Use single queryDetailsForDevice if possible

To improve performance.

Since queryDetailsForDevice() also aggregated the uids into one,
the apps list in DataUsageList still needs another separated api call.

Fix: 315449973
Test: manual - on DataUsageList page
Test: unit tests
Change-Id: I96c23dd7d0d40ecd183e0fb0f61329db42dae1ab

src/com/android/settings/datausage/DataUsageListViewModel.kt

@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings.datausage
+
+import android.app.Application
+import android.net.NetworkTemplate
+import androidx.lifecycle.AndroidViewModel
+import androidx.lifecycle.viewModelScope
+import com.android.settings.datausage.lib.NetworkCycleBucketRepository
+import com.android.settings.datausage.lib.NetworkStatsRepository
+import com.android.settings.datausage.lib.NetworkStatsRepository.Companion.Bucket
+import com.android.settings.datausage.lib.NetworkStatsRepository.Companion.filterTime
+import com.android.settings.datausage.lib.NetworkUsageData
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.SharingStarted
+import kotlinx.coroutines.flow.combine
+import kotlinx.coroutines.flow.filterNotNull
+import kotlinx.coroutines.flow.flowOn
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.flow.stateIn
+import kotlinx.coroutines.plus
+
+data class SelectedBuckets(
+    val selectedCycle: NetworkUsageData,
+    val buckets: List<Bucket>,
+)
+
+class DataUsageListViewModel(application: Application) : AndroidViewModel(application) {
+    private val scope = viewModelScope + Dispatchers.Default
+
+    val templateFlow = MutableStateFlow<NetworkTemplate?>(null)
+
+    private val bucketsFlow = templateFlow.filterNotNull().map { template ->
+        NetworkStatsRepository(getApplication(), template).queryDetailsForDevice()
+    }.stateIn(scope, SharingStarted.WhileSubscribed(), emptyList())
+
+    val cyclesFlow = combine(templateFlow.filterNotNull(), bucketsFlow) { template, buckets ->
+        NetworkCycleBucketRepository(application, template, buckets).loadCycles()
+    }.flowOn(Dispatchers.Default)
+
+    val selectedCycleFlow = MutableStateFlow<NetworkUsageData?>(null)
+
+    private val selectedBucketsFlow =
+        combine(selectedCycleFlow.filterNotNull(), bucketsFlow) { selectedCycle, buckets ->
+            SelectedBuckets(
+                selectedCycle = selectedCycle,
+                buckets = buckets.filterTime(selectedCycle.startTime, selectedCycle.endTime),
+            )
+        }.flowOn(Dispatchers.Default)
+
+    val chartDataFlow =
+        combine(templateFlow.filterNotNull(), selectedBucketsFlow) { template, selectedBuckets ->
+            NetworkCycleBucketRepository(application, template, selectedBuckets.buckets)
+                .queryChartData(selectedBuckets.selectedCycle)
+        }.flowOn(Dispatchers.Default)
+}