B.DE81 Choices"] O
  where O.status in { 'final', 'amended', 'corrected' }

/* End of HIV test date B.DE110 */

/*
@dataElement: HIV.B.DE111 - HIV test result
@activity: HIV.B7 Test for HIV using testing algorithm
@description: The result from HIV testing after applying the testing algorithm
*/
// Same as test - see profile
define "HIV test result Observation":
  "HIV test" O

/* End of HIV-positive B.DE112 */

/*
@dataElement: HIV.B.DE113 - HIV-negative
@activity: HIV.B7 Test for HIV using testing algorithm
@description: Test result is HIV-negative
*/
define "HIV-negative test result":
  "HIV test result Observation" O
    where O.value ~ Concepts."HIV-negative - HIV.B.DE113"

define "Negative Tests within Measurement Period":
  Elements."HIV-negative test result" O
    // with Elements."At elevated risk for HIV acquisition B.DE225" HIV
    // such that O.hasMember.references(HIV)
    where O.effective.toInterval() starts during "Measurement Period"
    sort by start of effective.toInterval()

define "First Negative Test within Measurement Period":
  (First("Negative Tests within Measurement Period"))

define "OAMT status":
    [EpisodeOfCare] EOC
    where exists(EOC.type T where T ~ Concepts."OAMT")
    return EOC.period

define "OAMT statusHistory":
    [EpisodeOfCare] EOC
    where exists(EOC.type T where T ~ Concepts."OAMT") 
    and (exists (
      EOC.statusHistory H
      where H.period is not null))

/* End of PrEP service */

/*
@dataElement: HIV.PRV.DE4 - OAMT
@activity: HIV.B6 Capture or update client history
@description: Client accessed opioid agonist maintenance treatment (OAMT) services
*/

define "OAMT":
  flatten{"OAMT status","OAMT statusHistory".statusHistory.period}

// TODO: fix device use statement 
  // [DeviceUseStatement] DUS
  // with [Device: ConceptsCustom."needle-syringe"] D
  //     such that DUS.reasonReference.references(D) 
  //       and D.status in { 'active' }
  // where DUS.status = 'completed'

  // define "NSP date":
  // [DeviceUseStatement] DUS
  // with [Device: ConceptsCustom."needle-syringe"] D
  //     such that DUS.reasonReference.references(D) 
  //       and D.status in { 'active' }
  // where DUS.status = 'completed'
  // return start of DUS.timing.toInterval()
/* End of NSP */

/*
@dataElement: HIV.PRV.DE6 - STI services
@activity: HIV.B6 Capture or update client history
@description: Client accessed sexually transmitted infection (STI) services
*/

define "STI services":
  [Procedure] P
  where P.status = 'completed'
  and P.code ~ Concepts."STI testing and treatment services"

/* End of STI services */

/*
@dataElement: HIV.PRV.DE7 - VMMC
@activity: HIV.B6 Capture or update client history
@description: Client accessed voluntary medical male circumcision (VMMC) services
*/
// define "VMMC_done":
// [Procedure] P
//   where P.status = 'completed'
//   and P.code ~ Concepts."Voluntary medical male circumcision VMMC"


define "VMMC":
  [Procedure] P
  where P.status = 'completed'
  and P.code ~ Concepts."VMMC procedure"

/* End of VMMC */

/*
@dataElement: HIV.PRV.DE8 - Other
@activity: HIV.B6 Capture or update client history
@description: Client accessed other HIV prevention services
*/

define "Other PRV.DE8":
  [Observation] O
    where O.status in {'final', 'amended'}
    and O.code ~ Concepts."HIV prevention intervention"
    and O.value ~ Concepts."Other - HIV.PRV.DE8"
    sort by start of effective.toInterval()

/* End of HIV retest prior to starting ART conducted */

/*
@dataElement: HIV.B.DE225 - At elevated risk for HIV acquisition
@activity: HIV.B6 Capture or update client history
@description: Client is at elevated risk for HIV acquisition
*/

define "At elevated risk for HIV acquisition B.DE225":
  [Condition] C
    where C.code ~ Concepts."At elevated risk for HIV acquisition - HIV.B.DE225"

/* End of Other B.DE222 */

/*
@dataElement: HIV.B.DE225 - At elevated risk for HIV acquisition
@activity: HIV.B6 Capture or update client history
@description: Client is at elevated risk for HIV acquisition
*/

define "At elevated risk for HIV acquisition B.DE225":
  exists(Elements."At elevated risk for HIV acquisition B.DE225" C
    where C.prevalenceInterval() overlaps "Measurement Period")

