Adds domestication syntax (#6861)

* Adds domestication syntax
- An expression with changers
- A test for the expression

* Hopefully fixes tests

* Apply suggestions from code review

Co-authored-by: sovdee <10354869+sovdeeth@users.noreply.github.com>

* Suggestions

* Test suggestions

* Removes reset changer and (hopefully) fixes tests

* Suggestions

* Suggestions

* Adds domestication syntax
- An expression with changers
- A test for the expression

* Hopefully fixes tests

* Apply suggestions from code review

Co-authored-by: sovdee <10354869+sovdeeth@users.noreply.github.com>

* Suggestions

* Test suggestions

* Removes reset changer and (hopefully) fixes tests

* Suggestions

* Suggestions

* Suggestions and some changes

* Suggestion

---------

Co-authored-by: sovdee <10354869+sovdeeth@users.noreply.github.com>
Co-authored-by: Moderocky <admin@moderocky.com>

src/main/java/ch/njol/skript/expressions/ExprDomestication.java

@@ -0,0 +1,103 @@
+package ch.njol.skript.expressions;
+
+import ch.njol.skript.classes.Changer.ChangeMode;
+import ch.njol.skript.doc.Description;
+import ch.njol.skript.doc.Examples;
+import ch.njol.skript.doc.Name;
+import ch.njol.skript.doc.Since;
+import ch.njol.skript.expressions.base.SimplePropertyExpression;
+import ch.njol.skript.lang.Expression;
+import ch.njol.skript.lang.SkriptParser.ParseResult;
+import ch.njol.util.Kleenean;
+import ch.njol.util.Math2;
+import ch.njol.util.coll.CollectionUtils;
+import org.bukkit.entity.AbstractHorse;
+import org.bukkit.entity.LivingEntity;
+import org.bukkit.event.Event;
+import org.jetbrains.annotations.Nullable;
+
+@Name("Horse Domestication")
+@Description({
+	"Gets and/or sets the (max) domestication of a horse.",
+	"The domestication of a horse is how close a horse is to becoming tame - the higher the domestication, the closer they are to becoming tame (must be between 1 and the max domestication level of the horse).",
+	"The max domestication of a horse is how long it will take for a horse to become tame (must be greater than 0)."
+})
+@Examples({
+	"function domesticateAndTame(horse: entity, p: offline player, i: int = 10):",
+		"\tadd {_i} to domestication level of {_horse}",
+		"\tif domestication level of {_horse} >= max domestication level of {_horse}:",
+			"\t\ttame {_horse}",
+			"\t\tset tamer of {_horse} to {_p}"
+})
+@Since("INSERT VERSION")
+public class ExprDomestication extends SimplePropertyExpression<LivingEntity, Integer> {
+
+	static {
+		register(ExprDomestication.class, Integer.class, "[:max[imum]] domestication level", "livingentities");
+	}
+
+	private boolean max;
+
+	@Override
+	public boolean init(Expression<?>[] exprs, int matchedPattern, Kleenean isDelayed, ParseResult parseResult) {
+		max = parseResult.hasTag("max");
+		return super.init(exprs, matchedPattern, isDelayed, parseResult);
+	}
+
+	@Override
+	public @Nullable Integer convert(LivingEntity entity) {
+		if (entity instanceof AbstractHorse horse)
+			return max ? horse.getMaxDomestication() : horse.getDomestication();
+		return null;
+	}
+
+	@Override
+	public @Nullable Class<?>[] acceptChange(ChangeMode mode) {
+		return switch (mode) {
+			case SET, ADD, REMOVE, RESET -> CollectionUtils.array(Number.class);
+			default -> null;
+		};
+	}
+
+	@Override
+	public void change(Event event, Object @Nullable [] delta, ChangeMode mode) {
+		assert mode != ChangeMode.REMOVE_ALL && mode != ChangeMode.DELETE;
+
+		int change = delta == null ? 0 : ((Number) delta[0]).intValue();
+
+		for (LivingEntity entity : getExpr().getArray(event)) {
+			if (entity instanceof AbstractHorse horse) {
+				int level = max ? horse.getMaxDomestication() : horse.getDomestication();
+				switch (mode) {
+					case SET -> level = change;
+					case ADD -> level += change;
+					case REMOVE -> level -= change;
+					case RESET -> level = 1;
+					default -> {
+						assert false;
+						return;
+					}
+				}
+				level = max ? Math.max(level, 1) : Math2.fit(1, level, horse.getMaxDomestication());
+				if (max) {
+					horse.setMaxDomestication(level);
+					if (horse.getDomestication() > level)
+						horse.setDomestication(level);
+				} else {
+					horse.setDomestication(level);
+				}
+			}
+		}
+	}
+
+	@Override
+	public Class<? extends Integer> getReturnType() {
+		return Integer.class;
+	}
+
+	@Override
+	protected String getPropertyName() {
+		return (max ? "max " : "") + "domestication level";
+	}
+
+}

