//
//  RKObjectManager.h
//  RestKit
//
//  Created by Jeremy Ellison on 8/14/09.
//  Copyright 2009 Two Toasters. All rights reserved.
//

#import "../Network/Network.h"
#import "RKObjectMapper.h"
#import "RKObjectLoader.h"
#import "RKStaticRouter.h"

// Notifications
extern NSString* const RKDidEnterOfflineModeNotification;
extern NSString* const RKDidEnterOnlineModeNotification;

// TODO: Factor out into a protocol...
// insertObject:, deleteObject:, save, etc.
@class RKManagedObjectStore;

@interface RKObjectManager : NSObject {
	RKClient* _client;
	RKMappingFormat _format;
	RKObjectMapper* _mapper;
	NSObject<RKRouter>* _router;
	RKManagedObjectStore* _objectStore;		
	BOOL _isOnline;
}

/**
 * Return the globally shared instance of the object manager
 */
+ (RKObjectManager*)globalManager;

/**
 * Set the globally shared instance of the object manager
 */
+ (void)setGlobalManager:(RKObjectManager*)manager;

/**
 * Create and initialize a new object manager. If this is the first instance created
 * it will be set as the shared instance
 */
+ (RKObjectManager*)objectManagerWithBaseURL:(NSString*)baseURL;

/**
 * Initialize a new model manager instance
 */
- (id)initWithBaseURL:(NSString*)baseURL;

/**
 * The wire format to use for communications. Either RKMappingFormatXML or RKMappingFormatJSON.
 *
 * Defaults to RKMappingFormatJSON
 */
@property(nonatomic, assign) RKMappingFormat format;

/**
 * The REST client for this manager
 */
@property (nonatomic, retain) RKClient* client;

/**
 * Puts the manager into offline mode. Requests will not be sent.
 */
- (void)goOffline;

/**
 * Puts the manager into online mode. Requests will be sent.
 */
- (void)goOnline;

/**
 * True when we are in online mode
 */
- (BOOL)isOnline;

/**
 * Register a resource mapping from a domain model class to a JSON/XML element name
 */
- (void)registerClass:(Class<RKObjectMappable>)class forElementNamed:(NSString*)elementName;

/**
 * Mapper object responsible for mapping remote HTTP resources to Cocoa objects
 */
@property(nonatomic, readonly) RKObjectMapper* mapper;

/**
 * Routing object responsible for generating paths for objects and serializing
 * representations of the object for transport.
 *
 * Defaults to an instance of RKStaticRouter
 */
@property(nonatomic, retain) NSObject<RKRouter>* router;

/**
 * A Core Data backed object store for persisting objects that have been fetched from the Web
 */
@property(nonatomic, retain) RKManagedObjectStore* objectStore;

/**
 * Return an object loader request object ready to be sent. The method defaults to GET and the URL is relative to the
 * baseURL configured on the client.
 */
- (RKObjectLoader*)loaderWithResourcePath:(NSString*)resourcePath objectClass:(Class<RKObjectMappable>)objectClass delegate:(NSObject<RKObjectLoaderDelegate>*)delegate;

////////////////////////////////////////////////////////
// Registered Object Loaders

/**
 * These methods are suitable for loading remote payloads that encode type information into the payload. This enables
 * the mapping of complex payloads spanning multiple types (i.e. a search operation returning Articles & Comments in
 * one payload). Ruby on Rails JSON serialization is an example of such a conformant system.
 */
 
/**
 * Create and send an asynchronous GET request to load the objects at the resource path and call back the delegate
 * with the loaded objects. Remote objects will be mapped to local objects by consulting the element registrations
 * set on the mapper.
 */
- (RKObjectLoader*)loadObjectsAtResourcePath:(NSString*)resourcePath delegate:(NSObject<RKObjectLoaderDelegate>*)delegate;

/**
 * Create and send an asynchronous GET request to load the objects at the specified resource path with a dictionary
 * of query parameters to append to the URL and call back the delegate with the loaded objects. Remote objects will be mapped to 
 * local objects by consulting the element registrations set on the mapper.
 */
- (RKObjectLoader*)loadObjectsAtResourcePath:(NSString *)resourcePath queryParams:(NSDictionary*)queryParams delegate:(NSObject <RKObjectLoaderDelegate>*)delegate;

////////////////////////////////////////////////////////
// Explicit Object Loaders

/**
 * These methods are suitable for loading remote payloads where no type information is encoded into the payload. When
 * the request is completed, the resulting payload will be mapped into instances of the specified mappable object class.
 */

/**
 * Create and send an asynchronous GET request to load the objects at the resource path and call back the delegate
 * with the loaded objects. Remote objects will be mapped into instances of the specified object mappable class.
 */
- (RKObjectLoader*)loadObjectsAtResourcePath:(NSString*)resourcePath objectClass:(Class<RKObjectMappable>)objectClass delegate:(NSObject<RKObjectLoaderDelegate>*)delegate;

/**
 * Create and send an asynchronous GET request to load the objects at the specified resource path with a dictionary
 * of query parameters to append to the URL and call back the delegate with the loaded objects. Remote objects will be mapped into 
 * instances of the specified object mappable class.
 */
- (RKObjectLoader*)loadObjectsAtResourcePath:(NSString *)resourcePath queryParams:(NSDictionary*)queryParams objectClass:(Class<RKObjectMappable>)objectClass delegate:(NSObject <RKObjectLoaderDelegate>*)delegate;

////////////////////////////////////////////////////////
// Mappable object helpers

/**
 * Update a mappable model by loading its attributes from the web
 */
- (RKObjectLoader*)getObject:(NSObject<RKObjectMappable>*)object delegate:(NSObject<RKObjectLoaderDelegate>*)delegate;

/**
 * Create a remote mappable model by POSTing the attributes to the remote resource and loading the resulting objects from the payload
 */
- (RKObjectLoader*)postObject:(NSObject<RKObjectMappable>*)object delegate:(NSObject<RKObjectLoaderDelegate>*)delegate;

/**
 * Update a remote mappable model by PUTing the attributes to the remote resource and loading the resulting objects from the payload
 */
- (RKObjectLoader*)putObject:(NSObject<RKObjectMappable>*)object delegate:(NSObject<RKObjectLoaderDelegate>*)delegate;

/**
 * Delete the remote instance of a mappable model by performing an HTTP DELETE on the remote resource
 */
- (RKObjectLoader*)deleteObject:(NSObject<RKObjectMappable>*)object delegate:(NSObject<RKObjectLoaderDelegate>*)delegate;

@end