#39 add test, flow, core modules + up version

gradle/libs.versions.toml

@@ -7,10 +7,10 @@ recyclerViewVersion = "1.1.0"
 swipeRefreshLayoutVersion = "1.1.0"
 ktorClientVersion = "2.0.0"
 coroutinesVersion = "1.6.0-native-mt"
-mokoMvvmVersion = "0.12.0"
-mokoResourcesVersion = "0.18.0"
+mokoMvvmVersion = "0.13.0"
+mokoResourcesVersion = "0.20.1"
 mokoUnitsVersion = "0.8.0"
-mokoPagingVersion = "0.7.1"
+mokoPagingVersion = "0.8.0"
 
 [libraries]
 appCompat = { module = "androidx.appcompat:appcompat", version.ref = "androidAppCompatVersion" }
@@ -24,6 +24,8 @@ mokoUnits = { module = "dev.icerock.moko:units", version.ref = "mokoUnitsVersion
 mokoUnitsDataBinding = { module = "dev.icerock.moko:units-databinding", version.ref = "mokoUnitsVersion" }
 mokoMvvmLiveData = { module = "dev.icerock.moko:mvvm-livedata", version.ref = "mokoMvvmVersion" }
 mokoMvvmState = { module = "dev.icerock.moko:mvvm-state", version.ref = "mokoMvvmVersion" }
+mokoMvvmFlow = { module = "dev.icerock.moko:mvvm-flow", version.ref = "mokoMvvmVersion" }
+mokoMvvmCore = { module = "dev.icerock.moko:mvvm-core", version.ref = "mokoMvvmVersion" }
 kotlinTestJUnit = { module = "org.jetbrains.kotlin:kotlin-test-junit", version.ref = "kotlinVersion" }
 androidCoreTesting = { module = "androidx.arch.core:core-testing", version.ref = "androidCoreTestingVersion" }
 ktorClientMock = { module = "io.ktor:ktor-client-mock", version.ref = "ktorClientVersion" }

paging-core/build.gradle.kts

@@ -0,0 +1,18 @@
+/*
+ * Copyright 2022 IceRock MAG Inc. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+plugins {
+    id("dev.icerock.moko.gradle.multiplatform.mobile")
+    id("dev.icerock.moko.gradle.publication")
+    id("dev.icerock.moko.gradle.stub.javadoc")
+    id("dev.icerock.moko.gradle.detekt")
+}
+
+kotlin {
+  jvm()
+}
+
+dependencies {
+    commonMainImplementation(libs.coroutines)
+}

paging-core/src/androidMain/AndroidManifest.xml

@@ -0,0 +1,2 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest package="dev.icerock.moko.paging.core" />

paging-core/src/commonMain/kotlin/dev/icerock/moko/paging/core/Identify.kt

@@ -0,0 +1,15 @@
+/*
+ * Copyright 2022 IceRock MAG Inc. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package dev.icerock.moko.paging.core
+
+interface IdEntity {
+    val id: Long
+}
+
+class IdComparator<T : IdEntity> : Comparator<T> {
+    override fun compare(a: T, b: T): Int {
+        return if (a.id == b.id) 0 else 1
+    }
+}

paging/src/commonMain/kotlin/dev/icerock/moko/paging/LambdaPagedListDataSource.kt → paging-core/src/commonMain/kotlin/dev/icerock/moko/paging/core/LambdaPagedListDataSource.kt

@@ -2,7 +2,7 @@
  * Copyright 2020 IceRock MAG Inc. Use of this source code is governed by the Apache 2.0 license.
  */
 
-package dev.icerock.moko.paging
+package dev.icerock.moko.paging.core
 
 class LambdaPagedListDataSource<T>(
     private val loadPageLambda: suspend (List<T>?) -> List<T>

paging/src/commonMain/kotlin/dev/icerock/moko/paging/PagedListDataSource.kt → paging-core/src/commonMain/kotlin/dev/icerock/moko/paging/core/PagedListDataSource.kt

@@ -2,7 +2,7 @@
  * Copyright 2020 IceRock MAG Inc. Use of this source code is governed by the Apache 2.0 license.
  */
 
