001package net.minecraftforge.common;
002
003import java.lang.reflect.*;
004import java.util.*;
005
006import net.minecraft.block.EnumMobType;
007import net.minecraft.block.material.Material;
008import net.minecraft.enchantment.EnumEnchantmentType;
009import net.minecraft.entity.EnumCreatureAttribute;
010import net.minecraft.entity.EnumCreatureType;
011import net.minecraft.entity.EnumEntitySize;
012import net.minecraft.entity.player.EnumStatus;
013import net.minecraft.item.EnumAction;
014import net.minecraft.item.EnumArmorMaterial;
015import net.minecraft.item.EnumToolMaterial;
016import net.minecraft.util.EnumArt;
017import net.minecraft.util.EnumMovingObjectType;
018import net.minecraft.world.EnumSkyBlock;
019import net.minecraft.world.gen.structure.EnumDoor;
020
021public class EnumHelper
022{
023    private static Object reflectionFactory      = null;
024    private static Method newConstructorAccessor = null;
025    private static Method newInstance            = null;
026    private static Method newFieldAccessor       = null;
027    private static Method fieldAccessorSet       = null;
028    private static boolean isSetup               = false;
029
030    //Some enums are decompiled with extra arguments, so lets check for that
031    private static Class[][] commonTypes =
032    {
033        {EnumAction.class},
034        {EnumArmorMaterial.class, int.class, int[].class, int.class},
035        {EnumArt.class, String.class, int.class, int.class, int.class, int.class},
036        {EnumCreatureAttribute.class},
037        {EnumCreatureType.class, Class.class, int.class, Material.class, boolean.class},
038        {EnumDoor.class},
039        {EnumEnchantmentType.class},
040        {EnumEntitySize.class},
041        {EnumMobType.class},
042        {EnumMovingObjectType.class},
043        {EnumSkyBlock.class, int.class},
044        {EnumStatus.class},
045        {EnumToolMaterial.class, int.class, int.class, float.class, int.class, int.class}
046    }; 
047
048    public static EnumAction addAction(String name)
049    {
050        return addEnum(EnumAction.class, name);
051    }
052    public static EnumArmorMaterial addArmorMaterial(String name, int durability, int[] reductionAmounts, int enchantability)
053    {
054        return addEnum(EnumArmorMaterial.class, name, durability, reductionAmounts, enchantability);
055    }
056    public static EnumArt addArt(String name, String tile, int sizeX, int sizeY, int offsetX, int offsetY)
057    {
058        return addEnum(EnumArt.class, name, tile, sizeX, sizeY, offsetX, offsetY);
059    }
060    public static EnumCreatureAttribute addCreatureAttribute(String name)
061    {
062        return addEnum(EnumCreatureAttribute.class, name);
063    }
064    public static EnumCreatureType addCreatureType(String name, Class typeClass, int maxNumber, Material material, boolean peaceful)
065    {
066        return addEnum(EnumCreatureType.class, name, typeClass, maxNumber, material, peaceful);
067    }
068    public static EnumDoor addDoor(String name)
069    {
070        return addEnum(EnumDoor.class, name);
071    }
072    public static EnumEnchantmentType addEnchantmentType(String name)
073    {
074        return addEnum(EnumEnchantmentType.class, name);
075    }
076    public static EnumEntitySize addEntitySize(String name)
077    {
078        return addEnum(EnumEntitySize.class, name);
079    }
080    public static EnumMobType addMobType(String name)
081    {
082        return addEnum(EnumMobType.class, name);
083    }
084    public static EnumMovingObjectType addMovingObjectType(String name)
085    {
086        if (!isSetup)
087        {
088            setup();
089        }
090
091        return addEnum(EnumMovingObjectType.class, name);
092    }
093    public static EnumSkyBlock addSkyBlock(String name, int lightValue)
094    {
095        return addEnum(EnumSkyBlock.class, name, lightValue);
096    }
097    public static EnumStatus addStatus(String name)
098    {
099        return addEnum(EnumStatus.class, name);
100    }
101    public static EnumToolMaterial addToolMaterial(String name, int harvestLevel, int maxUses, float efficiency, int damage, int enchantability)
102    {
103        return addEnum(EnumToolMaterial.class, name, harvestLevel, maxUses, efficiency, damage, enchantability);
104    }
105
106    private static void setup()
107    {
108        if (isSetup)
109        {
110            return;
111        }
112
113        try
114        {
115            Method getReflectionFactory = Class.forName("sun.reflect.ReflectionFactory").getDeclaredMethod("getReflectionFactory");
116            reflectionFactory      = getReflectionFactory.invoke(null);
117            newConstructorAccessor = Class.forName("sun.reflect.ReflectionFactory").getDeclaredMethod("newConstructorAccessor", Constructor.class);
118            newInstance            = Class.forName("sun.reflect.ConstructorAccessor").getDeclaredMethod("newInstance", Object[].class);
119            newFieldAccessor       = Class.forName("sun.reflect.ReflectionFactory").getDeclaredMethod("newFieldAccessor", Field.class, boolean.class);
120            fieldAccessorSet       = Class.forName("sun.reflect.FieldAccessor").getDeclaredMethod("set", Object.class, Object.class);
121        }
122        catch (Exception e)
123        {
124            e.printStackTrace();
125        }
126
127        isSetup = true;
128    }
129
130    /*
131     * Everything below this is found at the site below, and updated to be able to compile in Eclipse/Java 1.6+
132     * Also modified for use in decompiled code.
