using System.Buffers.Binary;
using Server.Items;
using Server.Network;
using Xunit;

namespace Server.Tests.Network;

[Collection("Sequential Server Tests")]
public class ContainerPacketTests
{
    [Fact]
    public void TestContainerDisplay()
    {
        var serial = (Serial)0x1024;
        ushort gumpId = 100;

        var expected = new ContainerDisplay(serial, gumpId).Compile();

        using var ns = PacketTestUtilities.CreateTestNetState();
        ns.SendDisplayContainer(serial, gumpId);

        var result = ns.SendBuffer.GetReadSpan();
        AssertThat.Equal(result, expected);
    }

    [Fact]
    public void TestContainerDisplayHS()
    {
        var serial = (Serial)0x1024;
        ushort gumpId = 100;

        var expected = new ContainerDisplayHS(serial, gumpId).Compile();

        using var ns = PacketTestUtilities.CreateTestNetState();
        ns.ProtocolChanges = ns.ProtocolChanges | ProtocolChanges.ContainerGridLines | ProtocolChanges.HighSeas;
        ns.SendDisplayContainer(serial, gumpId);

        var result = ns.SendBuffer.GetReadSpan();
        AssertThat.Equal(result, expected);
    }

    [Fact]
    public void TestDisplaySpellbook()
    {
        var serial = (Serial)0x1024;

        var expected = new DisplaySpellbook(serial).Compile();

        using var ns = PacketTestUtilities.CreateTestNetState();
        ns.SendDisplaySpellbook(serial);

        var result = ns.SendBuffer.GetReadSpan();
        AssertThat.Equal(result, expected);
    }

    [Fact]
    public void TestDisplaySpellbookHS()
    {
        var serial = (Serial)0x1024;

        var expected = new DisplaySpellbookHS(serial).Compile();

        using var ns = PacketTestUtilities.CreateTestNetState();
        ns.ProtocolChanges = ns.ProtocolChanges | ProtocolChanges.ContainerGridLines | ProtocolChanges.HighSeas;
        ns.SendDisplaySpellbook(serial);

        var result = ns.SendBuffer.GetReadSpan();
        AssertThat.Equal(result, expected);
    }

    [Fact]
    public void TestNewSpellbookContent()
    {
        var serial = (Serial)0x1024;
        ushort graphic = 100;
        ushort offset = 10;
        ulong content = 0x123456789ABCDEF0;
        var opl = ObjectPropertyList.Enabled;

        var expected = new NewSpellbookContent(serial, graphic, offset, content).Compile();

        using var ns = PacketTestUtilities.CreateTestNetState();
        ns.ProtocolChanges = ns.ProtocolChanges | ProtocolChanges.ContainerGridLines | ProtocolChanges.NewSpellbook;
        ObjectPropertyList.Enabled = true;
        ns.SendSpellbookContent(serial, graphic, offset, content);
        ObjectPropertyList.Enabled = opl;

        var result = ns.SendBuffer.GetReadSpan();
        AssertThat.Equal(result, expected);
    }

    [Fact]
    public void TestSpellbookContent()
    {
        var serial = (Serial)0x1024;
        ushort offset = 10;
        ushort graphic = 100;
        ulong content = 0x123456789ABCDEF0;

        var expected = new SpellbookContent(serial, offset, content).Compile();

        using var ns = PacketTestUtilities.CreateTestNetState();
        ns.SendSpellbookContent(serial, graphic, offset, content);

        var result = ns.SendBuffer.GetReadSpan();
        AssertThat.Equal(result, expected);
    }

    [Fact]
    public void TestSpellbookContent6017()
    {
        var serial = (Serial)0x1024;
        ushort offset = 10;
        ushort graphic = 100;
        ulong content = 0x123456789ABCDEF0;

        var expected = new SpellbookContent6017(serial, offset, content).Compile();

        using var ns = PacketTestUtilities.CreateTestNetState();
        ns.ProtocolChanges |= ProtocolChanges.ContainerGridLines;
        ns.SendSpellbookContent(serial, graphic, offset, content);

        var result = ns.SendBuffer.GetReadSpan();
        AssertThat.Equal(result, expected);
    }

    [Fact]
    public void TestContainerContentUpdate()
    {
        var serial = (Serial)0x1024;
        var item = new Item(serial);

        var expected = new ContainerContentUpdate(item).Compile();

        using var ns = PacketTestUtilities.CreateTestNetState();
        ns.SendContainerContentUpdate(item);

        var result = ns.SendBuffer.GetReadSpan();
        AssertThat.Equal(result, expected);
    }

    [Fact]
    public void TestContainerContentUpdate6017()
    {
        var serial = (Serial)0x1024;
        var item = new Item(serial);

        var expected = new ContainerContentUpdate6017(item).Compile();

        using var ns = PacketTestUtilities.CreateTestNetState();
        ns.ProtocolChanges |= ProtocolChanges.ContainerGridLines;
        ns.SendContainerContentUpdate(item);

        var result = ns.SendBuffer.GetReadSpan();
        AssertThat.Equal(result, expected);
    }

