// Copyright Dirk Lemstra https://github.com/dlemstra/Magick.NET.
// Licensed under the Apache License, Version 2.0.

using ImageMagick;
using Xunit;

namespace Magick.NET.Core.Tests;

public partial class EndianReaderTests
{
    public class TheReadDoubleMethod : EndianReaderTests
    {
        [Fact]
        public void ShouldReturnNullWhenBufferIsNotLongEnough()
        {
            var reader = new EndianReader(new byte[1] { 0 });
            reader.IsLittleEndian = true;

            var result = reader.ReadDouble();

            Assert.Null(result);
        }

        [Fact]
        public void ShouldReadDoubleBigEndian()
        {
            var reader = new EndianReader(new byte[8] { 64, 181, 58, 229, 96, 65, 137, 55 });

            var result = reader.ReadDouble();

            Assert.Equal(5434.896, result);
        }

        [Fact]
        public void ShouldReadDoubleLittleEndian()
        {
            var reader = new EndianReader(new byte[8] { 55, 137, 65, 96, 229, 58, 181, 64 });
            reader.IsLittleEndian = true;

            var result = reader.ReadDouble();

            Assert.Equal(5434.896, result);
        }

        [Fact]
        public void ShouldChangeTheIndex()
        {
            var reader = new EndianReader(new byte[8] { 0, 0, 0, 0, 0, 0, 0, 0 });
            reader.IsLittleEndian = true;

            reader.ReadDouble();

            Assert.Equal(8U, reader.Index);
        }
    }
}
