WarpPI/core/src/main/java/it/cavallium/warppi/math/rules/dsl/patterns/NegativePattern.java

73 lines
1.9 KiB
Java

package it.cavallium.warppi.math.rules.dsl.patterns;
import it.cavallium.warppi.math.Function;
import it.cavallium.warppi.math.MathContext;
import it.cavallium.warppi.math.functions.Negative;
import it.cavallium.warppi.math.functions.Number;
import it.cavallium.warppi.math.rules.dsl.Pattern;
import it.cavallium.warppi.math.rules.dsl.VisitorPattern;
import java.math.BigDecimal;
import java.util.Map;
import java.util.Objects;
import java.util.stream.Stream;
/**
* Matches and generates the negative of another pattern.
*/
public class NegativePattern extends VisitorPattern {
private final Pattern inner;
public NegativePattern(final Pattern inner) {
this.inner = inner;
}
@Override
public Boolean visit(final Negative negative, final Map<String, Function> subFunctions) {
return inner.match(negative.getParameter(), subFunctions);
}
@Override
public Boolean visit(final Number number, final Map<String, Function> subFunctions) {
final BigDecimal value = number.getTerm();
if (value.signum() >= 0) {
return false;
}
final Number absoluteValue = new Number(number.getMathContext(), value.abs());
return inner.match(absoluteValue, subFunctions);
}
@Override
public Function replace(final MathContext mathContext, final Map<String, Function> subFunctions) {
final Function newInner = inner.replace(mathContext, subFunctions);
if (newInner instanceof Number) {
return ((Number) newInner).multiply(new Number(mathContext, -1));
} else {
return new Negative(
mathContext,
inner.replace(mathContext, subFunctions)
);
}
}
@Override
public Stream<SubFunctionPattern> getSubFunctions() {
return inner.getSubFunctions();
}
@Override
public boolean equals(final Object o) {
if (!(o instanceof NegativePattern)) {
return false;
}
final NegativePattern other = (NegativePattern) o;
return inner.equals(other.inner);
}
@Override
public int hashCode() {
return Objects.hash(inner);
}
}