/*
@author: Bryn Rhodes
@description: This library defines functions to convert between FHIR
 data types and CQL system-defined types, as well as functions to support
 FHIRPath implementation. For more information, see the FHIRHelpers wiki page:
 https://github.com/cqframework/clinical_quality_language/wiki/FHIRHelpers
@allowFluent: true
*/
library FHIRHelpers version '4.0.2'

using FHIR version '4.0.1'

define function ToInterval(period FHIR.Period):
    if period is null then
        null 
    else 
        if period."start".value is null then
            Interval(period."start".value, period."end".value]
        else 
            if time from period."start".value is null and time from period."end".value is not null then
                Interval[
                    DateTime(year from period."start".value, month from period."start".value, day from period."start".value,
                        0, 0, 0, 0, timezoneoffset from period."end".value), 
                    period."end".value
                ]
        else 
            if time from period."end".value is null and time from period."start".value is not null then
                Interval[
                    period."start".value, 
                    DateTime(year from period."end".value, month from period."end".value, day from period."end".value,
                        23, 59, 59, 999, timezoneoffset from period."start".value)
                ]
        else Interval[period."start".value, period."end".value]

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 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 ToQuantityIgnoringComparator(quantity FHIR.Quantity):
    case
        when quantity is null then null
        when quantity.value is null then null
        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 ToInterval(quantity FHIR.Quantity):
    if quantity is null then null else
        case quantity.comparator.value
            when '<' then
                Interval[
                    null,
                    ToQuantityIgnoringComparator(quantity)
                )
            when '<=' then
                Interval[
                    null,
                    ToQuantityIgnoringComparator(quantity)
                ]
            when '>=' then
                Interval[
                    ToQuantityIgnoringComparator(quantity),
                    null
                ]
            when '>' then
                Interval(
                    ToQuantityIgnoringComparator(quantity),
                    null
                ]
            else
                Interval[ToQuantity(quantity), ToQuantity(quantity)]
        end

define function ToRatio(ratio FHIR.Ratio):
    if ratio is null then
        null
    else
        System.Ratio { numerator: ToQuantity(ratio.numerator), denominator: ToQuantity(ratio.denominator) }

define function ToInterval(range FHIR.Range):
    if range is null then
        null
    else
        Interval[ToQuantity(range.low), ToQuantity(range.high)]

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 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 reference(reference String):
    if reference is null then
        null
    else
        Reference { reference: string { value: reference } }

define function resolve(reference String) returns Resource: external
define function resolve(reference Reference) returns Resource: external
define function reference(resource Resource) returns Reference: external
define function extension(element Element, url String) returns List<Element>: external
define function extension(resource Resource, url String) returns List<Element>: external
define function hasValue(element Element) returns Boolean: external
define function getValue(element Element) returns Any: external
define function ofType(identifier String) returns List<Any>: external
define function is(identifier String) returns Boolean: external
define function as(identifier String) returns Any: external
define function elementDefinition(element Element) returns ElementDefinition: external
define function slice(element Element, url String, name String) returns List<Element>: external
define function checkModifiers(resource Resource) returns Resource: external
define function checkModifiers(resource Resource, modifier String) returns Resource: external
define function checkModifiers(element Element) returns Element: external
define function checkModifiers(element Element, modifier String) returns Element: external
define function conformsTo(resource Resource, structure String) returns Boolean: external
define function memberOf(code code, valueSet String) returns Boolean: external
define function memberOf(coding Coding, valueSet String) returns Boolean: external
define function memberOf(concept CodeableConcept, valueSet String) returns Boolean: external
define function subsumes(coding Coding, subsumedCoding Coding) returns Boolean: external
define function subsumes(concept CodeableConcept, subsumedConcept CodeableConcept) returns Boolean: external
define function subsumedBy(coding Coding, subsumingCoding Coding) returns Boolean: external
define function subsumedBy(concept CodeableConcept, subsumingConcept CodeableConcept) returns Boolean: external
define function htmlChecks(element Element) returns Boolean: external

