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

namespace Nonemm.Contests.Rules;

/// ARRL International DX, CW and SSB. W and VE stations work DX and nobody
/// else, so the exchange and the multiplier both depend on which side the
/// operator is on.
///
/// The received power or state goes in the section column, which is where N1MM
/// keeps it, so a log written by either program scores the same in the other.
public sealed class ArrlDx : Contest
{
    private readonly ModeCategory mode;

    public ArrlDx(ModeCategory mode) => this.mode = mode;

    public string Name => mode == ModeCategory.Cw ? "ARRLDXCW" : "ARRLDXSSB";

    public string DisplayName => $"ARRL International DX {ModeLabel()}";

    public string CabrilloName => mode == ModeCategory.Cw ? "ARRL-DX-CW" : "ARRL-DX-SSB";

    /// A W or VE operator copies the power the DX station sends, which goes in
    /// the power column; a DX operator copies a state or province, which goes
    /// in the section column. Both are where N1MM keeps them.
    public IReadOnlyList<ExchangeField> ExchangeFieldsFor(StationInfo me) =>
    [
        new ExchangeField("Snt", ExchangeSlot.SentReport, ExchangeFieldKind.Report, IsRequired: false),
        new ExchangeField("Rcv", ExchangeSlot.ReceivedReport, ExchangeFieldKind.Report),
        IsNorthAmericanHome(me)
            ? new ExchangeField("Pwr", ExchangeSlot.Power, ExchangeFieldKind.Power)
            : new ExchangeField("State", ExchangeSlot.Section, ExchangeFieldKind.UsStateOrCanadianProvince),
    ];

    public IReadOnlyList<string> MultiplierNamesFor(StationInfo me) => ["Mults"];

    public DupeScope DupeScope => DupeScope.PerBand;

    public bool HasSerialNumbers => false;

    public IReadOnlyList<ModeCategory> Modes => [mode];

    public string SentExchangeFor(StationInfo me) =>
        IsNorthAmericanHome(me) ? StateOrProvince(me) : me.Power;

    /// Only contacts across the W/VE line count, so a DX station working DX or
    /// a W station working W scores nothing.
    public int PointsFor(QsoContext qso) =>
        IsNorthAmericanHome(qso.Me) == IsNorthAmerican(qso.CountryPrefix) ? 0 : 3;

    public IReadOnlyList<Multiplier> MultipliersFor(QsoContext qso)
    {
        if (PointsFor(qso) == 0)
        {
            return [];
        }
        string band = qso.Band?.Name ?? "";
        if (IsNorthAmericanHome(qso.Me))
        {
            return qso.CountryPrefix.Length == 0 ? [] : [new Multiplier(1, qso.CountryPrefix, band)];
        }
        string received = StatesAndProvinces.ArrlDxArea(qso.Qso.Section);
        return StatesAndProvinces.ArrlDxMultipliers.Contains(received)
            ? [new Multiplier(1, received, band)]
            : [];
    }

    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(IsNorthAmericanHome(me) ? StateOrProvince(me) : me.Power, 6),
            ],
            [
                new CabrilloField(qso.Call.Text, 13),
                new CabrilloField(qso.ReceivedReport, 3),
                new CabrilloField(IsNorthAmericanHome(me) ? qso.Power : qso.Section, 6),
            ]);

    private static bool IsNorthAmericanHome(StationInfo me) => IsNorthAmerican(me.CountryPrefix);

    /// The contest's W/VE side is the 48 states, DC and Canada; KH6 and KL7
    /// count as DX for it.
    private static bool IsNorthAmerican(string countryPrefix) =>
        countryPrefix is "K" or "VE";

    private static string StateOrProvince(StationInfo me) =>
        me.State.Length > 0 ? me.State : me.Province;

    private string ModeLabel() => mode == ModeCategory.Cw ? "CW" : "SSB";

}