using System;
using System.Collections;
using System.Collections.Generic;

using NW4RTools.Models;

namespace NW4RTools {
	public class BrresReader {
		public static ResFile LoadFile(byte[] data) {
			return new BrresReader().Load(new InputStream(data, ByteEndian.BigEndian));
		}



		private class RawStreamResDict : ResDict<InputStream> {
		}



		private ResFile File;
		private Logger Debug;
		private SortedDictionary<int, string> OffsetMap;

		private BrresReader() {
			Debug = new Logger();
			OffsetMap = new SortedDictionary<int, string>();
		}

		public ResFile Load(InputStream ins) {
			File = new ResFile();

			// Read BRRES header
			byte[] magic = ins.ReadBytes(4);
			UInt16 endian = ins.ReadUInt16();
			UInt16 version = ins.ReadUInt16();
			UInt32 fileSize = ins.ReadUInt32();
			UInt16 headerSize = ins.ReadUInt16();
			UInt16 blockCount = ins.ReadUInt16();

			File.version = version;

			// Read first block header
			byte[] blkMagic = ins.ReadBytes(4);
			UInt32 blkSize = ins.ReadUInt32();

			using (var c = Debug.Push("Root Dictionary")) {
				ReadAndParseDict(ins, ParseRootEntry);
			}


			// DONE!
			using (var c = Debug.Push("Offset Map")) {
				foreach (var e in OffsetMap) {
					Debug.Send("0x{0:X} : {1}", e.Key, e.Value);
				}
			}

			return File;
		}

		private void ParseRootEntry(string name, InputStream ins) {
			using (var c = Debug.Push(name)) {
				switch (name) {
				case "3DModels(NW4R)":
					File.Add(name, ReadAndConvertDict<Model>(ins, ConvertModelResource));
					break;
				default:
					Debug.Send("Not implemented");
					return;
				}
			}
		}

		private Model ConvertModelResource(string name, InputStream ins) {
			using (var c = Debug.Push(name)) {
				Model mdl = new Model();

				int startPos = ins.Position;

				OffsetMap.Add(startPos, "Model: " + name);

				byte[] magic = ins.ReadBytes(4);
				UInt32 size = ins.ReadUInt32();
				UInt32 version = ins.ReadUInt32();

				Debug.Send("Offset: 0x{0:X}; Size: 0x{1:X}; Version: {2}", startPos, size, version);

				Int32 resFileOffset = ins.ReadInt32();
				Int32 bytecodeOffset = ins.ReadInt32();
				Int32 nodeOffset = ins.ReadInt32();
				Int32 vtxPosOffset = ins.ReadInt32();
				Int32 vtxNrmOffset = ins.ReadInt32();
				Int32 vtxClrOffset = ins.ReadInt32();
				Int32 texCoordOffset = ins.ReadInt32();
				Int32 vtxFurVecOffset = ins.ReadInt32();
				Int32 vtxFurPosOffset = ins.ReadInt32();
				Int32 materialOffset = ins.ReadInt32();
				Int32 shaderOffset = ins.ReadInt32();
				Int32 shapeOffset = ins.ReadInt32();
				Int32 textureOffset = ins.ReadInt32();
				Int32 paletteOffset = ins.ReadInt32();
				Int32 unkOffset = ins.ReadInt32();
				Int32 nameOffset = ins.ReadInt32();

				int infoStructPos = ins.Position;
				OffsetMap.Add(infoStructPos, "Model Info Struct for: " + name);
				UInt32 infoSize = ins.ReadUInt32();
				// should be 0x40

