import gleam/dynamic/decode.{type Decoder}
import gleam/option.{type Option}
import gleam/time/timestamp.{type Timestamp}
import spacetraders_models/contract_deliver_good.{type ContractDeliverGood}
import spacetraders_models/contract_payment.{type ContractPayment}
import spacetraders_sdk/internal/time

pub type ContractTerms {
  ContractTerms(
    deadline: Timestamp,
    payment: ContractPayment,
    deliver: Option(List(ContractDeliverGood)),
  )
}

pub fn decoder() -> Decoder(ContractTerms) {
  use deadline <- decode.field("deadline", time.rfc3339_timestamp_decoder())
  use payment <- decode.field("payment", contract_payment.decoder())
  use deliver <- decode.optional_field(
    "deliver",
    option.None,
    decode.optional(decode.list(contract_deliver_good.decoder())),
  )
  decode.success(ContractTerms(deadline:, payment:, deliver:))
}