//
//  MPRootFunction.m
//  MathPad
//
//  Created by Kim Wittenburg on 22.10.14.
//  Copyright (c) 2014 Kim Wittenburg. All rights reserved.
//

#import "MPRootFunction.h"

#import "MPExpressionTree.h"

@implementation MPRootFunction

MPFunctionAccessorImplementation(ExponentExpression, _exponentExpression)
MPFunctionAccessorImplementation(RadicantExpression, _radicantExpression)

- (NSArray *)childrenAccessors
{
    return @[@"exponentExpression", @"radicantExpression"];
}

- (BOOL)validate:(NSError *__autoreleasing *)error
{
    return [[self.exponentExpression parse] validate:error] && [[self.radicantExpression parse] validate:error];
}

- (NSDecimalNumber *)evaluate
{
    NSDecimalNumber *exponent = [[self.exponentExpression parse] evaluate];
    NSDecimalNumber *radicant = [[self.radicantExpression parse] evaluate];
    return [[NSDecimalNumber alloc] initWithDouble:pow(radicant.doubleValue, exponent.doubleValue)];
}

- (NSString *)description
{
    if (self.exponentExpression == nil) {
        return [NSString stringWithFormat:@"√%@", self.radicantExpression.description];
    }
    return [NSString stringWithFormat:@"pow(%@; %@)", self.radicantExpression.description, self.exponentExpression];
}

@end