Fluid API Sketch: FluidVolume

FluidVolume.java

/*
 * Copyright (c) 2016, 2017, 2018, 2019 FabricMC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package net.fabricmc.fabric.api.fluid.v1.fluid;

/**
 * The fluid analog of ItemStack
 */
public interface FluidVolume extends ImmutableFluidVolume {
    
    /**
     * TODO: should this be mutable or fixed at instantiation?
     */
    void setMaxBuckets(long buckets);
    
    /**
     * Sets volume exactly.  Must be less than {@link #getMaxBuckets()} or
     * an exception will be thrown.
     */
    void setVolume(long volume, long units);
    
    /**
     * Removes up to the given number of units and returns that number.
     */
    long drain(long volume, long units, boolean simiulate);
    
    default long drain(long volume, long units) {
        return drain(volume, units, false);
    }
    
    /**
     * True if the given number of units is removed. 
     * Otherwise no effect and returns false. 
     */
    boolean drainExactly(long volume, long units, boolean simiulate);
    
    default boolean drainExactly(long volume, long units) {
        return drainExactly(volume, units);
    }
    
    /**
     * Adds up to the given number of units and returns that number.
     */
    long fill(long volume, long units, boolean simiulate);
    
    default long fill(long volume, long units) {
        return fill(volume, units, false);
    }
    
    /**
     * True if the given number of units is added. 
     * Otherwise no effect and returns false. 
     */
    boolean fillExactly(long volume, long units, boolean simiulate);
    
    default boolean fillExactly(long volume, long units) {
        return fillExactly(volume, units);
    }
    
    FluidVolume copy();
}

ImmutableFluidVolume.java

/*
 * Copyright (c) 2016, 2017, 2018, 2019 FabricMC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package net.fabricmc.fabric.api.fluid.v1.fluid;

import net.minecraft.fluid.Fluid;

public interface ImmutableFluidVolume {
    // Common unit denominators
    int BUCKET = 1;
    int KILOLITER = 1;
    int LITER = 1000;
    int BLOCK = 1;
    int SLAB = 2;
    int BOTTLE = 3;
    int QUARTER = 4;
    int INGOT = 9;
    int NUGGET = 81;
    
    Fluid fluid();
    
    /** 
     * Returns current amount in stack scaled so that that 1.0 = one of the given units.
     * May be approximate due to floating point error.  Intended primarily for user display.
     */
    double volumeForDisplay(long units);
    
    /**
     * Returns the number of units that is less than or equal to contents.
     * Make contain more than this if contents are not evenly divisible . 
     */
    long getVolume(long units);
    
    /** 
     * True if tank is absolutely empty.
     */
    boolean isEmpty();
    
    /** 
     * True if filled volume is less than the given unit.
     */
    boolean isEmpty(long units);
    
    /**
     * Max fill volume measured in BUCKETS.  
     * (Max can't be a fractional unit. That way lies madness.)
     */
    long getMaxBuckets();
    
    /**
     * Returns self if already immutable.
     */
    ImmutableFluidVolume toImmutable();
}