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_YYModelPropertyMeta.h.m

2016-07-28  本文已影响21人  Laughingg
/// A property info in object model.
@interface _YYModelPropertyMeta : NSObject {
    @package
    NSString *_name;             ///< property's name
    YYEncodingType _type;        ///< property's type
    YYEncodingNSType _nsType;    ///< property's Foundation type
    BOOL _isCNumber;             ///< is c number type
    Class _cls;                  ///< property's class, or nil
    Class _genericCls;           ///< container's generic class, or nil if threr's no generic class
    SEL _getter;                 ///< getter, or nil if the instances cannot respond
    SEL _setter;                 ///< setter, or nil if the instances cannot respond
    BOOL _isKVCCompatible;       ///< YES if it can access with key-value coding
    BOOL _isStructAvailableForKeyedArchiver; ///< YES if the struct can encoded with keyed archiver/unarchiver
    BOOL _hasCustomClassFromDictionary; ///< class/generic class implements +modelCustomClassForDictionary:
    
    /*
     property->key:       _mappedToKey:key     _mappedToKeyPath:nil            _mappedToKeyArray:nil
     property->keyPath:   _mappedToKey:keyPath _mappedToKeyPath:keyPath(array) _mappedToKeyArray:nil
     property->keys:      _mappedToKey:keys[0] _mappedToKeyPath:nil/keyPath    _mappedToKeyArray:keys(array)
     */
    NSString *_mappedToKey;      ///< the key mapped to
    NSArray *_mappedToKeyPath;   ///< the key path mapped to (nil if the name is not key path)
    NSArray *_mappedToKeyArray;  ///< the key(NSString) or keyPath(NSArray) array (nil if not mapped to multiple keys)
    YYClassPropertyInfo *_info;  ///< property's info
    _YYModelPropertyMeta *_next; ///< next meta if there are multiple properties mapped to the same key.
}
@end


@implementation _YYModelPropertyMeta
+ (instancetype)metaWithClassInfo:(YYClassInfo *)classInfo propertyInfo:(YYClassPropertyInfo *)propertyInfo generic:(Class)generic {
    
    // support pseudo generic class with protocol name
    if (!generic && propertyInfo.protocols) {
        for (NSString *protocol in propertyInfo.protocols) {
            Class cls = objc_getClass(protocol.UTF8String);
            if (cls) {
                generic = cls;
                break;
            }
        }
    }
    
    _YYModelPropertyMeta *meta = [self new];
    meta->_name = propertyInfo.name;
    meta->_type = propertyInfo.type;
    meta->_info = propertyInfo;
    meta->_genericCls = generic;
    
    if ((meta->_type & YYEncodingTypeMask) == YYEncodingTypeObject) {
        meta->_nsType = YYClassGetNSType(propertyInfo.cls);
    } else {
        meta->_isCNumber = YYEncodingTypeIsCNumber(meta->_type);
    }
    if ((meta->_type & YYEncodingTypeMask) == YYEncodingTypeStruct) {
        /*
         It seems that NSKeyedUnarchiver cannot decode NSValue except these structs:
         */
        static NSSet *types = nil;
        static dispatch_once_t onceToken;
        dispatch_once(&onceToken, ^{
            NSMutableSet *set = [NSMutableSet new];
            // 32 bit
            [set addObject:@"{CGSize=ff}"];
            [set addObject:@"{CGPoint=ff}"];
            [set addObject:@"{CGRect={CGPoint=ff}{CGSize=ff}}"];
            [set addObject:@"{CGAffineTransform=ffffff}"];
            [set addObject:@"{UIEdgeInsets=ffff}"];
            [set addObject:@"{UIOffset=ff}"];
            // 64 bit
            [set addObject:@"{CGSize=dd}"];
            [set addObject:@"{CGPoint=dd}"];
            [set addObject:@"{CGRect={CGPoint=dd}{CGSize=dd}}"];
            [set addObject:@"{CGAffineTransform=dddddd}"];
            [set addObject:@"{UIEdgeInsets=dddd}"];
            [set addObject:@"{UIOffset=dd}"];
            types = set;
        });
        if ([types containsObject:propertyInfo.typeEncoding]) {
            meta->_isStructAvailableForKeyedArchiver = YES;
        }
    }
    meta->_cls = propertyInfo.cls;
    
    if (generic) {
        meta->_hasCustomClassFromDictionary = [generic respondsToSelector:@selector(modelCustomClassForDictionary:)];
    } else if (meta->_cls && meta->_nsType == YYEncodingTypeNSUnknown) {
        meta->_hasCustomClassFromDictionary = [meta->_cls respondsToSelector:@selector(modelCustomClassForDictionary:)];
    }
    
    if (propertyInfo.getter) {
        if ([classInfo.cls instancesRespondToSelector:propertyInfo.getter]) {
            meta->_getter = propertyInfo.getter;
        }
    }
    if (propertyInfo.setter) {
        if ([classInfo.cls instancesRespondToSelector:propertyInfo.setter]) {
            meta->_setter = propertyInfo.setter;
        }
    }
    
    if (meta->_getter && meta->_setter) {
        /*
         KVC invalid type:
         long double
         pointer (such as SEL/CoreFoundation object)
         */
        switch (meta->_type & YYEncodingTypeMask) {
            case YYEncodingTypeBool:
            case YYEncodingTypeInt8:
            case YYEncodingTypeUInt8:
            case YYEncodingTypeInt16:
            case YYEncodingTypeUInt16:
            case YYEncodingTypeInt32:
            case YYEncodingTypeUInt32:
            case YYEncodingTypeInt64:
            case YYEncodingTypeUInt64:
            case YYEncodingTypeFloat:
            case YYEncodingTypeDouble:
            case YYEncodingTypeObject:
            case YYEncodingTypeClass:
            case YYEncodingTypeBlock:
            case YYEncodingTypeStruct:
            case YYEncodingTypeUnion: {
                meta->_isKVCCompatible = YES;
            } break;
            default: break;
        }
    }
    
    return meta;
}
@end
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