				Int32 mdlOffset = ins.ReadInt32();
				mdl.ScaleMode = (Model.ScaleModeType)ins.ReadUInt32();
				mdl.TexMatrixMode = (Model.TexMatrixModeType)ins.ReadUInt32();
				UInt32 vtxCount = ins.ReadUInt32();
				UInt32 triCount = ins.ReadUInt32();
				UInt32 unk = ins.ReadUInt32();
				UInt32 nodeCount = ins.ReadUInt32();
				mdl.UsesNrmMtxArray = (bool)(ins.ReadByte() != 0);
				mdl.UsesTexMtxArray = (bool)(ins.ReadByte() != 0);
				ins.Skip(2);
				Int32 mtxDataOffset = ins.ReadInt32();
				mdl.Minimum = ins.ReadVec3();
				mdl.Maximum = ins.ReadVec3();


				ins.Seek(infoStructPos + mtxDataOffset);
				UInt32 mtxDataCount = ins.ReadUInt32();
				mdl.MatrixIDtoNodeID = new int[mtxDataCount];

				for (int i = 0; i < mtxDataCount; i++) {
					mdl.MatrixIDtoNodeID[i] = ins.ReadInt32();
				}



				// Load bytecode
				using (var c2 = Debug.Push("Bytecode"))
					mdl.Bytecode = ReadAndConvertDict<ByteCode>(ins.At(startPos + bytecodeOffset), ConvertModelBytecode);

				// Load nodes and fix up pointers
				StartNodeLoading();

				using (var c2 = Debug.Push("Nodes"))
					mdl.Nodes = ReadAndConvertDict<Node>(ins.At(startPos + nodeOffset), ConvertModelNode);

				FinishNodeLoading();

				// Load vertex data
				// COMMENTED OUT TO MAKE DEUBG OUTPUT CLEARER FOR NOW
								/*
				using (var c2 = Debug.Push("Vertex Position Data"))
					mdl.VtxPosData = ReadAndConvertDict<VertexPosData>(ins.At(startPos + vtxPosOffset), ConvertVtxPosData);
				using (var c2 = Debug.Push("Vertex Normal Data"))
					mdl.VtxNrmData = ReadAndConvertDict<VertexNrmData>(ins.At(startPos + vtxNrmOffset), ConvertVtxNrmData);
				using (var c2 = Debug.Push("Vertex Colour Data"))
					mdl.VtxClrData = ReadAndConvertDict<VertexClrData>(ins.At(startPos + vtxClrOffset), ConvertVtxClrData);
				using (var c2 = Debug.Push("Vertex TexCoord Data"))
					mdl.VtxTexCoordData = ReadAndConvertDict<VertexTexCoordData>(ins.At(startPos + texCoordOffset), ConvertVtxTexCoordData);
				*/

				// Load materials
		using (var c2 = Debug.Push("Materials"))
					mdl.Materials = ReadAndConvertDict<Material>(ins.At(startPos + materialOffset), ConvertModelMaterial);

				using (var c2 = Debug.Push("Shaders"))
					mdl.Shaders = ReadAndConvertDict<Shader>(ins.At(startPos + shaderOffset), ConvertModelShader);

				return mdl;
			}
		}

		private Models.ByteCode ConvertModelBytecode(string name, InputStream ins) {
			var bc = new Models.ByteCode();
			
			OffsetMap.Add(ins.Position, "ByteCode: " + name);

			while (true) {
				ByteCode.OpType op = (ByteCode.OpType)ins.ReadByte();

				switch (op) {
				case ByteCode.OpType.Done:
					bc.Instructions.Add(new ByteCode.DoneInstruction());
					return bc;

				case ByteCode.OpType.AssignNodeToParentMtx:
					var insn2 = new ByteCode.AssignNodeToParentMtxInstruction();
					insn2.NodeID = ins.ReadUInt16();
					insn2.ParentMatrixID = ins.ReadUInt16();
					bc.Instructions.Add(insn2);
					break;

				case ByteCode.OpType.BlendMatrices:
					var insn3 = new ByteCode.BlendMatricesInstruction();
					insn3.MatrixID = ins.ReadUInt16();
					insn3.BlendedMatrices = new ByteCode.BlendMatricesInstruction.BlendedMatrix[ins.ReadByte()];
					for (int i = 0; i < insn3.BlendedMatrices.Length; i++) {
						insn3.BlendedMatrices[i].MatrixID = ins.ReadUInt16();
						insn3.BlendedMatrices[i].Ratio = ins.ReadFloat();
					}
					bc.Instructions.Add(insn3);
					break;

