chore: abstract kotlin.time Instant implementation for tests

Signed-off-by: Brandon McAnsh <git@bmcreations.dev>

Author: bmc08gt

apps/flipcash/app/src/main/kotlin/com/flipcash/app/inject/TimeModule.kt

@@ -0,0 +1,18 @@
+package com.flipcash.app.inject
+
+import com.flipcash.app.core.time.TimeProvider
+import com.flipcash.app.internal.time.SystemTimeProvider
+import dagger.Module
+import dagger.Provides
+import dagger.hilt.InstallIn
+import dagger.hilt.components.SingletonComponent
+import javax.inject.Singleton
+
+@Module
+@InstallIn(SingletonComponent::class)
+object TimeModule {
+
+    @Provides
+    @Singleton
+    fun providesTimeProvider(): TimeProvider = SystemTimeProvider()
+}

apps/flipcash/app/src/main/kotlin/com/flipcash/app/internal/time/SystemTimeProvider.kt

@@ -0,0 +1,9 @@
+package com.flipcash.app.internal.time
+
+import com.flipcash.app.core.time.TimeProvider
+import kotlin.time.Clock
+
+class SystemTimeProvider : TimeProvider {
+    override fun now() = Clock.System.now()
+    override fun currentTimeMillis() = System.currentTimeMillis()
+}

apps/flipcash/core/src/main/kotlin/com/flipcash/app/core/time/FakeTimeProvider.kt

@@ -0,0 +1,13 @@
+package com.flipcash.app.core.time
+
+import kotlin.time.Clock
+import kotlin.time.Duration
+import kotlin.time.Instant
+
+class FakeTimeProvider(
+    private var currentTime: Instant = Clock.System.now()
+) : TimeProvider {
+    override fun now(): Instant = currentTime
+    fun advanceBy(duration: Duration) { currentTime += duration }
+    fun setTime(instant: Instant) { currentTime = instant }
+}

apps/flipcash/core/src/main/kotlin/com/flipcash/app/core/time/TimeProvider.kt

@@ -0,0 +1,8 @@
+package com.flipcash.app.core.time
+
+import kotlin.time.Instant
+
+interface TimeProvider {
+    fun now(): Instant
+    fun currentTimeMillis(): Long = now().toEpochMilliseconds()
+}