packages/effect-fc/src/Form.ts

@@ -28,7 +28,6 @@ extends Pipeable.Pipeable {
 class FormImpl<in out A, in out I = A, out R = never, in out SA = void, in out SE = A, out SR = never>
 extends Pipeable.Class() implements Form<A, I, R, SA, SE, SR> {
     readonly [FormTypeId]: FormTypeId = FormTypeId
-    readonly canSubmitSubscribable: Subscribable.Subscribable<boolean>
 
     constructor(
         readonly schema: Schema.Schema<A, I, R>,
@@ -39,10 +38,44 @@ extends Pipeable.Class() implements Form<A, I, R, SA, SE, SR> {
         readonly errorRef: SubscriptionRef.SubscriptionRef<Option.Option<ParseResult.ParseError>>,
         readonly isValidatingRef: SubscriptionRef.SubscriptionRef<boolean>,
         readonly submitStateRef: SubscriptionRef.SubscriptionRef<AsyncData.AsyncData<SA, SE>>,
+
+        readonly canSubmitSubscribable: Subscribable.Subscribable<boolean>,
     ) {
         super()
+    }
+}
 
-        this.canSubmitSubscribable = pipe(
+export namespace make {
+    export interface Options<in out A, in out I, out R, in out SA = void, in out SE = A, out SR = never> {
+        readonly schema: Schema.Schema<A, I, R>
+        readonly initialEncodedValue: NoInfer<I>
+        readonly submit: (value: NoInfer<A>) => Effect.Effect<SA, SE, SR>
+    }
+}
+
+export const make: {
+    <A, I = A, R = never, SA = void, SE = A, SR = never>(
+        options: make.Options<A, I, R, SA, SE, SR>
+    ): Effect.Effect<Form<A, I, R, SA, SE, SR>>
+} = Effect.fnUntraced(function* <A, I = A, R = never, SA = void, SE = A, SR = never>(
+    options: make.Options<A, I, R, SA, SE, SR>
+) {
+    const valueRef = yield* SubscriptionRef.make(Option.none<A>())
+    const errorRef = yield* SubscriptionRef.make(Option.none<ParseResult.ParseError>())
+    const isValidatingRef = yield* SubscriptionRef.make(false)
+    const submitStateRef = yield* SubscriptionRef.make(AsyncData.noData<SA, SE>())
+
+    return new FormImpl(
+        options.schema,
+        options.submit,
+
+        valueRef,
+        yield* SubscriptionRef.make(options.initialEncodedValue),
+        errorRef,
+        isValidatingRef,
+        submitStateRef,
+
+        pipe(
             <A>([value, error, isValidating, submitState]: readonly [
                 Option.Option<A>,
                 Option.Option<ParseResult.ParseError>,
@@ -64,34 +97,7 @@ extends Pipeable.Class() implements Form<A, I, R, SA, SE, SR> {
                     )
                 },
             }),
-        )
-    }
-}
-
-export namespace make {
-    export interface Options<in out A, in out I, out R, in out SA = void, in out SE = A, out SR = never> {
-        readonly schema: Schema.Schema<A, I, R>
-        readonly initialEncodedValue: NoInfer<I>
-        readonly submit: (value: NoInfer<A>) => Effect.Effect<SA, SE, SR>
-    }
-}
-
-export const make: {
-    <A, I = A, R = never, SA = void, SE = A, SR = never>(
-        options: make.Options<A, I, R, SA, SE, SR>
-    ): Effect.Effect<Form<A, I, R, SA, SE, SR>>
-} = Effect.fnUntraced(function* <A, I = A, R = never, SA = void, SE = A, SR = never>(
-    options: make.Options<A, I, R, SA, SE, SR>
-) {
-    return new FormImpl(
-        options.schema,
-        options.submit,
-
-        yield* SubscriptionRef.make(Option.none<A>()),
-        yield* SubscriptionRef.make(options.initialEncodedValue),
-        yield* SubscriptionRef.make(Option.none<ParseResult.ParseError>()),
-        yield* SubscriptionRef.make(false),
-        yield* SubscriptionRef.make(AsyncData.noData<SA, SE>()),
+        ),
     )
 })
 
@@ -292,3 +298,52 @@ export const useInput: {
 
     return { value, setValue, issues }
 })
+
+export namespace useOptionalInput {
+    export interface Options<I extends Option.Option<any>> extends useInput.Options {
+        readonly defaultValue: Option.Option.Value<I>
+    }
+
+    export interface Result<T> extends useInput.Result<T> {}
+}
+
+export const useOptionalInput: {
+    <A, I extends Option.Option<any>>(
+        field: FormField<A, I>,
+        options: useOptionalInput.Options<I>,
+    ): Effect.Effect<useOptionalInput.Result<Option.Option.Value<I>>, NoSuchElementException>
+} = Effect.fnUntraced(function* <A, I extends Option.Option<any>>(
+    field: FormField<A, I>,
+    options: useOptionalInput.Options<I>,
+) {
+    const internalValueRef = yield* Hooks.useMemo(() => field.encodedValueRef.pipe(
+        Effect.map(Option.match({
+            onSome: identity,
+            onNone: () => options.defaultValue,
+        })),
+        Effect.andThen(SubscriptionRef.make),
+    ), [field])
+    const [value, setValue] = yield* Hooks.useRefState(internalValueRef)
+    const [issues] = yield* Hooks.useSubscribables(field.issuesSubscribable)
+
+    yield* Hooks.useFork(() => Effect.all([
+        Stream.runForEach(
+            Stream.drop(field.encodedValueRef, 1),
+            upstreamEncodedValue => Effect.whenEffect(
+                Ref.set(internalValueRef, upstreamEncodedValue),
+                Effect.andThen(internalValueRef, internalValue => !Equal.equals(upstreamEncodedValue, internalValue)),
+            ),
+        ),
+
+        Stream.runForEach(
+            internalValueRef.changes.pipe(
+                Stream.drop(1),
+                Stream.changesWith(Equivalence.strict()),
+                options?.debounce ? Stream.debounce(options.debounce) : identity,
+            ),
+            internalValue => Ref.set(field.encodedValueRef, internalValue),
+        ),
+    ], { concurrency: "unbounded" }), [field, internalValueRef])
+
+    return { value, setValue, issues }
+})