Allow multiple resources to be set in context (#2000)

* allow multiple resources to be set in context

* rename builder api

* address comments

* restore pairing

* simplify logic

* add test case with multiple and address comments

datacapture/src/main/java/com/google/android/fhir/datacapture/QuestionnaireFragment.kt

@@ -303,8 +303,16 @@ class QuestionnaireFragment : Fragment() {
       args.add(EXTRA_QUESTIONNAIRE_RESPONSE_JSON_URI to questionnaireResponseUri)
     }
 
-    fun setQuestionnaireLaunchContext(questionnaireLaunchContext: String) = apply {
-      args.add(EXTRA_QUESTIONNAIRE_LAUNCH_CONTEXT_JSON_STRING to questionnaireLaunchContext)
+    /**
+     * The launch context allows information to be passed into questionnaire based on the context in
+     * which the questionnaire is being evaluated. For example, what patient, what encounter, what
+     * user, etc. is "in context" at the time the questionnaire response is being completed:
+     * https://build.fhir.org/ig/HL7/sdc/StructureDefinition-sdc-questionnaire-launchContext.html
+     *
+     * @param launchContexts list of serialized resources
+     */
+    fun setQuestionnaireLaunchContexts(launchContexts: List<String>) = apply {
+      args.add(EXTRA_QUESTIONNAIRE_LAUNCH_CONTEXT_JSON_STRINGS to launchContexts)
     }
 
     /**
@@ -398,9 +406,9 @@ class QuestionnaireFragment : Fragment() {
      */
     internal const val EXTRA_QUESTIONNAIRE_RESPONSE_JSON_STRING = "questionnaire-response"
 
-    /** A JSON encoded string extra for questionnaire context. */
-    internal const val EXTRA_QUESTIONNAIRE_LAUNCH_CONTEXT_JSON_STRING =
-      "questionnaire-launch-context"
+    /** A list of JSON encoded strings extra for each questionnaire context. */
+    internal const val EXTRA_QUESTIONNAIRE_LAUNCH_CONTEXT_JSON_STRINGS =
+      "questionnaire-launch-contexts"
     /**
      * A [URI][android.net.Uri] extra for streaming a JSON encoded questionnaire response.
      *

datacapture/src/main/java/com/google/android/fhir/datacapture/QuestionnaireViewModel.kt

@@ -26,7 +26,6 @@ import ca.uhn.fhir.context.FhirContext
 import ca.uhn.fhir.context.FhirVersionEnum
 import ca.uhn.fhir.parser.IParser
 import com.google.android.fhir.datacapture.enablement.EnablementEvaluator
-import com.google.android.fhir.datacapture.extensions.EXTENSION_SDC_QUESTIONNAIRE_LAUNCH_CONTEXT
 import com.google.android.fhir.datacapture.extensions.EntryMode
 import com.google.android.fhir.datacapture.extensions.addNestedItemsToAnswer
 import com.google.android.fhir.datacapture.extensions.allItems
@@ -44,9 +43,10 @@ import com.google.android.fhir.datacapture.extensions.isPaginated
 import com.google.android.fhir.datacapture.extensions.isXFhirQuery
 import com.google.android.fhir.datacapture.extensions.localizedTextSpanned
 import com.google.android.fhir.datacapture.extensions.packRepeatedGroups
+import com.google.android.fhir.datacapture.extensions.questionnaireLaunchContexts
 import com.google.android.fhir.datacapture.extensions.shouldHaveNestedItemsUnderAnswers
 import com.google.android.fhir.datacapture.extensions.unpackRepeatedGroups
-import com.google.android.fhir.datacapture.extensions.validateLaunchContext
+import com.google.android.fhir.datacapture.extensions.validateLaunchContextExtensions
 import com.google.android.fhir.datacapture.extensions.zipByLinkId
 import com.google.android.fhir.datacapture.fhirpath.ExpressionEvaluator
 import com.google.android.fhir.datacapture.fhirpath.ExpressionEvaluator.detectExpressionCyclicDependency
@@ -160,25 +160,24 @@ internal class QuestionnaireViewModel(application: Application, state: SavedStat
 
   /**
    * The launch context allows information to be passed into questionnaire based on the context in
-   * which he questionnaire is being evaluated. For example, what patient, what encounter, what
-   * user, etc. is "in context" at the time the questionnaire response is being completed.
-   * Currently, we support at most one launch context.The supported launch contexts are defined in:
+   * which the questionnaire is being evaluated. For example, what patient, what encounter, what
+   * user, etc. is "in context" at the time the questionnaire response is being completed:
    * https://build.fhir.org/ig/HL7/sdc/StructureDefinition-sdc-questionnaire-launchContext.html
    */
-  private val questionnaireLaunchContext: Resource?
+  private val questionnaireLaunchContextMap: Map<String, Resource>?
 
