port profile and page to reducer pattern

core/src/main/kotlin/app/dapk/st/core/JobBag.kt

@@ -10,6 +10,11 @@ class JobBag {
         jobs[key] = job
     }
 
+    fun replace(key: String, job: Job) {
+        jobs[key]?.cancel()
+        jobs[key] = job
+    }
+
     fun cancel(key: String) {
         jobs.remove(key)?.cancel()
     }

core/src/testFixtures/kotlin/fake/FakeJobBag.kt

@@ -0,0 +1,9 @@
+package fake
+
+import app.dapk.st.core.JobBag
+import io.mockk.mockk
+
+class FakeJobBag {
+    val instance = mockk<JobBag>()
+}
+

domains/state/src/main/kotlin/app/dapk/state/State.kt

@@ -64,6 +64,48 @@ sealed interface ActionHandler<S> {
     class Delegate<S>(override val key: KClass<Action>, val handler: ReducerScope<S>.(Action) -> ActionHandler<S>) : ActionHandler<S>
 }
 
+data class Combined2<S1, S2>(val state1: S1, val state2: S2)
+
+fun interface SharedStateScope<C> {
+    fun getSharedState(): C
+}
+
+fun <S> shareState(block: SharedStateScope<S>.() -> ReducerFactory<S>): ReducerFactory<S> {
+    var internalScope: ReducerScope<S>? = null
+    val scope = SharedStateScope { internalScope!!.getState() }
+    val combinedFactory = block(scope)
+    return object : ReducerFactory<S> {
+        override fun create(scope: ReducerScope<S>) = combinedFactory.create(scope).also { internalScope = scope }
+        override fun initialState() = combinedFactory.initialState()
+    }
+}
+
+fun <S1, S2> combineReducers(r1: ReducerFactory<S1>, r2: ReducerFactory<S2>): ReducerFactory<Combined2<S1, S2>> {
+    return object : ReducerFactory<Combined2<S1, S2>> {
+        override fun create(scope: ReducerScope<Combined2<S1, S2>>): Reducer<Combined2<S1, S2>> {
+            val r1Scope = object : ReducerScope<S1> {
+                override val coroutineScope: CoroutineScope = scope.coroutineScope
+                override suspend fun dispatch(action: Action) = scope.dispatch(action)
+                override fun getState() = scope.getState().state1
+            }
+
+            val r2Scope = object : ReducerScope<S2> {
+                override val coroutineScope: CoroutineScope = scope.coroutineScope
+                override suspend fun dispatch(action: Action) = scope.dispatch(action)
+                override fun getState() = scope.getState().state2
+            }
+
+            val r1Reducer = r1.create(r1Scope)
+            val r2Reducer = r2.create(r2Scope)
+            return Reducer {
+                Combined2(r1Reducer.reduce(it), r2Reducer.reduce(it))
+            }
+        }
+
+        override fun initialState(): Combined2<S1, S2> = Combined2(r1.initialState(), r2.initialState())
+    }
+}
+
 fun <S> createReducer(
     initialState: S,
     vararg reducers: (ReducerScope<S>) -> ActionHandler<S>,

features/directory/src/test/kotlin/app/dapk/st/directory/DirectoryReducerTest.kt

@@ -1,10 +1,10 @@
 package app.dapk.st.directory
 
-import app.dapk.st.core.JobBag
 import app.dapk.st.directory.state.*
 import app.dapk.st.engine.DirectoryItem
 import app.dapk.st.engine.UnreadCount
 import fake.FakeChatEngine
+import fake.FakeJobBag
 import fixture.aRoomOverview
 import io.mockk.mockk
 import kotlinx.coroutines.flow.flowOf
@@ -91,8 +91,3 @@ class DirectoryReducerTest {
 internal class FakeShortcutHandler {
     val instance = mockk<ShortcutHandler>()
 }
-
-class FakeJobBag {
-    val instance = mockk<JobBag>()
-}
-

features/messenger/src/main/kotlin/app/dapk/st/messenger/gallery/ImageGalleryActivity.kt

@@ -23,9 +23,9 @@ import kotlinx.parcelize.Parcelize
 class ImageGalleryActivity : DapkActivity() {
 
     private val module by unsafeLazy { module<ImageGalleryModule>() }
-    private val viewModel by viewModel {
+    private val imageGalleryState by state {
         val payload = intent.getParcelableExtra("key") as? ImageGalleryActivityPayload
-        module.imageGalleryViewModel(payload!!.roomName)
+        module.imageGalleryState(payload!!.roomName)
     }
 
     override fun onCreate(savedInstanceState: Bundle?) {
@@ -42,7 +42,7 @@ class ImageGalleryActivity : DapkActivity() {
         setContent {
             Surface {
                 PermissionGuard(permissionState) {
-                    ImageGalleryScreen(viewModel, onTopLevelBack = { finish() }) { media ->
+                    ImageGalleryScreen(imageGalleryState, onTopLevelBack = { finish() }) { media ->
                         setResult(RESULT_OK, Intent().setData(media.uri))
                         finish()
                     }

features/messenger/src/main/kotlin/app/dapk/st/messenger/gallery/ImageGalleryModule.kt

