start add paged/loading component

common/compose/src/commonMain/kotlin/dev/inmo/micro_utils/common/compose/LoadableComponent.kt

@@ -0,0 +1,74 @@
+package dev.inmo.micro_utils.common.compose
+
+import androidx.compose.runtime.*
+import dev.inmo.micro_utils.common.Optional
+import dev.inmo.micro_utils.common.dataOrThrow
+import dev.inmo.micro_utils.common.optional
+
+class LoadableComponentContext<T> internal constructor(
+    presetOptional: Optional<T>,
+) {
+    internal val iterationState: MutableState<Int> = mutableStateOf(0)
+
+    internal var dataOptional: Optional<T> = if (presetOptional.dataPresented) presetOptional else Optional.absent()
+        private set
+    internal val dataState: MutableState<Optional<T>> = mutableStateOf(dataOptional)
+
+    fun reload() {
+        iterationState.value++
+    }
+}
+
+/**
+ * Showing data with ability to reload data
+ *
+ * [block] will be shown when [loader] will complete loading. If you want to reload data, just call
+ * [LoadableComponentContext.reload]
+ */
+@Composable
+fun <T> LoadableComponent(
+    preload: Optional<T>,
+    loader: suspend LoadableComponentContext<T>.() -> T,
+    block: @Composable LoadableComponentContext<T>.(T) -> Unit
+) {
+    val context = remember { LoadableComponentContext(preload) }
+
+    LaunchedEffect(context.iterationState.value) {
+        context.dataState.value = loader(context).optional
+    }
+
+    context.dataState.let {
+        if (it.value.dataPresented) {
+            context.block(it.value.dataOrThrow(IllegalStateException("Data must be presented, but optional has been changed by some way")))
+        }
+    }
+}
+
+/**
+ * Showing data with ability to reload data
+ *
+ * [block] will be shown when [loader] will complete loading. If you want to reload data, just call
+ * [LoadableComponentContext.reload]
+ */
+@Composable
+fun <T> LoadableComponent(
+    preload: T,
+    loader: suspend LoadableComponentContext<T>.() -> T,
+    block: @Composable LoadableComponentContext<T>.(T) -> Unit
+) {
+    LoadableComponent(preload.optional, loader, block)
+}
+
+/**
+ * Showing data with ability to reload data
+ *
+ * [block] will be shown when [loader] will complete loading. If you want to reload data, just call
+ * [LoadableComponentContext.reload]
+ */
+@Composable
+fun <T> LoadableComponent(
+    loader: suspend LoadableComponentContext<T>.() -> T,
+    block: @Composable LoadableComponentContext<T>.(T) -> Unit
+) {
+    LoadableComponent(Optional.absent(), loader, block)
+}

pagination/common/src/commonMain/kotlin/dev/inmo/micro_utils/pagination/Pagination.kt

@@ -40,6 +40,8 @@ fun Pagination.intersect(
 inline val Pagination.isFirstPage
     get() = page == 0
 
+fun Pagination.firstPage() = if (isFirstPage) this else SimplePagination(0, size)
+
 /**
  * First number in index of objects. It can be used as offset for databases or other data sources
  */

pagination/compose/build.gradle

@@ -0,0 +1,20 @@
+plugins {
+    id "org.jetbrains.kotlin.multiplatform"
+    id "org.jetbrains.kotlin.plugin.serialization"
+    id "com.android.library"
+    alias(libs.plugins.jb.compose)
+    alias(libs.plugins.kt.jb.compose)
+}
+
+apply from: "$mppComposeJvmJsAndroidLinuxMingwLinuxArm64Project"
+
+kotlin {
+    sourceSets {
+        commonMain {
+            dependencies {
+                api project(":micro_utils.pagination.common")
+                api project(":micro_utils.common.compose")
+            }
+        }
+    }
+}

pagination/compose/src/commonMain/kotlin/InfinityPagedComponent.kt

@@ -0,0 +1,99 @@
+package dev.inmo.micro_utils.pagination.compose
+
+import androidx.compose.runtime.*
+import dev.inmo.micro_utils.common.Optional
+import dev.inmo.micro_utils.common.dataOrThrow
+import dev.inmo.micro_utils.common.optional
+import dev.inmo.micro_utils.pagination.*
+
+class InfinityPagedComponentContext<T> internal constructor(
+    preset: List<T>? = null,
+    initialPage: Int,
+    size: Int
+) {
+    internal val iterationState: MutableState<Pair<Int, Pagination>> = mutableStateOf(0 to SimplePagination(preset ?.page ?: initialPage, preset ?.size ?: size))
+
+    internal var dataOptional: List<T>? = preset
+        private set
+    internal val dataState: MutableState<List<T>?> = mutableStateOf(dataOptional)
+
+    fun loadNext() {
+        iterationState.value = iterationState.value.let {
+            if ((dataState.value as? PaginationResult<*>) ?.isLastPage == true) return
+            (it.first + 1) to it.second.nextPage()
+        }
+    }
+    fun reload() {
+        iterationState.value = iterationState.value.let {
+            (it.first + 1) to (it.second.firstPage())
+        }
+    }
+}
+
+@Composable
+internal fun <T> InfinityPagedComponent(
+    preload: List<T>?,
+    initialPage: Int,
+    size: Int,
+    loader: suspend PagedComponentContext<T>.(Pagination) -> PaginationResult<T>,
+    block: @Composable PagedComponentContext<T>.(List<T>) -> Unit
+) {
+    val context = remember { InfinityPagedComponentContext(preload, initialPage, size) }
+
+    LaunchedEffect(context.iterationState.value) {
+        context.dataState.value = loader(context, context.iterationState.value.second)
+    }
+
+    context.dataState.value ?.let {
+        context.block()
+    }
+}
+
+@Composable
+fun <T> InfinityPagedComponent(
+    preload: PaginationResult<T>,
+    loader: suspend PagedComponentContext<T>.(Pagination) -> PaginationResult<T>,
+    block: @Composable PagedComponentContext<T>.(PaginationResult<T>) -> Unit
+) {
+    PagedComponent(
+        preload,
+        preload.page,
+        preload.size,
+        loader,
+        block
+    )
+}
+
+@Composable
+fun <T> InfinityPagedComponent(
+    pageInfo: Pagination,
+    loader: suspend PagedComponentContext<T>.(Pagination) -> PaginationResult<T>,
+    block: @Composable PagedComponentContext<T>.(PaginationResult<T>) -> Unit
+) {
+    PagedComponent(
+        null,
+        pageInfo.page,
+        pageInfo.size,
+        loader,
+        block
+    )
+}
+
+@Composable
+fun <T> InfinityPagedComponent(
+    initialPage: Int,
+    size: Int,
+    loader: suspend PagedComponentContext<T>.(Pagination) -> PaginationResult<T>,
+    block: @Composable PagedComponentContext<T>.(PaginationResult<T>) -> Unit
+) {
+    PagedComponent(null, initialPage, size, loader, block)
+}
+
+@Composable
+fun <T> InfinityPagedComponent(
+    size: Int,
+    loader: suspend PagedComponentContext<T>.(Pagination) -> PaginationResult<T>,
+    block: @Composable PagedComponentContext<T>.(PaginationResult<T>) -> Unit
+) {
+    PagedComponent(0, size, loader, block)
+}

