INTULocationManager.h

//
//  INTULocationManager.h
//
//  Copyright (c) 2014 Intuit Inc.
//
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//  a copy of this software and associated documentation files (the
//  "Software"), to deal in the Software without restriction, including
//  without limitation the rights to use, copy, modify, merge, publish,
//  distribute, sublicense, and/or sell copies of the Software, and to
//  permit persons to whom the Software is furnished to do so, subject to
//  the following conditions:
//
//  The above copyright notice and this permission notice shall be
//  included in all copies or substantial portions of the Software.
//
//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
//  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
//  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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#import <Foundation/Foundation.h>
#import <CoreLocation/CoreLocation.h>
#import "INTULocationRequestDefines.h"

/**
 An abstraction around CLLocationManager that provides a block-based asynchronous API for obtaining the device's location.
 This class will automatically start and stop system location services as needed to conserve battery.
 */
@interface INTULocationManager : NSObject

/** Returns YES if location services are enabled in the system settings, and the app has NOT been denied/restricted access. Returns NO otherwise. */
@property (nonatomic, readonly) BOOL locationServicesAvailable;

/** Returns the singleton instance of this class. */
+ (instancetype)sharedInstance;

/**
 Asynchronously requests the current location of the device using location services.
 
 @param desiredAccuracy The accuracy level desired (refers to the accuracy and recency of the location).
 @param timeout The maximum amount of time (in seconds) to wait for the desired accuracy before completing.
                If this value is 0.0, no timeout will be set (will wait indefinitely for success, unless request is force completed or canceled).
 @param block The block to execute upon success, failure, or timeout.
 
 @return The location request ID, which can be used to force early completion or cancel the request while it is in progress.
 */
- (INTULocationRequestID)requestLocationWithDesiredAccuracy:(INTULocationAccuracy)desiredAccuracy
                                                    timeout:(NSTimeInterval)timeout
                                                      block:(INTULocationRequestBlock)block;

/**
 Asynchronously requests the current location of the device using location services, optionally delaying the timeout countdown until the user has
 responded to the dialog requesting permission for this app to access location services.
 
 @param desiredAccuracy The accuracy level desired (refers to the accuracy and recency of the location).
 @param timeout The maximum amount of time (in seconds) to wait for the desired accuracy before completing.
                If this value is 0.0, no timeout will be set (will wait indefinitely for success, unless request is force completed or canceled).
 @param delayUntilAuthorized A flag specifying whether the timeout should only take effect after the user responds to the system prompt requesting
                             permission for this app to access location services. If YES, the timeout countdown will not begin until after the
                             app receives location services permissions. If NO, the timeout countdown begins immediately when calling this method. 
 @param block The block to execute upon success, failure, or timeout.
 
 @return The location request ID, which can be used to force early completion or cancel the request while it is in progress.
 */
- (INTULocationRequestID)requestLocationWithDesiredAccuracy:(INTULocationAccuracy)desiredAccuracy
                                                    timeout:(NSTimeInterval)timeout
                                       delayUntilAuthorized:(BOOL)delayUntilAuthorized
                                                      block:(INTULocationRequestBlock)block;

/**
 Creates a subscription for location updates that will execute the block once per update indefinitely (until canceled), regardless of the accuracy of each location.
 If an error occurs, the block will execute with a status other than INTULocationStatusSuccess, and the subscription will be canceled automatically.
 
 @param block The block to execute every time an updated location is available. 
              The status will be INTULocationStatusSuccess unless an error occurred; it will never be INTULocationStatusTimedOut.
 
 @return The location request ID, which can be used to cancel the subscription of location updates to this block.
 */
- (INTULocationRequestID)subscribeToLocationUpdatesWithBlock:(INTULocationRequestBlock)block;

/** Immediately forces completion of the location request with the given requestID (if it exists), and executes the original request block with the results.
    For one-time location requests, this is effectively a manual timeout, and will result in the request completing with status INTULocationStatusTimedOut.
    If the requestID corresponds to a subscription, then the subscription will simply be canceled. */
- (void)forceCompleteLocationRequest:(INTULocationRequestID)requestID;

/** Immediately cancels the location request (or subscription) with the given requestID (if it exists), without executing the original request block. */
- (void)cancelLocationRequest:(INTULocationRequestID)requestID;

@end