From 7bb65025a21cab2835ee08b9f089fb2ad63b836a Mon Sep 17 00:00:00 2001
From: Achmad Setyabudi Susilo <anakinskywalk1@gmail.com>
Date: Sun, 28 Jun 2026 16:52:07 +0700
Subject: [PATCH] fix(#3): make ProcessDueRecurringExpenses atomic via
 withTransaction

Address review: insert + advance pair must run in one DB transaction to
prevent duplicate expenses if the process is killed mid-loop.
---
 .../dev/achmad/ledgerr/di/DomainModule.kt     |  2 +-
 .../interactor/ProcessDueRecurringExpenses.kt | 52 ++++++++++---------
 2 files changed, 28 insertions(+), 26 deletions(-)

diff --git a/app/src/main/java/dev/achmad/ledgerr/di/DomainModule.kt b/app/src/main/java/dev/achmad/ledgerr/di/DomainModule.kt
index 37af15b..35f8070 100644
--- a/app/src/main/java/dev/achmad/ledgerr/di/DomainModule.kt
+++ b/app/src/main/java/dev/achmad/ledgerr/di/DomainModule.kt
@@ -22,5 +22,5 @@ val domainModule = module {
     factory { GetRecurringExpenses(get()) }
     factory { UpsertRecurringExpense(get()) }
     factory { DeleteRecurringExpense(get()) }
-    factory { ProcessDueRecurringExpenses(get(), get()) }
+    factory { ProcessDueRecurringExpenses(get()) }
 }
diff --git a/app/src/main/java/dev/achmad/ledgerr/domain/recurring/interactor/ProcessDueRecurringExpenses.kt b/app/src/main/java/dev/achmad/ledgerr/domain/recurring/interactor/ProcessDueRecurringExpenses.kt
index b85c8aa..4a05ca2 100644
--- a/app/src/main/java/dev/achmad/ledgerr/domain/recurring/interactor/ProcessDueRecurringExpenses.kt
+++ b/app/src/main/java/dev/achmad/ledgerr/domain/recurring/interactor/ProcessDueRecurringExpenses.kt
@@ -1,36 +1,38 @@
 package dev.achmad.ledgerr.domain.recurring.interactor
 
-import dev.achmad.ledgerr.data.local.dao.ExpenseDao
-import dev.achmad.ledgerr.data.local.dao.RecurringExpenseDao
+import androidx.room.withTransaction
+import dev.achmad.ledgerr.data.local.AppDatabase
 import dev.achmad.ledgerr.data.local.mapper.toEntity
 import dev.achmad.ledgerr.data.local.mapper.toModel
 import dev.achmad.ledgerr.domain.expense.model.Expense
 import java.time.LocalDate
 
 class ProcessDueRecurringExpenses(
-    private val recurringDao: RecurringExpenseDao,
-    private val expenseDao: ExpenseDao,
+    private val database: AppDatabase,
 ) {
-    suspend fun await(today: LocalDate = LocalDate.now()): List<Expense> {
-        val dueTemplates = recurringDao.getDue(today.toEpochDay())
-        if (dueTemplates.isEmpty()) return emptyList()
-        val created = mutableListOf<Expense>()
-        for (templateEntity in dueTemplates) {
-            val template = templateEntity.toModel()
-            val expense = Expense(
-                amount = template.amount,
-                categoryId = template.categoryId,
-                date = template.nextDueDate,
-                note = template.note,
-                recurringExpenseId = template.id,
-            )
-            val newId = expenseDao.insert(expense.toEntity())
-            created += expense.copy(id = newId)
-            val advanced = template.copy(
-                nextDueDate = template.interval.advance(template.nextDueDate),
-            )
-            recurringDao.update(advanced.toEntity())
+    suspend fun await(today: LocalDate = LocalDate.now()): List<Expense> =
+        database.withTransaction {
+            val recurringDao = database.recurringExpenseDao()
+            val expenseDao = database.expenseDao()
+            val dueTemplates = recurringDao.getDue(today.toEpochDay())
+            if (dueTemplates.isEmpty()) return@withTransaction emptyList()
+            val created = mutableListOf<Expense>()
+            for (templateEntity in dueTemplates) {
+                val template = templateEntity.toModel()
+                val expense = Expense(
+                    amount = template.amount,
+                    categoryId = template.categoryId,
+                    date = template.nextDueDate,
+                    note = template.note,
+                    recurringExpenseId = template.id,
+                )
+                val newId = expenseDao.insert(expense.toEntity())
+                created += expense.copy(id = newId)
+                val advanced = template.copy(
+                    nextDueDate = template.interval.advance(template.nextDueDate),
+                )
+                recurringDao.update(advanced.toEntity())
+            }
+            created
         }
-        return created
-    }
 }