Todo state refactoring

packages/example/src/todo/Todo.tsx

@@ -4,10 +4,10 @@ import { TextAreaInput } from "@/lib/TextAreaInput"
 import { TextFieldInput } from "@/lib/TextFieldInput"
 import { Box, Button, Flex, IconButton } from "@radix-ui/themes"
 import { GetRandomValues, makeUuid4 } from "@typed/id"
-import { Chunk, DateTime, Effect, flow, identity, Match, Option, Ref, Runtime, Schema, SubscriptionRef } from "effect"
+import { Chunk, DateTime, Effect, Match, Option, Ref, Runtime, Schema, Stream, SubscriptionRef } from "effect"
 import { Component, Memo } from "effect-fc"
 import { useMemo, useOnce, useSubscribe } from "effect-fc/hooks"
-import { SubscriptionSubRef } from "effect-fc/types"
+import { Subscribable, SubscriptionSubRef } from "effect-fc/types"
 import { FaArrowDown, FaArrowUp } from "react-icons/fa"
 import { FaDeleteLeft } from "react-icons/fa6"
 import { TodosState } from "./TodosState.service"
@@ -38,14 +38,11 @@ export class Todo extends Component.makeUntraced(function* Todo(props: TodoProps
     const { ref, indexRef, contentRef, completedAtRef } = yield* useMemo(() => Match.value(props).pipe(
         Match.tag("new", () => Effect.Do.pipe(
             Effect.bind("ref", () => Effect.andThen(makeTodo, SubscriptionRef.make)),
-            Effect.bind("indexRef", () => SubscriptionRef.make(-1)),
+            Effect.let("indexRef", () => Subscribable.make({ get: Effect.succeed(-1), changes: Stream.empty })),
         )),
         Match.tag("edit", ({ id }) => Effect.Do.pipe(
-            Effect.let("ref", () => SubscriptionSubRef.makeFromChunkFindFirst(state.ref, v => v.id === id)),
-            Effect.let("indexRef", () => SubscriptionSubRef.makeFromGetSet(state.ref, {
-                get: flow(Chunk.findFirstIndex(v => v.id === id), Option.getOrThrow),
-                set: identity,
-            })),
+            Effect.let("ref", () => state.getElementRef(id)),
+            Effect.let("indexRef", () => state.getIndexSubscribable(id)),
         )),
         Match.exhaustive,
 
@@ -93,52 +90,19 @@ export class Todo extends Component.makeUntraced(function* Todo(props: TodoProps
                 <Flex direction="column" justify="center" align="center" gap="1">
                     <IconButton
                         disabled={index <= 0}
-                        onClick={() => Runtime.runSync(runtime)(
-                            SubscriptionRef.updateEffect(state.ref, todos => Effect.Do.pipe(
-                                Effect.bind("todo", () => ref),
-                                Effect.bind("index", () => Chunk.findFirstIndex(todos, v => v.id === props.id)),
-                                Effect.bind("previous", ({ index }) => Chunk.get(todos, index - 1)),
-                                Effect.andThen(({ todo, index, previous }) => index > 0
-                                    ? todos.pipe(
-                                        Chunk.replace(index, previous),
-                                        Chunk.replace(index - 1, todo),
-                                    )
-                                    : todos
-                                ),
-                            ))
-                        )}
+                        onClick={() => Runtime.runSync(runtime)(state.moveLeft(props.id))}
                     >
                         <FaArrowUp />
                     </IconButton>
 
                     <IconButton
                         disabled={index >= size - 1}
-                        onClick={() => Runtime.runSync(runtime)(
-                            SubscriptionRef.updateEffect(state.ref, todos => Effect.Do.pipe(
-                                Effect.bind("todo", () => ref),
-                                Effect.bind("index", () => Chunk.findFirstIndex(todos, v => v.id === props.id)),
-                                Effect.bind("next", ({ index }) => Chunk.get(todos, index + 1)),
-                                Effect.andThen(({ todo, index, next }) => index < Chunk.size(todos) - 1
-                                    ? todos.pipe(
-                                        Chunk.replace(index, next),
-                                        Chunk.replace(index + 1, todo),
-                                    )
-                                    : todos
-                                ),
-                            ))
-                        )}
+                        onClick={() => Runtime.runSync(runtime)(state.moveRight(props.id))}
                     >
                         <FaArrowDown />
                     </IconButton>
 