133     * Found at: http://niceideas.ch/roller2/badtrash/entry/java_create_enum_instances_dynamically
134     */
135    private static Object getConstructorAccessor(Class<?> enumClass, Class<?>[] additionalParameterTypes) throws Exception
136    {
137        Class<?>[] parameterTypes = new Class[additionalParameterTypes.length + 2];
138        parameterTypes[0] = String.class;
139        parameterTypes[1] = int.class;
140        System.arraycopy(additionalParameterTypes, 0, parameterTypes, 2, additionalParameterTypes.length);
141        return newConstructorAccessor.invoke(reflectionFactory, enumClass.getDeclaredConstructor(parameterTypes));
142    }
143
144    private static < T extends Enum<? >> T makeEnum(Class<T> enumClass, String value, int ordinal, Class<?>[] additionalTypes, Object[] additionalValues) throws Exception
145    {
146        Object[] parms = new Object[additionalValues.length + 2];
147        parms[0] = value;
148        parms[1] = Integer.valueOf(ordinal);
149        System.arraycopy(additionalValues, 0, parms, 2, additionalValues.length);
150        return enumClass.cast(newInstance.invoke(getConstructorAccessor(enumClass, additionalTypes), new Object[] {parms}));
151    }
152
153    public static void setFailsafeFieldValue(Field field, Object target, Object value) throws Exception
154    {
155        field.setAccessible(true);
156        Field modifiersField = Field.class.getDeclaredField("modifiers");
157        modifiersField.setAccessible(true);
158        modifiersField.setInt(field, field.getModifiers() & ~Modifier.FINAL);
159        Object fieldAccessor = newFieldAccessor.invoke(reflectionFactory, field, false);
160        fieldAccessorSet.invoke(fieldAccessor, target, value);
161    }
162
163    private static void blankField(Class<?> enumClass, String fieldName) throws Exception
164    {
165        for (Field field : Class.class.getDeclaredFields())
166        {
167            if (field.getName().contains(fieldName))
168            {
169                field.setAccessible(true);
170                setFailsafeFieldValue(field, enumClass, null);
171                break;
172            }
173        }
174    }
175
176    private static void cleanEnumCache(Class<?> enumClass) throws Exception
177    {
178        blankField(enumClass, "enumConstantDirectory");
179        blankField(enumClass, "enumConstants");
180    }
181
182    public static <T extends Enum<? >> T addEnum(Class<T> enumType, String enumName, Object... paramValues)
183    {
184        return addEnum(commonTypes, enumType, enumName, paramValues);
185    }
186    
187    public static <T extends Enum<? >> T addEnum(Class[][] map, Class<T> enumType, String enumName, Object... paramValues)
188    {
189        for (Class[] lookup : map)
190        {
191            if (lookup[0] == enumType)
192            {
193                Class<?>[] paramTypes = new Class<?>[lookup.length - 1];
194                if (paramTypes.length > 0)
195                {
196                    System.arraycopy(lookup, 1, paramTypes, 0, paramTypes.length);
197                }
198                return addEnum(enumType, enumName, paramTypes, paramValues);
199            }
200        }
201        return null;
202    }
203
204    @SuppressWarnings("unchecked")
205    public static <T extends Enum<? >> T addEnum(Class<T> enumType, String enumName, Class<?>[] paramTypes, Object[] paramValues)
206    {
207        if (!isSetup)
208        {
209            setup();
210        }
211
212        Field valuesField = null;
213        Field[] fields = enumType.getDeclaredFields();
214        int flags = Modifier.PRIVATE | Modifier.STATIC | Modifier.FINAL | 0x1000 /*SYNTHETIC*/;
215        String valueType = String.format("[L%s;", enumType.getName().replace('.', '/'));
216
217        for (Field field : fields)
218        {
219            if ((field.getModifiers() & flags) == flags &&
220                    field.getType().getName().replace('.', '/').equals(valueType)) //Apparently some JVMs return .'s and some don't..
221            {
222                valuesField = field;
223                break;
224            }
225        }
226        valuesField.setAccessible(true);
227
228        try
229        {
230            T[] previousValues = (T[])valuesField.get(enumType);
231            List<T> values = new ArrayList<T>(Arrays.asList(previousValues));
232            T newValue = (T)makeEnum(enumType, enumName, values.size(), paramTypes, paramValues);
233            values.add(newValue);
234            setFailsafeFieldValue(valuesField, null, values.toArray((T[]) Array.newInstance(enumType, 0)));
235            cleanEnumCache(enumType);
236
237            return newValue;
238        }
239        catch (Exception e)
240        {
241            e.printStackTrace();
242            throw new RuntimeException(e.getMessage(), e);
243        }
244    }
245
246    static
247    {
248        if (!isSetup)
249        {
250            setup();
251        }
252    }
253}