namespace Nonemm.Session.Tests;

public class CallStackTests
{
    [Fact]
    public void ACallThatIsNotAMultiplierGoesToTheBack()
    {
        CallStack stack = new();

        stack.Add("DL1ABC", isMultiplier: false);
        stack.Add("G4ABC", isMultiplier: false);

        Assert.Equal(["DL1ABC", "G4ABC"], stack.Calls);
    }

    [Fact]
    public void AMultiplierGoesToTheFront()
    {
        CallStack stack = new();
        stack.Add("DL1ABC", isMultiplier: false);
        stack.Add("G4ABC", isMultiplier: false);

        stack.Add("JA1XYZ", isMultiplier: true);

        Assert.Equal(["JA1XYZ", "DL1ABC", "G4ABC"], stack.Calls);
    }

    [Fact]
    public void ACallAlreadyOnTheStackIsMovedRatherThanRepeated()
    {
        CallStack stack = new();
        stack.Add("DL1ABC", isMultiplier: false);
        stack.Add("G4ABC", isMultiplier: false);

        stack.Add("DL1ABC", isMultiplier: true);

        Assert.Equal(["DL1ABC", "G4ABC"], stack.Calls);
    }

    [Fact]
    public void ACallTooShortToBeOneIsNotStacked()
    {
        CallStack stack = new();

        stack.Add("D", isMultiplier: false);

        Assert.True(stack.IsEmpty);
    }

    [Fact]
    public void TheCallsComeOffTheFront()
    {
        CallStack stack = new();
        stack.Add("DL1ABC", isMultiplier: false);
        stack.Add("G4ABC", isMultiplier: false);

        Assert.Equal("DL1ABC", stack.Next());
        Assert.Equal("G4ABC", stack.Next());
        Assert.Equal("", stack.Next());
    }

    [Fact]
    public void MoveToTopBringsACallForward()
    {
        CallStack stack = new();
        stack.Add("DL1ABC", isMultiplier: false);
        stack.Add("G4ABC", isMultiplier: false);

        stack.MoveToTop("G4ABC");

        Assert.Equal(["G4ABC", "DL1ABC"], stack.Calls);
    }

    [Fact]
    public void MoveToTopLeavesACallThatIsNotThereAlone()
    {
        CallStack stack = new();
        stack.Add("DL1ABC", isMultiplier: false);

        stack.MoveToTop("G4ABC");

        Assert.Equal(["DL1ABC"], stack.Calls);
    }

    /// The digital window's call stacking modes.
    [Fact]
    public void FirstInFirstOutKeepsTheOrderTheyArrivedIn()
    {
        CallStack stack = new() { Order = StackOrder.FirstIn };

        stack.Add("OM5M", isMultiplier: false);
        stack.Add("S53M", isMultiplier: true);

        Assert.Equal(["OM5M", "S53M"], stack.Calls);
    }

    [Fact]
    public void LastInFirstOutTakesTheNewestFirst()
    {
        CallStack stack = new() { Order = StackOrder.LastIn };

        stack.Add("OM5M", isMultiplier: false);
        stack.Add("S53M", isMultiplier: false);

        Assert.Equal(["S53M", "OM5M"], stack.Calls);
    }

    [Fact]
    public void NothingIsStackedWhenStackingIsOff()
    {
        CallStack stack = new() { Order = StackOrder.Disabled };

        stack.Add("OM5M", isMultiplier: true);

        Assert.True(stack.IsEmpty);
    }
}