   init {
-    questionnaireLaunchContext =
-      if (state.contains(QuestionnaireFragment.EXTRA_QUESTIONNAIRE_LAUNCH_CONTEXT_JSON_STRING)) {
-        val questionnaireLaunchContextJson: String =
-          state[QuestionnaireFragment.EXTRA_QUESTIONNAIRE_LAUNCH_CONTEXT_JSON_STRING]!!
-        questionnaire.extension
-          .firstOrNull { it.url == EXTENSION_SDC_QUESTIONNAIRE_LAUNCH_CONTEXT }
-          ?.let {
-            val resource = parser.parseResource(questionnaireLaunchContextJson) as Resource
-            validateLaunchContext(it, resource.resourceType.name)
-            resource
-          }
+    questionnaireLaunchContextMap =
+      if (state.contains(QuestionnaireFragment.EXTRA_QUESTIONNAIRE_LAUNCH_CONTEXT_JSON_STRINGS)) {
+
+        val launchContextJsonStrings: List<String> =
+          state[QuestionnaireFragment.EXTRA_QUESTIONNAIRE_LAUNCH_CONTEXT_JSON_STRINGS]!!
+
+        val launchContexts = launchContextJsonStrings.map { parser.parseResource(it) as Resource }
+        questionnaire.questionnaireLaunchContexts?.let { launchContextExtensions ->
+          validateLaunchContextExtensions(launchContextExtensions)
+          launchContexts.associateBy { it.resourceType.name.lowercase() }
+        }
       } else {
         null
       }
@@ -584,7 +583,10 @@ internal class QuestionnaireViewModel(application: Application, state: SavedStat
         }
 
         val xFhirExpressionString =
-          ExpressionEvaluator.createXFhirQueryFromExpression(expression, questionnaireLaunchContext)
+          ExpressionEvaluator.createXFhirQueryFromExpression(
+            expression,
+            questionnaireLaunchContextMap
+          )
         xFhirQueryResolver!!.resolve(xFhirExpressionString)
       } else if (expression.isFhirPath) {
         fhirPathEngine.evaluate(questionnaireResponse, expression.expression)

datacapture/src/main/java/com/google/android/fhir/datacapture/extensions/MoreQuestionnaires.kt

@@ -17,6 +17,7 @@
 package com.google.android.fhir.datacapture.extensions
 
 import org.hl7.fhir.r4.model.CanonicalType
+import org.hl7.fhir.r4.model.CodeType
 import org.hl7.fhir.r4.model.Coding
 import org.hl7.fhir.r4.model.Expression
 import org.hl7.fhir.r4.model.Extension
@@ -38,6 +39,16 @@ internal val Questionnaire.variableExpressions: List<Expression>
   get() =
     this.extension.filter { it.url == EXTENSION_VARIABLE_URL }.map { it.castToExpression(it.value) }
 
+/**
+ * A list of extensions that define the resources that provide context for form processing logic:
+ * https://build.fhir.org/ig/HL7/sdc/StructureDefinition-sdc-questionnaire-launchContext.html
+ */
+internal val Questionnaire.questionnaireLaunchContexts: List<Extension>?
+  get() =
+    this.extension
+      .filter { it.url == EXTENSION_SDC_QUESTIONNAIRE_LAUNCH_CONTEXT }
+      .takeIf { it.isNotEmpty() }
+
 /**
  * Finds the specific variable name [String] at questionnaire [Questionnaire] level
  *
@@ -48,38 +59,57 @@ internal fun Questionnaire.findVariableExpression(variableName: String): Express
   variableExpressions.find { it.name == variableName }
 
 /**
- * Validates the questionnaire launch context extension, if it exists, and well formed, and
- * validates if the resource type is applicable as a launch context.
+ * Validates each questionnaire launch context extension matches:
+ * https://build.fhir.org/ig/HL7/sdc/StructureDefinition-sdc-questionnaire-launchContext.html
  */
-internal fun validateLaunchContext(extension: Extension, resourceType: String) {
-  val nameExtension =
-    extension.extension
-      .firstOrNull { it.url == "name" }
-      ?.value.takeIf { type ->
-        type is Coding &&
-          QuestionnaireLaunchContextSet.values().any {
-            it.code == type.code && it.display == type.display && it.system == type.system
-          }
+internal fun validateLaunchContextExtensions(launchContextExtensions: List<Extension>) =
+  launchContextExtensions.forEach { launchExtension ->
+    validateLaunchContextExtension(
+      Extension().apply {
+        addExtension(launchExtension.extension.firstOrNull { it.url == "name" })
+        addExtension(launchExtension.extension.firstOrNull { it.url == "type" })
       }
-
-  val typeExtension =
-    extension.extension
-      .firstOrNull { it.url == "type" }
-      ?.takeIf { it.valueAsPrimitive.valueAsString == resourceType }
-
-  if (nameExtension == null) {
-    error(
-      "The value of the extension:name field in " +
-        "$EXTENSION_SDC_QUESTIONNAIRE_LAUNCH_CONTEXT is not one of the ones defined in " +
-        "$EXTENSION_LAUNCH_CONTEXT."
     )
   }
 