@@ -1,18 +1,22 @@
 package app.dapk.st.messenger.gallery
 
 import android.content.ContentResolver
-import app.dapk.st.core.CoroutineDispatchers
+import app.dapk.st.core.*
-import app.dapk.st.core.ProvidableModule
+import app.dapk.st.messenger.gallery.state.ImageGalleryState
+import app.dapk.st.messenger.gallery.state.imageGalleryReducer
 
 class ImageGalleryModule(
     private val contentResolver: ContentResolver,
     private val dispatchers: CoroutineDispatchers,
 ) : ProvidableModule {
 
-    fun imageGalleryViewModel(roomName: String) = ImageGalleryViewModel(
+    fun imageGalleryState(roomName: String): ImageGalleryState = createStateViewModel {
-        FetchMediaFoldersUseCase(contentResolver, dispatchers),
+        imageGalleryReducer(
-        FetchMediaUseCase(contentResolver, dispatchers),
+            roomName = roomName,
-        roomName = roomName,
+            FetchMediaFoldersUseCase(contentResolver, dispatchers),
-    )
+            FetchMediaUseCase(contentResolver, dispatchers),
+            JobBag(),
+        )
+    }
 
 }

features/messenger/src/main/kotlin/app/dapk/st/messenger/gallery/ImageGalleryScreen.kt

@@ -24,35 +24,41 @@ import app.dapk.st.core.components.CenteredLoading
 import app.dapk.st.design.components.GenericError
 import app.dapk.st.design.components.Spider
 import app.dapk.st.design.components.SpiderPage
+import app.dapk.st.messenger.gallery.state.ImageGalleryActions
+import app.dapk.st.messenger.gallery.state.ImageGalleryPage
+import app.dapk.st.messenger.gallery.state.ImageGalleryState
 import coil.compose.rememberAsyncImagePainter
 import coil.request.ImageRequest
 
 @Composable
-fun ImageGalleryScreen(viewModel: ImageGalleryViewModel, onTopLevelBack: () -> Unit, onImageSelected: (Media) -> Unit) {
+fun ImageGalleryScreen(state: ImageGalleryState, onTopLevelBack: () -> Unit, onImageSelected: (Media) -> Unit) {
     LifecycleEffect(onStart = {
-        viewModel.start()
+        state.dispatch(ImageGalleryActions.Visible)
     })
 
     val onNavigate: (SpiderPage<out ImageGalleryPage>?) -> Unit = {
         when (it) {
             null -> onTopLevelBack()
-            else -> viewModel.goTo(it)
+            else -> state.dispatch(PageAction.GoTo(it))
         }
     }
 
-    Spider(currentPage = viewModel.state.page, onNavigate = onNavigate) {
+    Spider(currentPage = state.current.state1.page, onNavigate = onNavigate) {
         item(ImageGalleryPage.Routes.folders) {
-            ImageGalleryFolders(it, onClick = { viewModel.selectFolder(it) }, onRetry = { viewModel.start() })
+            ImageGalleryFolders(
+                it,
+                onClick = { state.dispatch(ImageGalleryActions.SelectFolder(it)) },
+                onRetry = { state.dispatch(ImageGalleryActions.Visible) }
+            )
         }
         item(ImageGalleryPage.Routes.files) {
-            ImageGalleryMedia(it, onImageSelected, onRetry = { viewModel.selectFolder(it.folder) })
+            ImageGalleryMedia(it, onImageSelected, onRetry = { state.dispatch(ImageGalleryActions.SelectFolder(it.folder)) })
         }
     }
-
 }
 
 @Composable
-fun ImageGalleryFolders(state: ImageGalleryPage.Folders, onClick: (Folder) -> Unit, onRetry: () -> Unit) {
+private fun ImageGalleryFolders(state: ImageGalleryPage.Folders, onClick: (Folder) -> Unit, onRetry: () -> Unit) {
     val screenWidth = LocalConfiguration.current.screenWidthDp
 
     val gradient = Brush.verticalGradient(
@@ -108,7 +114,7 @@ fun ImageGalleryFolders(state: ImageGalleryPage.Folders, onClick: (Folder) -> Un
 }
 
 @Composable
-fun ImageGalleryMedia(state: ImageGalleryPage.Files, onFileSelected: (Media) -> Unit, onRetry: () -> Unit) {
+private fun ImageGalleryMedia(state: ImageGalleryPage.Files, onFileSelected: (Media) -> Unit, onRetry: () -> Unit) {
     val screenWidth = LocalConfiguration.current.screenWidthDp
 
