Nonemm/src/Nonemm.Contests/Rules/Arrl10Metre.cs

using Nonemm.Contests.Multipliers;
using Nonemm.Core;
using Nonemm.Core.Country;

namespace Nonemm.Contests.Rules;

/// The ARRL 10 metre contest. A CW contact is 4 points and a phone contact 2.
/// US, Canadian and Mexican stations send a state or province, everyone else a
/// serial number, and both the states and the countries are multipliers, each
/// counted once per mode: the contest is one band, and CW and phone count
/// separately.
public sealed class Arrl10Metre : Contest
{
    public string Name => "ARRL10M";

    public string DisplayName => "ARRL 10 Metre Contest";

    public string CabrilloName => "ARRL-10";

    /// One box takes the state, province or serial number the other station
    /// sends, as N1MM has it. The sent serial box is there only where this
    /// station sends a number rather than a state.
    public IReadOnlyList<ExchangeField> ExchangeFieldsFor(StationInfo me) => SendsState(me.CountryPrefix)
        ?
        [
            new ExchangeField("Snt", ExchangeSlot.SentReport, ExchangeFieldKind.Report, IsRequired: false),
            new ExchangeField("Rcv", ExchangeSlot.ReceivedReport, ExchangeFieldKind.Report),
            new ExchangeField("Exch", ExchangeSlot.Exchange1, ExchangeFieldKind.Text) { Width = 6 },
        ]
        :
        [
            new ExchangeField("Snt", ExchangeSlot.SentReport, ExchangeFieldKind.Report, IsRequired: false),
            new ExchangeField("SentNR", ExchangeSlot.SentNumber, ExchangeFieldKind.Number, IsRequired: false),
            new ExchangeField("Rcv", ExchangeSlot.ReceivedReport, ExchangeFieldKind.Report),
            new ExchangeField("Exch", ExchangeSlot.Exchange1, ExchangeFieldKind.Text) { Width = 6 },
        ];

    /// A number is a serial and anything else is a state or province.
    public Qso FromExchange1(Qso qso, string typed) =>
        int.TryParse(typed, out int number)
            ? qso with { ReceivedNumber = number, Section = "" }
            : qso with { ReceivedNumber = 0, Section = typed.Trim().ToUpperInvariant() };

    public IReadOnlyList<string> MultiplierNames => ["States", "Countries"];

    public DupeScope DupeScope => DupeScope.PerMode;

    public bool HasSerialNumbers => true;

    public IReadOnlyList<ModeCategory> Modes => [ModeCategory.Cw, ModeCategory.Phone];

    public string SentExchangeFor(StationInfo me) =>
        SendsState(me.CountryPrefix)
            ? me.State.Length > 0 ? me.State : me.Province
            : "001";

    /// What went out on this contact. A US or Canadian station sends the same
    /// state or province every time; everyone else sends a serial, and ARRL
    /// asks for the serial of that contact, so the Cabrillo file reads the
    /// contact's own number and not the first one. N1MM sends it unpadded.
    private string SentExchangeOn(Qso qso, StationInfo me) =>
        SendsState(me.CountryPrefix) ? SentExchangeFor(me) : $"{qso.SentNumber}";

    public int PointsFor(QsoContext qso) => qso.ModeCategory == ModeCategory.Cw ? 4 : 2;

    public IReadOnlyList<Multiplier> MultipliersFor(QsoContext qso)
    {
        string mode = qso.ModeCategory.ToString();
        string area = StatesAndProvinces.ArrlDxArea(qso.Qso.Section);
        if (StatesAndProvinces.ArrlDxMultipliers.Contains(area))
        {
            return [new Multiplier(1, area, mode)];
        }
        return qso.CountryPrefix.Length == 0 ? [] : [new Multiplier(2, qso.CountryPrefix, mode)];
    }

    public int TotalScore(ScoreTally tally, ContestEntry entry) =>
        tally.Points * tally.TotalMultipliers;

    public CabrilloExchange CabrilloExchange(Qso qso, StationInfo me, ContestEntry entry) =>
        new(
            [
                new CabrilloField(me.Callsign, 13),
                new CabrilloField(qso.SentReport, 3),
                new CabrilloField(SentExchangeOn(qso, me), 6),
            ],
            [
                new CabrilloField(qso.Call.Text, 13),
                new CabrilloField(qso.ReceivedReport, 3),
                new CabrilloField(qso.Section.Length > 0 ? qso.Section : qso.Exchange1, 6),
            ]);

    /// The states and provinces of the US, Canada and Mexico are the exchange;
    /// the rest of the world sends a number.
    private static bool SendsState(string countryPrefix) => countryPrefix is "K" or "VE" or "XE";
}