-  if (typeExtension == null) {
+/**
+ * Checks that the extension:name extension exists and its value contains a valid code from
+ * [QuestionnaireLaunchContextSet]
+ */
+private fun validateLaunchContextExtension(launchExtension: Extension) {
+  check(launchExtension.extension.size == 2) {
+    "The extension:name or extension:type extension is missing in $EXTENSION_SDC_QUESTIONNAIRE_LAUNCH_CONTEXT"
+  }
+
+  val isValidExtension =
+    QuestionnaireLaunchContextSet.values().any {
+      launchExtension.equalsDeep(
+        Extension().apply {
+          addExtension(
+            Extension().apply {
+              url = "name"
+              setValue(
+                Coding().apply {
+                  code = it.code
+                  display = it.display
+                  system = it.system
+                }
+              )
+            }
+          )
+          addExtension(
+            Extension().apply {
+              url = "type"
+              setValue(CodeType().setValue(it.resourceType))
+            }
+          )
+        }
+      )
+    }
+  if (!isValidExtension) {
     error(
-      "The resource type set in the extension:type field in " +
-        "$EXTENSION_SDC_QUESTIONNAIRE_LAUNCH_CONTEXT does not match the resource type of the " +
-        "context passed in: $resourceType."
+      "The extension:name extension and/or extension:type extension do not follow the format " +
+        "specified in $EXTENSION_SDC_QUESTIONNAIRE_LAUNCH_CONTEXT"
     )
   }
 }
@@ -91,12 +121,16 @@ private enum class QuestionnaireLaunchContextSet(
   val code: String,
   val display: String,
   val system: String,
+  val resourceType: String,
 ) {
-  PATIENT("patient", "Patient", EXTENSION_LAUNCH_CONTEXT),
-  ENCOUNTER("encounter", "Encounter", EXTENSION_LAUNCH_CONTEXT),
-  LOCATION("location", "Location", EXTENSION_LAUNCH_CONTEXT),
-  USER("user", "User", EXTENSION_LAUNCH_CONTEXT),
-  STUDY("study", "ResearchStudy", EXTENSION_LAUNCH_CONTEXT),
+  PATIENT("patient", "Patient", EXTENSION_LAUNCH_CONTEXT, "Patient"),
+  ENCOUNTER("encounter", "Encounter", EXTENSION_LAUNCH_CONTEXT, "Encounter"),
+  LOCATION("location", "Location", EXTENSION_LAUNCH_CONTEXT, "Location"),
+  USER_AS_PATIENT("user", "User", EXTENSION_LAUNCH_CONTEXT, "Patient"),
+  USER_AS_PRACTITIONER("user", "User", EXTENSION_LAUNCH_CONTEXT, "Practitioner"),
+  USER_AS_PRACTITIONER_ROLE("user", "User", EXTENSION_LAUNCH_CONTEXT, "PractitionerRole"),
+  USER_AS_RELATED_PERSON("user", "User", EXTENSION_LAUNCH_CONTEXT, "RelatedPerson"),
+  STUDY("study", "ResearchStudy", EXTENSION_LAUNCH_CONTEXT, "ResearchStudy"),
 }
 
 /**

datacapture/src/main/java/com/google/android/fhir/datacapture/fhirpath/ExpressionEvaluator.kt