     Column {

features/messenger/src/main/kotlin/app/dapk/st/messenger/gallery/ImageGalleryViewModel.kt

@@ -1,89 +0,0 @@
-package app.dapk.st.messenger.gallery
-
-import androidx.lifecycle.viewModelScope
-import app.dapk.st.core.Lce
-import app.dapk.st.design.components.Route
-import app.dapk.st.design.components.SpiderPage
-import app.dapk.st.viewmodel.DapkViewModel
-import kotlinx.coroutines.Job
-import kotlinx.coroutines.launch
-
-class ImageGalleryViewModel(
-    private val foldersUseCase: FetchMediaFoldersUseCase,
-    private val fetchMediaUseCase: FetchMediaUseCase,
-    roomName: String,
-) : DapkViewModel<ImageGalleryState, ImageGalleryEvent>(
-    initialState = ImageGalleryState(
-        page = SpiderPage(
-            route = ImageGalleryPage.Routes.folders,
-            label = "Send to $roomName",
-            parent = null,
-            state = ImageGalleryPage.Folders(Lce.Loading())
-        )
-    )
-) {
-
-    private var currentPageJob: Job? = null
-
-    fun start() {
-        currentPageJob?.cancel()
-        currentPageJob = viewModelScope.launch {
-            val folders = foldersUseCase.fetchFolders()
-            updatePageState<ImageGalleryPage.Folders> { copy(content = Lce.Content(folders)) }
-        }
-
-    }
-
-    fun goTo(page: SpiderPage<out ImageGalleryPage>) {
-        currentPageJob?.cancel()
-        updateState { copy(page = page) }
-    }
-
-    fun selectFolder(folder: Folder) {
-        currentPageJob?.cancel()
-
-        updateState {
-            copy(
-                page = SpiderPage(
-                    route = ImageGalleryPage.Routes.files,
-                    label = page.label,
-                    parent = ImageGalleryPage.Routes.folders,
-                    state = ImageGalleryPage.Files(Lce.Loading(), folder)
-                )
-            )
-        }
-
-        currentPageJob = viewModelScope.launch {
-            val media = fetchMediaUseCase.getMediaInBucket(folder.bucketId)
-            updatePageState<ImageGalleryPage.Files> {
-                copy(content = Lce.Content(media))
-            }
-        }
-    }
-
-    @Suppress("UNCHECKED_CAST")
-    private inline fun <reified S : ImageGalleryPage> updatePageState(crossinline block: S.() -> S) {
-        val page = state.page
-        val currentState = page.state
-        require(currentState is S)
-        updateState { copy(page = (page as SpiderPage<S>).copy(state = block(page.state))) }
-    }
-
-}
-
-data class ImageGalleryState(
-    val page: SpiderPage<out ImageGalleryPage>,
-)
-
-
-sealed interface ImageGalleryPage {
-    data class Folders(val content: Lce<List<Folder>>) : ImageGalleryPage
-    data class Files(val content: Lce<List<Media>>, val folder: Folder) : ImageGalleryPage
-
-    object Routes {
-        val folders = Route<Folders>("Folders")
-        val files = Route<Files>("Files")
-    }
-}
-
-sealed interface ImageGalleryEvent

features/messenger/src/main/kotlin/app/dapk/st/messenger/gallery/PageReducer.kt

@@ -0,0 +1,40 @@
+package app.dapk.st.messenger.gallery
+
+import app.dapk.st.design.components.SpiderPage
+import app.dapk.state.Action
+import app.dapk.state.ReducerFactory
+import app.dapk.state.change
+import app.dapk.state.createReducer
+
+fun <P : Any> createPageReducer(
+    initialPage: SpiderPage<out P>
+): ReducerFactory<PageContainer<P>> {
+    return createReducer(
+        initialState = PageContainer(
+            page = initialPage
+        ),
+
+        change(PageAction.GoTo::class) { action, state ->
+            state.copy(page = action.page as SpiderPage<P>)
+        },
+
+        change(PageAction.UpdatePage::class) { action, state ->
+            val isSamePage = state.page.state::class == action.pageContent::class
+            if (isSamePage) {
+                val updatedPageContent = (state.page as SpiderPage<Any>).copy(state = action.pageContent)
+                state.copy(page = updatedPageContent as SpiderPage<out P>)
+            } else {
+                state
+            }
+        },
+    )
+}
+
+sealed interface PageAction : Action {
+    data class GoTo<P : Any>(val page: SpiderPage<P>) : PageAction
+    data class UpdatePage<P : Any>(val pageContent: P) : PageAction
+}
+
+data class PageContainer<P>(
+    val page: SpiderPage<out P>
+)

features/messenger/src/main/kotlin/app/dapk/st/messenger/gallery/state/ImageGalleryActions.kt

