/*
 * Copyright 2010 Facebook
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *    http://www.apache.org/licenses/LICENSE-2.0
 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#import <UIKit/UIKit.h>
#import "FBSession.h"
#import "FBGraphUser.h"

@protocol FBLoginViewDelegate;

/*!
 @class FBLoginView
 @abstract FBLoginView is a custom UIView that renders a button to login or logout based on the
  state of `FBSession.activeSession`
 
 @discussion This view is closely associated with `FBSession.activeSession`. Upon initialization,
  it will attempt to open an active session without UI if the current active session is not open.
 
  The FBLoginView instance also monitors for changes to the active session.
 */
@interface FBLoginView : UIView

/*!
 @abstract
 The permissions to login with.  Defaults to nil, meaning basic permissions.
 
 @discussion Methods and properties that specify permissions without a read or publish
 qualification are deprecated; use of a read-qualified or publish-qualified alternative is preferred.
 */
@property (readwrite, copy) NSArray *permissions __attribute__((deprecated));

/*!
 @abstract
 The read permissions to request if the user logs in via this view.
 
 @discussion
 Note, that if read permissions are specified, then publish permissions should not be specified.
 */
@property (nonatomic, copy) NSArray *readPermissions;

/*!
 @abstract
 The publish permissions to request if the user logs in via this view.
 
 @discussion
 Note, that a defaultAudience value of FBSessionDefaultAudienceOnlyMe, FBSessionDefaultAudienceEveryone, or
 FBSessionDefaultAudienceFriends should be set if publish permissions are specified. Additionally, when publish
 permissions are specified, then read should not be specified.
 */
@property (nonatomic, copy) NSArray *publishPermissions;

/*!
 @abstract
 The default audience to use, if publish permissions are requested at login time.
 */
@property (nonatomic, assign) FBSessionDefaultAudience defaultAudience;


/*!
 @abstract
 Initializes and returns an `FBLoginView` object.  The underlying session has basic permissions granted to it.
 */
- (id)init;

/*!
 @method
 
 @abstract
 Initializes and returns an `FBLoginView` object constructed with the specified permissions.
 
 @param permissions  An array of strings representing the permissions to request during the
 authentication flow. A value of nil will indicates basic permissions. 
 
 @discussion Methods and properties that specify permissions without a read or publish
 qualification are deprecated; use of a read-qualified or publish-qualified alternative is preferred.
 */
- (id)initWithPermissions:(NSArray *)permissions __attribute__((deprecated));

/*!
 @method
 
 @abstract
 Initializes and returns an `FBLoginView` object constructed with the specified permissions.
 
 @param readPermissions  An array of strings representing the read permissions to request during the
 authentication flow. A value of nil will indicates basic permissions.
 
 */
- (id)initWithReadPermissions:(NSArray *)readPermissions;

/*!
 @method
 
 @abstract
 Initializes and returns an `FBLoginView` object constructed with the specified permissions.
 
 @param publishPermissions  An array of strings representing the publish permissions to request during the
 authentication flow. 
 
 @param defaultAudience  An audience for published posts; note that FBSessionDefaultAudienceNone is not valid
 for permission requests that include publish or manage permissions.
 
 */
- (id)initWithPublishPermissions:(NSArray *)publishPermissions
                 defaultAudience:(FBSessionDefaultAudience)defaultAudience;

/*!
 @abstract
 The delegate object that receives updates for selection and display control.
 */
@property (nonatomic, assign) IBOutlet id<FBLoginViewDelegate> delegate;

@end

/*!
 @protocol 
 
 @abstract
 The `FBLoginViewDelegate` protocol defines the methods used to receive event 
 notifications from `FBLoginView` objects.
 */
@protocol FBLoginViewDelegate <NSObject>

@optional

/*!
 @abstract
 Tells the delegate that the view is now in logged in mode
 
 @param loginView   The login view that transitioned its view mode
 */
- (void)loginViewShowingLoggedInUser:(FBLoginView *)loginView;

/*!
 @abstract
 Tells the delegate that the view is has now fetched user info

 @param loginView   The login view that transitioned its view mode
 
 @param user        The user info object describing the logged in user
 */
- (void)loginViewFetchedUserInfo:(FBLoginView *)loginView
                            user:(id<FBGraphUser>)user;

/*!
 @abstract
 Tells the delegate that the view is now in logged out mode
 
 @param loginView   The login view that transitioned its view mode
 */
- (void)loginViewShowingLoggedOutUser:(FBLoginView *)loginView;

/*!
 @abstract
 Tells the delegate that there is a communication or authorization error.
 
 @param loginView           The login view that transitioned its view mode
 @param error               An error object containing details of the error.
 @discussion See https://developers.facebook.com/docs/technical-guides/iossdk/errors/
 for error handling best practices.
 */
- (void)loginView:(FBLoginView *)loginView
      handleError:(NSError *)error;

@end