import { Context, Effect, Effectable, ExecutionStrategy, Function, identity, Predicate, Runtime, Scope, String, Tracer, type Types } from "effect"
import * as React from "react"
import { Hooks } from "./hooks/index.js"
import * as Memoized from "./Memoized.js"


export const TypeId: unique symbol = Symbol.for("effect-fc/Component")
export type TypeId = typeof TypeId

export interface Component<F extends FunctionComponent, E, R>
extends
    Effect.Effect<F, never, Exclude<R, Scope.Scope>>,
    Component.Options
{
    new(_: never): {}
    readonly [TypeId]: TypeId
    readonly ["~FunctionComponent"]: F
    readonly ["~Props"]: FunctionComponent.Props<F>
    readonly ["~Success"]: FunctionComponent.Success<F>
    readonly ["~Error"]: E
    readonly ["~Context"]: R

    /** @internal */
    readonly body: (props: FunctionComponent.Props<F>) => Effect.Effect<FunctionComponent.Success<F>, E, R>

    /** @internal */
    makeFunctionComponent(
        runtimeRef: React.Ref<Runtime.Runtime<Exclude<R, Scope.Scope>>>,
        scope: Scope.Scope,
    ): F
}

export namespace Component {
    export type FunctionComponent<T extends Component<any, any, any>> = T extends Component<infer F, infer _E, infer _R> ? F : never
    export type Error<T extends Component<any, any, any>> = T extends Component<infer _F, infer E, infer _R> ? E : never
    export type Context<T extends Component<any, any, any>> = T extends Component<infer _F, infer _E, infer R> ? R : never

    export type AsComponent<T extends Component<any, any, any>> = Component<FunctionComponent<T>, Error<T>, Context<T>>

    export interface Options {
        readonly displayName?: string
        readonly finalizerExecutionMode: "sync" | "fork"
        readonly finalizerExecutionStrategy: ExecutionStrategy.ExecutionStrategy
    }
}

export type FunctionComponent = (...args: readonly any[]) => React.ReactNode

export namespace FunctionComponent {
    export type Props<T extends FunctionComponent> = T extends (...args: readonly [infer P, ...any[]]) => infer _A ? P : never
    export type Success<T extends FunctionComponent> = T extends (...args: infer _Args) => infer A ? A : never
}


const ComponentProto = Object.freeze({
    ...Effectable.CommitPrototype,
    [TypeId]: TypeId,

    commit: Effect.fnUntraced(function* <F extends FunctionComponent, E, R>(
        this: Component<F, E, R>
    ) {
        const self = this
        const runtimeRef = React.useRef<Runtime.Runtime<Exclude<R, Scope.Scope>>>(null!)
        runtimeRef.current = yield* Effect.runtime<Exclude<R, Scope.Scope>>()

        return React.useCallback(function ScopeProvider(props: FunctionComponent.Props<F>) {
            const scope = Runtime.runSync(runtimeRef.current)(Hooks.useScope(
                Array.from(
                    Context.omit(...nonReactiveTags)(runtimeRef.current.context).unsafeMap.values()
                ),
                self,
            ))

            const FC = React.useMemo(() => {
                const f: React.FC<FunctionComponent.Props<F>> = self.makeFunctionComponent(runtimeRef, scope)
                f.displayName = self.displayName ?? "Anonymous"
                return Memoized.isMemoized(self)
                    ? React.memo(f, self.propsAreEqual)
                    : f
            }, [scope])

            return React.createElement(FC, props)
        }, [])
    }),

    makeFunctionComponent<F extends FunctionComponent, E, R>(
        this: Component<F, E, R>,
        runtimeRef: React.RefObject<Runtime.Runtime<Exclude<R, Scope.Scope>>>,
        scope: Scope.Scope,
    ) {
        return (props: FunctionComponent.Props<F>) => Runtime.runSync(runtimeRef.current)(
            Effect.provideService(this.body(props), Scope.Scope, scope)
        )
    },
} as const)

const defaultOptions = {
    finalizerExecutionMode: "sync",
    finalizerExecutionStrategy: ExecutionStrategy.sequential,
} as const

const nonReactiveTags = [Tracer.ParentSpan] as const


export const isComponent = (u: unknown): u is Component<FunctionComponent, unknown, unknown> => Predicate.hasProperty(u, TypeId)

export const make = <Args extends readonly any[], A extends React.ReactNode, E, R>(
    body: (...args: Args) => Effect.Effect<A, E, R>
): Component<(...args: Args) => A, E, R> => Object.setPrototypeOf(
    Object.assign(function() {}, defaultOptions, {
        body,
        displayName: !String.isEmpty(body.name) ? body.name : undefined,
    }),
    ComponentProto,
)

export const withFunctionComponentSignature: {
    <F extends FunctionComponent>(): <T extends Component<any, any, any>>(self: T) =>
        & Omit<T, keyof Component.AsComponent<T>>
        & Component<F, Component.Error<T>, Component.Context<T>>
} = () => identity

export const withOptions: {
    <T extends Component<any, any, any>>(
        options: Partial<Component.Options>
    ): (self: T) => T
    <T extends Component<any, any, any>>(
        self: T,
        options: Partial<Component.Options>,
    ): T
} = Function.dual(2, <T extends Component<any, any, any>>(
    self: T,
    options: Partial<Component.Options>,
): T => Object.setPrototypeOf(
    Object.assign(function() {}, self, options),
    Object.getPrototypeOf(self),
))

export const withRuntime: {
    <F extends FunctionComponent, E, R>(
        context: React.Context<Runtime.Runtime<R>>,
    ): (self: Component<F, E, Types.NoInfer<R>>) => F
    <F extends FunctionComponent, E, R>(
        self: Component<F, E, Types.NoInfer<R>>,
        context: React.Context<Runtime.Runtime<R>>,
    ): F
} = Function.dual(2, <F extends FunctionComponent, E, R>(
    self: Component<F, E, R>,
    context: React.Context<Runtime.Runtime<R>>,
) => function WithRuntime(props: FunctionComponent.Props<F>) {
    return React.createElement(
        Runtime.runSync(React.useContext(context))(self),
        props,
    )
})