				case ByteCode.OpType.DrawShape:
					var insn4 = new ByteCode.DrawShapeInstruction();
					insn4.MaterialID = ins.ReadUInt16();
					insn4.ShapeID = ins.ReadUInt16();
					insn4.NodeID = ins.ReadUInt16();
					ins.Skip(1);
					bc.Instructions.Add(insn4);
					break;

				case ByteCode.OpType.AssignMtxToNode:
					var insn5 = new ByteCode.AssignMtxToNodeInstruction();
					insn5.MatrixID = ins.ReadUInt16();
					insn5.NodeID = ins.ReadUInt16();
					bc.Instructions.Add(insn5);
					break;

				default:
					bc.Instructions.Add(new ByteCode.Instruction());
					break;
				}
			}
		}




		private class NodeLoadInfo {
			public Models.Node Node;
			public string Name;
			public int Position;
			public Int32 ParentOffset;
			public Int32 ChildOffset;
			public Int32 NextOffset;
			public Int32 PrevOffset;
		}

		private Dictionary<int, NodeLoadInfo> NodeLoadData;

		private void StartNodeLoading() {
			NodeLoadData = new Dictionary<int, NodeLoadInfo>();
		}

		private Models.Node ConvertModelNode(string name, InputStream ins) {
			var n = new Models.Node();

			OffsetMap.Add(ins.Position, "Node: " + name);

			int startPos = ins.Position;

			UInt32 size = ins.ReadUInt32();
			Int32 mdlOffset = ins.ReadInt32();
			Int32 nameOffset = ins.ReadInt32();

			n.Index = ins.ReadUInt32();
			n.MatrixID = ins.ReadUInt32();
			n.Flags = ins.ReadUInt32();
			n.BillboardMode = (Node.BillboardType)ins.ReadUInt32();
			UInt32 unk = ins.ReadUInt32();
			// might be swapped with bbmode, check asm to confirm

			n.Scale = ins.ReadVec3();
			n.Rotation = ins.ReadVec3();
			n.Translation = ins.ReadVec3();
			n.BoxMin = ins.ReadVec3();
			n.BoxMax = ins.ReadVec3();

			NodeLoadInfo loadInfo = new NodeLoadInfo();
			loadInfo.ParentOffset = ins.ReadInt32();
			loadInfo.ChildOffset = ins.ReadInt32();
			loadInfo.NextOffset = ins.ReadInt32();
			loadInfo.PrevOffset = ins.ReadInt32();
			loadInfo.Position = startPos;
			loadInfo.Node = n;
			loadInfo.Name = ins.At(startPos + nameOffset - 4).ReadName();
			NodeLoadData[startPos] = loadInfo;

			n.NodeMatrix = ins.ReadMatrix();
			n.NodeInvMatrix = ins.ReadMatrix();

			return n;
		}

		private void FinishNodeLoading() {
			foreach (var dictEntry in NodeLoadData) {
				var entry = dictEntry.Value;
				var node = entry.Node;
				
				if (entry.ParentOffset == 0) {
					node.Parent = null;
				} else {
					NodeLoadInfo n = NodeLoadData[entry.Position + entry.ParentOffset];
					node.Parent = n.Node;
					Debug.Send("Set {0}'s parent to {1}", entry.Name, n.Name);
				}

				if (entry.ChildOffset == 0)
					node.FirstChild = null;
				else
					node.FirstChild = NodeLoadData[entry.Position + entry.ChildOffset].Node;

				if (entry.NextOffset == 0)
					node.Next = null;
				else
					node.Next = NodeLoadData[entry.Position + entry.NextOffset].Node;
				
				if (entry.PrevOffset == 0)
					node.Previous = null;
				else
					node.Previous = NodeLoadData[entry.Position + entry.PrevOffset].Node;
			}

			NodeLoadData = null;
		}




		private void LoadVertexDataBase(InputStream ins, Models.VertexDataBase n) {
			UInt32 size = ins.ReadUInt32();

