using System.Collections;
using Numbers.NumberString;

namespace Numbers.Test.NumberString;

using NumberString = Numbers.NumberString.NumberString;

public sealed class NumberStringTests
{
    [Theory]
    [InlineData("abc133", 133)]
    [InlineData("4a2b3c", 423)]
    [InlineData("1235abc", 1235)]
    [InlineData("3ab2c", 32)]
    [InlineData("abc", 0)]
    public void NumericValue(string input, int expected)
    {
        var numberString = new NumberString(input);

        numberString.NumericValue.Should().Be(expected);
    }

    [Fact]
    public void Equals_Equal()
    {
        var numberString1 = new NumberString("abc123");
        var numberString2 = new NumberString("1a2b3c");

        numberString1.Should<NumberString>().Be(numberString2);
    }

    [Fact]
    public void Equals_NotEqual()
    {
        var numberString1 = new NumberString("abc123");
        var numberString2 = new NumberString("abc124");

        numberString1.Should<NumberString>().NotBe(numberString2);
    }

    [Fact]
    public void OperatorGreater()
    {
        var numberString1 = new NumberString("abc124");
        var numberString2 = new NumberString("abc123");

        (numberString1 > numberString2).Should().BeTrue();
    }

    [Fact]
    public void OperatorLess()
    {
        var numberString1 = new NumberString("abc123");
        var numberString2 = new NumberString("abc124");

        (numberString1 < numberString2).Should().BeTrue();
    }

    [Fact]
    public void CompareTo()
    {
        var numberString1 = new NumberString("abc123");
        var numberString2 = new NumberString("abc124");
        var numberString3 = new NumberString("abc124");

        numberString1.CompareTo(numberString2).Should().BeNegative();
        numberString2.CompareTo(numberString1).Should().BePositive();
        numberString2.CompareTo(numberString3).Should().Be(0);
    }

    [Fact]
    public void Equals_Operators()
    {
        var numberString1 = new NumberString("abc123");
        var numberString2 = new NumberString("abc124");
        var numberString3 = new NumberString("abc124");

        (numberString1 == numberString2).Should().BeFalse();
        (numberString2 == numberString3).Should().BeTrue();
        (numberString1 != numberString3).Should().BeTrue();
        (numberString2 != numberString3).Should().BeFalse();
    }

    [Fact]
    public void Equals_Simple()
    {
        var numberString1 = new NumberString("abc123");
        var numberString2 = new NumberString("abc123");

        numberString1.Equals(new object()).Should().BeFalse();
        numberString1.Equals(null).Should().BeFalse();
        numberString1!.Equals(numberString2).Should().BeTrue();
    }

    [Fact]
    public void GetEnumerator()
    {
        var numberString = new NumberString("abc123");

        IEnumerator<int> enumerator = numberString.GetEnumerator();

        enumerator.Should().BeOfType<DigitEnumerator>();
        enumerator.Dispose();
    }

    [Fact]
    public void GetEnumerator_Redirect()
    {
        var numberString = new NumberString("abc123");
        IEnumerator enumerator = numberString.GetEnumerator();

        enumerator.Should().BeOfType<DigitEnumerator>();
        ((IDisposable) enumerator).Dispose();
    }

    [Fact]
    public void HashCode()
    {
        var numberString = new NumberString("abc123");

        numberString.GetHashCode().Should().Be(numberString.NumericValue);
    }

    [Fact]
    public void Indexer()
    {
        var numberString = new NumberString("5abc1de7fg34");

        numberString[0].Should().Be(5);
        numberString[2].Should().Be(7);
        numberString[4].Should().Be(4);
        numberString[-1].Should().Be(-1, "invalid index");
        numberString[5].Should().Be(-1, "invalid index (too high)");
    }
}