//
//  RQBaseModel.m
//  RQCommon
//
//  Created by 张嵘 on 2018/11/14.
//  Copyright © 2018 张嵘. All rights reserved.
//

#import "RQBaseModel.h"
#import "RQReflection.h"
#import "RQEXTRuntimeExtensions.h"

// Used to cache the reflection performed in +propertyKeys.
static void *RQObjectCachedPropertyKeysKey = &RQObjectCachedPropertyKeysKey;

// Validates a value for an object and sets it if necessary.
//
// obj         - The object for which the value is being validated. This value
//               must not be nil.
// key         - The name of one of `obj`s properties. This value must not be
//               nil.
// value       - The new value for the property identified by `key`.
// forceUpdate - If set to `YES`, the value is being updated even if validating
//               it did not change it.
// error       - If not NULL, this may be set to any error that occurs during
//               validation
//
// Returns YES if `value` could be validated and set, or NO if an error
// occurred.
static BOOL SBValidateAndSetValue(id obj, NSString *key, id value, BOOL forceUpdate, NSError **error) {
	// Mark this as being autoreleased, because validateValue may return
	// a new object to be stored in this variable (and we don't want ARC to
	// double-free or leak the old or new values).
	__autoreleasing id validatedValue = value;
	
	@try {
		if (![obj validateValue:&validatedValue forKey:key error:error]) return NO;
		
		if (forceUpdate || value != validatedValue) {
			[obj setValue:validatedValue forKey:key];
		}
		
		return YES;
	} @catch (NSException *ex) {
		NSLog(@"*** Caught exception setting key \"%@\" : %@", key, ex);
		
		// Fail fast in Debug builds.
#if DEBUG
		@throw ex;
#else
		if (error != NULL) {
			*error = [NSError rq_modelErrorWithException:ex];
		}
		
		return NO;
#endif
	}
}

@implementation RQBaseModel
/// 将 JSON (NSData,NSString,NSDictionary) 转换为 Model
+ (instancetype)modelWithJSON:(id)json { return [self yy_modelWithJSON:json]; }

/// json-array 转 模型-数组
+ (NSArray *)modelArrayWithJSON:(id)json {
	return [NSArray yy_modelArrayWithClass:[self class] json:json];
}

/// 字典转模型
+ (instancetype)modelWithDictionary:(NSDictionary *)dictionary{
	return [self yy_modelWithDictionary:dictionary];
}

- (id)toJSONObject { return [self yy_modelToJSONObject]; }
- (NSData *)toJSONData { return [self yy_modelToJSONData]; }
- (NSString *)toJSONString { return [self yy_modelToJSONString]; }



/// Coding/Copying/hash/equal
- (void)encodeWithCoder:(NSCoder *)aCoder { [self yy_modelEncodeWithCoder:aCoder]; }
- (id)initWithCoder:(NSCoder *)aDecoder { return [self yy_modelInitWithCoder:aDecoder]; }
- (id)copyWithZone:(NSZone *)zone { return [self yy_modelCopy]; }
- (NSUInteger)hash { return [self yy_modelHash]; }
- (BOOL)isEqual:(id)object { return [self yy_modelIsEqual:object]; }

/// Properties optional
- (void)setValue:(id)value forUndefinedKey:(NSString *)key { }

/// desc
- (NSString *)description { return [self yy_modelDescription]; }





+ (NSSet *)propertyKeys {
	NSSet *cachedKeys = objc_getAssociatedObject(self, RQObjectCachedPropertyKeysKey);
	if (cachedKeys != nil) return cachedKeys;
	
	NSMutableSet *keys = [NSMutableSet set];
	
	[self enumeratePropertiesUsingBlock:^(objc_property_t property, BOOL *stop) {
		rq_propertyAttributes *attributes = rq_copyPropertyAttributes(property);
		@onExit {
			free(attributes);
		};
		
		if (attributes->readonly && attributes->ivar == NULL) return;
		
		NSString *key = @(property_getName(property));
		[keys addObject:key];
	}];
	
	// It doesn't really matter if we replace another thread's work, since we do
	// it atomically and the result should be the same.
	objc_setAssociatedObject(self, RQObjectCachedPropertyKeysKey, keys, OBJC_ASSOCIATION_COPY);
	
	return keys;
}

- (NSDictionary *)dictionaryValue {
	return [self dictionaryWithValuesForKeys:self.class.propertyKeys.allObjects];
}



#pragma mark Reflection
+ (void)enumeratePropertiesUsingBlock:(void (^)(objc_property_t property, BOOL *stop))block {
	Class cls = self;
	BOOL stop = NO;
	
	while (!stop && ![cls isEqual:RQBaseModel.class]) {
		unsigned count = 0;
		objc_property_t *properties = class_copyPropertyList(cls, &count);
		
		cls = cls.superclass;
		if (properties == NULL) continue;
		
		@onExit {
			free(properties);
		};
		
		for (unsigned i = 0; i < count; i++) {
			block(properties[i], &stop);
			if (stop) break;
		}
	}
}

#pragma mark Merging
- (void)mergeValueForKey:(NSString *)key fromModel:(RQBaseModel *)model {
	NSParameterAssert(key != nil);
	
	SEL selector = RQSelectorWithCapitalizedKeyPattern("merge", key, "FromModel:");
	if (![self respondsToSelector:selector]) {
		if (model != nil) {
			[self setValue:[model valueForKey:key] forKey:key];
		}
		return;
	}
	
	NSInvocation *invocation = [NSInvocation invocationWithMethodSignature:[self methodSignatureForSelector:selector]];
	invocation.target = self;
	invocation.selector = selector;
	
	[invocation setArgument:&model atIndex:2];
	[invocation invoke];
}

- (void)mergeValuesForKeysFromModel:(RQBaseModel *)model {
	NSSet *propertyKeys = model.class.propertyKeys;
	for (NSString *key in self.class.propertyKeys) {
		if (![propertyKeys containsObject:key]) continue;
		
		[self mergeValueForKey:key fromModel:model];
	}
}


#pragma mark Validation

- (BOOL)validate:(NSError **)error {
	for (NSString *key in self.class.propertyKeys) {
		id value = [self valueForKey:key];
		BOOL success = SBValidateAndSetValue(self, key, value, NO, error);
		if (!success) return NO;
	}
	return YES;
}

@end