import { Effect, Match } from "effect"
import type { TRPCContextTransaction } from "./TRPCContext"
import { importTRPCServer } from "./importTRPCServer"


export const ExpressOnly = importTRPCServer.pipe(Effect.map(({
    experimental_standaloneMiddleware,
    TRPCError,
}) => experimental_standaloneMiddleware<{
    ctx: { readonly transaction: TRPCContextTransaction }
}>().create(opts =>
    Match.value(opts.ctx.transaction).pipe(
        Match.tag("Express", transaction =>
            opts.next({ ctx: { transaction } })
        ),

        Match.orElse(() => {
            throw new TRPCError({
                code: "BAD_REQUEST",
                message: "Only Express backend is supported by this procedure",
            })
        }),
    )
)))