using Nonemm.Core;

namespace Nonemm.Spotting.Tests;

public class BandmapTests
{
    private static readonly DateTime Now = new(2026, 5, 30, 12, 0, 0, DateTimeKind.Utc);

    private static Spot At(string call, double kilohertz, DateTime? at = null) =>
        new(Callsign.Parse(call), Frequency.FromKilohertz(kilohertz), at ?? Now, SpotSource.Cluster);

    [Fact]
    public void SpotsComeBackInFrequencyOrder()
    {
        Bandmap map = new();
        map.Add(At("DL1ABC", 14_100));
        map.Add(At("JA1XYZ", 14_010));
        Assert.Equal(["JA1XYZ", "DL1ABC"], map.On(Bands.Band20M).Select(s => s.Call.Text));
    }

    [Fact]
    public void AStationThatMovesKeepsOneEntryOnItsBand()
    {
        Bandmap map = new();
        map.Add(At("DL1ABC", 14_010));
        map.Add(At("DL1ABC", 14_020));
        Spot only = Assert.Single(map.On(Bands.Band20M));
        Assert.Equal(14_020_000, only.Frequency.Hertz);
    }

    [Fact]
    public void TheSameStationOnAnotherBandIsASeparateEntry()
    {
        Bandmap map = new();
        map.Add(At("DL1ABC", 14_010));
        map.Add(At("DL1ABC", 7_010));
        Assert.Equal(2, map.All().Count);
    }

    [Fact]
    public void SpotsOlderThanAnHourAreDropped()
    {
        DateTime arriving = Now.AddHours(-2);
        Bandmap map = new(clock: () => arriving);
        map.Add(At("DL1ABC", 14_010));
        arriving = Now.AddMinutes(-5);
        map.Add(At("JA1XYZ", 14_020));

        map.DropOlderThan(Now);

        Assert.Equal("JA1XYZ", Assert.Single(map.All()).Call.Text);
    }

    /// Nodes get their clocks wrong and replay their backlog on connect. Age is
    /// counted from when the spot arrived, so a spot stamped hours ago still
    /// shows for the hour after it turned up.
    [Fact]
    public void ASpotStampedLongAgoIsKeptIfItOnlyJustArrived()
    {
        Bandmap map = new(clock: () => Now);
        map.Add(At("DL1ABC", 14_010, Now.AddHours(-4)));

        map.DropOlderThan(Now);

        Assert.Single(map.All());
    }

    [Fact]
    public void ARespottedStationStartsItsHourAgain()
    {
        DateTime arriving = Now.AddMinutes(-50);
        Bandmap map = new(clock: () => arriving);
        map.Add(At("DL1ABC", 14_010));
        arriving = Now;
        map.Add(At("DL1ABC", 14_012));

        map.DropOlderThan(Now.AddMinutes(30));

        Assert.Single(map.All());
    }

    /// N1MM's Mark button leaves this where the radio is, to say the frequency
    /// is busy.
    [Fact]
    public void AMarkIsLabelledWithTheTimeAndIsNotAStation()
    {
        Spot mark = Spot.Mark(
            Frequency.FromKilohertz(14_030),
            new DateTime(2026, 1, 1, 22, 31, 5, DateTimeKind.Utc));

        Assert.Equal("BUSY@22:31:05", mark.Call.Text);
        Assert.False(mark.IsStation);
    }

    [Fact]
    public void TheNearestSpotInsideTheWindowIsFound()
    {
        Bandmap map = new();
        map.Add(At("DL1ABC", 14_010));
        map.Add(At("JA1XYZ", 14_050));
        Assert.Equal(
            "DL1ABC",
            map.Near(Frequency.FromKilohertz(14_010.2), Frequency.FromKilohertz(0.5))?.Call.Text);
        Assert.Null(map.Near(Frequency.FromKilohertz(14_030), Frequency.FromKilohertz(0.5)));
    }
}