#region ================== Namespaces

using System;
using System.IO;
using System.Globalization;
using SlimDX;
using CodeImp.DoomBuilder.GZBuilder.Data;
using CodeImp.DoomBuilder.Geometry;

#endregion

namespace CodeImp.DoomBuilder.GZBuilder.GZDoom 
{
	internal sealed class ModeldefStructure 
	{
		private const int MAX_MODELS = 4; //maximum models per modeldef entry, zero-based

		internal ModelData Parse(ModeldefParser parser) 
		{
			string[] textureNames = new string[4];
			string[] modelNames = new string[4];
			bool[] modelsUsed = new bool[MAX_MODELS];
			string path = "";
			Vector3 scale = new Vector3(1, 1, 1);
			Vector3 offset = new Vector3();
			float angleOffset = 0;
			float pitchOffset = 0;
			float rollOffset = 0;
			bool inheritactorpitch = false; 
			bool inheritactorroll = false;

			string token;
			bool gotErrors = false;
			bool allParsed = false;

			//read modeldef structure contents
			while(!gotErrors && !allParsed && parser.SkipWhitespace(true)) 
			{
				token = parser.ReadToken();

				if (!string.IsNullOrEmpty(token)) 
				{
					token = parser.StripTokenQuotes(token).ToLowerInvariant(); //ANYTHING can be quoted...

					switch (token) 
					{
						case "path":
							parser.SkipWhitespace(true);
							path = parser.StripTokenQuotes(parser.ReadToken()).Replace("/", "\\");

							if(string.IsNullOrEmpty(path)) 
							{
								General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": expected path to model, but got '" + token + "'");
								gotErrors = true;
							}
							break;

						case "model":
							parser.SkipWhitespace(true);

							//model index
							int index;
							token = parser.StripTokenQuotes(parser.ReadToken());
							if(!int.TryParse(token, NumberStyles.Integer, CultureInfo.InvariantCulture, out index)) 
							{
								// Not numeric!
								General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": expected model index, but got '" + token + "'");
								gotErrors = true;
								break;
							}

							if(index >= MAX_MODELS) 
							{
								General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": GZDoom doesn't allow more than " + MAX_MODELS + " models per MODELDEF entry!");
								gotErrors = true;
								break;
							}

							parser.SkipWhitespace(true);

							//model path
							token = parser.StripTokenQuotes(parser.ReadToken()).ToLowerInvariant();
							if(string.IsNullOrEmpty(token)) 
							{
								General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": expected model name, but got '" + token + "'");
								gotErrors = true;
							} 
							else 
							{
								//check extension
								string fileExt = Path.GetExtension(token);
								if(string.IsNullOrEmpty(fileExt)) 
								{
									General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": model '" + token + "' won't be loaded. Models without extension are not supported by GZDoom.");
									gotErrors = true;
									break;
								}
								if(fileExt != ".md3" && fileExt != ".md2") 
								{
									General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": model '" + token + "' won't be loaded. Only MD2 and MD3 models are supported.");
									gotErrors = true;
									break;
								}

								//GZDoom allows models with identical modelIndex, it uses the last one encountered
								modelNames[index] = Path.Combine(path, token);
							}
							break;

						case "skin":
							parser.SkipWhitespace(true);

							//skin index
							int skinIndex;
							token = parser.StripTokenQuotes(parser.ReadToken());
							if(!int.TryParse(token, NumberStyles.Integer, CultureInfo.InvariantCulture, out skinIndex)) 
							{
								// Not numeric!
								General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": expected skin index, but got '" + token + "'");
								gotErrors = true;
								break;
							}

							if(skinIndex >= MAX_MODELS) 
							{
								General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": GZDoom doesn't allow more than " + MAX_MODELS + " skins per MODELDEF entry!");
								gotErrors = true;
								break;
							}

							parser.SkipWhitespace(true);