/**
 * Numerator
 * 
 * Definition: Number of people who receive an HIV prevention intervention within a defined period after receiving a negative HIV test result
 * Calculation: COUNT of clients with "At elevated risk for HIV acquisition"=True and with "Date accessed HIV prevention intervention" within X days of "HIV test date" in the reporting period with "HIV test result"='HIV-negative' |  | where X is 7, 14, or 28 days
 */

define "Numerator":
  (exists(HE."PrEP service" prep
   where prep.effective.toInterval() starts before (start of HIE."First Negative Test within Measurement Period".effective.toInterval() + "Intervention Interval")
  and prep.effective.toInterval() starts after (start of HIE."First Negative Test within Measurement Period".effective.toInterval())
   )
  or 
  exists(HE."OAMT" t where t starts before (start of HIE."First Negative Test within Measurement Period".effective.toInterval() + "Intervention Interval")
      and t starts after (start of HIE."First Negative Test within Measurement Period".effective.toInterval()))
  or 
  // TODO: DeviceUseStatement causing translation issue
  // exists(HE."NSP" DUS where DUS.timing.toInterval() starts before (start of HIE."First Negative Test within Measurement Period".effective.toInterval() + "Intervention Interval")
  // and DUS.timing.toInterval() starts after (start of HIE."First Negative Test within Measurement Period".effective.toInterval()))
  // or 
  exists(HE."STI services" STI where STI.performed.toInterval() starts before (start of HIE."First Negative Test within Measurement Period".effective.toInterval() + "Intervention Interval")
  and STI.performed.toInterval() starts after (start of HIE."First Negative Test within Measurement Period".effective.toInterval()))
  or 
  exists(HE."VMMC" V where V.performed.toInterval() starts before (start of HIE."First Negative Test within Measurement Period".effective.toInterval() + "Intervention Interval")
  and V.performed.toInterval() starts after (start of HIE."First Negative Test within Measurement Period".effective.toInterval()))
  or
  exists(HE."Other PRV.DE8" O
    where O.effective.toInterval() starts before (start of HIE."First Negative Test within Measurement Period".effective.toInterval() + "Intervention Interval")
    and O.effective.toInterval() starts after (start of HIE."First Negative Test within Measurement Period".effective.toInterval())))
  and
  HIE."At elevated risk for HIV acquisition B.DE225"

/**
 * Denominator
 *
 * Definition: Number of people testing negative for HIV in the reporting period and identified as being at elevated risk for HIV acquisition (includes people requesting/receiving any HIV prevention intervention, people from key populations, people with known risk factors or those assessed as being at risk of HIV acquisition)
 * Calculation: COUNT of clients with "At elevated risk for HIV acquisition"=True AND with an "HIV test date" in the reporting period with "HIV test result"='HIV-negative'
 */

define "Denominator":
  exists(HIE."Negative Tests within Measurement Period")
  and HIE."At elevated risk for HIV acquisition B.DE225"

/* 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 5":
  case 
      when "Age In Years" < 15 then '<15'
      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" <= 49 then '25–49'
      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, ':')

/* End of HIV prevention intervention */

/*
@dataElement: HIV.PRV.DE3 - PrEP service
@activity: HIV.B6 Capture or update client history
@description: Client accessed PrEP services
*/

define "PrEP service":
  exists(Elements."PrEP service" prep
   where prep.effective.toInterval() during "Measurement Period"
   )

/* End of PrEP service */

/*
@dataElement: HIV.PRV.DE4 - OAMT
@activity: HIV.B6 Capture or update client history
@description: Client accessed opioid agonist maintenance treatment (OAMT) services
*/

define "OAMT":
  exists(Elements."OAMT" t where t during "Measurement Period")

/* End of OAMT */

/*
@dataElement: HIV.PRV.DE5 - NSP
@activity: HIV.B6 Capture or update client history
@description: Client accessed needle-syringe programme (NSP) services
*/

define "NSP":
  false

// TODO: doesn't compile DeviceUseStatement causes translation error
  //exists(Elements."NSP" DUS where DUS.timing.toInterval() during "Measurement Period")
/* End of NSP */

/*
@dataElement: HIV.PRV.DE6 - STI services
@activity: HIV.B6 Capture or update client history
@description: Client accessed sexually transmitted infection (STI) services
*/

define "STI services":
  exists(Elements."STI services" STI where STI.performed.toInterval() during "Measurement Period")

