//// Add-form decoding and genesis-event construction: the write surface the
//// lexicon widened (sleeveGrade, rating, folder, price, counterparty) must
//// decode correctly, reject an out-of-range rating, and land on the written
//// record unchanged.

import at_record/gen/defs
import at_record_server/handlers/shelf.{
  type AddForm, AddForm, add_form_decoder, genesis_event,
}
import at_record_server/provenance
import gleam/json
import gleam/option.{None, Some}
import gleam/result

fn decode_form(body: String) -> Result(AddForm, Nil) {
  json.parse(body, add_form_decoder())
  |> result.replace_error(Nil)
}

pub fn add_form_decodes_the_widened_fields_test() {
  let body =
    "{\"title\":\"Spiderland\",\"artist\":\"Slint\",\"sleeveGrade\":\"VG+\",\"rating\":4,\"folder\":\"Rock A-M\",\"price\":{\"amount\":4000,\"currency\":\"EUR\"},\"counterparty\":\"Record shop\"}"
  let assert Ok(form) = decode_form(body)
  assert form.sleeve_grade == Some("VG+")
  assert form.rating == Some(4)
  assert form.folder == Some("Rock A-M")
  assert form.price == Some(defs.Price(amount: 4000, currency: "EUR"))
  assert form.counterparty == Some("Record shop")
}

pub fn add_form_omits_absent_widened_fields_test() {
  let body = "{\"title\":\"Spiderland\",\"artist\":\"Slint\"}"
  let assert Ok(form) = decode_form(body)
  assert form.sleeve_grade == None
  assert form.rating == None
  assert form.folder == None
  assert form.price == None
  assert form.counterparty == None
}

pub fn add_form_rejects_rating_below_one_test() {
  let body = "{\"title\":\"Spiderland\",\"artist\":\"Slint\",\"rating\":0}"
  assert decode_form(body) == Error(Nil)
}

pub fn add_form_rejects_rating_above_five_test() {
  let body = "{\"title\":\"Spiderland\",\"artist\":\"Slint\",\"rating\":6}"
  assert decode_form(body) == Error(Nil)
}

pub fn add_form_accepts_rating_at_bounds_test() {
  let assert Ok(low) =
    decode_form("{\"title\":\"t\",\"artist\":\"a\",\"rating\":1}")
  let assert Ok(high) =
    decode_form("{\"title\":\"t\",\"artist\":\"a\",\"rating\":5}")
  assert low.rating == Some(1)
  assert high.rating == Some(5)
}

fn blank_form() -> AddForm {
  AddForm(
    title: "Spiderland",
    artist: "Slint",
    format: None,
    year: None,
    status: "owned",
    media_grade: None,
    sleeve_grade: None,
    rating: None,
    folder: None,
    notes: None,
    thumb_url: None,
    cover_url: None,
    discogs_id: None,
    price: None,
    counterparty: None,
  )
}

pub fn genesis_event_threads_the_widened_fields_onto_the_record_test() {
  let form =
    AddForm(
      ..blank_form(),
      sleeve_grade: Some("NM"),
      rating: Some(5),
      folder: Some("Rock A-M"),
      price: Some(defs.Price(amount: 4000, currency: "EUR")),
      counterparty: Some("Record shop"),
    )
  let event =
    genesis_event(
      form,
      None,
      None,
      provenance.source("manual"),
      None,
      "2026-01-01T00:00:00Z",
    )
  assert event.sleeve_grade == Some("NM")
  assert event.rating == Some(5)
  assert event.folder == Some("Rock A-M")
  assert event.price == Some(defs.Price(amount: 4000, currency: "EUR"))
  assert event.counterparty == Some("Record shop")
}

pub fn genesis_event_omits_absent_widened_fields_test() {
  let event =
    genesis_event(
      blank_form(),
      None,
      None,
      provenance.source("manual"),
      None,
      "2026-01-01T00:00:00Z",
    )
  assert event.sleeve_grade == None
  assert event.rating == None
  assert event.folder == None
  assert event.price == None
  assert event.counterparty == None
}