Code/net/minecraft/world/entity/ai/behavior/AnimalMakeLove.java

package net.minecraft.world.entity.ai.behavior;

import com.google.common.collect.ImmutableMap;
import java.util.Optional;
import net.minecraft.server.level.ServerLevel;
import net.minecraft.world.entity.EntityType;
import net.minecraft.world.entity.LivingEntity;
import net.minecraft.world.entity.ai.Brain;
import net.minecraft.world.entity.ai.memory.MemoryModuleType;
import net.minecraft.world.entity.ai.memory.MemoryStatus;
import net.minecraft.world.entity.animal.Animal;

public class AnimalMakeLove extends Behavior<Animal> {
    private static final int BREED_RANGE = 3;
    private static final int MIN_DURATION = 60;
    private static final int MAX_DURATION = 110;
    private final EntityType<? extends Animal> partnerType;
    private final float speedModifier;
    private final int closeEnoughDistance;
    private static final int DEFAULT_CLOSE_ENOUGH_DISTANCE = 2;
    private long spawnChildAtTime;

    public AnimalMakeLove(EntityType<? extends Animal> p_22391_) {
        this(p_22391_, 1.0F, 2);
    }

    public AnimalMakeLove(EntityType<? extends Animal> p_329113_, float p_335591_, int p_332468_) {
        super(
            ImmutableMap.of(
                MemoryModuleType.NEAREST_VISIBLE_LIVING_ENTITIES,
                MemoryStatus.VALUE_PRESENT,
                MemoryModuleType.BREED_TARGET,
                MemoryStatus.VALUE_ABSENT,
                MemoryModuleType.WALK_TARGET,
                MemoryStatus.REGISTERED,
                MemoryModuleType.LOOK_TARGET,
                MemoryStatus.REGISTERED,
                MemoryModuleType.IS_PANICKING,
                MemoryStatus.VALUE_ABSENT
            ),
            110
        );
        this.partnerType = p_329113_;
        this.speedModifier = p_335591_;
        this.closeEnoughDistance = p_332468_;
    }

    protected boolean checkExtraStartConditions(ServerLevel p_22401_, Animal p_22402_) {
        return p_22402_.isInLove() && this.findValidBreedPartner(p_22402_).isPresent();
    }

    protected void start(ServerLevel p_22404_, Animal p_22405_, long p_22406_) {
        Animal animal = this.findValidBreedPartner(p_22405_).get();
        p_22405_.getBrain().setMemory(MemoryModuleType.BREED_TARGET, animal);
        animal.getBrain().setMemory(MemoryModuleType.BREED_TARGET, p_22405_);
        BehaviorUtils.lockGazeAndWalkToEachOther(p_22405_, animal, this.speedModifier, this.closeEnoughDistance);
        int i = 60 + p_22405_.getRandom().nextInt(50);
        this.spawnChildAtTime = p_22406_ + i;
    }

    protected boolean canStillUse(ServerLevel p_22416_, Animal p_22417_, long p_22418_) {
        if (!this.hasBreedTargetOfRightType(p_22417_)) {
            return false;
        } else {
            Animal animal = this.getBreedTarget(p_22417_);
            return animal.isAlive()
                && p_22417_.canMate(animal)
                && BehaviorUtils.entityIsVisible(p_22417_.getBrain(), animal)
                && p_22418_ <= this.spawnChildAtTime
                && !p_22417_.isPanicking()
                && !animal.isPanicking();
        }
    }

    protected void tick(ServerLevel p_22428_, Animal p_22429_, long p_22430_) {
        Animal animal = this.getBreedTarget(p_22429_);
        BehaviorUtils.lockGazeAndWalkToEachOther(p_22429_, animal, this.speedModifier, this.closeEnoughDistance);
        if (p_22429_.closerThan(animal, 3.0)) {
            if (p_22430_ >= this.spawnChildAtTime) {
                p_22429_.spawnChildFromBreeding(p_22428_, animal);
                p_22429_.getBrain().eraseMemory(MemoryModuleType.BREED_TARGET);
                animal.getBrain().eraseMemory(MemoryModuleType.BREED_TARGET);
            }
        }
    }

    protected void stop(ServerLevel p_22438_, Animal p_22439_, long p_22440_) {
        p_22439_.getBrain().eraseMemory(MemoryModuleType.BREED_TARGET);
        p_22439_.getBrain().eraseMemory(MemoryModuleType.WALK_TARGET);
        p_22439_.getBrain().eraseMemory(MemoryModuleType.LOOK_TARGET);
        this.spawnChildAtTime = 0L;
    }

    private Animal getBreedTarget(Animal p_22410_) {
        return (Animal)p_22410_.getBrain().getMemory(MemoryModuleType.BREED_TARGET).get();
    }

    private boolean hasBreedTargetOfRightType(Animal p_22422_) {
        Brain<?> brain = p_22422_.getBrain();
        return brain.hasMemoryValue(MemoryModuleType.BREED_TARGET) && brain.getMemory(MemoryModuleType.BREED_TARGET).get().getType() == this.partnerType;
    }

    private Optional<? extends Animal> findValidBreedPartner(Animal p_22432_) {
        return p_22432_.getBrain()
            .getMemory(MemoryModuleType.NEAREST_VISIBLE_LIVING_ENTITIES)
            .get()
            .findClosest(
                p_390544_ -> p_390544_.getType() == this.partnerType && p_390544_ instanceof Animal animal && p_22432_.canMate(animal) && !animal.isPanicking()
            )
            .map(Animal.class::cast);
    }
}