/* End of STI services */

/*
@dataElement: HIV.PRV.DE7 - VMMC
@activity: HIV.B6 Capture or update client history
@description: Client accessed voluntary medical male circumcision (VMMC) services
*/

define "VMMC":
  exists(Elements."VMMC" V where V.performed.toInterval() during "Measurement Period")

/* End of VMMC */

/*
@dataElement: HIV.PRV.DE8 - Other
@activity: HIV.B6 Capture or update client history
@description: Client accessed other HIV prevention services
*/

define "Other PRV.DE8":
  exists(Elements."Other PRV.DE8" O
    where O.effective.toInterval() during "Measurement Period")

/* End of At elevated risk for HIV acquisition PRV.DE1 */

/*
@dataElement: HIV.PRV.DE2 - HIV prevention intervention
@activity: HIV.B6 Capture or update client history
@description: HIV prevention intervention that client accessed
*/

//(including PrEP, OAMT, NSP, STI services, VMMC) 
define "HIV prevention intervention":
  List<String>{
    if "PrEP service" then 'PrEP' else null,
    if "OAMT" then 'OAMT' else null,
    if "NSP" then 'NSP' else null,
    if "STI services" then 'STI services' else null,
    if "VMMC" then 'VMMC' else null,
    if "Other PRV.DE8" then 'other prevention' else null
  }

define "Stratification":
 HIE."By Administrative Gender Stratifier".code 
  + ':' + HIE."By Age Stratifier 5"
+ ':' + HIE."By Geographic Region Stratifier"
+ Combine(HIE.patientGroups, ':')
+ Combine(HIE."HIV prevention intervention", ':')

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 ToString(value ObservationStatus): 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

/*
@description: Returns an interval representing the normalized prevalence period of a given Condition resource.
@comment: Uses the toInterval and toAbatementInterval functions to determine the widest potential interval from
onset to abatement as specified in the given Condition.
*/
define fluent function prevalenceInterval(condition Condition):
if condition.clinicalStatus ~ "active"
  or condition.clinicalStatus ~ "recurrence"
  or condition.clinicalStatus ~ "relapse" then
  Interval[start of condition.onset.toInterval(), end of condition.abatementInterval()]
else
  (end of condition.abatementInterval()) abatementDate
    return 
	  if abatementDate is null then
        Interval[start of condition.onset.toInterval(), abatementDate)
      else
        Interval[start of condition.onset.toInterval(), abatementDate]

/*
@description: Returns an interval representing the normalized Abatement of a given Condition resource.
@comment: NOTE: Due to the complexity of determining an interval from a String, this function will throw
a run-time exception if used with a Condition instance that has a String as the abatement value.
*/
define fluent function abatementInterval(condition Condition):
  if condition.abatement is FHIR.dateTime then
    Interval[FHIRHelpers.ToDateTime(condition.abatement as FHIR.dateTime), FHIRHelpers.ToDateTime(condition.abatement as FHIR.dateTime)]
  else if condition.abatement is FHIR.Period then
    FHIRHelpers.ToInterval(condition.abatement as FHIR.Period)
  else if condition.abatement is FHIR.string then
    Message(null as Interval<DateTime>, true, 'NOT_IMPLEMENTED', 'Error', 'Calculation of an interval from a String value is not supported')
  else if condition.abatement is FHIR.Age then
    Interval[FHIRHelpers.ToDate(Patient.birthDate) + FHIRHelpers.ToQuantity(condition.abatement as FHIR.Age),
      FHIRHelpers.ToDate(Patient.birthDate) + FHIRHelpers.ToQuantity(condition.abatement as FHIR.Age) + 1 year)
  else if condition.abatement is FHIR.Range then
    Interval[FHIRHelpers.ToDate(Patient.birthDate) + FHIRHelpers.ToQuantity((condition.abatement as FHIR.Range).low),
      FHIRHelpers.ToDate(Patient.birthDate) + FHIRHelpers.ToQuantity((condition.abatement as FHIR.Range).high) + 1 year)
  else if condition.abatement is FHIR.boolean then
    Interval[end of condition.onset.toInterval(), condition.recordedDate)
  else 
    null

define function ToDateTime(value dateTime): value.value

define function ToDate(value date): value.value

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

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

define function ToString(value AdministrativeGender): value.value

define function ToString(value string): value.value

define function ToString(value AddressUse): value.value

define function ToDateTime(value instant): value.value