Experiment with stashing

app/src/main/java/com/aurora/store/Aliases.kt

@@ -0,0 +1,9 @@
+package com.aurora.store
+
+import com.aurora.gplayapi.data.models.StreamBundle
+import com.aurora.gplayapi.data.models.StreamCluster
+import com.aurora.gplayapi.helpers.contracts.StreamContract
+import com.aurora.gplayapi.helpers.contracts.TopChartsContract
+
+typealias TopChartStash = Map<TopChartsContract.Type, Map<TopChartsContract.Chart, StreamCluster>>
+typealias HomeStash = MutableMap<StreamContract.Category, StreamBundle>

app/src/main/java/com/aurora/store/data/model/State.kt

@@ -21,6 +21,10 @@ package com.aurora.store.data.model
 
 
 sealed class ViewState {
+    inline fun <reified T> ViewState.getDataAs(): T {
+        return (this as? Success<*>)?.data as T
+    }
+
     data object Loading : ViewState()
     data object Empty : ViewState()
     data class Error(val error: String?) : ViewState()
@@ -34,7 +38,7 @@ sealed class AuthState {
     data object SignedIn : AuthState()
     data object SignedOut : AuthState()
     data object Valid : AuthState()
-    data object Fetching: AuthState()
+    data object Fetching : AuthState()
-    data object Verifying: AuthState()
+    data object Verifying : AuthState()
     data class Failed(val status: String) : AuthState()
 }

app/src/main/java/com/aurora/store/view/ui/commons/ForYouFragment.kt

@@ -28,8 +28,10 @@ import com.aurora.gplayapi.data.models.StreamBundle
 import com.aurora.gplayapi.data.models.StreamCluster
 import com.aurora.gplayapi.helpers.contracts.StreamContract.Category
 import com.aurora.gplayapi.helpers.contracts.StreamContract.Type
+import com.aurora.store.HomeStash
 import com.aurora.store.R
 import com.aurora.store.data.model.ViewState
+import com.aurora.store.data.ViewState.Loading.getDataAs
 import com.aurora.store.databinding.FragmentForYouBinding
 import com.aurora.store.view.custom.recycler.EndlessRecyclerOnScrollListener
 import com.aurora.store.view.epoxy.controller.GenericCarouselController
@@ -43,10 +45,10 @@ class ForYouFragment : BaseFragment(R.layout.fragment_for_you),
     private var _binding: FragmentForYouBinding? = null
     private val binding get() = _binding!!
 
-    private var category: Category = Category.APPLICATION
     private val viewModel: StreamViewModel by activityViewModels()
 
-    private lateinit var streamBundle: StreamBundle
+    private var category: Category = Category.APPLICATION
+    private var streamBundle: StreamBundle? = StreamBundle()
 
     companion object {
         @JvmStatic
@@ -84,6 +86,13 @@ class ForYouFragment : BaseFragment(R.layout.fragment_for_you),
         }
 
         binding.recycler.setController(genericCarouselController)
+        binding.recycler.addOnScrollListener(
+            object : EndlessRecyclerOnScrollListener() {
+                override fun onLoadMore(currentPage: Int) {
+                    viewModel.observe(category, Type.HOME)
+                }
+            }
+        )
 
         viewModel.liveData.observe(viewLifecycleOwner) {
             when (it) {
@@ -92,17 +101,9 @@ class ForYouFragment : BaseFragment(R.layout.fragment_for_you),
                 }
 
                 is ViewState.Success<*> -> {
-                    if (!::streamBundle.isInitialized) {
+                    val stash = it.getDataAs<HomeStash>()
-                        binding.recycler.addOnScrollListener(
+                    streamBundle = stash[category]
-                            object : EndlessRecyclerOnScrollListener() {
-                                override fun onLoadMore(currentPage: Int) {
-                                    viewModel.observe(category, Type.HOME)
-                                }
-                            }
-                        )
-                    }
 
