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

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.*;
import io.gitlab.jfronny.muscript.ast.literal.NumberLiteral;
import io.gitlab.jfronny.muscript.ast.math.*;

import java.io.IOException;

public class Greater extends BoolExpr {
    public final NumberExpr left;
    public final NumberExpr right;

    public Greater(int chStart, int chEnd, NumberExpr left, NumberExpr right) {
        super(Order.Comparison, chStart, chEnd);
        this.left = left;
        this.right = right;
    }

    @Override
    public Boolean get(Scope dataRoot) {
        return left.get(dataRoot) > right.get(dataRoot);
    }

    @Override
    public BoolExpr optimize() {
        NumberExpr left = this.left.optimize();
        NumberExpr right = this.right.optimize();
        if (left instanceof NumberLiteral litL && right instanceof NumberLiteral litR)
            return Expr.literal(chStart, chEnd, litL.value > litR.value);
        if (left instanceof Divide divide)
            return new Greater(chStart, chEnd, divide.dividend, new Multiply(divide.chStart, divide.chEnd, right, divide.divisor)).optimize();
        if (left instanceof Invert invert)
            return new Greater(chStart, chEnd, new Invert(right.chStart, right.chEnd, right), invert.inner).optimize();
        if (left instanceof Minus minus)
            return new Greater(chStart, chEnd, minus.minuend, new Plus(minus.chStart, minus.chEnd, minus.subtrahend, right)).optimize();
        // Modulo is left out because it is too complicated for this naive impl
        // Multiply is left out since it would transform into a division and may be 0
        if (left instanceof Plus plus)
            return new Greater(chStart, chEnd, plus.augend, new Minus(plus.chStart, plus.chEnd, plus.addend, right)).optimize();
        // Power is left out because it can't be transformed cleanly either
        return new Greater(chStart, chEnd, left, right);
    }

    @Override
    public void decompile(ExprWriter writer) throws IOException {
        if (left instanceof NumberLiteral && !(right instanceof NumberLiteral)) {
            parenthesize(right, writer, false);
            writer.append(" < ");
            parenthesize(left, writer, true);
        } else {
            parenthesize(left, writer, false);
            writer.append(" > ");
            parenthesize(right, writer, true);
        }
    }

    @Override
    public boolean equals(Object obj) {
        return obj instanceof Greater greater && left.equals(greater.left) && right.equals(greater.right);
    }
}