package io.gitlab.jfronny.muscript.ast.math;

import io.gitlab.jfronny.muscript.compiler.ExprWriter;
import io.gitlab.jfronny.muscript.compiler.Order;
import io.gitlab.jfronny.muscript.data.Scope;
import io.gitlab.jfronny.muscript.ast.Expr;
import io.gitlab.jfronny.muscript.ast.NumberExpr;
import io.gitlab.jfronny.muscript.ast.literal.NumberLiteral;

import java.io.IOException;

public class Power extends NumberExpr {
    private final NumberExpr base;
    private final NumberExpr exponent;

    public Power(int chStart, int chEnd, NumberExpr base, NumberExpr exponent) {
        super(Order.Exp, chStart, chEnd);
        this.base = base;
        this.exponent = exponent;
    }

    @Override
    public Double get(Scope dataRoot) {
        return Math.pow(base.get(dataRoot), exponent.get(dataRoot));
    }

    @Override
    public NumberExpr optimize() {
        NumberExpr base = this.base.optimize();
        NumberExpr exponent = this.exponent.optimize();
        if (base instanceof NumberLiteral litB && exponent instanceof NumberLiteral litE)
            return Expr.literal(chStart, chEnd, Math.pow(litB.value, litE.value));
        if (exponent instanceof NumberLiteral exp && base instanceof Multiply multiply) {
            if (multiply.multiplier instanceof NumberLiteral literal)
                return new Multiply(multiply.chStart, multiply.chEnd,
                        Expr.literal(chStart, chEnd, Math.pow(literal.value, exp.value)),
                        new Power(chStart, chEnd, multiply.multiplicand, exp));
            if (multiply.multiplicand instanceof NumberLiteral literal)
                return new Multiply(multiply.chStart, multiply.chEnd,
                        Expr.literal(chStart, chEnd, Math.pow(literal.value, exp.value)),
                        new Power(chStart, chEnd, multiply.multiplier, exp));
        }
        return new Power(chStart, chEnd, base, exponent);
    }

    @Override
    public void decompile(ExprWriter writer) throws IOException {
        parenthesize(base, writer, false);
        writer.append(" ^ ");
        parenthesize(exponent, writer, true);
    }

    @Override
    public boolean equals(Object obj) {
        return obj instanceof Power power && base.equals(power.base) && exponent.equals(power.exponent);
    }
}