			Int32 mdlOffset = ins.ReadInt32();
			Int32 dataOffset = ins.ReadInt32();
			Int32 nameOffset = ins.ReadInt32();

			n.Index = ins.ReadUInt32();
			n.ComponentCount = ins.ReadUInt32();
			n.ComponentType = ins.ReadUInt32();
			n.Fraction = ins.ReadByte();
			n.EntrySize = ins.ReadByte();
			n.EntryCount = ins.ReadUInt16();

			n.Data = ins.ReadBytes(n.EntrySize * n.EntryCount);
		}

		private Models.VertexPosData ConvertVtxPosData(string name, InputStream ins) {
			var n = new Models.VertexPosData();

			OffsetMap.Add(ins.Position, "VertexPosData: " + name);

			LoadVertexDataBase(ins, n);

			n.Minimum = ins.ReadVec3();
			n.Maximum = ins.ReadVec3();

			return n;
		}

		private Models.VertexNrmData ConvertVtxNrmData(string name, InputStream ins) {
			var n = new Models.VertexNrmData();

			OffsetMap.Add(ins.Position, "VertexNrmData: " + name);

			LoadVertexDataBase(ins, n);

			return n;
		}

		private Models.VertexClrData ConvertVtxClrData(string name, InputStream ins) {
			var n = new Models.VertexClrData();

			OffsetMap.Add(ins.Position, "VertexClrData: " + name);

			LoadVertexDataBase(ins, n);

			return n;
		}

		private Models.VertexTexCoordData ConvertVtxTexCoordData(string name, InputStream ins) {
			var n = new Models.VertexTexCoordData();

			OffsetMap.Add(ins.Position, "VertexTexCoordData: " + name);

			LoadVertexDataBase(ins, n);

			n.Minimum = ins.ReadVec2();
			n.Maximum = ins.ReadVec2();

			return n;
		}



		private Models.Material ConvertModelMaterial(string name, InputStream ins) {
			Debug.Send("Reading {0}...", name);

			var m = new Models.Material();

			int startPos = ins.Position;
			OffsetMap.Add(ins.Position, "Material: " + name);

			UInt32 size = ins.ReadUInt32();
			Int32 mdlOffset = ins.ReadInt32();
			Int32 nameOffset = ins.ReadInt32();
			m.Index = ins.ReadUInt32();
			m.Flags = ins.ReadUInt32();

			// ResGenMode
			m.TexCoordGenCount = ins.ReadByte();
			m.ChanCount = ins.ReadByte();
			m.TevStageCount = ins.ReadByte();
			m.IndStageCount = ins.ReadByte();
			m.CullMode = ins.ReadUInt32();

			// ResMatMisc
			m.ZCompLoc = ins.ReadByte();
			m.LightSetID = ins.ReadByte();
			m.FogID = ins.ReadByte();

			m.IndirectTexMtxCalcMethod1 = ins.ReadBytes(4);
			m.IndirectTexMtxCalcMethod2 = ins.ReadBytes(4);
			ins.Skip(1);

			// Other stuff
			// Shader offset points to an entry in the Shaders group, must fix this up later
			// like I did with Node classes
			Int32 shaderOffset = ins.ReadInt32();
			//Debug.Send("Shader offset for {0}: {1:X} [dest {2:X}]", name, shaderOffset, startPos + shaderOffset);

			UInt32 boundTexCount = ins.ReadUInt32();
			Int32 boundTexOffset = ins.ReadInt32();

			Int32 furOffset = ins.ReadInt32();
			Debug.Send("Fur offset for {0}: {1:X} [dest {2:X}]", name, furOffset, startPos + furOffset);

			Int32 unkOffset = ins.ReadInt32();
			Debug.Send("Unknown offset for {0}: {1:X} [dest {2:X}]", name, unkOffset, startPos + unkOffset);

			// Need to implement DLs...
			Int32 dlOffset = ins.ReadInt32();
			Debug.Send("DL offset for {0}: {1:X} [dest {2:X}]", name, dlOffset, startPos + dlOffset);

			// ResTexObj
			int ResTexObjPos = ins.Position;
			OffsetMap.Add(ins.Position, "Material ResTexObj: " + name);