pagination/compose/src/commonMain/kotlin/PagedComponent.kt

@@ -0,0 +1,108 @@
+package dev.inmo.micro_utils.pagination.compose
+
+import androidx.compose.runtime.*
+import dev.inmo.micro_utils.common.Optional
+import dev.inmo.micro_utils.common.dataOrThrow
+import dev.inmo.micro_utils.common.optional
+import dev.inmo.micro_utils.pagination.*
+
+class PagedComponentContext<T> internal constructor(
+    preset: PaginationResult<T>? = null,
+    initialPage: Int,
+    size: Int
+) {
+    internal val iterationState: MutableState<Pair<Int, Pagination>> = mutableStateOf(0 to SimplePagination(preset ?.page ?: initialPage, preset ?.size ?: size))
+
+    internal var dataOptional: PaginationResult<T>? = preset
+        private set
+    internal val dataState: MutableState<PaginationResult<T>?> = mutableStateOf(dataOptional)
+
+    fun loadNext() {
+        iterationState.value = iterationState.value.let {
+            if (dataState.value ?.isLastPage == true) return
+            (it.first + 1) to it.second.nextPage()
+        }
+    }
+    fun loadPrevious() {
+        iterationState.value = iterationState.value.let {
+            if (it.second.isFirstPage) return
+            (it.first - 1) to SimplePagination(
+                it.second.page - 1,
+                it.second.size
+            )
+        }
+    }
+    fun reload() {
+        iterationState.value = iterationState.value.let {
+            it.copy(it.first + 1)
+        }
+    }
+}
+
+@Composable
+internal fun <T> PagedComponent(
+    preload: PaginationResult<T>?,
+    initialPage: Int,
+    size: Int,
+    loader: suspend PagedComponentContext<T>.(Pagination) -> PaginationResult<T>,
+    block: @Composable PagedComponentContext<T>.(PaginationResult<T>) -> Unit
+) {
+    val context = remember { PagedComponentContext(preload, initialPage, size) }
+
+    LaunchedEffect(context.iterationState.value) {
+        context.dataState.value = loader(context, context.iterationState.value.second)
+    }
+
+    context.dataState.value ?.let {
+        context.block(it)
+    }
+}
+
+@Composable
+fun <T> PagedComponent(
+    preload: PaginationResult<T>,
+    loader: suspend PagedComponentContext<T>.(Pagination) -> PaginationResult<T>,
+    block: @Composable PagedComponentContext<T>.(PaginationResult<T>) -> Unit
+) {
+    PagedComponent(
+        preload,
+        preload.page,
+        preload.size,
+        loader,
+        block
+    )
+}
+
+@Composable
+fun <T> PagedComponent(
+    pageInfo: Pagination,
+    loader: suspend PagedComponentContext<T>.(Pagination) -> PaginationResult<T>,
+    block: @Composable PagedComponentContext<T>.(PaginationResult<T>) -> Unit
+) {
+    PagedComponent(
+        null,
+        pageInfo.page,
+        pageInfo.size,
+        loader,
+        block
+    )
+}
+
+@Composable
+fun <T> PagedComponent(
+    initialPage: Int,
+    size: Int,
+    loader: suspend PagedComponentContext<T>.(Pagination) -> PaginationResult<T>,
+    block: @Composable PagedComponentContext<T>.(PaginationResult<T>) -> Unit
+) {
+    PagedComponent(null, initialPage, size, loader, block)
+}
+
+@Composable
+fun <T> PagedComponent(
+    size: Int,
+    loader: suspend PagedComponentContext<T>.(Pagination) -> PaginationResult<T>,
+    block: @Composable PagedComponentContext<T>.(PaginationResult<T>) -> Unit
+) {
+    PagedComponent(0, size, loader, block)
+}

settings.gradle

@@ -11,6 +11,7 @@ String[] includes = [
     ":koin:generator:test",
     ":selector:common",
     ":pagination:common",
+    ":pagination:compose",
     ":pagination:exposed",
     ":pagination:ktor:common",
     ":pagination:ktor:server",