Dogcows Code - chaz/carfire/blob - CarFire/CarFire/CarFire/MapReader.cs

   1 using System;
   2 using System.Collections.Generic;
   3 using System.Linq;
   4 using System.Runtime.Serialization;
   5 using Microsoft.Xna.Framework;
   6 using Microsoft.Xna.Framework.Content;
   7 using Microsoft.Xna.Framework.Graphics;
   8 using System.Reflection;
   9
  10 namespace CarFire
  11 {
  12     /// <summary>
  13     /// This class will be instantiated by the XNA Framework Content
  14     /// Pipeline to read cfmap files from binary .xnb format.
  15     /// </summary>
  16     public class MapReader : ContentTypeReader<Map>
  17     {
  18         #region Protected Methods
  19
  20         protected override Map Read(ContentReader input, Map existingInstance)
  21         {
  22             mImpl = new Impl(input);
  23             return mImpl.GetMap();
  24         }
  25
  26         #endregion
  27
  28
  29         #region Private Types
  30
  31         /// <summary>
  32         /// This private class wraps around ContentReader to make it more
  33         /// convenient to use it as an input stream reader.
  34         /// </summary>
  35         class LineReader
  36         {
  37             ContentReader mInput;
  38             int mLineNumber = 0;
  39             int mExpectedNumberOfLines;
  40
  41             public LineReader(ContentReader input)
  42             {
  43                 mInput = input;
  44                 mExpectedNumberOfLines = mInput.ReadInt32();
  45             }
  46
  47             public string ReadLine()
  48             {
  49                 mLineNumber++;
  50                 return mInput.ReadString();
  51             }
  52
  53             public int LineNumber { get { return mLineNumber; } }
  54
  55             public bool End { get { return mLineNumber >= mExpectedNumberOfLines; } }
  56         }
  57
  58
  59         /// <summary>
  60         /// This class is the actual implementation.  The implementation is wrapped
  61         /// in a subclass because the invoker seems to only be able to invoke public
  62         /// methods, and this needs to invoke methods that shouldn't be public.
  63         /// </summary>
  64         class Impl
  65         {
  66             public Impl(ContentReader input)
  67             {
  68                 mInput = new LineReader(input);
  69                 ReadSectionHeaders();
  70                 PostProcess();
  71             }
  72
  73             public Map GetMap()
  74             {
  75                 return new Map(mMetadata, mGrid, mDefaultTile, mEntities, mPlayerPositions);
  76             }
  77
  78
  79             public void ReadSectionHeaders()
  80             {
  81                 mMetadata = new Map.Metadata();
  82
  83                 while (!mInput.End)
  84                 {
  85                     string line = mInput.ReadLine();
  86
  87                     while (line != null)
  88                     {
  89                         if (!IsLineSignificant(line)) break;
  90
  91                         string section = Parse.IniSectionHeader(line);
  92                         if (section != null)
  93                         {
  94                             if (section == "metadata")
  95                             {
  96                                 line = ReadMetadataSection();
  97                             }
  98                             else if (section == "maptable")
  99                             {
 100                                 line = ReadMapTableSection();
 101                             }
 102                             else if (section.Length == 1 && IsValidEntityIdentifier(section[0]))
 103                             {
 104                                 line = ReadEntitySection(section[0]);
 105                             }
 106                             else
 107                             {
 108                                 throw new Exception("Unexpected section on line " + mInput.LineNumber + ": " + section);
 109                             }
 110                         }
 111                         else
 112                         {
 113                             throw new Exception("Unexpected text on line " + mInput.LineNumber + ": " + line);
 114                         }
 115                     }
 116                 }
 117             }
 118
 119             string ReadMetadataSection()
 120             {
 121                 while (!mInput.End)
 122                 {
 123                     string line = mInput.ReadLine();
 124                     if (!IsLineSignificant(line)) continue;
 125
 126                     string[] pair = Parse.KeyValuePair(line);
 127                     if (pair != null)
 128                     {
 129                         try
 130                         {
 131                             string methodName = "set_" + pair[0].ToLowerInvariant();
 132                             object[] args = new object[1];
 133                             args[0] = pair[1];
 134                             GetType().InvokeMember(methodName, BindingFlags.InvokeMethod, null, this, args);
 135                         }
 136 #pragma warning disable 0168
 137                         catch (System.MissingMethodException ex)
 138 #pragma warning restore 0168
 139                         {
 140                             throw new Exception("Unexpected key on line " + mInput.LineNumber + ": " + pair[0]);
 141                         }
 142                     }
 143                     else
 144                     {
 145                         return line;
 146                     }
 147                 }
 148
 149                 return null;
 150             }
 151
 152             string ReadMapTableSection()
 153             {
 154                 if (mMetadata == null || mMetadata.GridWidth == 0 || mMetadata.GridHeight == 0)
 155                 {