src/test/skript/tests/syntaxes/expressions/ExprDomestication.sk

@@ -0,0 +1,86 @@
+test "domestication":
+	spawn a horse at (spawn of world "world"):
+		set {_e} to entity
+	spawn a zombie at (spawn of world "world"):
+		set {_z} to entity
+
+	# normal values, horse entity
+	set max domestication level of {_e} to 100
+	set domestication level of {_e} to 50
+	assert max domestication level of {_e} is 100 with "setting the max domestication of a horse should do exactly that"
+	assert domestication level of {_e} is 50 with "setting the domestication of a horse should do exactly that"
+
+	add 10 to max domestication level of {_e}
+	add 10 to domestication level of {_e}
+	assert max domestication level of {_e} is 110 with "adding to the max domestication of a horse should do exactly that"
+	assert domestication level of {_e} is 60 with "adding to the domestication of a horse should do exactly that"
+
+	subtract 10 from max domestication level of {_e}
+	subtract 10 from domestication level of {_e}
+	assert max domestication level of {_e} is 100 with "removing from the max domestication of a horse should do exactly that"
+	assert domestication level of {_e} is 50 with "removing from the domestication of a horse should do exactly that"
+
+	subtract 60 from max domestication level of {_e}
+	assert domestication level of {_e} is 40 with "removing from the max domestication level of a horse should also clamp the domestication level if need be"
+
+	reset max domestication level of {_e}
+	reset domestication level of {_e}
+	assert max domestication level of {_e} is 1 with "resetting the max domestication of a horse should do exactly that"
+	assert domestication level of {_e} is 1 with "resetting the domestication of a horse should do exactly that"
+
+	set domestication level of {_e} to (max domestication level of {_e}) + 1
+	add 100 to domestication level of {_e}
+	assert domestication level of {_e} is (max domestication level of {_e}) with "the domestication level of a horse should never exceed it's max domestication level"
+
+	set domestication level of {_e} to 0
+	subtract 100 from domestication level of {_e}
+	assert domestication level of {_e} is 1 with "the domestication level of a horse should never be less than 1"
+
+	set max domestication level of {_e} to 0
+	subtract 100 from max domestication level of {_e}
+	assert max domestication level of {_e} is 1 with "the max domestication level of a horse should never be less than 1"
+
+	# infinity values
+	add infinity value to max domestication level of {_e}
+	assert max domestication level of {_e} is 1 with "infinity value shouldn't affect the max domestication level of a horse when added"
+	subtract infinity value from max domestication level of {_e}
+	assert max domestication level of {_e} is 1 with "infinity value should result in 1 when subtracted from the max domestication level of a horse"
+	set max domestication level of {_e} to infinity value # set is done last so the domestication level tests can also go to infinity
+	assert max domestication level of {_e} is 2147483647 with "infinity value should set the max domestication level of a horse to the max integer value"
+
+	add infinity value to domestication level of {_e}
+	assert domestication level of {_e} is 1 with "infinity value shouldn't affect the domestication level of a horse when added"
+	subtract infinity value from domestication level of {_e}
+	assert domestication level of {_e} is 1 with "infinity value should result in 1 when subtracted from the domestication level of a horse"
+	set domestication level of {_e} to infinity value
+	assert domestication level of {_e} is 2147483647 with "infinity value should set the domestication level of a horse to the max integer value"
+
+	# NaN values
+	add NaN value to max domestication level of {_e}
+	assert max domestication level of {_e} is 2147483647 with "NaN value should result in 2147483647 when added to the max domestication level of a horse"
+	set max domestication level of {_e} to NaN value
+	assert max domestication level of {_e} is 1 with "NaN value should result in 1 when used to set the max domestication level of a horse"
+	subtract NaN value from max domestication level of {_e}
+	assert max domestication level of {_e} is 1 with "NaN value should not allow the max domestication level of a horse to drop below 1"
+
+	add NaN value to domestication level of {_e}
+	assert domestication level of {_e} is 1 with "NaN value should result in 1 when used to change the domestication level of a horse"
+	set domestication level of {_e} to NaN value
+	assert domestication level of {_e} is 1 with "NaN value should result in 1 when used to set the domestication level of a horse"
+	subtract NaN value from domestication level of {_e}
+	assert domestication level of {_e} is 1 with "NaN value should result in 1 when used to change the domestication level of a horse"
+
+	# non-horse entity
+	assert max domestication level of {_z} is not set with "the max domestication of a non-horse should be null"
+	assert domestication level of {_z} is not set with "the domestication of a non-horse should be null"
+	set max domestication level of {_z} to 1
+	set domestication level of {_z} to 1
+	add 1 to max domestication level of {_z}
+	add 1 to domestication level of {_z}
+	subtract 1 from max domestication level of {_z}
+	subtract 1 from domestication level of {_z}
+	assert max domestication level of {_z} is not set with "changing the max domestication of a non-horse should do nothing"
+	assert domestication level of {_z} is not set with "changing the domestication of a non-horse should do nothing"
+
+	delete entity within {_e}
+	delete entity within {_z}