    [Fact]
    public void TestContainerContent()
    {
        var cont = new Container(World.NewItem);
        cont.AddItem(new Item(World.NewItem));
        cont.Map = Map.Felucca;

        var m = new Mobile((Serial)0x1);
        m.DefaultMobileInit();
        m.AccessLevel = AccessLevel.Administrator;
        m.Map = Map.Felucca;

        var expected = new ContainerContent(m, cont).Compile();

        using var ns = PacketTestUtilities.CreateTestNetState();
        ns.SendContainerContent(m, cont);

        var result = ns.SendBuffer.GetReadSpan();
        AssertThat.Equal(result, expected);
    }

    [Fact]
    public void TestContainerContent6017()
    {
        var cont = new Container(World.NewItem);
        cont.AddItem(new Item(World.NewItem));
        cont.Map = Map.Felucca;

        var m = new Mobile((Serial)0x1);
        m.DefaultMobileInit();
        m.AccessLevel = AccessLevel.Administrator;
        m.Map = Map.Felucca;

        var expected = new ContainerContent6017(m, cont).Compile();

        using var ns = PacketTestUtilities.CreateTestNetState();
        ns.ProtocolChanges |= ProtocolChanges.ContainerGridLines;
        ns.SendContainerContent(m, cont);

        var result = ns.SendBuffer.GetReadSpan();
        AssertThat.Equal(result, expected);
    }

    [Fact]
    public void TestContainerContent_CapsAtProtocolLimit()
    {
        var cont = new Container(World.NewItem);

        // Past the 3448-entry cap (19-byte entries) so truncation engages.
        const int itemCount = 5000;
        for (var i = 0; i < itemCount; i++)
        {
            cont.AddItem(new Item(World.NewItem));
        }

        cont.Map = Map.Felucca;

        var m = new Mobile((Serial)0x1);
        m.DefaultMobileInit();
        m.AccessLevel = AccessLevel.Administrator;
        m.Map = Map.Felucca;

        try
        {
            using var ns = PacketTestUtilities.CreateTestNetState();
            // A ~64KB packet exceeds the 4KB pre-auth send buffer; an account lets Send() promote it
            // on demand instead of exhausting the buffer and disconnecting.
            ns.Account = new MockAccount();

            var ex = Record.Exception(() => ns.SendContainerContent(m, cont));
            Assert.Null(ex);

            var span = ns.SendBuffer.GetReadSpan();
            Assert.Equal((byte)0x3C, span[0]);

            var length = BinaryPrimitives.ReadUInt16BigEndian(span[1..3]);
            var count = BinaryPrimitives.ReadUInt16BigEndian(span[3..5]);

            const int entrySize = 19; // no grid lines negotiated on this NetState
            var expectedMaxEntries = (ushort.MaxValue - 5) / entrySize;

            Assert.Equal(65517, length);
            Assert.Equal(length, span.Length);
            Assert.Equal(expectedMaxEntries, count);
        }
        finally
        {
            cont.Delete();
            m.Delete();
        }
    }

    [Fact]
    public void TestContainerContent_CapsAtProtocolLimit_WithGridLines()
    {
        var cont = new Container(World.NewItem);

        // Past the 3276-entry cap (20-byte entries with grid lines) so truncation engages.
        const int itemCount = 5000;
        for (var i = 0; i < itemCount; i++)
        {
            cont.AddItem(new Item(World.NewItem));
        }

        cont.Map = Map.Felucca;

        var m = new Mobile((Serial)0x1);
        m.DefaultMobileInit();
        m.AccessLevel = AccessLevel.Administrator;
        m.Map = Map.Felucca;

        try
        {
            using var ns = PacketTestUtilities.CreateTestNetState();
            ns.ProtocolChanges |= ProtocolChanges.ContainerGridLines;
            ns.Account = new MockAccount();

            var ex = Record.Exception(() => ns.SendContainerContent(m, cont));
            Assert.Null(ex);

            var span = ns.SendBuffer.GetReadSpan();
            Assert.Equal((byte)0x3C, span[0]);

            var length = BinaryPrimitives.ReadUInt16BigEndian(span[1..3]);
            var count = BinaryPrimitives.ReadUInt16BigEndian(span[3..5]);

            Assert.Equal(65525, length);
            Assert.Equal(length, span.Length);
            Assert.Equal(3276, count);
        }
        finally
        {
            cont.Delete();
            m.Delete();
        }
    }

    [Fact]
    public void TestContainerContent_RentedBuffer_MatchesReferencePacket()
    {
        var cont = new Container(World.NewItem);

        // Below the entry cap but past the 1024-byte stackalloc threshold, so SendContainerContent
        // rents its buffer instead of using the stack.
        const int itemCount = 100;
        for (var i = 0; i < itemCount; i++)
        {
            cont.AddItem(new Item(World.NewItem));
        }

        cont.Map = Map.Felucca;

        var m = new Mobile((Serial)0x1);
        m.DefaultMobileInit();
        m.AccessLevel = AccessLevel.Administrator;
        m.Map = Map.Felucca;

        try
        {
            var expected = new ContainerContent(m, cont).Compile();

            using var ns = PacketTestUtilities.CreateTestNetState();
            ns.SendContainerContent(m, cont);

            var result = ns.SendBuffer.GetReadSpan();
            AssertThat.Equal(result, expected);
        }
        finally
        {
            cont.Delete();
            m.Delete();
        }
    }
}