-package dev.icerock.moko.paging
+package dev.icerock.moko.paging.core
 
 interface PagedListDataSource<T> {
     suspend fun loadPage(currentList: List<T>?): List<T>

paging-core/src/commonMain/kotlin/dev/icerock/moko/paging/core/Pagination.kt

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2022 IceRock MAG Inc. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package dev.icerock.moko.paging.core
+
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Deferred
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.sync.Mutex
+import kotlin.coroutines.CoroutineContext
+
+abstract class Pagination<Item>(
+    parentScope: CoroutineScope,
+    protected val dataSource: PagedListDataSource<Item>,
+    protected val comparator: Comparator<Item>,
+    protected val nextPageListener: (Result<List<Item>>) -> Unit,
+    protected val refreshListener: (Result<List<Item>>) -> Unit,
+) : CoroutineScope {
+
+    override val coroutineContext: CoroutineContext = parentScope.coroutineContext
+
+    protected var loadNextPageDeferred: Deferred<List<Item>>? = null
+    protected val listMutex = Mutex()
+
+    fun loadFirstPage() {
+        launch { loadFirstPageSuspend() }
+    }
+
+    fun loadNextPage() {
+        launch { loadNextPageSuspend() }
+    }
+
+    fun refresh() {
+        launch { refreshSuspend() }
+    }
+
+    fun setData(items: List<Item>?) {
+        launch { setDataSuspend(items) }
+    }
+
+    abstract suspend fun loadFirstPageSuspend()
+    abstract suspend fun loadNextPageSuspend()
+    abstract suspend fun refreshSuspend()
+    abstract suspend fun setDataSuspend(items: List<Item>?)
+}

paging/src/commonMain/kotlin/dev/icerock/moko/paging/ReachEndNotifierList.kt → paging-core/src/commonMain/kotlin/dev/icerock/moko/paging/core/ReachEndNotifierList.kt

@@ -2,7 +2,7 @@
  * Copyright 2020 IceRock MAG Inc. Use of this source code is governed by the Apache 2.0 license.
  */
 
-package dev.icerock.moko.paging
+package dev.icerock.moko.paging.core
 
 @Suppress("TooManyFunctions")
 class ReachEndNotifierList<T>(

paging-flow/build.gradle.kts

@@ -0,0 +1,24 @@
+/*
+ * Copyright 2022 IceRock MAG Inc. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+plugins {
+    id("dev.icerock.moko.gradle.multiplatform.mobile")
+    id("dev.icerock.moko.gradle.publication")
+    id("dev.icerock.moko.gradle.stub.javadoc")
+    id("dev.icerock.moko.gradle.detekt")
+}
+
+kotlin {
+  jvm()
+}
+
+dependencies {
+    commonMainImplementation(libs.coroutines)
+
+    commonMainApi(projects.pagingCore)
+    commonMainApi(libs.mokoMvvmFlow)
+    commonMainApi(libs.mokoMvvmState)
+
+    commonTestImplementation(projects.pagingTest)
+}

paging-flow/src/androidMain/AndroidManifest.xml

@@ -0,0 +1,2 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest package="dev.icerock.moko.paging.flow" />

paging-flow/src/commonMain/kotlin/dev/icerock/moko/paging/flow/FlowExt.kt

@@ -0,0 +1,51 @@
+/*
+ * Copyright 2022 IceRock MAG Inc. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package dev.icerock.moko.paging.flow
+
+import dev.icerock.moko.paging.core.ReachEndNotifierList
+import dev.icerock.moko.paging.core.withReachEndNotifier
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.SharingStarted
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.combine
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.flow.stateIn
+
+fun <T> Flow<List<T>>.withLoadingItem(
+    loading: Flow<Boolean>,
+    itemFactory: () -> T
+): Flow<List<T>> = combine(this, loading) { items, nextPageLoading ->
+    if (nextPageLoading) {
+        items + itemFactory()
+    } else {
+        items
+    }
+}
+
+fun <T> Flow<List<T>>.withReachEndNotifier(
+    action: (Int) -> Unit
+): Flow<ReachEndNotifierList<T>> = map { list ->
+    list.withReachEndNotifier(action)
+}
+
+fun <T> Flow<List<T>>.stateWithLoadingItem(
+    parentScope: CoroutineScope,
+    loading: Flow<Boolean>,
+    itemFactory: () -> T
+): StateFlow<List<T>> = combine(this, loading) { items, nextPageLoading ->
+    if (nextPageLoading) {
+        items + itemFactory()
+    } else {
+        items
+    }
+}.stateIn(parentScope, SharingStarted.Lazily, emptyList())
+
+fun <T> Flow<List<T>>.stateWithReachEndNotifier(
+    parentScope: CoroutineScope,
+    action: (Int) -> Unit
+): StateFlow<ReachEndNotifierList<T>> = map { list ->
+    list.withReachEndNotifier(action)
+}.stateIn(parentScope, SharingStarted.Lazily, ReachEndNotifierList(emptyList(), action))