							//skin path
							token = parser.StripTokenQuotes(parser.ReadToken()).ToLowerInvariant();
							if(string.IsNullOrEmpty(token)) 
							{
								General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": expected skin name, but got '" + token + "'");
								gotErrors = true;
							} 
							else 
							{
								//check extension
								string ext = Path.GetExtension(token);
								if(Array.IndexOf(TextureData.SUPPORTED_TEXTURE_EXTENSIONS, ext) == -1) 
								{
									General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": image format '" + ext + "' is not supported!");
									textureNames[skinIndex] = TextureData.INVALID_TEXTURE;
								} 
								else 
								{
									//GZDoom allows skins with identical modelIndex, it uses the last one encountered
									textureNames[skinIndex] = Path.Combine(path, token);
								}
							}
							break;

						case "scale":
							parser.SkipWhitespace(true);
							token = parser.StripTokenQuotes(parser.ReadToken());
							if(!parser.ReadSignedFloat(token, ref scale.X)) 
							{
								// Not numeric!
								General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": expected Scale X value, but got '" + token + "'");
								gotErrors = true;
								break;
							}

							parser.SkipWhitespace(true);
							token = parser.StripTokenQuotes(parser.ReadToken());
							if(!parser.ReadSignedFloat(token, ref scale.Y)) 
							{
								// Not numeric!
								General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": expected Scale Y value, but got '" + token + "'");
								gotErrors = true;
								break;
							}

							parser.SkipWhitespace(true);
							token = parser.StripTokenQuotes(parser.ReadToken());
							if(!parser.ReadSignedFloat(token, ref scale.Z)) 
							{
								// Not numeric!
								General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": expected Scale Z value, but got '" + token + "'");
								gotErrors = true;
							}
							break;

						case "offset":
							parser.SkipWhitespace(true);
							token = parser.StripTokenQuotes(parser.ReadToken());
							if(!parser.ReadSignedFloat(token, ref offset.X)) 
							{
								// Not numeric!
								General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": expected Offset X value, but got '" + token + "'");
								gotErrors = true;
								break;
							}

							parser.SkipWhitespace(true);
							token = parser.StripTokenQuotes(parser.ReadToken());
							if(!parser.ReadSignedFloat(token, ref offset.Y)) 
							{
								// Not numeric!
								General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": expected Offset Y value, but got '" + token + "'");
								gotErrors = true;
								break;
							}

							parser.SkipWhitespace(true);
							token = parser.StripTokenQuotes(parser.ReadToken());
							if(!parser.ReadSignedFloat(token, ref offset.Z)) 
							{
								// Not numeric!
								General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": expected Offset Z value, but got '" + token + "'");
								gotErrors = true;
							}
							break;

						case "zoffset":
							parser.SkipWhitespace(true);

							token = parser.StripTokenQuotes(parser.ReadToken());
							if(!parser.ReadSignedFloat(token, ref offset.Z)) 
							{
								// Not numeric!
								General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": expected ZOffset value, but got '" + token + "'");
								gotErrors = true;
							}
							break;

						case "angleoffset":
							parser.SkipWhitespace(true);

							token = parser.StripTokenQuotes(parser.ReadToken());
							if(!parser.ReadSignedFloat(token, ref angleOffset)) 
							{
								// Not numeric!
								General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": expected AngleOffset value, but got '" + token + "'");
								gotErrors = true;
							}
							break;

						case "pitchoffset":
							parser.SkipWhitespace(true);

							token = parser.StripTokenQuotes(parser.ReadToken());
							if(!parser.ReadSignedFloat(token, ref pitchOffset)) 
							{
								// Not numeric!
								General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": expected PitchOffset value, but got '" + token + "'");
								gotErrors = true;
							}
							break;

						case "rolloffset":
							parser.SkipWhitespace(true);

							token = parser.StripTokenQuotes(parser.ReadToken());
							if(!parser.ReadSignedFloat(token, ref rollOffset)) 
							{
								// Not numeric!
								General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": expected RollOffset value, but got '" + token + "'");
								gotErrors = true;
							}
							break;

						case "inheritactorpitch":
							inheritactorpitch = true;
							break;

						case "inheritactorroll":
							inheritactorroll = true;
							break;

						case "frameindex":
						case "frame":
							//parsed all required fields. if got more than one model - find which one(s) should be displayed 
							int len = modelNames.GetLength(0);
							if(!gotErrors && len > 1) 
							{
								string spriteLump = null;
								string spriteFrame = null;

								//step back
								parser.DataStream.Seek(-token.Length - 1, SeekOrigin.Current);

								//here we check which models are used in first encountered lump and frame
								while(parser.SkipWhitespace(true)) 
								{
									token = parser.StripTokenQuotes(parser.ReadToken()).ToLowerInvariant();

									if(token == "frameindex" || token == "frame") 
									{
										bool frameIndex = (token == "frameindex");
										parser.SkipWhitespace(true);