 156                     throw new Exception("Unexpected section on line " + mInput.LineNumber +
 157                         ": You must define the map dimensions before this section.");
 158                 }
 159
 160                 mGrid = new char[mMetadata.GridWidth, mMetadata.GridHeight];
 161
 162                 int y;
 163                 for (y = 0; y < mMetadata.GridHeight && !mInput.End; y++)
 164                 {
 165                     string line = mInput.ReadLine();
 166
 167                     if (line.Length < mMetadata.GridWidth)
 168                     {
 169                         throw new Exception("Unexpected EOL on line " + mInput.LineNumber +
 170                             ": The number of characters should match the width dimension (" + mMetadata.GridWidth + ").");
 171                     }
 172
 173                     for (int x = 0; x < mMetadata.GridWidth; x++)
 174                     {
 175                         mGrid[x, y] = line[x];
 176                     }
 177                 }
 178
 179                 if (y < mMetadata.GridHeight)
 180                 {
 181                     throw new Exception("Unexpected EOF on line " + mInput.LineNumber +
 182                         ": The number of lines in this section should match the height dimension (" + mMetadata.GridHeight + ").");
 183                 }
 184
 185                 return null;
 186             }
 187
 188             string ReadEntitySection(char identifier)
 189             {
 190                 Dictionary<string, string> pairs = new Dictionary<string, string>();
 191                 mEntitySections[identifier] = pairs;
 192
 193                 while (!mInput.End)
 194                 {
 195                     string line = mInput.ReadLine();
 196
 197                     string[] pair = Parse.KeyValuePair(line);
 198                     if (pair != null)
 199                     {
 200                         pairs[pair[0]] = pair[1];
 201                     }
 202                     else
 203                     {
 204                         return line;
 205                     }
 206                 }
 207
 208                 return null;
 209             }
 210
 211
 212             void PostProcess()
 213             {
 214                 if (mMetadata == null || mGrid == null)
 215                 {
 216                     throw new Exception("Missing a required section.  Make sure the metadata and grid are there.");
 217                 }
 218
 219                 mEntities = new List<Map.RawEntity>();
 220                 mPlayerPositions = new Point[mMetadata.NumPlayers.Max() + 1];
 221
 222                 // create entities defined completely
 223                 foreach (char identifier in mEntitySections.Keys)
 224                 {
 225                     Dictionary<string, string> pairs = mEntitySections[identifier];
 226                     if (pairs.ContainsKey("create"))
 227                     {
 228                         string[] list = Parse.List(pairs["create"]);
 229                         foreach (string positionString in list)
 230                         {
 231                             Point? position = Parse.Coordinates(positionString);
 232                             if (position != null)
 233                             {
 234                                 Map.RawEntity createEntity = new Map.RawEntity();
 235                                 createEntity.Id = identifier;
 236                                 createEntity.Position = position.Value;
 237                                 createEntity.Attributes = pairs;
 238                                 mEntities.Add(createEntity);
 239                             }
 240                             else
 241                             {
 242                                 throw new Exception("Unexpected value of key `create' defined for entity " + identifier + ".");
 243                             }
 244                         }
 245                         pairs.Remove("create");
 246                     }
 247                 }
 248
 249                 // create entities with positions defined on the grid
 250                 // and get player starting positions
 251                 for (int x = 0; x < mMetadata.GridWidth; x++)
 252                 {
 253                     for (int y = 0; y < mMetadata.GridHeight; y++)
 254                     {
 255                         char identifier = mGrid[x, y];
 256                         if (IsValidEntityIdentifier(identifier))
 257                         {
 258                             if (mEntitySections.ContainsKey(identifier))
 259                             {
 260                                 Map.RawEntity createEntity = new Map.RawEntity();
 261                                 createEntity.Id = identifier;
 262                                 createEntity.Position = new Point(x, y);
 263                                 createEntity.Attributes = mEntitySections[identifier];
 264                                 mEntities.Add(createEntity);
 265                             }
 266                             else
 267                             {
 268                                 throw new Exception("Unexpected entity (" + identifier +
 269                                     ") placed on the grid at [" + x + "," + y + "] but not defined.");
 270                             }
 271                             mGrid[x, y] = mDefaultTile;
 272                         }
 273                         else if ('1' <= identifier && identifier <= '9')
 274                         {
 275                             int playerNum = identifier - 48;
 276                             if (playerNum < mPlayerPositions.Count())
 277                             {
 278                                 mPlayerPositions[playerNum] = new Point(x, y);
 279                             }
 280                             mGrid[x, y] = mDefaultTile;
 281                         }
