Mapping the success value and errors to final object

import "dotenv/config"

import { Effect } from "effect"

class HttpError {
  readonly _tag = "HttpError"
}

class ValidationErrors {
  readonly _tag = "ValidationErrors"
  public constructor(public readonly fields: { [x: string]: string[] }) {}
}

class ValidationError extends ValidationErrors {
  public constructor(property: string, message: string) {
    super({ [property]: [message] })
  }
}

class GeneralError {
  readonly _tag = "GeneralError"
}

const generateResponse = <
  A,
  R,
  T extends Effect.Effect<A, ValidationErrors | GeneralError, R extends unknown ? never : R>,
>(
  effect: T
) => {
  return effect
    .pipe(Effect.map((value) => ({ type: "success" as const, value: value as A })))
    .pipe(
      Effect.catchTag("ValidationErrors", (e) =>
        Effect.succeed({
          type: "failure" as const,
          fields: e.fields,
        })
      )
    )
    .pipe(
      Effect.catchAll(() =>
        Effect.succeed({
          type: "failure" as const,
          fields: {} as { [x: string]: string[] },
        })
      )
    )
}

function validationErrors(fields: { [x: string]: string[] }) {
  return Effect.fail(new ValidationErrors(fields))
}

function validationError(property: string, message: string) {
  return validationErrors({ [property]: [message] })
}

const program = Effect.gen(function* (_) {
  yield* _(Effect.succeed("hola"))
  yield* _(Math.random() > 0.5 ? Effect.fail(new HttpError()) : Effect.succeed("1"))
  yield* _(validationError("Email", "Ya existe un usuario con este email"))
  return yield* _(Math.random() > 0.5 ? Effect.fail(new GeneralError()) : Effect.succeed("2"))
}).pipe(
  Effect.catchTag("HttpError", () => validationError("email", "Hola")),
  generateResponse
)

const someServerAction = async () => await Effect.runPromise(program)