define function ToString(value AccountStatus): value.value
define function ToString(value ActionCardinalityBehavior): value.value
define function ToString(value ActionConditionKind): value.value
define function ToString(value ActionGroupingBehavior): value.value
define function ToString(value ActionParticipantType): value.value
define function ToString(value ActionPrecheckBehavior): value.value
define function ToString(value ActionRelationshipType): value.value
define function ToString(value ActionRequiredBehavior): value.value
define function ToString(value ActionSelectionBehavior): value.value
define function ToString(value ActivityDefinitionKind): value.value
define function ToString(value ActivityParticipantType): value.value
define function ToString(value AddressType): value.value
define function ToString(value AddressUse): value.value
define function ToString(value AdministrativeGender): value.value
define function ToString(value AdverseEventActuality): value.value
define function ToString(value AggregationMode): value.value
define function ToString(value AllergyIntoleranceCategory): value.value
define function ToString(value AllergyIntoleranceCriticality): value.value
define function ToString(value AllergyIntoleranceSeverity): value.value
define function ToString(value AllergyIntoleranceType): value.value
define function ToString(value AppointmentStatus): value.value
define function ToString(value AssertionDirectionType): value.value
define function ToString(value AssertionOperatorType): value.value
define function ToString(value AssertionResponseTypes): value.value
define function ToString(value AuditEventAction): value.value
define function ToString(value AuditEventAgentNetworkType): value.value
define function ToString(value AuditEventOutcome): value.value
define function ToString(value BindingStrength): value.value
define function ToString(value BiologicallyDerivedProductCategory): value.value
define function ToString(value BiologicallyDerivedProductStatus): value.value
define function ToString(value BiologicallyDerivedProductStorageScale): value.value
define function ToString(value BundleType): value.value
define function ToString(value CapabilityStatementKind): value.value
define function ToString(value CarePlanActivityKind): value.value
define function ToString(value CarePlanActivityStatus): value.value
define function ToString(value CarePlanIntent): value.value
define function ToString(value CarePlanStatus): value.value
define function ToString(value CareTeamStatus): value.value
define function ToString(value CatalogEntryRelationType): value.value
define function ToString(value ChargeItemDefinitionPriceComponentType): value.value
define function ToString(value ChargeItemStatus): value.value
define function ToString(value ClaimResponseStatus): value.value
define function ToString(value ClaimStatus): value.value
define function ToString(value ClinicalImpressionStatus): value.value
define function ToString(value CodeSearchSupport): value.value
define function ToString(value CodeSystemContentMode): value.value
define function ToString(value CodeSystemHierarchyMeaning): value.value
define function ToString(value CommunicationPriority): value.value
define function ToString(value CommunicationRequestStatus): value.value
define function ToString(value CommunicationStatus): value.value
define function ToString(value CompartmentCode): value.value
define function ToString(value CompartmentType): value.value
define function ToString(value CompositionAttestationMode): value.value
define function ToString(value CompositionStatus): value.value
define function ToString(value ConceptMapEquivalence): value.value
define function ToString(value ConceptMapGroupUnmappedMode): value.value
define function ToString(value ConditionalDeleteStatus): value.value
define function ToString(value ConditionalReadStatus): value.value
define function ToString(value ConsentDataMeaning): value.value
define function ToString(value ConsentProvisionType): value.value
define function ToString(value ConsentState): value.value
define function ToString(value ConstraintSeverity): value.value
define function ToString(value ContactPointSystem): value.value
define function ToString(value ContactPointUse): value.value
define function ToString(value ContractPublicationStatus): value.value
define function ToString(value ContractStatus): value.value
define function ToString(value ContributorType): value.value
define function ToString(value CoverageStatus): value.value
define function ToString(value CurrencyCode): value.value
define function ToString(value DayOfWeek): value.value
define function ToString(value DaysOfWeek): value.value
define function ToString(value DetectedIssueSeverity): value.value
define function ToString(value DetectedIssueStatus): value.value
define function ToString(value DeviceMetricCalibrationState): value.value
define function ToString(value DeviceMetricCalibrationType): value.value
define function ToString(value DeviceMetricCategory): value.value
define function ToString(value DeviceMetricColor): value.value
define function ToString(value DeviceMetricOperationalStatus): value.value
define function ToString(value DeviceNameType): value.value
define function ToString(value DeviceRequestStatus): value.value
define function ToString(value DeviceUseStatementStatus): value.value
define function ToString(value DiagnosticReportStatus): value.value
define function ToString(value DiscriminatorType): value.value