-                    streamBundle = it.data as StreamBundle
                     genericCarouselController.setData(streamBundle)
                 }
 

app/src/main/java/com/aurora/store/view/ui/commons/TopChartFragment.kt

@@ -21,12 +21,15 @@ package com.aurora.store.view.ui.commons
 
 import android.os.Bundle
 import android.view.View
-import androidx.fragment.app.viewModels
+import androidx.fragment.app.activityViewModels
 import com.aurora.Constants
 import com.aurora.gplayapi.data.models.StreamCluster
 import com.aurora.gplayapi.helpers.contracts.TopChartsContract.Chart
 import com.aurora.gplayapi.helpers.contracts.TopChartsContract.Type
 import com.aurora.store.R
+import com.aurora.store.TopChartStash
+import com.aurora.store.data.ViewState
+import com.aurora.store.data.ViewState.Empty.getDataAs
 import com.aurora.store.databinding.FragmentTopContainerBinding
 import com.aurora.store.view.custom.recycler.EndlessRecyclerOnScrollListener
 import com.aurora.store.view.epoxy.views.AppProgressViewModel_
@@ -41,7 +44,9 @@ class TopChartFragment : BaseFragment(R.layout.fragment_top_container) {
     private var _binding: FragmentTopContainerBinding? = null
     private val binding get() = _binding!!
 
-    private val viewModel: TopChartViewModel by viewModels()
+    private val viewModel: TopChartViewModel by activityViewModels()
+
+    private var streamCluster: StreamCluster? = StreamCluster()
 
     companion object {
         @JvmStatic
@@ -59,42 +64,52 @@ class TopChartFragment : BaseFragment(R.layout.fragment_top_container) {
         super.onViewCreated(view, savedInstanceState)
         _binding = FragmentTopContainerBinding.bind(view)
 
-        var chartType = 0
+        var type = 0
-        var chartCategory = 0
+        var category = 0
         val bundle = arguments
 
         if (bundle != null) {
-            chartType = bundle.getInt(Constants.TOP_CHART_TYPE, 0)
+            type = bundle.getInt(Constants.TOP_CHART_TYPE, 0)
-            chartCategory = bundle.getInt(Constants.TOP_CHART_CATEGORY, 0)
+            category = bundle.getInt(Constants.TOP_CHART_CATEGORY, 0)
         }
 
-        when (chartType) {
+        val chartType = when (type) {
-            0 -> when (chartCategory) {
+            1 -> Type.GAME
-                0 -> viewModel.getStreamCluster(Type.APPLICATION, Chart.TOP_SELLING_FREE)
+            else -> Type.APPLICATION
-                1 -> viewModel.getStreamCluster(Type.APPLICATION, Chart.TOP_GROSSING)
-                2 -> viewModel.getStreamCluster(Type.APPLICATION, Chart.MOVERS_SHAKERS)
-                3 -> viewModel.getStreamCluster(Type.APPLICATION, Chart.TOP_SELLING_PAID)
-            }
-
-            1 -> when (chartCategory) {
-                0 -> viewModel.getStreamCluster(Type.GAME, Chart.TOP_SELLING_FREE)
-                1 -> viewModel.getStreamCluster(Type.GAME, Chart.TOP_GROSSING)
-                2 -> viewModel.getStreamCluster(Type.GAME, Chart.MOVERS_SHAKERS)
-                3 -> viewModel.getStreamCluster(Type.GAME, Chart.TOP_SELLING_PAID)
-            }
         }
 
