#import "JSONModel+CoreData.h"

#import <objc/runtime.h>

#import <objc/message.h>

@implementation JSONModel(CoreData)

@implementation NSManagedObject(JSONModel)

+(NSString*)entityName

{

return nil;

}

+(instancetype)entityWithModel:(id<AbstractJSONModelProtocol>)model inContext:(NSManagedObjectContext*)context error:(NSError**)error

{

return [self entityWithDictionary: [model toDictionary]

inContext: context

error:error];

}

+(instancetype)entityWithDictionary:(NSDictionary*)dictionary inContext:(NSManagedObjectContext*)context error:(NSError**)error

{

NSManagedObject* entity = [NSEntityDescription

insertNewObjectForEntityForName: self.entityName?self.entityName:NSStringFromClass([self class])

inManagedObjectContext:context];

if (entity) {

if (![entity updateWithDictionary: dictionary error: error]) {

return nil;

}

}

return entity;

}

-(BOOL)updateWithDictionary:(NSDictionary*)dictionary error:(NSError**)error

{

//introspect managed object

Class class = [self class];

NSMutableDictionary* moProperties = [@{} mutableCopy];

while (class != [NSManagedObject class]) {

unsigned int propertyCount;

objc_property_t *properties = class_copyPropertyList(class, &propertyCount);

//loop over the class properties

for (unsigned int i = 0; i < propertyCount; i++) {

objc_property_t property = properties[i];

const char *propertyName = property_getName(property);

const char *attrs = property_getAttributes(property);

NSString* propertyAttributes = @(attrs);

NSScanner* scanner = [NSScanner scannerWithString: propertyAttributes];

NSString* propertyType = nil;

[scanner scanUpToString:@"T" intoString: nil];

[scanner scanString:@"T" intoString:nil];

//check if the property is an instance of a class

if ([scanner scanString:@"@\"" intoString: &propertyType]) {

[scanner scanUpToCharactersFromSet:[NSCharacterSet characterSetWithCharactersInString:@"\"<"]

intoString:&propertyType];

}

moProperties[@(propertyName)] = NSClassFromString(propertyType);

}

free(properties);

class = [class superclass];

}

//validate dictionary keys

NSArray* dictionaryKeys = [dictionary allKeys];

for (NSString* key in [moProperties allKeys]) {

if (![dictionaryKeys containsObject:key]) {

//unmatched key

if (error) {

*error = [JSONModelError errorInvalidDataWithTypeMismatch:[NSString stringWithFormat: @"Key \"%@\" not found in manged object's property list", key]];

}

return NO;

}

}

//copy values over

for (NSString* key in [moProperties allKeys]) {

id value = dictionary[key];

//exception classes - for core data should be NSDate by default

if ([[moProperties[key]class] isEqual:[NSDate class]]) {

SEL NSDateFromNSStringSelector = sel_registerName("NSDateFromNSString:");

if ([self respondsToSelector:NSDateFromNSStringSelector]) {

IMP methodImpl = [self methodForSelector:NSDateFromNSStringSelector];

NSDate * (*method)(id, SEL, NSString *) = (void *)methodImpl;

//transform the value

value = method(self, NSDateFromNSStringSelector, dictionary[key]);

} else {

value = [self __NSDateFromNSString: dictionary[key]];

}

}

//copy the value to the managed object

[self setValue:value forKey:key];

}

return YES;

}

#pragma mark - string <-> date

-(NSDate*)__NSDateFromNSString:(NSString*)string

{

NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];

string = [string stringByReplacingOccurrencesOfString:@":" withString:@""]; // this is such an ugly code, is this the only way?

[dateFormatter setDateFormat:@"yyyy-MM-dd'T'HHmmssZZZZ"];

return [dateFormatter dateFromString: string];

}