@@ -0,0 +1,9 @@
+package app.dapk.st.messenger.gallery.state
+
+import app.dapk.st.messenger.gallery.Folder
+import app.dapk.state.Action
+
+sealed interface ImageGalleryActions : Action {
+    object Visible : ImageGalleryActions
+    data class SelectFolder(val folder: Folder) : ImageGalleryActions
+}

features/messenger/src/main/kotlin/app/dapk/st/messenger/gallery/state/ImageGalleryReducer.kt

@@ -0,0 +1,59 @@
+package app.dapk.st.messenger.gallery.state
+
+import app.dapk.st.core.JobBag
+import app.dapk.st.core.Lce
+import app.dapk.st.design.components.SpiderPage
+import app.dapk.st.messenger.gallery.*
+import app.dapk.state.*
+import kotlinx.coroutines.launch
+
+fun imageGalleryReducer(
+    roomName: String,
+    foldersUseCase: FetchMediaFoldersUseCase,
+    fetchMediaUseCase: FetchMediaUseCase,
+    jobBag: JobBag,
+) = shareState {
+    combineReducers(
+        createPageReducer(roomName),
+        createImageGalleryPageReducer(jobBag, foldersUseCase, fetchMediaUseCase),
+    )
+}
+
+private fun createPageReducer(roomName: String): ReducerFactory<PageContainer<ImageGalleryPage>> = createPageReducer(
+    initialPage = SpiderPage(
+        route = ImageGalleryPage.Routes.folders,
+        label = "Send to $roomName",
+        parent = null,
+        state = ImageGalleryPage.Folders(Lce.Loading())
+    )
+)
+
+private fun SharedStateScope<Combined2<PageContainer<ImageGalleryPage>, Unit>>.createImageGalleryPageReducer(
+    jobBag: JobBag,
+    foldersUseCase: FetchMediaFoldersUseCase,
+    fetchMediaUseCase: FetchMediaUseCase
+) = createReducer(
+    initialState = Unit,
+
+    async(ImageGalleryActions.Visible::class) {
+        jobBag.replace("page", coroutineScope.launch {
+            val folders = foldersUseCase.fetchFolders()
+            dispatch(PageAction.UpdatePage(ImageGalleryPage.Folders(Lce.Content(folders))))
+        })
+    },
+
+    async(ImageGalleryActions.SelectFolder::class) { action ->
+        val page = SpiderPage(
+            route = ImageGalleryPage.Routes.files,
+            label = getSharedState().state1.page.label,
+            parent = ImageGalleryPage.Routes.folders,
+            state = ImageGalleryPage.Files(Lce.Loading(), action.folder)
+        )
+        dispatch(PageAction.GoTo(page))
+
+        jobBag.replace("page", coroutineScope.launch {
+            val media = fetchMediaUseCase.getMediaInBucket(action.folder.bucketId)
+            dispatch(PageAction.UpdatePage(page.state.copy(content = Lce.Content(media))))
+        })
+    },
+)

features/messenger/src/main/kotlin/app/dapk/st/messenger/gallery/state/ImageGalleryState.kt

@@ -0,0 +1,21 @@
+package app.dapk.st.messenger.gallery.state
+
+import app.dapk.st.core.Lce
+import app.dapk.st.core.State
+import app.dapk.st.design.components.Route
+import app.dapk.st.messenger.gallery.Folder
+import app.dapk.st.messenger.gallery.Media
+import app.dapk.st.messenger.gallery.PageContainer
+import app.dapk.state.Combined2
+
+typealias ImageGalleryState = State<Combined2<PageContainer<ImageGalleryPage>, Unit>, Unit>
+
+sealed interface ImageGalleryPage {
+    data class Folders(val content: Lce<List<Folder>>) : ImageGalleryPage
+    data class Files(val content: Lce<List<Media>>, val folder: Folder) : ImageGalleryPage
+
+    object Routes {
+        val folders = Route<Folders>("Folders")
+        val files = Route<Files>("Files")
+    }
+}

features/messenger/src/test/kotlin/app/dapk/st/messenger/MessengerReducerTest.kt

@@ -12,6 +12,7 @@ import app.dapk.st.matrix.common.asString
 import app.dapk.st.messenger.state.*
 import app.dapk.st.navigator.MessageAttachment
 import fake.FakeChatEngine
+import fake.FakeJobBag
 import fake.FakeMessageOptionsStore
 import fixture.*
 import io.mockk.every
@@ -351,10 +352,6 @@ class FakeCopyToClipboard {
     val instance = mockk<CopyToClipboard>()
 }
 
-class FakeJobBag {
-    val instance = mockk<JobBag>()
-}
-
 class FakeDeviceMeta {
     val instance = mockk<DeviceMeta>()