										//should be sprite lump
										token = parser.StripTokenQuotes(parser.ReadToken()).ToLowerInvariant();

										if(string.IsNullOrEmpty(spriteLump)) 
										{
											spriteLump = token;
										} 
										else if(spriteLump != token) //got another lump
										{ 
											for(int i = 0; i < modelsUsed.Length; i++) 
											{
												if(!modelsUsed[i]) 
												{
													modelNames[i] = null;
													textureNames[i] = null;
												}
											}
											break;
										}

										parser.SkipWhitespace(true);

										//should be sprite frame
										token = parser.StripTokenQuotes(parser.ReadToken()).ToLowerInvariant();

										if(string.IsNullOrEmpty(spriteFrame)) 
										{
											spriteFrame = token;
										} 
										else if(spriteFrame != token) //got another frame
										{
											for(int i = 0; i < modelsUsed.Length; i++) 
											{
												if(!modelsUsed[i]) 
												{
													modelNames[i] = null;
													textureNames[i] = null;
												}
											}
											break;
										}

										parser.SkipWhitespace(true);

										//should be model index
										token = parser.StripTokenQuotes(parser.ReadToken());

										int modelIndex;
										if(!int.TryParse(token, NumberStyles.Integer, CultureInfo.InvariantCulture, out modelIndex)) 
										{
											// Not numeric!
											General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": expected model index, but got '" + token + "'");
											gotErrors = true;
											break;
										}

										if(modelIndex >= MAX_MODELS) 
										{
											General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": GZDoom doesn't allow more than " + MAX_MODELS + " models per MODELDEF entry!");
											gotErrors = true;
											break;
										}

										if(modelNames[modelIndex] == null) 
										{
											General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": got model index, which doesn't correspond to any defined model!");
											gotErrors = true;
											break;
										}

										modelsUsed[modelIndex] = true;

										parser.SkipWhitespace(true);

										// Should be frame name or index. Currently I have no use for it
										token = parser.StripTokenQuotes(parser.ReadToken());

										if(frameIndex) 
										{
											int frame = 0;
											if(!parser.ReadSignedInt(token, ref frame))
											{
												// Not numeric!
												General.ErrorLogger.Add(ErrorType.Error, "Error in " + parser.Source + " at line " + parser.GetCurrentLineNumber() + ": expected model frame, but got '" + token + "'");
												gotErrors = true;
												break;
											}

											// Skip the model if frame index is -1
											if(frame == -1) modelsUsed[modelIndex] = false;
										}
									} 
									else 
									{
										//must be "}", step back
										parser.DataStream.Seek(-token.Length - 1, SeekOrigin.Current);
										break;
									}
								}
							}
							allParsed = true;
							break;
					}
				}
			}

			// Find closing brace, then quit
			while (parser.SkipWhitespace(true)) 
			{
				token = parser.ReadToken();
				if (token == "}") break;
			}

			// Bail out when got errors or no models are used
			if (gotErrors || Array.IndexOf(modelsUsed, true) == -1) return null;
			
			// Classname is set in ModeldefParser
			ModelData mde = new ModelData();
			mde.InheritActorPitch = inheritactorpitch;
			mde.InheritActorRoll = inheritactorroll;
			Matrix moffset = Matrix.Translation(offset.Y, -offset.X, offset.Z); // Things are complicated in GZDoom...
			Matrix mrotation = Matrix.RotationY(-Angle2D.DegToRad(rollOffset)) * Matrix.RotationX(-Angle2D.DegToRad(pitchOffset)) * Matrix.RotationZ(Angle2D.DegToRad(angleOffset));
			mde.SetTransform(mrotation, moffset, scale);

			for(int i = 0; i < modelNames.Length; i++) 
			{
				if(!string.IsNullOrEmpty(modelNames[i]) && modelsUsed[i]) 
				{
					mde.TextureNames.Add(string.IsNullOrEmpty(textureNames[i]) ? textureNames[i] : textureNames[i].ToLowerInvariant());
					mde.ModelNames.Add(modelNames[i].ToLowerInvariant());
				}
			}

			return (mde.ModelNames.Count > 0 ? mde : null);
		}
	}
}