-        viewModel.liveData.observe(viewLifecycleOwner) {
+        val chartCategory = when (category) {
-            updateController(it)
+            1 -> Chart.TOP_GROSSING
+            2 -> Chart.MOVERS_SHAKERS
+            3 -> Chart.TOP_SELLING_PAID
+            else -> Chart.TOP_SELLING_FREE
         }
 
         binding.recycler.addOnScrollListener(object : EndlessRecyclerOnScrollListener() {
             override fun onLoadMore(currentPage: Int) {
-                viewModel.nextCluster()
+                viewModel.nextCluster(chartType, chartCategory)
             }
         })
 
         updateController(null)
+
+        viewModel.getStreamCluster(chartType, chartCategory)
+        viewModel.liveData.observe(viewLifecycleOwner) {
+            when (it) {
+                is ViewState.Loading, is ViewState.Error -> {
+                    updateController(null)
+                }
+
+                is ViewState.Success<*> -> {
+                    val stash = it.getDataAs<TopChartStash>()
+                    streamCluster = stash[chartType]?.get(chartCategory)
+
+                    updateController(streamCluster)
+                }
+
+                else -> {}
+            }
+        }
     }
 
     override fun onDestroyView() {

app/src/main/java/com/aurora/store/viewmodel/homestream/StreamViewModel.kt

@@ -30,6 +30,7 @@ import com.aurora.gplayapi.helpers.StreamHelper
 import com.aurora.store.data.model.ViewState
 import com.aurora.gplayapi.helpers.contracts.StreamContract
 import com.aurora.gplayapi.helpers.web.WebStreamHelper
+import com.aurora.store.HomeStash
 import com.aurora.store.data.network.HttpClient
 import com.aurora.store.data.providers.AuthProvider
 import com.aurora.store.util.Log
@@ -55,7 +56,7 @@ class StreamViewModel @Inject constructor(
 
     val liveData: MutableLiveData<ViewState> = MutableLiveData()
 
-    private var streamBundleMap: MutableMap<StreamContract.Category, StreamBundle> = mutableMapOf(
+    private var stash: HomeStash = mutableMapOf(
         StreamContract.Category.APPLICATION to StreamBundle(),
         StreamContract.Category.GAME to StreamBundle()
     )
@@ -77,7 +78,7 @@ class StreamViewModel @Inject constructor(
         viewModelScope.launch(Dispatchers.IO) {
             supervisorScope {
                 if (targetBundle(category).streamClusters.isNotEmpty()) {
-                    liveData.postValue(ViewState.Success(targetBundle(category)))
+                    liveData.postValue(ViewState.Success(stash))
                 }
 
                 try {
@@ -100,7 +101,7 @@ class StreamViewModel @Inject constructor(
                         }
 
                         //Post updated to UI
-                        liveData.postValue(ViewState.Success(targetBundle(category)))
+                        liveData.postValue(ViewState.Success(stash))
                     } else {
                         Log.i("End of Bundle")
                     }
@@ -119,7 +120,7 @@ class StreamViewModel @Inject constructor(
                         val newCluster =
                             contract().nextStreamCluster(streamCluster.clusterNextPageUrl)
                         updateCluster(category, streamCluster.id, newCluster)
-                        liveData.postValue(ViewState.Success(targetBundle(category)))
+                        liveData.postValue(ViewState.Success(stash))
                     } else {
                         Log.i("End of cluster")
                         streamCluster.clusterNextPageUrl = String()
@@ -143,8 +144,9 @@ class StreamViewModel @Inject constructor(
     }
 
     private fun targetBundle(category: StreamContract.Category): StreamBundle {
-        val streamBundle = streamBundleMap[category]
+        // stash is initialized with empty StreamBundle so this will never return null or throw an exception
+        val streamBundle = stash.getValue(category)
 
-        return streamBundle!!
+        return streamBundle
     }
 }

app/src/main/java/com/aurora/store/viewmodel/topchart/TopChartViewModel.kt

@@ -28,6 +28,8 @@ import com.aurora.gplayapi.data.models.StreamCluster
 import com.aurora.gplayapi.helpers.TopChartsHelper
 import com.aurora.gplayapi.helpers.contracts.TopChartsContract
 import com.aurora.gplayapi.helpers.web.WebTopChartsHelper
+import com.aurora.store.TopChartStash
+import com.aurora.store.data.ViewState
 import com.aurora.store.data.network.HttpClient
 import com.aurora.store.data.providers.AuthProvider
 import dagger.hilt.android.lifecycle.HiltViewModel
@@ -50,11 +52,22 @@ class TopChartViewModel @Inject constructor(
     private val webTopChartsHelper: TopChartsContract = WebTopChartsHelper()
         .using(HttpClient.getPreferredClient(context))
 