 282                     }
 283                 }
 284
 285                 // check if all needed player positions are defined
 286                 for (int i = 1; i < mPlayerPositions.Count(); i++)
 287                 {
 288                     if (mPlayerPositions[i] == default(Point))
 289                     {
 290                         throw new Exception("Not enough player positions were defined on the grid; " +
 291                             "you are missing a spot for player " + i + ".");
 292                     }
 293                 }
 294             }
 295
 296
 297             bool IsLineSignificant(string line)
 298             {
 299                 if (line.Trim().Length == 0 || Parse.IniComment(line) != null) return false;
 300                 return true;
 301             }
 302
 303             bool IsValidEntityIdentifier(char id)
 304             {
 305                 if (('a' <= id && id <= 'z') || ('A' <= id && id <= 'Z')) return true;
 306                 return false;
 307             }
 308
 309
 310             public void set_author(string atom)
 311             {
 312                 string value = Parse.String(atom);
 313                 if (value != null) mMetadata.Author = value;
 314                 else throw new Exception("Unexpected value on line " + mInput.LineNumber + ": " + atom);
 315             }
 316
 317             public void set_levelname(string atom)
 318             {
 319                 string value = Parse.String(atom);
 320                 if (value != null) mMetadata.Name = value;
 321                 else throw new Exception("Unexpected value on line " + mInput.LineNumber + ": " + atom);
 322             }
 323
 324             public void set_next(string atom)
 325             {
 326                 string value = Parse.String(atom);
 327                 if (value != null) mMetadata.Next = value;
 328                 else throw new Exception("Unexpected value on line " + mInput.LineNumber + ": " + atom);
 329             }
 330
 331             public void set_type(string atom)
 332             {
 333                 Map.Mode? value = Parse.Constant<Map.Mode>(atom);
 334                 if (value != null) mMetadata.Type = value.Value;
 335                 else throw new Exception("Unexpected type on line " + mInput.LineNumber + ": " + atom);
 336             }
 337
 338             public void set_dimensions(string atom)
 339             {
 340                 Point? dimensions = Parse.Coordinates(atom);
 341                 if (dimensions != null)
 342                 {
 343                     mMetadata.GridWidth = dimensions.Value.X;
 344                     mMetadata.GridHeight = dimensions.Value.Y;
 345                     if (mMetadata.GridWidth <= 0 || mMetadata.GridHeight <= 0)
 346                     {
 347                         throw new Exception("Invalid dimensions on line " + mInput.LineNumber + ": " + atom);
 348                     }
 349                 }
 350                 else
 351                 {
 352                     throw new Exception("Unexpected value on line " + mInput.LineNumber + ": " + atom);
 353                 }
 354             }
 355
 356             public void set_tileset(string atom)
 357             {
 358                 string value = Parse.String(atom);
 359                 if (value != null) mMetadata.Tileset = value;
 360                 else throw new Exception("Unexpected tileset on line " + mInput.LineNumber + ": " + atom);
 361             }
 362
 363             public void set_defaulttile(string atom)
 364             {
 365                 char? value = Parse.Char(atom);
 366                 if (value != null) mDefaultTile = value.Value;
 367                 else throw new Exception("Unexpected tile value on line " + mInput.LineNumber + ": " + atom);
 368             }
 369
 370             public void set_numplayers(string atom)
 371             {
 372                 string[] list = Parse.List(atom);
 373                 if (list != null)
 374                 {
 375                     foreach (string item in list)
 376                     {
 377                         int[] range = Parse.Range(item);
 378                         if (range != null)
 379                         {
 380                             for (int i = range[0]; i <= range[1]; i++)
 381                             {
 382                                 mMetadata.NumPlayers.Add(i);
 383                             }
 384                             continue;
 385                         }
 386                         int? integer = Parse.Integer(item);
 387                         if (integer != null)
 388                         {
 389                             mMetadata.NumPlayers.Add(integer.Value);
 390                             continue;
 391                         }
 392
 393                         throw new Exception("Unexpected atom on line " + mInput.LineNumber + ": " + item);
 394                     }
 395                     if (mMetadata.NumPlayers.Count == 0)
 396                     {
 397                         throw new Exception("No numbers given on line " + mInput.LineNumber + ": " + atom);
 398                     }
 399                 }
 400                 else
 401                 {
 402                     throw new Exception("Unexpected value on line " + mInput.LineNumber + ": " + atom);
 403                 }
 404             }
 405
 406
 407             Map.Metadata mMetadata;
 408             char[,] mGrid;
 409             List<Map.RawEntity> mEntities;
 410             Point[] mPlayerPositions;
 411             char mDefaultTile = ' ';
 412
 413             Dictionary<char, Dictionary<string, string>> mEntitySections = new Dictionary<char, Dictionary<string, string>>();
 414             LineReader mInput;
 415         }
 416
 417         #endregion
 418
 419
 420         #region Private Variables
 421
 422         Impl mImpl;
 423
 424         #endregion
 425     }
 426 }