define function ToString(value DocumentConfidentiality): value.value
define function ToString(value DocumentMode): value.value
define function ToString(value DocumentReferenceStatus): value.value
define function ToString(value DocumentRelationshipType): value.value
define function ToString(value EligibilityRequestPurpose): value.value
define function ToString(value EligibilityRequestStatus): value.value
define function ToString(value EligibilityResponsePurpose): value.value
define function ToString(value EligibilityResponseStatus): value.value
define function ToString(value EnableWhenBehavior): value.value
define function ToString(value EncounterLocationStatus): value.value
define function ToString(value EncounterStatus): value.value
define function ToString(value EndpointStatus): value.value
define function ToString(value EnrollmentRequestStatus): value.value
define function ToString(value EnrollmentResponseStatus): value.value
define function ToString(value EpisodeOfCareStatus): value.value
define function ToString(value EventCapabilityMode): value.value
define function ToString(value EventTiming): value.value
define function ToString(value EvidenceVariableType): value.value
define function ToString(value ExampleScenarioActorType): value.value
define function ToString(value ExplanationOfBenefitStatus): value.value
define function ToString(value ExposureState): value.value
define function ToString(value ExtensionContextType): value.value
define function ToString(value FHIRAllTypes): value.value
define function ToString(value FHIRDefinedType): value.value
define function ToString(value FHIRDeviceStatus): value.value
define function ToString(value FHIRResourceType): value.value
define function ToString(value FHIRSubstanceStatus): value.value
define function ToString(value FHIRVersion): value.value
define function ToString(value FamilyHistoryStatus): value.value
define function ToString(value FilterOperator): value.value
define function ToString(value FlagStatus): value.value
define function ToString(value GoalLifecycleStatus): value.value
define function ToString(value GraphCompartmentRule): value.value
define function ToString(value GraphCompartmentUse): value.value
define function ToString(value GroupMeasure): value.value
define function ToString(value GroupType): value.value
define function ToString(value GuidanceResponseStatus): value.value
define function ToString(value GuidePageGeneration): value.value
define function ToString(value GuideParameterCode): value.value
define function ToString(value HTTPVerb): value.value
define function ToString(value IdentifierUse): value.value
define function ToString(value IdentityAssuranceLevel): value.value
define function ToString(value ImagingStudyStatus): value.value
define function ToString(value ImmunizationEvaluationStatus): value.value
define function ToString(value ImmunizationStatus): value.value
define function ToString(value InvoicePriceComponentType): value.value
define function ToString(value InvoiceStatus): value.value
define function ToString(value IssueSeverity): value.value
define function ToString(value IssueType): value.value
define function ToString(value LinkType): value.value
define function ToString(value LinkageType): value.value
define function ToString(value ListMode): value.value
define function ToString(value ListStatus): value.value
define function ToString(value LocationMode): value.value
define function ToString(value LocationStatus): value.value
define function ToString(value MeasureReportStatus): value.value
define function ToString(value MeasureReportType): value.value
define function ToString(value MediaStatus): value.value
define function ToString(value MedicationAdministrationStatus): value.value
define function ToString(value MedicationDispenseStatus): value.value
define function ToString(value MedicationKnowledgeStatus): value.value
define function ToString(value MedicationRequestIntent): value.value
define function ToString(value MedicationRequestPriority): value.value
define function ToString(value MedicationRequestStatus): value.value
define function ToString(value MedicationStatementStatus): value.value
define function ToString(value MedicationStatus): value.value
define function ToString(value MessageSignificanceCategory): value.value
define function ToString(value Messageheader_Response_Request): value.value
define function ToString(value MimeType): value.value
define function ToString(value NameUse): value.value
define function ToString(value NamingSystemIdentifierType): value.value
define function ToString(value NamingSystemType): value.value
define function ToString(value NarrativeStatus): value.value
define function ToString(value NoteType): value.value
define function ToString(value NutritiionOrderIntent): value.value
define function ToString(value NutritionOrderStatus): value.value
define function ToString(value ObservationDataType): value.value
define function ToString(value ObservationRangeCategory): value.value
define function ToString(value ObservationStatus): value.value
define function ToString(value OperationKind): value.value
define function ToString(value OperationParameterUse): value.value
define function ToString(value OrientationType): value.value
define function ToString(value ParameterUse): value.value
define function ToString(value ParticipantRequired): value.value
define function ToString(value ParticipantStatus): value.value
define function ToString(value ParticipationStatus): value.value
