using System;
using System.Linq;
using Skeleton.DataStructure.Link;

namespace Skeleton.Test;
[TestFixture]
public class LinkTest : BaseTest
{
    private class TestObj
    {
        public TestObj(int val) => Value = val;
        public int Value { get; set; } = 0;
    }
    
    [Test]
    public static void Test()
    {
        Link<int> obj = new Link<int>();
        for (int i = 0; i <= 10; i++)
            obj.AddLast(i);
        int checker = 0;
        foreach (int val in obj)
            Assert.That(checker++, Is.EqualTo(val));

        checker -= 1;
        foreach (int val in obj.Backward)
            Assert.That(checker--, Is.EqualTo(val));
        Link<TestObj> objA = new Link<TestObj>();
        for (int i = 0; i <= 10; i++)
            objA.AddLast(new TestObj(i));
        Assert.That(objA.Zip(obj).Count(x => x.First.Value - x.Second != 0), Is.EqualTo(0));
        LinkNode<TestObj> findObj = objA.Find(new TestObj(0));
        LinkNode<int> findInt = obj.Find(0);

        Assert.That(LinkNode<TestObj>.Null, Is.EqualTo(findObj));
        Assert.That(LinkNode<int>.Null, Is.Not.EqualTo(findInt));
        findObj = objA.Find(objA.First.Value);
        Assert.That(LinkNode<TestObj>.Null, Is.Not.EqualTo(findObj));
        try
        {
            objA.Remove(findObj.Previous);
            Assert.Fail();
        }
        catch (Exception)
        {
            // pass
        }

        objA.Remove(findObj.Next);
        objA.Remove(findObj.Next.Next);
        Assert.That(objA.Select(x => x.Value).Count(x => x==1 || x==3), Is.EqualTo(0));
        Assert.That(findInt.Value, Is.EqualTo(0));
        obj.Remove(findInt);
        obj.RemoveFirst();
        Assert.IsFalse(obj.Contains(0) || obj.Contains(1));
        Assert.That(findInt.Previous, Is.EqualTo(LinkNode<int>.Null));
        Assert.That(findInt.Next, Is.EqualTo(LinkNode<int>.Null));
        Assert.That(findInt.Parent, Is.EqualTo(Link<int>.Null));
        Assert.That(obj.Find(findInt.Value), Is.EqualTo(LinkNode<int>.Null));
        Console.WriteLine("Link Structure Test Pass");
    }
}