//
//  MPFactor.m
//  MathPad
//
//  Created by Kim Wittenburg on 09.10.14.
//  Copyright (c) 2014 Kim Wittenburg. All rights reserved.
//

#import "MPFactor.h"
#import "MPMathRules.h"

@implementation MPFactor {
    BOOL _multiplicationSymbolPresent;
}

- (instancetype)init
{
    self = [super init];
    if (self) {
        
    }
    return self;
}

- (instancetype)initWithTokenStream:(MPTokenStream *)tokenStream
{
    self = [self init];
    if (self) {
        [tokenStream beginIgnoringWhitespaceTokens];
        MPToken *token = tokenStream.currentToken;
        _multiplicationSymbolPresent = token.tokenType == MPMultiplicationSymbolToken;
        if (_multiplicationSymbolPresent) {
            [tokenStream currentTokenConsumed];
        }
        if (tokenStream.currentToken.tokenType == MPOperatorListToken) {
            _operatorChain = [[MPOperatorChain alloc] initWithTokenStream:tokenStream];
        }
        MPValueGroup *valueGroup = [[MPValueGroup alloc] initWithTokenStream:tokenStream];
        _value = [tokenStream consumeSuffixesForValue:valueGroup];
        [tokenStream endIgnoringOrAcceptingWhitespaceTokens];
    }
    return self;
}

- (BOOL)hasMultiplicationSymbol
{
    return _multiplicationSymbolPresent;
}

- (BOOL)validate:(NSError *__autoreleasing *)error
{
    if (self.operatorChain.numberOfOperators > [[MPMathRules sharedRules] maximumOperatorChainLengthInMultiplication]) {
        if (error) {
            *error = MPParseError(7,
                                  NSLocalizedString(@"Too many operators in Multiplication.", @"Error message. This is displayed when there are too many operators between a multiplication symbol and a value."),
                                  nil);
        }
        return NO;
    }
    return [self.value validate:error];
}

- (NSDecimalNumber *)evaluate
{
    NSDecimalNumber *value = [self.value evaluate];
    if ([value isNotEqualTo:[NSDecimalNumber notANumber]] && self.operatorChain) {
        value = [value decimalNumberByMultiplyingBy:[self.operatorChain evaluate]];
    }
    return value;
}

@end