			UInt32 textureFlag = ins.ReadUInt32();
			m.TexObj = new byte[8][];

			for (int i = 0; i < 8; i++) {
				if ((textureFlag & (1 << i)) != 0) {
					m.TexObj[i] = ins.ReadBytes(0x20);
				}
			}

			ins.Seek(ResTexObjPos + 0x104);

			// ResTlutObj
			int ResTlutObjPos = ins.Position;
			OffsetMap.Add(ins.Position, "Material ResTlutObj: " + name);

			UInt32 tlutFlag = ins.ReadUInt32();
			if ((tlutFlag & 0xFC) == 0) {
				m.TlutObj = ins.ReadBytes(0x20);
			} else if ((tlutFlag & 0xE0) == 0) {
				m.TlutObj = ins.ReadBytes(0x40);
			} else {
				m.TlutObj = ins.ReadBytes(0x60);
			}

			ins.Seek(ResTlutObjPos + 0x64);

			// ResTexSrt
			int ResTexSrtPos = ins.Position;
			OffsetMap.Add(ins.Position, "Material ResTexSrt: " + name);

			UInt32 srtFlag = ins.ReadUInt32();
			m.TexMatrixType = ins.ReadUInt32();

			m.SRTSettings = new SRTSettingInfo[8];
			InputStream texSrtStream = ins.At(ins.Position);
			InputStream texSetStream = ins.At(ins.Position + (0x14 * 8));

			for (int i = 0; i < 8; i++) {
				if ((srtFlag & (0xF << (i * 4))) != 0) {
					var srtInfo = m.SRTSettings[i] = new SRTSettingInfo();

					srtInfo.ScaleX = texSrtStream.ReadFloat();
					srtInfo.ScaleY = texSrtStream.ReadFloat();
					srtInfo.Rotate = texSrtStream.ReadFloat();
					srtInfo.TranslateX = texSrtStream.ReadFloat();
					srtInfo.TranslateY = texSrtStream.ReadFloat();

					srtInfo.CameraID = texSetStream.ReadByte();
					srtInfo.LightID = texSetStream.ReadByte();
					srtInfo.MapType = texSetStream.ReadByte();
					srtInfo.Flags = texSetStream.ReadByte();
					srtInfo.TexMatrix = texSetStream.ReadMatrix();
				}
			}

			ins.Seek(ResTexSrtPos + 8 + (0x14 * 8) + (0x34 * 8));

			// ResMatChan
			OffsetMap.Add(ins.Position, "Material ResMatChan: " + name);

			m.ChanCtrls = new ChanCtrl[2];

			for (int i = 0; i < 2; i++) {
				var chanInfo = m.ChanCtrls[i] = new ChanCtrl();

				chanInfo.Flags = ins.ReadUInt32();
				chanInfo.MatColor = ins.ReadColor();
				chanInfo.AmbColor = ins.ReadColor();
				chanInfo.FlagC = ins.ReadUInt32();
				chanInfo.FlagA = ins.ReadUInt32();
			}

			// Bound Textures
			if (boundTexOffset != 0)
				OffsetMap.Add(startPos + boundTexOffset, "Material Bound Textures: " + name);

			ins.Seek(startPos + boundTexOffset);
			m.BoundTextures = new List<BoundTextureInfo>((int)boundTexCount);

			for (int i = 0; i < boundTexCount; i++) {
				//Debug.Send("Reading {0} bound texture at {1:X}", i, ins.Position);

				int bPos = ins.Position;
				var bTex = new BoundTextureInfo();
				m.BoundTextures.Add(bTex);

				Int32 texOffs = ins.ReadInt32();
				bTex.TextureName = texOffs == 0 ? null : ins.At(bPos + texOffs - 4).ReadName();
				Int32 palOffs = ins.ReadInt32();
				bTex.PaletteName = palOffs == 0 ? null : ins.At(bPos + palOffs - 4).ReadName();

				//Debug.Send("<{0}> <{1}>", bTex.TextureName, bTex.PaletteName);

