Wizardry/src/main/java/electroblob/wizardry/spell/Blink.java

package electroblob.wizardry.spell;

import electroblob.wizardry.Wizardry;
import electroblob.wizardry.registry.WizardryItems;
import electroblob.wizardry.util.RayTracer;
import electroblob.wizardry.util.SpellModifiers;
import electroblob.wizardry.util.WizardryUtilities;
import net.minecraft.entity.EntityLiving;
import net.minecraft.entity.EntityLivingBase;
import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.item.EnumAction;
import net.minecraft.util.EnumFacing;
import net.minecraft.util.EnumHand;
import net.minecraft.util.EnumParticleTypes;
import net.minecraft.util.math.BlockPos;
import net.minecraft.util.math.MathHelper;
import net.minecraft.util.math.RayTraceResult;
import net.minecraft.world.World;

public class Blink extends Spell {

	public Blink(){
		super("blink", EnumAction.NONE, false);
		addProperties(RANGE);
	}

	@Override
	public boolean cast(World world, EntityPlayer caster, EnumHand hand, int ticksInUse, SpellModifiers modifiers){

		RayTraceResult rayTrace = RayTracer.standardBlockRayTrace(world, caster,
				getProperty(RANGE).doubleValue() * modifiers.get(WizardryItems.range_upgrade), false);

		// It's worth noting that on the client side, the cast() method only gets called if the server side
		// cast method succeeded, so you need not check any conditions for spawning particles.
		if(world.isRemote){
			for(int i = 0; i < 10; i++){
				double dx = caster.posX;
				double dy = caster.getEntityBoundingBox().minY + 2 * world.rand.nextFloat();
				double dz = caster.posZ;
				// For portal particles, velocity is not velocity but the offset where they start, then drift to
				// the actual position given.
				world.spawnParticle(EnumParticleTypes.PORTAL, dx, dy, dz, world.rand.nextDouble() - 0.5,
						world.rand.nextDouble() - 0.5, world.rand.nextDouble() - 0.5);
			}

			Wizardry.proxy.playBlinkEffect(caster);
		}

		if(rayTrace != null && rayTrace.typeOfHit == RayTraceResult.Type.BLOCK){

			BlockPos pos = rayTrace.getBlockPos();

			// Leave space for the player's head
			if(rayTrace.sideHit == EnumFacing.DOWN) pos = pos.down();

			// This means stuff like snow layers is ignored, meaning when on snow-covered ground the player does
			// not teleport 1 block above the ground.
			if(rayTrace.sideHit == EnumFacing.UP && !world.getBlockState(pos).getMaterial().blocksMovement()){
				pos = pos.down();
			}

			pos = pos.offset(rayTrace.sideHit);

			// Prevents the player from teleporting into blocks and suffocating.
			if(world.getBlockState(pos).getMaterial().blocksMovement()
					|| world.getBlockState(pos.up()).getMaterial().blocksMovement()){
				return false;
			}

			// Plays before and after so it is heard from both positions
			this.playSound(world, caster, ticksInUse, -1, modifiers);

			if(!world.isRemote) caster.setPositionAndUpdate(pos.getX() + 0.5, pos.getY(), pos.getZ() + 0.5);

			this.playSound(world, caster, ticksInUse, -1, modifiers);
			caster.swingArm(hand);
			return true;
		}

		return false;
	}

	@Override
	public boolean cast(World world, EntityLiving caster, EnumHand hand, int ticksInUse, EntityLivingBase target,
			SpellModifiers modifiers){

		float angle = (float)(Math.atan2(target.posZ - caster.posZ, target.posX - caster.posX)
				+ world.rand.nextDouble() * Math.PI);
		double radius = caster.getDistance(target.posX, target.getEntityBoundingBox().minY, target.posZ)
				+ world.rand.nextDouble() * 3.0d;

		int x = MathHelper.floor(target.posX + MathHelper.sin(angle) * radius);
		int z = MathHelper.floor(target.posZ - MathHelper.cos(angle) * radius);
		Integer y = WizardryUtilities.getNearestFloor(world, new BlockPos(caster), (int)radius);

		// It's worth noting that on the client side, the cast() method only gets called if the server side
		// cast method succeeded, so you need not check any conditions for spawning particles.

		// For some reason, the wizard version spwans the particles where the wizard started
		if(world.isRemote){
			for(int i = 0; i < 10; i++){
				double dx1 = caster.posX;
				double dy1 = caster.getEntityBoundingBox().minY + caster.height * world.rand.nextFloat();
				double dz1 = caster.posZ;
				world.spawnParticle(EnumParticleTypes.PORTAL, dx1, dy1, dz1, world.rand.nextDouble() - 0.5,
						world.rand.nextDouble() - 0.5, world.rand.nextDouble() - 0.5);
			}
		}

		if(y != null){

			// This means stuff like snow layers is ignored, meaning when on snow-covered ground the caster does
			// not teleport 1 block above the ground.
			if(!world.getBlockState(new BlockPos(x, y, z)).getMaterial().blocksMovement()){
				y--;
			}

			if(world.getBlockState(new BlockPos(x, y + 1, z)).getMaterial().blocksMovement()
					|| world.getBlockState(new BlockPos(x, y + 2, z)).getMaterial().blocksMovement()){
				return false;
			}

			// Plays before and after so it is heard from both positions
			this.playSound(world, caster, ticksInUse, -1, modifiers);

			if(!world.isRemote){
				caster.setPositionAndUpdate(x + 0.5, y + 1, z + 0.5);
			}

			this.playSound(world, caster, ticksInUse, -1, modifiers);
			caster.swingArm(hand);
			return true;
		}

		return false;
	}

	@Override
	public boolean canBeCastByNPCs(){
		return true;
	}

}