minecraft-kajetans-mod/src/main/java/me/km/blocks/BlockEvents.java

package me.km.blocks;

import com.google.common.collect.Sets;
import java.util.List;
import java.util.Random;
import java.util.Set;
import me.km.utils.ReflectionUtils;
import net.minecraft.block.Block;
import net.minecraft.block.material.Material;
import net.minecraft.block.state.IBlockState;
import net.minecraft.enchantment.EnchantmentProtection;
import net.minecraft.entity.Entity;
import net.minecraft.entity.EntityLivingBase;
import net.minecraft.entity.item.EntityTNTPrimed;
import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.init.Blocks;
import net.minecraft.init.SoundEvents;
import net.minecraft.util.DamageSource;
import net.minecraft.util.EnumParticleTypes;
import net.minecraft.util.SoundCategory;
import net.minecraft.util.math.AxisAlignedBB;
import net.minecraft.util.math.BlockPos;
import net.minecraft.util.math.MathHelper;
import net.minecraft.util.math.Vec3d;
import net.minecraft.world.Explosion;
import net.minecraft.world.World;
import net.minecraftforge.event.world.ExplosionEvent;
import net.minecraftforge.fml.common.eventhandler.EventPriority;
import net.minecraftforge.fml.common.eventhandler.SubscribeEvent;

public class BlockEvents 
{
    @SubscribeEvent(receiveCanceled = false, priority = EventPriority.LOWEST)
    public void onExplosion(ExplosionEvent.Start e)
    {
        Explosion ex = e.getExplosion();
        Entity ent = ReflectionUtils.getExploder(ex);
        if(ReflectionUtils.getSize(ex) > 10)
        {
            ReflectionUtils.setSize(ex, 10);
        }
        e.setCanceled(true);
        doExplosionA(ex, e.getWorld(), ent instanceof EntityTNTPrimed);
        doExplosionB(ex, e.getWorld(), true);
    }
    
    public void doExplosionA(Explosion ex, World w, boolean tnt)
    {
        Set<BlockPos> set = Sets.<BlockPos>newHashSet();
        int i = 16;

        Vec3d v = ex.getPosition();
        float explosionSize = ReflectionUtils.getSize(ex);
        Entity exploder = ReflectionUtils.getExploder(ex);
        for(int j = 0; j < 16; ++j)
        {
            for(int k = 0; k < 16; ++k)
            {
                for(int l = 0; l < 16; ++l)
                {
                    if(j == 0 || j == 15 || k == 0 || k == 15 || l == 0 || l == 15)
                    {
                        double d0 = j / 15f * 2 - 1;
                        double d1 = k / 15f * 2 - 1;
                        double d2 = l / 15f * 2 - 1;
                        double d3 = Math.sqrt(d0 * d0 + d1 * d1 + d2 * d2);
                        d0 = d0 / d3;
                        d1 = d1 / d3;
                        d2 = d2 / d3;
                        float f = explosionSize * (0.7f + w.rand.nextFloat() * 0.6f);
                        double d4 = v.x;
                        double d6 = v.y;
                        double d8 = v.z;

                        for(float f1 = 0.3F; f > 0.0F; f -= 0.22500001F)
                        {
                            BlockPos blockpos = new BlockPos(d4, d6, d8);
                            IBlockState iblockstate = w.getBlockState(blockpos);

                            if (iblockstate.getMaterial() != Material.AIR)
                            {
                                float f2 = exploder != null ? exploder.getExplosionResistance(ex, w, blockpos, iblockstate) : iblockstate.getBlock().getExplosionResistance(w, blockpos, null, ex);
                                // TNT hook
                                if(tnt && f2 <= 10)
                                {
                                    f2 = Math.min(f2, 1);
                                }
                                // end
                                f -= (f2 + 0.3F) * 0.3F;
                            }

                            if (f > 0.0F && (exploder == null || exploder.canExplosionDestroyBlock(ex, w, blockpos, iblockstate, f)))
                            {
                                set.add(blockpos);
                            }

                            d4 += d0 * 0.3d;
                            d6 += d1 * 0.3d;
                            d8 += d2 * 0.3d;
                        }
                    }
                }
            }
        }

        ex.getAffectedBlockPositions().addAll(set);
        float f3 = explosionSize * 2;
        int k1 = MathHelper.floor(v.x - f3 - 1);
        int l1 = MathHelper.floor(v.x + f3 + 1);
        int i2 = MathHelper.floor(v.y - f3 - 1);
        int i1 = MathHelper.floor(v.y + f3 + 1);
        int j2 = MathHelper.floor(v.z - f3 - 1);
        int j1 = MathHelper.floor(v.z + f3 + 1);
        List<Entity> list = w.getEntitiesWithinAABBExcludingEntity(exploder, new AxisAlignedBB(k1, i2, j2, l1, i1, j1));
        net.minecraftforge.event.ForgeEventFactory.onExplosionDetonate(w, ex, list, f3);
        Vec3d vec3d = new Vec3d(v.x, v.y, v.z);

