content: package net.minecraft.world.gen.feature;
  
  import net.minecraft.block.*;
  import net.minecraft.block.material.Material;
  import net.minecraft.block.properties.PropertyBool;
  import net.minecraft.block.state.IBlockState;
  import net.minecraft.init.Blocks;
  import net.minecraft.util.BlockPos;
  import net.minecraft.world.World;
  
  import java.util.Random;
  
  public class WorldGenSwamp extends WorldGenAbstractTree {
      private static final IBlockState field_181648_a = Blocks.log.getDefaultState().withProperty(BlockOldLog.VARIANT, BlockPlanks.EnumType.OAK);
      private static final IBlockState field_181649_b = Blocks.leaves.getDefaultState().withProperty(BlockOldLeaf.VARIANT, BlockPlanks.EnumType.OAK).withProperty(BlockOldLeaf.CHECK_DECAY, false);
  
      public WorldGenSwamp() {
          super(false);
      }
  
      public boolean generate(World worldIn, Random rand, BlockPos position) {
          int i;
  
          for (i = rand.nextInt(4) + 5; worldIn.getBlockState(position.down()).getBlock().getMaterial() == Material.water; position = position.down()) {
          }
  
          boolean flag = true;
  
          if (position.getY() >= 1 && position.getY() + i + 1 <= 256) {
              for (int j = position.getY(); j <= position.getY() + 1 + i; ++j) {
                  int k = 1;
  
                  if (j == position.getY()) {
                      k = 0;
                  }
  
                  if (j >= position.getY() + 1 + i - 2) {
                      k = 3;
                  }
  
                  BlockPos.MutableBlockPos blockpos$mutableblockpos = new BlockPos.MutableBlockPos();
  
                  for (int l = position.getX() - k; l <= position.getX() + k && flag; ++l) {
                      for (int i1 = position.getZ() - k; i1 <= position.getZ() + k && flag; ++i1) {
                          if (j >= 0 && j < 256) {
                              Block block = worldIn.getBlockState(blockpos$mutableblockpos.set(l, j, i1)).getBlock();
  
                              if (block.getMaterial() != Material.air && block.getMaterial() != Material.leaves) {
                                  if (block != Blocks.water && block != Blocks.flowing_water) {
                                      flag = false;
                                  } else if (j > position.getY()) {
                                      flag = false;
                                  }
                              }
                          } else {
                              flag = false;
                          }
                      }
                  }
              }
  
              if (!flag) {
                  return false;
              } else {
                  Block block1 = worldIn.getBlockState(position.down()).getBlock();
  
                  if ((block1 == Blocks.grass || block1 == Blocks.dirt) && position.getY() < 256 - i - 1) {
                      this.func_175921_a(worldIn, position.down());
  
                      for (int l1 = position.getY() - 3 + i; l1 <= position.getY() + i; ++l1) {
                          int k2 = l1 - (position.getY() + i);
                          int i3 = 2 - k2 / 2;
  
                          for (int k3 = position.getX() - i3; k3 <= position.getX() + i3; ++k3) {
                              int l3 = k3 - position.getX();
  
                              for (int j1 = position.getZ() - i3; j1 <= position.getZ() + i3; ++j1) {
                                  int k1 = j1 - position.getZ();
  
                                  if (Math.abs(l3) != i3 || Math.abs(k1) != i3 || rand.nextInt(2) != 0 && k2 != 0) {
                                      BlockPos blockpos = new BlockPos(k3, l1, j1);
  
                                      if (!worldIn.getBlockState(blockpos).getBlock().isFullBlock()) {
                                          this.setBlockAndNotifyAdequately(worldIn, blockpos, field_181649_b);
                                      }
                                  }
                              }
                          }
                      }
  
                      for (int i2 = 0; i2 < i; ++i2) {
                          Block block2 = worldIn.getBlockState(position.up(i2)).getBlock();
  
                          if (block2.getMaterial() == Material.air || block2.getMaterial() == Material.leaves || block2 == Blocks.flowing_water || block2 == Blocks.water) {
                              this.setBlockAndNotifyAdequately(worldIn, position.up(i2), field_181648_a);
                          }
                      }
  
                      for (int j2 = position.getY() - 3 + i; j2 <= position.getY() + i; ++j2) {
                          int l2 = j2 - (position.getY() + i);
                          int j3 = 2 - l2 / 2;
                          BlockPos.MutableBlockPos blockpos$mutableblockpos1 = new BlockPos.MutableBlockPos();
  
                          for (int i4 = position.getX() - j3; i4 <= position.getX() + j3; ++i4) {
                              for (int j4 = position.getZ() - j3; j4 <= position.getZ() + j3; ++j4) {
                                  blockpos$mutableblockpos1.set(i4, j2, j4);
  
                                  if (worldIn.getBlockState(blockpos$mutableblockpos1).getBlock().getMaterial() == Material.leaves) {
                                      BlockPos blockpos3 = blockpos$mutableblockpos1.west();
                                      BlockPos blockpos4 = blockpos$mutableblockpos1.east();
                                      BlockPos blockpos1 = blockpos$mutableblockpos1.north();
                                      BlockPos blockpos2 = blockpos$mutableblockpos1.south();
  
                                      if (rand.nextInt(4) == 0 && worldIn.getBlockState(blockpos3).getBlock().getMaterial() == Material.air) {
                                          this.func_181647_a(worldIn, blockpos3, BlockVine.EAST);
                                      }
  
                                      if (rand.nextInt(4) == 0 && worldIn.getBlockState(blockpos4).getBlock().getMaterial() == Material.air) {
                                          this.func_181647_a(worldIn, blockpos4, BlockVine.WEST);
                                      }
  
                                      if (rand.nextInt(4) == 0 && worldIn.getBlockState(blockpos1).getBlock().getMaterial() == Material.air) {
                                          this.func_181647_a(worldIn, blockpos1, BlockVine.SOUTH);
                                      }
  
                                      if (rand.nextInt(4) == 0 && worldIn.getBlockState(blockpos2).getBlock().getMaterial() == Material.air) {
                                          this.func_181647_a(worldIn, blockpos2, BlockVine.NORTH);
                                      }
                                  }
                              }
                          }
                      }
  
                      return true;
                  } else {
                      return false;
                  }
              }
          } else {
              return false;
          }
      }
  
      private void func_181647_a(World p_181647_1_, BlockPos p_181647_2_, PropertyBool p_181647_3_) {
          IBlockState iblockstate = Blocks.vine.getDefaultState().withProperty(p_181647_3_, true);
          this.setBlockAndNotifyAdequately(p_181647_1_, p_181647_2_, iblockstate);
          int i = 4;
  
          for (p_181647_2_ = p_181647_2_.down(); p_181647_1_.getBlockState(p_181647_2_).getBlock().getMaterial() == Material.air && i > 0; --i) {
              this.setBlockAndNotifyAdequately(p_181647_1_, p_181647_2_, iblockstate);
              p_181647_2_ = p_181647_2_.down();
          }
      }
  }
  