-    val liveData: MutableLiveData<StreamCluster> = MutableLiveData()
+    private val dummyChart = mapOf(
-    var streamCluster: StreamCluster = StreamCluster()
+        TopChartsContract.Chart.TOP_GROSSING to StreamCluster(),
+        TopChartsContract.Chart.TOP_SELLING_FREE to StreamCluster(),
+        TopChartsContract.Chart.TOP_SELLING_PAID to StreamCluster(),
+        TopChartsContract.Chart.MOVERS_SHAKERS to StreamCluster(),
+    )
+
+    private var stash: TopChartStash = mapOf(
+        TopChartsContract.Type.APPLICATION to dummyChart,
+        TopChartsContract.Type.GAME to dummyChart
+    )
+
+    val liveData: MutableLiveData<ViewState> = MutableLiveData()
 
     private fun contract(): TopChartsContract {
-        return if(authProvider.isAnonymous){
+        return if (authProvider.isAnonymous) {
             webTopChartsHelper
         } else {
             topChartsHelper
@@ -63,34 +76,56 @@ class TopChartViewModel @Inject constructor(
 
     fun getStreamCluster(type: TopChartsContract.Type, chart: TopChartsContract.Chart) {
         viewModelScope.launch(Dispatchers.IO) {
+            if (targetCluster(type, chart).clusterAppList.isNotEmpty()) {
+                liveData.postValue(ViewState.Success(stash))
+            }
+
             try {
-                streamCluster = contract().getCluster(type.value, chart.value)
+                val cluster = contract().getCluster(type.value, chart.value)
-                liveData.postValue(streamCluster)
+                updateCluster(type, chart, cluster)
+                liveData.postValue(ViewState.Success(stash))
             } catch (_: Exception) {
             }
         }
     }
 
-    fun nextCluster() {
+    fun nextCluster(type: TopChartsContract.Type, chart: TopChartsContract.Chart) {
         viewModelScope.launch(Dispatchers.IO) {
             supervisorScope {
                 try {
-                    if (streamCluster.hasNext()) {
+                    val target = targetCluster(type, chart)
+                    if (target.hasNext()) {
                         val newCluster = topChartsHelper.getNextStreamCluster(
-                            streamCluster.clusterNextPageUrl
+                            target.clusterNextPageUrl
                         )
 
-                        streamCluster.apply {
+                        updateCluster(type, chart, newCluster)
-                            clusterAppList.addAll(newCluster.clusterAppList)
-                            clusterNextPageUrl = newCluster.clusterNextPageUrl
-                        }
 
-                        liveData.postValue(streamCluster)
+                        liveData.postValue(ViewState.Success(stash))
-                    } else {
                     }
                 } catch (_: Exception) {
                 }
             }
         }
     }
+
+    private fun updateCluster(
+        type: TopChartsContract.Type,
+        chart: TopChartsContract.Chart,
+        newCluster: StreamCluster
+    ) {
+        targetCluster(type, chart).apply {
+            clusterAppList.addAll(newCluster.clusterAppList)
+            clusterNextPageUrl = newCluster.clusterNextPageUrl
+        }
+    }
+
+    private fun targetCluster(
+        type: TopChartsContract.Type,
+        chart: TopChartsContract.Chart
+    ): StreamCluster {
+        // Stash is initialized with empty clusters so this will never return null or throw an exception
+        val cluster = stash.getValue(type).getValue(chart)
+        return cluster
+    }
 }