				// placeholder pointers, don't need these
				ins.Skip(8);

				bTex.TexMapID = ins.ReadUInt32();
				bTex.TlutID = ins.ReadUInt32();
				bTex.WrapS = ins.ReadUInt32();
				bTex.WrapT = ins.ReadUInt32();
				bTex.MinFilt = ins.ReadUInt32();
				bTex.MagFilt = ins.ReadUInt32();
				bTex.LODBias = ins.ReadFloat();
				bTex.MaxAniso = ins.ReadUInt32();
				bTex.BiasClamp = (ins.ReadByte() != 0);
				bTex.DoEdgeLOD = (ins.ReadByte() != 0);
				ins.Skip(2);
			}

			return m;
		}



		private Models.Shader ConvertModelShader(string name, InputStream ins) {
			var s = new Models.Shader();

			//Debug.Send("{0} @ {1:X}", name, ins.Position);
			int startPos = ins.Position;

			// Note: duplicate shader entries seem to be common, so OffsetMap.Add can't be used
			// Looks like Nintendo's converter checks for them when writing and optimises them
			// into one entry. That'll sure be fun to implement here... probably requiring
			// messing around with IEqualityComparer or whatever it's called. I don't even know
			// if I'm making sense or not. Too tired to look it up, it's 4:51am...
			OffsetMap[ins.Position] = "Shader: " + name;

			return s;
		}




		private RawStreamResDict ReadDict(InputStream ins) {
			RawStreamResDict output = new RawStreamResDict();
			int dictPos = ins.Position;

			UInt32 dataSize = ins.ReadUInt32();
			UInt32 entryCount = ins.ReadUInt32();

			for (int i = 0; i <= entryCount; i++) {
				UInt16 eRef = ins.ReadUInt16();
				UInt16 flag = ins.ReadUInt16();
				UInt16 iLeft = ins.ReadUInt16();
				UInt16 iRight = ins.ReadUInt16();
				Int32 nameOffset = ins.ReadInt32();
				Int32 dataOffset = ins.ReadInt32();

				//Debug.Send("Position: {6:X}, eRef: {0:X}, flag: {1:X}, iLeft: {2:X}, iRight: {3:X}, nameOffset: {4:X}, dataOffset: {5:X}", eRef, flag, iLeft, iRight, nameOffset, dataOffset, ins.Position);

				if (nameOffset != 0 && dataOffset != 0) {
					string name = ins.At(dictPos + nameOffset - 4).ReadName();
					Debug.Send("Entry: {0} at offset 0x{1:X}", name, dictPos + dataOffset);

					InputStream entryStream = ins.At(dictPos + dataOffset);
					output.Add(name, entryStream);
				}
			}

			return output;
		}



		private delegate void ParseResourceDelegate(string name, InputStream ins);
		private delegate TValue ConvertResourceDelegate<TValue>(string name, InputStream ins);

		private void ReadAndParseDict(InputStream ins, ParseResourceDelegate func) {
			ReadAndParseDict(ins, func, "Unnamed");
		}

		private void ReadAndParseDict(InputStream ins, ParseResourceDelegate func, string dictName) {
			int dictPos = ins.Position;
			RawStreamResDict theDict = ReadDict(ins);
			OffsetMap.Add(dictPos, string.Format("ResDict: {0} [Data ends at 0x{1:X}]", dictName, ins.Position));

			foreach (var entry in theDict) {
				func(entry.Key, entry.Value);
			}
		}

		private ResDict<TValue> ReadAndConvertDict<TValue>(InputStream ins, ConvertResourceDelegate<TValue> func) {
			int dictPos = ins.Position;
			RawStreamResDict theDict = ReadDict(ins);
			var outDict = new ResDict<TValue>();

			// Hack to get the type name
			string valueTypeName = outDict.GetType().GetGenericArguments()[0].ToString();

			OffsetMap.Add(dictPos, string.Format("ResDict: {0} [Data ends at 0x{1:X}]", valueTypeName, ins.Position));

			foreach (var entry in theDict) {
				TValue returnedObject = func(entry.Key, entry.Value);
				outDict.Add(entry.Key, returnedObject);
			}

			return outDict;
		}
	}
}