@@ -282,16 +282,16 @@ object ExpressionEvaluator {
    * Creates an x-fhir-query string for evaluation
    *
    * @param expression x-fhir-query expression
-   * @param launchContext if passed, the launch context to evaluate the expression against
+   * @param launchContextMap if passed, the launch context to evaluate the expression against
    */
   internal fun createXFhirQueryFromExpression(
     expression: Expression,
-    launchContext: Resource?
+    launchContextMap: Map<String, Resource>?
   ): String {
-    if (launchContext == null) {
+    if (launchContextMap == null) {
       return expression.expression
     }
-    return evaluateXFhirEnhancement(expression, launchContext).fold(expression.expression) {
+    return evaluateXFhirEnhancement(expression, launchContextMap).fold(expression.expression) {
       acc: String,
       pair: Pair<String, String> ->
       acc.replace(pair.first, pair.second)
@@ -305,11 +305,11 @@ object ExpressionEvaluator {
    *
    * @param expression x-fhir-query expression containing a FHIRpath, e.g.
    * Practitioner?active=true&{{Practitioner.name.family}}
-   * @param resource the launch context to evaluate the expression against
+   * @param launchContextMap the launch context to evaluate the expression against
    */
   private fun evaluateXFhirEnhancement(
     expression: Expression,
-    resource: Resource
+    launchContextMap: Map<String, Resource>
   ): Sequence<Pair<String, String>> =
     xFhirQueryEnhancementRegex
       .findAll(expression.expression)
@@ -318,12 +318,15 @@ object ExpressionEvaluator {
         // TODO(omarismail94): See if FHIRPathEngine.check() can be used to distinguish invalid
         // expression vs an expression that is valid, but does not return one resource only.
         val expressionNode = fhirPathEngine.parse(fhirPath)
+        val resourceType =
+          expressionNode.constant?.primitiveValue()?.substring(1)
+            ?: expressionNode.name?.lowercase()
         val evaluatedResult =
           fhirPathEngine.evaluateToString(
-            mapOf(resource.resourceType.name.lowercase() to resource),
+            launchContextMap,
             null,
             null,
-            resource,
+            launchContextMap[resourceType],
             expressionNode
           )
 

datacapture/src/test/java/com/google/android/fhir/datacapture/QuestionnaireViewModelTest.kt

@@ -27,7 +27,7 @@ import com.google.android.fhir.FhirEngine
 import com.google.android.fhir.FhirEngineProvider
 import com.google.android.fhir.datacapture.QuestionnaireFragment.Companion.EXTRA_ENABLE_REVIEW_PAGE
 import com.google.android.fhir.datacapture.QuestionnaireFragment.Companion.EXTRA_QUESTIONNAIRE_JSON_STRING
-import com.google.android.fhir.datacapture.QuestionnaireFragment.Companion.EXTRA_QUESTIONNAIRE_LAUNCH_CONTEXT_JSON_STRING
+import com.google.android.fhir.datacapture.QuestionnaireFragment.Companion.EXTRA_QUESTIONNAIRE_LAUNCH_CONTEXT_JSON_STRINGS
 import com.google.android.fhir.datacapture.QuestionnaireFragment.Companion.EXTRA_QUESTIONNAIRE_RESPONSE_JSON_STRING
 import com.google.android.fhir.datacapture.QuestionnaireFragment.Companion.EXTRA_READ_ONLY
 import com.google.android.fhir.datacapture.QuestionnaireFragment.Companion.EXTRA_SHOW_REVIEW_PAGE_FIRST
@@ -86,7 +86,6 @@ import org.hl7.fhir.r4.model.Practitioner
 import org.hl7.fhir.r4.model.Quantity
 import org.hl7.fhir.r4.model.Questionnaire
 import org.hl7.fhir.r4.model.QuestionnaireResponse
-import org.hl7.fhir.r4.model.QuestionnaireResponse.QuestionnaireResponseItemComponent
 import org.hl7.fhir.r4.model.StringType
 import org.hl7.fhir.r4.model.ValueSet
 import org.hl7.fhir.r4.utils.ToolingExtensions
@@ -3921,13 +3920,7 @@ class QuestionnaireViewModelTest {
         )
 
       val patientId = "123"
-      val patient =
-        Patient().apply {
-          id = patientId
-          active = true
-          gender = Enumerations.AdministrativeGender.MALE
-          addName(HumanName().apply { this.family = "Johnny" })
-        }
+      val patient = Patient().apply { id = patientId }
 
       val questionnaire =
         Questionnaire().apply {
@@ -3968,8 +3961,8 @@ class QuestionnaireViewModelTest {
         }
       state.set(EXTRA_QUESTIONNAIRE_JSON_STRING, printer.encodeResourceToString(questionnaire))
       state.set(
-        EXTRA_QUESTIONNAIRE_LAUNCH_CONTEXT_JSON_STRING,
-        printer.encodeResourceToString(patient)
+        EXTRA_QUESTIONNAIRE_LAUNCH_CONTEXT_JSON_STRINGS,
+        listOf(printer.encodeResourceToString(patient))
       )
 
       val viewModel = QuestionnaireViewModel(context, state)