        for(int k2 = 0; k2 < list.size(); k2++)
        {
            Entity entity = list.get(k2);

            if(!entity.isImmuneToExplosions())
            {
                double d12 = entity.getDistance(v.x, v.y, v.z) / f3;

                if(d12 <= 1.0D)
                {
                    double d5 = entity.posX - v.x;
                    double d7 = entity.posY + (double)entity.getEyeHeight() - v.y;
                    double d9 = entity.posZ - v.z;
                    double d13 = MathHelper.sqrt(d5 * d5 + d7 * d7 + d9 * d9);

                    if(d13 != 0.0D)
                    {
                        d5 = d5 / d13;
                        d7 = d7 / d13;
                        d9 = d9 / d13;
                        double d14 = w.getBlockDensity(vec3d, entity.getEntityBoundingBox());
                        double d10 = (1.0D - d12) * d14;
                        entity.attackEntityFrom(DamageSource.causeExplosionDamage(ex), (float)((int)((d10 * d10 + d10) / 2 * 7 * f3 + 1)));
                        double d11 = d10;

                        if(entity instanceof EntityLivingBase)
                        {
                            d11 = EnchantmentProtection.getBlastDamageReduction((EntityLivingBase) entity, d10);
                        }

                        entity.motionX += d5 * d11;
                        entity.motionY += d7 * d11;
                        entity.motionZ += d9 * d11;

                        if (entity instanceof EntityPlayer)
                        {
                            EntityPlayer entityplayer = (EntityPlayer)entity;

                            if (!entityplayer.isSpectator() && (!entityplayer.isCreative() || !entityplayer.capabilities.isFlying))
                            {
                                ex.getPlayerKnockbackMap().put(entityplayer, new Vec3d(d5 * d10, d7 * d10, d9 * d10));
                            }
                        }
                    }
                }
            }
        }
    }
    
    private void doExplosionB(Explosion ex, World w, boolean spawnParticles)
    {
        Vec3d v = ex.getPosition();
        double x = v.x;
        double y = v.y;
        double z = v.z;
        w.playSound(null, x, y, z, SoundEvents.ENTITY_GENERIC_EXPLODE, SoundCategory.BLOCKS, 4, (1 + (w.rand.nextFloat() - w.rand.nextFloat()) * 0.2f) * 0.7f);

        if(ReflectionUtils.getSize(ex) >= 2 && ReflectionUtils.isSmoking(ex))
        {
            w.spawnParticle(EnumParticleTypes.EXPLOSION_HUGE, x, y, z, 1, 0, 0, new int[0]);
        }
        else
        {
            w.spawnParticle(EnumParticleTypes.EXPLOSION_LARGE, x, y, z, 1, 0, 0, new int[0]);
        }

        if(ReflectionUtils.isSmoking(ex))
        {
            float explosionSize = ReflectionUtils.getSize(ex);
            ex.getAffectedBlockPositions().stream().forEach(blockpos -> 
            {
                IBlockState iblockstate = w.getBlockState(blockpos);
                Block block = iblockstate.getBlock();

                if(spawnParticles)
                {
                    double d0 = blockpos.getX() + w.rand.nextFloat();
                    double d1 = blockpos.getY() + w.rand.nextFloat();
                    double d2 = blockpos.getZ() + w.rand.nextFloat();
                    double d3 = d0 - x;
                    double d4 = d1 - y;
                    double d5 = d2 - z;
                    double d6 = MathHelper.sqrt(d3 * d3 + d4 * d4 + d5 * d5);
                    d3 = d3 / d6;
                    d4 = d4 / d6;
                    d5 = d5 / d6;
                    double d7 = 0.5D / (d6 / explosionSize + 0.1D);
                    d7 = d7 * (w.rand.nextFloat() * w.rand.nextFloat() + 0.3F);
                    d3 = d3 * d7;
                    d4 = d4 * d7;
                    d5 = d5 * d7;
                    w.spawnParticle(EnumParticleTypes.EXPLOSION_NORMAL, (d0 + x) / 2, (d1 + y) / 2, (d2 + z) / 2, d3, d4, d5, new int[0]);
                    w.spawnParticle(EnumParticleTypes.SMOKE_NORMAL, d0, d1, d2, d3, d4, d5, new int[0]);
                }

                if(iblockstate.getMaterial() != Material.AIR)
                {
                    if(block.canDropFromExplosion(ex))
                    {
                        block.dropBlockAsItem(w, blockpos, w.getBlockState(blockpos), 0);
                    }
                    block.onBlockExploded(w, blockpos, ex);
                }
            });
        }

        if(ReflectionUtils.isFlaming(ex))
        {
            Random rand = ReflectionUtils.getRandom(ex);
            ex.getAffectedBlockPositions().stream()
                    .filter(pos -> (w.getBlockState(pos).getMaterial() == Material.AIR && 
                                    w.getBlockState(pos.down()).isFullBlock() && 
                                    rand.nextInt(3) == 0))
                    .forEach(pos -> w.setBlockState(pos, Blocks.FIRE.getDefaultState()));
        }
    }
}