Form Validation

PSFormValidation.h

#import <Foundation/Foundation.h>

extern NSString* const PSFormValidationErrorDomain;

typedef NS_ENUM(NSInteger, PSFormValidationError) {
    PSFormValidationErrorUndefined = 0,
    PSFormValidationErrorEmailEmpty,
    PSFormValidationErrorUsernameEmpty,
    PSFormValidationErrorPasswordEmpty,
    PSFormValidationErrorPasswordTooShort,
    PSFormValidationErrorPasswordTooLong,
    PSFormValidationErrorConfirmPasswordEmpty,
    PSFormValidationErrorConfirmPasswordDoesNotMatch
};

@interface PSFormValidator : NSObject

- (BOOL)validateEmail:(id*)value error:(NSError* __autoreleasing*)error;
- (BOOL)validateUsername:(id*)value error:(NSError* __autoreleasing*)error;
- (BOOL)validatePassword:(id*)value error:(NSError* __autoreleasing*)error;
- (BOOL)validatePasswordConfirmation:(id*)confirmPassword password:(id*)password error:(NSError* __autoreleasing*)error; // is not KVC compatible

@end

PSFormValidation.m

#import "PSFormValidator.h"

NSString* const PSFormValidationErrorDomain = @"PSValidationErrorDomain";

@implementation PSFormValidator

- (BOOL)validateEmail:(id*)value error:(NSError* __autoreleasing*)error
{
    if ((*value == nil) || ([*value length] == 0))
    {
        if (error != NULL)
        {
            NSString* errorString = L(@"%sign_up_error_mail");
            NSDictionary* userInfoDict = @{ NSLocalizedDescriptionKey: errorString };
            *error = [[NSError alloc] initWithDomain:PSFormValidationErrorDomain
                                                code:PSFormValidationErrorEmailEmpty
                                            userInfo:userInfoDict];
        }
        
        return NO;
    }
    
    return YES;
}

- (BOOL)validateUsername:(id*)value error:(NSError* __autoreleasing*)error
{
    if ((*value == nil) || ([*value length] == 0))
    {
        if (error != NULL)
        {
            NSString* errorString = L(@"%sign_up_error_username");
            NSDictionary* userInfoDict = @{ NSLocalizedDescriptionKey: errorString };
            *error = [[NSError alloc] initWithDomain:PSFormValidationErrorDomain
                                                code:PSFormValidationErrorUsernameEmpty
                                            userInfo:userInfoDict];
        }
        
        return NO;
    }
    
    return YES;
}

- (BOOL)validatePassword:(id*)value error:(NSError* __autoreleasing*)error
{
    if ((*value == nil) || ([*value length] == 0))
    {
        if (error != NULL)
        {
            *error = [[NSError alloc] initWithDomain:PSFormValidationErrorDomain
                                                code:PSFormValidationErrorPasswordEmpty
                                            userInfo:@{ NSLocalizedDescriptionKey: L(@"%sign_up_error_password_empty") }];
        }
        
        return NO;
    }
    
    if ([*value length] < 6)
    {
        if (error != NULL)
        {
            *error = [[NSError alloc] initWithDomain:PSFormValidationErrorDomain
                                                code:PSFormValidationErrorPasswordTooShort
                                            userInfo:@{ NSLocalizedDescriptionKey: L(@"%sign_up_error_password_short") }];
        }
        
        return NO;
    }
    
    if ([*value length] > 20)
    {
        if (error != NULL)
        {
            *error = [[NSError alloc] initWithDomain:PSFormValidationErrorDomain
                                                code:PSFormValidationErrorPasswordTooLong
                                            userInfo:@{ NSLocalizedDescriptionKey: L(@"%sign_up_error_password_long") }];
        }
        
        return NO;
    }

    
    return YES;
}

- (BOOL)validatePasswordConfirmation:(id*)confirmPassword password:(id*)password error:(NSError* __autoreleasing*)error;
{
    if ((*confirmPassword == nil) || ([*confirmPassword length] == 0))
    {
        if (error != NULL)
        {
            *error = [[NSError alloc] initWithDomain:PSFormValidationErrorDomain
                                                code:PSFormValidationErrorConfirmPasswordEmpty
                                            userInfo:@{ NSLocalizedDescriptionKey: L(@"%sign_up_error_confirm_password_empty") }];
        }
        
        return NO;
    }
    
    if (![*confirmPassword isEqualToString:*password])
    {
        if (error != NULL)
        {
            *error = [[NSError alloc] initWithDomain:PSFormValidationErrorDomain
                                                code:PSFormValidationErrorConfirmPasswordDoesNotMatch
                                            userInfo:@{ NSLocalizedDescriptionKey: L(@"%sign_up_error_password_not_match") }];
        }
        
        return NO;
    }
    
    return YES;
}

@end