paging-flow/src/commonMain/kotlin/dev/icerock/moko/paging/flow/Pagination.kt

@@ -0,0 +1,160 @@
+/*
+ * Copyright 2022 IceRock MAG Inc. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package dev.icerock.moko.paging.flow
+
+import dev.icerock.moko.mvvm.ResourceState
+import dev.icerock.moko.mvvm.asState
+import dev.icerock.moko.paging.core.PagedListDataSource
+import dev.icerock.moko.paging.core.Pagination
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.async
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+
+class Pagination<Item>(
+    parentScope: CoroutineScope,
+    dataSource: PagedListDataSource<Item>,
+    comparator: Comparator<Item>,
+    nextPageListener: (Result<List<Item>>) -> Unit,
+    refreshListener: (Result<List<Item>>) -> Unit,
+    initValue: List<Item>? = null
+) : Pagination<Item>(
+    parentScope = parentScope,
+    dataSource = dataSource,
+    comparator = comparator,
+    nextPageListener = nextPageListener,
+    refreshListener = refreshListener
+) {
+
+    private val mStateStorage: MutableStateFlow<ResourceState<List<Item>, Throwable>> =
+        MutableStateFlow(initValue.asStateNullIsLoading())
+
+    val state: StateFlow<ResourceState<List<Item>, Throwable>> = mStateStorage
+
+    private val mNextPageLoading: MutableStateFlow<Boolean> = MutableStateFlow(false)
+    val nextPageLoading: StateFlow<Boolean> get() = mNextPageLoading
+
+    private val mEndOfList: MutableStateFlow<Boolean> = MutableStateFlow(false)
+
+    private val mRefreshLoading: MutableStateFlow<Boolean> = MutableStateFlow(false)
+    val refreshLoading: StateFlow<Boolean> get() = mRefreshLoading
+
+    override suspend fun loadFirstPageSuspend() {
+        loadNextPageDeferred?.cancel()
+
+        listMutex.lock()
+
+        mEndOfList.value = false
+        mNextPageLoading.value = false
+        mStateStorage.value = ResourceState.Loading()
+
+        @Suppress("TooGenericExceptionCaught")
+        try {
+            val items: List<Item> = dataSource.loadPage(null)
+            mStateStorage.value = items.asState()
+        } catch (error: Exception) {
+            mStateStorage.value = ResourceState.Failed(error)
+        }
+        listMutex.unlock()
+    }
+
+    @Suppress("ReturnCount")
+    override suspend fun loadNextPageSuspend() {
+        if (mNextPageLoading.value) return
+        if (mRefreshLoading.value) return
+        if (mEndOfList.value) return
+
+        listMutex.lock()
+
+        mNextPageLoading.value = true
+
+        @Suppress("TooGenericExceptionCaught")
+        try {
+            loadNextPageDeferred = this.async {
+                val currentList = mStateStorage.value.dataValue()
+                    ?: throw IllegalStateException("Try to load next page when list is empty")
+                // load next page items
+                val items = dataSource.loadPage(currentList)
+                // remove already exist items
+                val newItems = items.filter { item ->
+                    val existsItem = currentList.firstOrNull { comparator.compare(item, it) == 0 }
+                    existsItem == null
+                }
+                // append new items to current list
+                val newList = currentList.plus(newItems)
+                // mark end of list if no new items
+                if (newItems.isEmpty()) {
+                    mEndOfList.value = true
+                } else {
+                    // save
+                    mStateStorage.value = newList.asState()
+                }
+                newList
+            }
+            val newList = loadNextPageDeferred!!.await()
+
+            // flag
+            mNextPageLoading.value = false
+            // notify
+            nextPageListener(Result.success(newList))
+        } catch (error: Exception) {
+            // flag
+            mNextPageLoading.value = false
+            // notify
+            nextPageListener(Result.failure(error))
+        }
+        listMutex.unlock()
+    }
+
+    override suspend fun refreshSuspend() {
+        loadNextPageDeferred?.cancel()
+        listMutex.lock()
+
+        if (mRefreshLoading.value) {
+            listMutex.unlock()
+            return
+        }
+        if (mNextPageLoading.value) {
+            listMutex.unlock()
+            return
+        }
+
+        mRefreshLoading.value = true
+
+        @Suppress("TooGenericExceptionCaught")
+        try {
+            // load first page items
+            val items = dataSource.loadPage(null)
+            // save
+            mStateStorage.value = items.asState()
+            // flag
+            mEndOfList.value = false
+            mRefreshLoading.value = false
+            // notify
+            refreshListener(Result.success(items))
+        } catch (error: Exception) {
+            // flag
+            mRefreshLoading.value = false
+            // notify
+            refreshListener(Result.failure(error))
+        }
+        listMutex.unlock()
+    }
+
+    override suspend fun setDataSuspend(items: List<Item>?) {
+        listMutex.lock()
+        mStateStorage.value = items.asStateNullIsEmpty()
+        mEndOfList.value = false
+        listMutex.unlock()
+    }
+}
+
+fun <T, E> List<T>?.asStateNullIsEmpty() = asState {
+    ResourceState.Empty<List<T>, E>()
+}
+
+fun <T, E> List<T>?.asStateNullIsLoading() = asState {
+    ResourceState.Loading<List<T>, E>()
+}