import { Schema } from "@effect/schema"
import type { ParseOptions } from "@effect/schema/AST"
import { Effect } from "effect"
import { importTRPCServer } from "../importTRPCServer"
import type { TRPCContextRuntime } from "../TRPCContext"


export const DecodeInput = <A, I>(
    schema:    Schema.Schema<A, I>,
    options?:  ParseOptions,
) => Effect.gen(function*() {
    const { experimental_standaloneMiddleware, TRPCError } = yield* importTRPCServer

    const decode = (value: I) => Schema.decode(schema, options)(value).pipe(
        Effect.matchEffect({
            onSuccess: Effect.succeed,
            onFailure: e => Effect.fail(new TRPCError({
                code: "BAD_REQUEST",
                message: "Could not decode input",
                cause: e,
            })),
        })
    )

    return experimental_standaloneMiddleware<{
        ctx:    TRPCContextRuntime<never>
        input:  I
    }>().create(
        async ({ ctx, input, next }) => next({
            ctx: { decodedInput: await ctx.run(decode(input)) } as const
        })
    )
})