#import <Foundation/Foundation.h>

@class GGLConfiguration;

/**
 * Main entry point for Google API core configuration. Google services such as AdMob, Analytics,
 * AppInvite, CloudMessaging, SignIn, etc can be configured via this class and its categories.
 * See GGLContext+ServiceName for details on the individual APIs. Generally, you will import those
 * files directly rather than import the GGLContext.h header itself.
 *
 * Once the appropriate categories are imported, you can configure all services via the
 * |configureWithError:| method, for example:
 *
 * <pre>
 * NSError* configureError;
 * [[GGLContext sharedInstance] configureWithError: &configureError];
 * if (configureError != nil) {
 *   NSLog(@"Error configuring the Google context: %@", configureError);
 * }
 * </pre>
 *
 * The method |configureWithError:| will read from the file GoogleServices-Info.plist bundled with
 * your app target for the keys to configure each individual API. To generate your
 * GoogleServices-Info.plist, please go to https://developers.google.com/mobile/add
 *
 * @see GGLContext (AdMob)
 * @see GGLContext (Analytics)
 * @see GGLContext (AppInvite)
 * @see GGLContext (CloudMessaging)
 * @see GGLContext (SignIn)
 */
@interface GGLContext : NSObject

/**
 * The configuration details for various Google APIs.
 */
@property(nonatomic, readonly, strong) GGLConfiguration *configuration;

/**
 * Get the shared instance of the GGLContext.
 * @return the shared instance
 */
+ (instancetype)sharedInstance;

/**
 * Configures all the Google services integrated. This method should be called after the app is
 * launched and before using other Google services. The services will be available in categories
 * that extend this class, such as GGLContext+AdMob.
 *
 * @param error Pointer to an NSError that can be used an out param to report the status of this
 * operation. After the call the error object will be nil if the operation is succesful,
 * otherwise contains an appropriate NSError value. Parameter cannot be passed as nil
 *
 * @warning error must not be nil.
 *
 */
- (void)configureWithError:(NSError **)error;

@end