Add support for a negation/fail check on CondChance

src/main/java/ch/njol/skript/conditions/CondChance.java

@@ -1,58 +1,81 @@
 package ch.njol.skript.conditions;
 
-import org.bukkit.event.Event;
-import org.jetbrains.annotations.Nullable;
-
 import ch.njol.skript.Skript;
 import ch.njol.skript.doc.Description;
-import ch.njol.skript.doc.Examples;
+import ch.njol.skript.doc.Example;
 import ch.njol.skript.doc.Name;
 import ch.njol.skript.doc.Since;
 import ch.njol.skript.lang.Condition;
 import ch.njol.skript.lang.Expression;
+import ch.njol.skript.lang.Literal;
+import ch.njol.skript.lang.SimplifiedCondition;
 import ch.njol.skript.lang.SkriptParser.ParseResult;
 import ch.njol.util.Kleenean;
+import org.bukkit.event.Event;
+import org.jetbrains.annotations.Nullable;
 
-/**
- * @author Peter Güttinger
- */
 @Name("Chance")
-@Description({"A condition that randomly succeeds or fails.",
-		"Valid values are between 0% and 100%, or if the percent sign is omitted between 0 and 1."})
-@Examples({"chance of 50%:",
-		"\tdrop a diamond",
-		"chance of {chance}% # {chance} between 0 and 100",
-		"chance of {chance} # {chance} between 0 and 1"})
-@Since("1.0")
+@Description("""
+	A condition that randomly succeeds or fails.
+	Valid values are between 0% and 100%, or if the percent sign is omitted, between 0 and 1.
+	""")
+@Example("""
+	chance of 50%:
+		drop a diamond at location(100, 100, 100, "world')
+	""")
+@Example("chance of {chance}% # {chance} between 0 and 100")
+@Example("chance of {chance} # {chance} between 0 and 1")
+@Example("""
+	if chance of 99% fails:
+		broadcast "Haha loser! *points and laughs*"
+	""")
+@Since("1.0, INSERT VERSION (chance fails)")
 public class CondChance extends Condition {
 
 	static {
-		Skript.registerCondition(CondChance.class, "chance of %number%(1¦\\%|)");
+		Skript.registerCondition(CondChance.class, "chance of %number%(1:\\%|) [fail:(fails|failed)]");
 	}
-
-	@SuppressWarnings("null")
+
 	private Expression<Number> chance;
 	private boolean percent;
-
-	@SuppressWarnings({"unchecked", "null"})
+
 	@Override
-	public boolean init(final Expression<?>[] exprs, final int matchedPattern, final Kleenean isDelayed, final ParseResult parser) {
+	public boolean init(Expression<?>[] exprs, int matchedPattern, Kleenean isDelayed, ParseResult parseResult) {
+		//noinspection unchecked
 		chance = (Expression<Number>) exprs[0];
-		percent = parser.mark == 1;
+		percent = parseResult.mark == 1;
+		setNegated(parseResult.hasTag("fail"));
 		return true;
 	}
 
 	@Override
-	public boolean check(final Event e) {
-		final Number n = chance.getSingle(e);
-		if (n == null)
+	public boolean check(Event event) {
+		Number chance = this.chance.getSingle(event);
+		if (chance == null)
 			return false;
-		return Math.random() < (percent ? n.doubleValue() / 100 : n.doubleValue());
+		boolean result = Math.random() < (percent ? chance.doubleValue() / 100 : chance.doubleValue());
+		return result == !isNegated();
 	}
-	
+
 	@Override
-	public String toString(final @Nullable Event e, final boolean debug) {
-		return "chance of " + chance.toString(e, debug) + (percent ? "%" : "");
+	public Condition simplify() {
+		if (chance instanceof Literal<Number> litChance) {
+			Number chance = litChance.getSingle();
+			// We can only simplify if the provided value <= 0% or >= 100% (or 1)
+			// as this eliminates the random element and will always evaluate the same.
+			double maxValue = percent ? 100 : 1;
+			if (chance.doubleValue() >= maxValue || chance.doubleValue() <= 0)
+				return SimplifiedCondition.fromCondition(this);
+		}
+		return this;
 	}
-
+
+	@Override
+	public String toString(@Nullable Event event, boolean debug) {
+		String baseString = "chance of " + chance.toString(event, debug) + (percent ? "%" : "");
+		if (isNegated())
+			baseString += " failed";
+		return baseString;
+	}
+
 }