Extract mapping of SortDirection to Firestore direction to extension function

Author: EdricChan03

data/common/src/main/kotlin/com/edricchan/studybuddy/domain/common/sorting/OrderSpec.kt

@@ -1,5 +1,7 @@
 package com.edricchan.studybuddy.domain.common.sorting
 
+import com.google.firebase.firestore.Query
+
 /**
  * Specification for a specific field to order a list of data by.
  * @property field Desired field to order the data by.
@@ -18,3 +20,9 @@ enum class SortDirection {
     /** Sort the resulting data in ascending order, i.e. smallest to largest. */
     Ascending
 }
+
+/** Converts the receiver [SortDirection] to its Firebase [Query.Direction] equivalent. */
+fun SortDirection.toFirestoreDirection(): Query.Direction = when (this) {
+    SortDirection.Descending -> Query.Direction.DESCENDING
+    SortDirection.Ascending -> Query.Direction.ASCENDING
+}

features/tasks/data/src/main/kotlin/com/edricchan/studybuddy/features/tasks/data/repo/TaskRepository.kt

@@ -9,7 +9,7 @@ import androidx.paging.map
 import com.edricchan.studybuddy.data.common.QueryMapper
 import com.edricchan.studybuddy.data.paging.firestore.firestorePagingSource
 import com.edricchan.studybuddy.data.source.firestore.IDefaultFirestoreDataSource
-import com.edricchan.studybuddy.domain.common.sorting.SortDirection
+import com.edricchan.studybuddy.domain.common.sorting.toFirestoreDirection
 import com.edricchan.studybuddy.features.tasks.data.mapper.toDomain
 import com.edricchan.studybuddy.features.tasks.data.mapper.toDto
 import com.edricchan.studybuddy.features.tasks.data.model.TodoItem
@@ -18,7 +18,6 @@ import com.edricchan.studybuddy.features.tasks.domain.model.TaskItem
 import com.edricchan.studybuddy.features.tasks.domain.repo.ITaskRepository
 import com.edricchan.studybuddy.features.tasks.domain.repo.TasksPaginationConfig
 import com.google.firebase.firestore.DocumentReference
-import com.google.firebase.firestore.Query
 import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.combine
@@ -120,11 +119,7 @@ class TaskRepository @Inject constructor(
             ) else it
         }.let {
             config.orderByFields.fold(it) { query, spec ->
-                val direction = when (spec.direction) {
-                    SortDirection.Descending -> Query.Direction.DESCENDING
-                    SortDirection.Ascending -> Query.Direction.ASCENDING
-                }
-                query.orderBy(spec.field.toDto().fieldName, direction)
+                query.orderBy(spec.field.toDto().fieldName, spec.direction.toFirestoreDirection())
             }
         }