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

namespace Server.Tests.Network.Packets
{
  public class MessageTests
  {
    [Fact]
    public void TestMessageLocalized()
    {
      Serial serial = 0x1;
      int graphic = 0x100;
      var messageType = MessageType.Label;
      int hue = 1024;
      int font = 3;
      int number = 150000;
      string name = "Stuff";
      string args = "Arguments";

      Span<byte> data = new MessageLocalized(
        serial,
        graphic,
        messageType,
        hue,
        font,
        number,
        name,
        args
      ).Compile();

      Span<byte> expectedData = stackalloc byte[50 + args.Length * 2];
      int pos = 0;
      expectedData.Write(ref pos, (byte)0xC1); // Packet ID
      expectedData.Write(ref pos, (ushort)expectedData.Length); // Length

      expectedData.Write(ref pos, serial);
      expectedData.Write(ref pos, (ushort)graphic);
      expectedData.Write(ref pos, (byte)messageType);
      expectedData.Write(ref pos, (ushort)hue);
      expectedData.Write(ref pos, (ushort)font);
      expectedData.Write(ref pos, number);
      expectedData.WriteAsciiFixed(ref pos, name, 30);
      expectedData.WriteLittleUniNull(ref pos, args);

      AssertThat.Equal(data, expectedData);
    }

    [Fact]
    public void TestMessageLocalizedAffix()
    {
      Serial serial = 0x1;
      int graphic = 0x100;
      var messageType = MessageType.Label;
      int hue = 1024;
      int font = 3;
      int number = 150000;
      string name = "Stuff";
      string args = "Arguments";
      var affixType = AffixType.System;
      string affix = "Affix";

      Span<byte> data = new MessageLocalizedAffix(
        serial,
        graphic,
        messageType,
        hue,
        font,
        number,
        name,
        affixType,
        affix,
        args
      ).Compile();

      Span<byte> expectedData = stackalloc byte[52 + affix.Length + args.Length * 2];
      int pos = 0;
      expectedData.Write(ref pos, (byte)0xCC); // Packet ID
      expectedData.Write(ref pos, (ushort)expectedData.Length); // Length

      expectedData.Write(ref pos, serial);
      expectedData.Write(ref pos, (ushort)graphic);
      expectedData.Write(ref pos, (byte)messageType);
      expectedData.Write(ref pos, (ushort)hue);
      expectedData.Write(ref pos, (ushort)font);
      expectedData.Write(ref pos, number);
      expectedData.Write(ref pos, (byte)affixType);
      expectedData.WriteAsciiFixed(ref pos, name, 30);
      expectedData.WriteAsciiNull(ref pos, affix);
      expectedData.WriteBigUniNull(ref pos, args);

      AssertThat.Equal(data, expectedData);
    }

    [Fact]
    public void TestAsciiMessage()
    {
      Serial serial = 0x1;
      int graphic = 0x100;
      var messageType = MessageType.Label;
      int hue = 1024;
      int font = 3;
      string name = "Stuff";
      string text = "Some Text";

      Span<byte> data = new AsciiMessage(
        serial,
        graphic,
        messageType,
        hue,
        font,
        name,
        text
      ).Compile();

      Span<byte> expectedData = stackalloc byte[45 + text.Length];
      int pos = 0;
      expectedData.Write(ref pos, (byte)0x1C); // Packet ID
      expectedData.Write(ref pos, (ushort)expectedData.Length); // Length

      expectedData.Write(ref pos, serial);
      expectedData.Write(ref pos, (ushort)graphic);
      expectedData.Write(ref pos, (byte)messageType);
      expectedData.Write(ref pos, (ushort)hue);
      expectedData.Write(ref pos, (ushort)font);
      expectedData.WriteAsciiFixed(ref pos, name, 30);
      expectedData.WriteAsciiNull(ref pos, text);

      AssertThat.Equal(data, expectedData);
    }

    [Fact]
    public void TestUnicodeMessage()
    {
      Serial serial = 0x1;
      int graphic = 0x100;
      var messageType = MessageType.Label;
      int hue = 1024;
      int font = 3;
      string lang = "ENU";
      string name = "Stuff";
      string text = "Some Text";

      Span<byte> data = new UnicodeMessage(
        serial,
        graphic,
        messageType,
        hue,
        font,
        lang,
        name,
        text
      ).Compile();

      Span<byte> expectedData = stackalloc byte[50 + text.Length * 2];
      int pos = 0;
      expectedData.Write(ref pos, (byte)0xAE); // Packet ID
      expectedData.Write(ref pos, (ushort)expectedData.Length); // Length

      expectedData.Write(ref pos, serial);
      expectedData.Write(ref pos, (ushort)graphic);
      expectedData.Write(ref pos, (byte)messageType);
      expectedData.Write(ref pos, (ushort)hue);
      expectedData.Write(ref pos, (ushort)font);
      expectedData.WriteAsciiFixed(ref pos, lang, 4);
      expectedData.WriteAsciiFixed(ref pos, name, 30);
      expectedData.WriteBigUniNull(ref pos, text);

      AssertThat.Equal(data, expectedData);
    }

    [Fact]
    public void TestFollowMessage()
    {
      Serial serial = 0x1;
      Serial serial2 = 0x2;

      Span<byte> data = new FollowMessage(serial, serial2).Compile();

      Span<byte> expectedData = stackalloc byte[9];
      int pos = 0;

      expectedData.Write(ref pos, (byte)0x15); // Packet ID
      expectedData.Write(ref pos, serial);
      expectedData.Write(ref pos, serial2);

      AssertThat.Equal(data, expectedData);
    }
  }
}