define function ToString(value PaymentNoticeStatus): value.value
define function ToString(value PaymentReconciliationStatus): value.value
define function ToString(value ProcedureStatus): value.value
define function ToString(value PropertyRepresentation): value.value
define function ToString(value PropertyType): value.value
define function ToString(value ProvenanceEntityRole): value.value
define function ToString(value PublicationStatus): value.value
define function ToString(value QualityType): value.value
define function ToString(value QuantityComparator): value.value
define function ToString(value QuestionnaireItemOperator): value.value
define function ToString(value QuestionnaireItemType): value.value
define function ToString(value QuestionnaireResponseStatus): value.value
define function ToString(value ReferenceHandlingPolicy): value.value
define function ToString(value ReferenceVersionRules): value.value
define function ToString(value ReferredDocumentStatus): value.value
define function ToString(value RelatedArtifactType): value.value
define function ToString(value RemittanceOutcome): value.value
define function ToString(value RepositoryType): value.value
define function ToString(value RequestIntent): value.value
define function ToString(value RequestPriority): value.value
define function ToString(value RequestStatus): value.value
define function ToString(value ResearchElementType): value.value
define function ToString(value ResearchStudyStatus): value.value
define function ToString(value ResearchSubjectStatus): value.value
define function ToString(value ResourceType): value.value
define function ToString(value ResourceVersionPolicy): value.value
define function ToString(value ResponseType): value.value
define function ToString(value RestfulCapabilityMode): value.value
define function ToString(value RiskAssessmentStatus): value.value
define function ToString(value SPDXLicense): value.value
define function ToString(value SearchComparator): value.value
define function ToString(value SearchEntryMode): value.value
define function ToString(value SearchModifierCode): value.value
define function ToString(value SearchParamType): value.value
define function ToString(value SectionMode): value.value
define function ToString(value SequenceType): value.value
define function ToString(value ServiceRequestIntent): value.value
define function ToString(value ServiceRequestPriority): value.value
define function ToString(value ServiceRequestStatus): value.value
define function ToString(value SlicingRules): value.value
define function ToString(value SlotStatus): value.value
define function ToString(value SortDirection): value.value
define function ToString(value SpecimenContainedPreference): value.value
define function ToString(value SpecimenStatus): value.value
define function ToString(value Status): value.value
define function ToString(value StrandType): value.value
define function ToString(value StructureDefinitionKind): value.value
define function ToString(value StructureMapContextType): value.value
define function ToString(value StructureMapGroupTypeMode): value.value
define function ToString(value StructureMapInputMode): value.value
define function ToString(value StructureMapModelMode): value.value
define function ToString(value StructureMapSourceListMode): value.value
define function ToString(value StructureMapTargetListMode): value.value
define function ToString(value StructureMapTransform): value.value
define function ToString(value SubscriptionChannelType): value.value
define function ToString(value SubscriptionStatus): value.value
define function ToString(value SupplyDeliveryStatus): value.value
define function ToString(value SupplyRequestStatus): value.value
define function ToString(value SystemRestfulInteraction): value.value
define function ToString(value TaskIntent): value.value
define function ToString(value TaskPriority): value.value
define function ToString(value TaskStatus): value.value
define function ToString(value TestReportActionResult): value.value
define function ToString(value TestReportParticipantType): value.value
define function ToString(value TestReportResult): value.value
define function ToString(value TestReportStatus): value.value
define function ToString(value TestScriptRequestMethodCode): value.value
define function ToString(value TriggerType): value.value
define function ToString(value TypeDerivationRule): value.value
define function ToString(value TypeRestfulInteraction): value.value
define function ToString(value UDIEntryType): value.value
define function ToString(value UnitsOfTime): value.value
define function ToString(value Use): value.value
define function ToString(value VariableType): value.value
define function ToString(value VisionBase): value.value
define function ToString(value VisionEyes): value.value
define function ToString(value VisionStatus): value.value
define function ToString(value XPathUsageType): value.value
define function ToString(value base64Binary): value.value
define function ToBoolean(value boolean): value.value
define function ToDate(value date): value.value
define function ToDateTime(value dateTime): value.value
define function ToDecimal(value decimal): value.value
define function ToDateTime(value instant): value.value
define function ToInteger(value integer): value.value
define function ToString(value string): value.value
define function ToTime(value time): value.value
define function ToString(value uri): value.value
define function ToString(value xhtml): value.value