-                    <IconButton
-                        onClick={() => Runtime.runSync(runtime)(
-                            SubscriptionRef.updateEffect(state.ref, todos => Effect.andThen(
-                                Chunk.findFirstIndex(todos, v => v.id === props.id),
-                                index => Chunk.remove(todos, index),
-                            ))
-                        )}
-                    >
+                    <IconButton onClick={() => Runtime.runSync(runtime)(state.remove(props.id))}>
                         <FaDeleteLeft />
                     </IconButton>
                 </Flex>

packages/example/src/todo/TodosState.service.ts

@@ -2,7 +2,7 @@ import { Todo } from "@/domain"
 import { KeyValueStore } from "@effect/platform"
 import { BrowserKeyValueStore } from "@effect/platform-browser"
 import { Chunk, Console, Effect, Option, Schema, Stream, SubscriptionRef } from "effect"
-import { Subscribable } from "effect-fc/types"
+import { Subscribable, SubscriptionSubRef } from "effect-fc/types"
 
 
 export class TodosState extends Effect.Service<TodosState>()("TodosState", {
@@ -18,7 +18,6 @@ export class TodosState extends Effect.Service<TodosState>()("TodosState", {
                 onNone: () => Effect.succeed(Chunk.empty()),
             }))
         )
-
         const saveToLocalStorage = (todos: Chunk.Chunk<Todo.Todo>) => Effect.andThen(
             Console.log("Saving todos to local storage..."),
             Chunk.isNonEmpty(todos)
@@ -32,12 +31,6 @@ export class TodosState extends Effect.Service<TodosState>()("TodosState", {
         )
 
         const ref = yield* SubscriptionRef.make(yield* readFromLocalStorage)
-
-        const sizeSubscribable = Subscribable.make({
-            get: Effect.andThen(ref, Chunk.size),
-            get changes() { return Stream.map(ref.changes, Chunk.size) },
-        })
-
         yield* Effect.forkScoped(ref.changes.pipe(
             Stream.debounce("500 millis"),
             Stream.runForEach(saveToLocalStorage),
@@ -47,7 +40,54 @@ export class TodosState extends Effect.Service<TodosState>()("TodosState", {
             Effect.ignore,
         ))
 
-        return { ref, sizeSubscribable } as const
+        const sizeSubscribable = Subscribable.make({
+            get: Effect.andThen(ref, Chunk.size),
+            get changes() { return Stream.map(ref.changes, Chunk.size) },
+        })
+        const getElementRef = (id: string) => SubscriptionSubRef.makeFromChunkFindFirst(ref, v => v.id === id)
+        const getIndexSubscribable = (id: string) => Subscribable.make({
+            get: Effect.flatMap(ref, Chunk.findFirstIndex(v => v.id === id)),
+            get changes() { return Stream.flatMap(ref.changes, Chunk.findFirstIndex(v => v.id === id)) },
+        })
+
+        const moveLeft = (id: string) => SubscriptionRef.updateEffect(ref, todos => Effect.Do.pipe(
+            Effect.bind("index", () => Chunk.findFirstIndex(todos, v => v.id === id)),
+            Effect.bind("todo", ({ index }) => Chunk.get(todos, index)),
+            Effect.bind("previous", ({ index }) => Chunk.get(todos, index - 1)),
+            Effect.andThen(({ todo, index, previous }) => index > 0
+                ? todos.pipe(
+                    Chunk.replace(index, previous),
+                    Chunk.replace(index - 1, todo),
+                )
+                : todos
+            ),
+        ))
+        const moveRight = (id: string) => SubscriptionRef.updateEffect(ref, todos => Effect.Do.pipe(
+            Effect.bind("index", () => Chunk.findFirstIndex(todos, v => v.id === id)),
+            Effect.bind("todo", ({ index }) => Chunk.get(todos, index)),
+            Effect.bind("next", ({ index }) => Chunk.get(todos, index + 1)),
+            Effect.andThen(({ todo, index, next }) => index < Chunk.size(todos) - 1
+                ? todos.pipe(
+                    Chunk.replace(index, next),
+                    Chunk.replace(index + 1, todo),
+                )
+                : todos
+            ),
+        ))
+        const remove = (id: string) => SubscriptionRef.updateEffect(ref, todos => Effect.andThen(
+            Chunk.findFirstIndex(todos, v => v.id === id),
+            index => Chunk.remove(todos, index),
+        ))
+
+        return {
+            ref,
+            sizeSubscribable,
+            getElementRef,
+            getIndexSubscribable,
+            moveLeft,
+            moveRight,
+            remove,
+        } as const
     }),
 
     dependencies: [BrowserKeyValueStore.layerLocalStorage],