using System;
using System.Runtime.InteropServices;
using System.Text;

using BizHawk.Common.NumberExtensions;
using BizHawk.Emulation.Common;
using BizHawk.Emulation.Cores.Nintendo.N64.NativeApi;

namespace BizHawk.Emulation.Cores.Nintendo.N64
{
	partial class N64
	{
		public TraceBuffer Tracer { get; private set; }

		private mupen64plusApi.TraceCallback _tracecb;

		public void MakeTrace()
		{
			var regs = GetCpuFlagsAndRegisters();
			uint pc = (uint)regs["PC"].Value;
			var length = 0;
			var disasm = Disassemble(MemoryDomains.SystemBus, pc, out length);

			var traceInfo = new TraceInfo
			{
				Disassembly = string.Format("{0:X}:  {1}", pc, disasm.PadRight(32))
			};

			var sb = new StringBuilder();

			for (int i = 1; i < 32; i++) // r0 is always zero
			{
				UInt64 val = (regs["REG" + i + "_hi"].Value << 32) | regs["REG" + i + "_lo"].Value;
				string name = GPRnames[i];
				sb.Append(string.Format("{0}:{1:X16} ", name, val));
			}

			sb.Append(string.Format("LL:{0:X8} ", regs["LL"].Value));
			sb.Append(string.Format("LO:{0:X8}{1:X8} ", regs["LO_hi"].Value, regs["LO_lo"].Value));
			sb.Append(string.Format("HI:{0:X8}{1:X8} ", regs["HI_hi"].Value, regs["HI_lo"].Value));
			sb.Append(string.Format("FCR0:{0:X8} ", regs["FCR0"].Value));
			sb.Append(string.Format("FCR31:{0:X8} ", regs["FCR31"].Value));

			for (int i = 0; i < 32; i++) // r0 is always zero
			{
				UInt64 val = (regs["CP1 FGR REG" + i + "_hi"].Value << 32) | regs["CP1 FGR REG" + i + "_lo"].Value;
				sb.Append(string.Format("f{0}:{1:X16} ", i, val));
			}

			// drop MMU co-processor regs for now

			traceInfo.RegisterInfo = sb.ToString().Trim();

			Tracer.Put(traceInfo);
		}

		private const string TraceHeader = "r3400: PC, mnemonic, operands, registers (GPRs, Load/Link Bit, MultHI, MultLO, Implementation/Revision, Control/Status, FGRs)";

		private void ConnectTracer()
		{
			Tracer = new TraceBuffer { Header = TraceHeader };
			(ServiceProvider as BasicServiceProvider).Register<ITraceable>(Tracer);
			_tracecb = new mupen64plusApi.TraceCallback(MakeTrace);
		}

		private string[] GPRnames = new string[32]
		{
			"r0",
			"at",
			"v0", "v1",
			"a0", "a1", "a2", "a3",
			"t0", "t1", "t2", "t3", "t4", "t5", "t6", "t7",
			"s0", "s1", "s2", "s3", "s4", "s5", "s6", "s7",
			"t8", "t9",
			"k0", "k1",
			"gp",
			"sp",
			"s8",
			"ra"
		};
	}
}