PFQuery+IsCache

PFQuery+IsCache

typedef void (^fg_PFArrayResultBlock)(NSArray *PF_NULLABLE_S objects, NSError *PF_NULLABLE_S error, BOOL isCache, BOOL done);

@interface PFQuery (IsCache)
- (void)fg_findObjectsInBackgroundWithBlock:(PF_NULLABLE fg_PFArrayResultBlock)block
						  willLoadFromCache:(void (^ __nullable)())willLoadFromCache
						willLoadFromNetwork:(void  (^ __nullable)())willLoadFromNetwork;
@end


@implementation PFQuery (IsCache)

- (void)fg_findObjectsInBackgroundWithBlock:(PF_NULLABLE fg_PFArrayResultBlock)block
						  willLoadFromCache:(void (^)())willLoadFromCache
						willLoadFromNetwork:(void (^)())willLoadFromNetwork
{
	PFCachePolicy cachePolicy = self.cachePolicy;
	if(cachePolicy == kPFCachePolicyCacheOnly || cachePolicy == kPFCachePolicyNetworkOnly || cachePolicy == kPFCachePolicyIgnoreCache)
	{
		if(cachePolicy == kPFCachePolicyCacheOnly){
			if(willLoadFromCache)
				willLoadFromCache();
		}
		else {
			if(willLoadFromNetwork)
				willLoadFromNetwork();
		}
		
		[self findObjectsInBackgroundWithBlock:^(NSArray *objects,NSError *error) {
			BOOL isCache = (cachePolicy == kPFCachePolicyCacheOnly);
			if(block)
				block(objects, error, isCache, true);
		}];
	}
	else if(cachePolicy == kPFCachePolicyCacheElseNetwork || cachePolicy == kPFCachePolicyCacheThenNetwork) {
		self.cachePolicy = kPFCachePolicyCacheOnly;
		
		if(willLoadFromCache)
			willLoadFromCache();
		
		[self findObjectsInBackgroundWithBlock:^(NSArray *objects,NSError *error) {
			BOOL done = (objects && cachePolicy == kPFCachePolicyCacheElseNetwork);
			if(block)
				block(objects, error, true, done);
			
			if(! done || cachePolicy == kPFCachePolicyCacheThenNetwork) {
				self.cachePolicy = kPFCachePolicyNetworkOnly;
				
				if(willLoadFromNetwork)
					willLoadFromNetwork();
				
				[self findObjectsInBackgroundWithBlock:^(NSArray *objects,NSError *error) {
					if(block)
						block(objects, error, false, true);
				}];
			}
		}];
	}
	else if(cachePolicy == kPFCachePolicyNetworkElseCache) {
		self.cachePolicy = kPFCachePolicyNetworkOnly;
		
		if(willLoadFromNetwork)
			willLoadFromNetwork();
		
		[self findObjectsInBackgroundWithBlock:^(NSArray *objects,NSError *error) {
			BOOL done = (objects != nil);
			if(block)
				block(objects, error, false, done);
			if(! done) {
				self.cachePolicy = kPFCachePolicyCacheOnly;
				
				if(willLoadFromCache)
					willLoadFromCache();
				
				[self findObjectsInBackgroundWithBlock:^(NSArray *objects,NSError *error) {
					if(block)
						block(objects, error, true, true);
				}];
			}
		}];
	}
}

@end