package expression;

import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.List;

/**
 * @author Doschennikov Nikita (me@fymio.us)
 */
public class Square extends AbstractExpression {
    private final AbstractExpression operand;

    public Square(AbstractExpression operand) {
        this.operand = operand;
    }

    private static int squareInt(int n) {
        if (n == Integer.MIN_VALUE) throw new OverflowException("square");
        int result = n * n;
        // overflow check: result / n should == n (if n != 0)
        if (n != 0 && result / n != n) throw new OverflowException("square");
        return result;
    }

    @Override public int        evaluate(int x)               { return squareInt(operand.evaluate(x)); }
    @Override public int        evaluate(int x, int y, int z) { return squareInt(operand.evaluate(x,y,z)); }
    @Override public int        evaluate(List<Integer> vars)  { return squareInt(operand.evaluate(vars)); }
    @Override public BigInteger evaluateBi(List<BigInteger> vars) { return operand.evaluateBi(vars).pow(2); }
    @Override public BigDecimal evaluateBd(List<BigDecimal> vars) { return operand.evaluateBd(vars).pow(2); }

    @Override public String toString()     { return "(" + operand + ")²"; }

    @Override
    public String toMiniString() {
        String s = operand.toMiniString();
        boolean needParens = operand instanceof AbstractBinaryOperation
                || operand instanceof Cbrt
                || operand instanceof Sqrt
                || (s.startsWith("-") && (s.length() < 2 || !Character.isDigit(s.charAt(1))));
        return needParens ? "(" + s + ")²" : s + "²";
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj) return true;
        if (!(obj instanceof Square)) return false;
        return operand.equals(((Square) obj).operand);
    }

    @Override public int hashCode() { return operand.hashCode() ^ 0x53515232; }
}