Added distance method

Example_Swift/Podfile

 source 'https://github.com/CocoaPods/Specs.git'
 use_frameworks!
 
-target ‘Example_Swift’ do
-    pod 'CedarMaps'
+target 'Example_Swift' do
+    pod 'CedarMaps' 
 end

Pod/Classes/CSMapKit.h

@@ -9,6 +9,7 @@
 @import CoreLocation;
 
 @class CSQueryParameters;
+@class CSDistancePoints;
 
 /* A CSMapKit is used to display map tiles from a network-based map hosted on CedarMaps as well as getting geocoding data from server.
  * Maps should be referenced by their map ID.
@@ -20,6 +21,8 @@
 
 - (instancetype)initWithMapID:(NSString *)mapID;
 - (void)styleURLWithCompletion:(void (^) (NSURL *url))completion;
+
+- (void)distanceBetweenPoints:(CSDistancePoints *)points withCompletion:(void (^) (NSArray *results, NSError *error))completion;
 - (void)forwardGeocodingWithQueryString:(NSString *)query
                              parameters:(CSQueryParameters *)parameters
                              completion:(void (^)(NSArray *results, NSError *error))completion;
@@ -38,3 +41,11 @@
 - (void)addLocationWithCoordinate:(CLLocationCoordinate2D)coordinate;
 
 @end
+
+#pragma mark
+
+@interface CSDistancePoints: NSObject
+
+- (void)addCoordinatePairWithDeparture:(CLLocationCoordinate2D)departure destination:(CLLocationCoordinate2D)destination;
+
+@end

Pod/Classes/CSMapKit.m

@@ -23,6 +23,14 @@
 
 @end
 
+#pragma mark - CSDistancePoints Private Interface
+
+@interface CSDistancePoints ()
+
+@property (nonatomic, strong) NSMutableString *pointsDesc;
+
+@end
+
 #pragma mark - CSMapSource Private Interface
 
 @interface CSMapKit ()
@@ -47,7 +55,7 @@
 #pragma mark StyleURL
 
 - (void)styleURLWithCompletion:(void (^) (NSURL *url))completion {
-
+    
     [[CSAuthenticationManager sharedManager] savedAccessToken:^(NSString *token) {
         NSString *tileJSONURLString = [NSString stringWithFormat:@"%@/styles/%@.json", [[CSAuthenticationManager sharedManager] baseURL] , self.mapID];
         if (token && token.length > 0) {
@@ -60,13 +68,67 @@
     }];
 }
 
+#pragma mark Distance
+
+- (void)distanceBetweenPoints:(CSDistancePoints *)points withCompletion:(void (^) (NSArray *results, NSError *error))completion {
+    
+    NSString *arguments = @"";
+    if (points.pointsDesc.length > 0 && [[points.pointsDesc substringFromIndex:points.pointsDesc.length-1] isEqualToString:@"/"]) {
+        arguments = [points.pointsDesc substringToIndex:points.pointsDesc.length - 1];
+    }
+    
+    NSMutableString *URLString = [NSMutableString stringWithFormat:@"%@/distance/cedarmaps.driving/%@", [[CSAuthenticationManager sharedManager] baseURL], arguments];
+    NSURL *URL = [NSURL URLWithString:[URLString stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];
+    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:URL];
+    
+    [[CSAuthenticationManager sharedManager] savedAccessToken:^(NSString *token) {
+        if (token) {
+            [request setValue:[NSString stringWithFormat:@"Bearer %@", token] forHTTPHeaderField:@"Authorization"];
+            
+            [[[NSURLSession sharedSession] dataTaskWithRequest:request completionHandler:^(NSData * _Nullable data, NSURLResponse * _Nullable response, NSError * _Nullable error) {
+                
+                if ([(NSHTTPURLResponse *)response statusCode] == HTTP_401_NOT_AUTHORIZED) {
+                    
+                    NSString *description = NSLocalizedString(INVALID_CREDINTIAL, @"");
+                    NSError *responseError = [NSError errorWithDomain:NSCocoaErrorDomain code:kCFURLErrorUserCancelledAuthentication userInfo:@{NSLocalizedDescriptionKey: description}];
+                    
+                    completion(nil, responseError);
+                } else {
+                    if (error != nil) {
+                        completion(nil, error);
+                    } else {
+                        NSError *serializationError;
+                        NSDictionary *json = [NSJSONSerialization JSONObjectWithData:data options:0 error:&serializationError];
+                        if (serializationError == nil) {
+                            NSArray *output = [NSArray array];
+                            if ([json.allKeys containsObject:@"result"]) {
+                                NSArray *results = [[json objectForKey:@"result"] objectForKey:@"routes"];
+                                output = results;
+                            }
+                            completion(output, nil);
+                        }
+                        else {
+                            completion(nil, serializationError);
+                        }
+                    }
+                }
+            }] resume];
+        } else {
+            NSString *description = NSLocalizedString(TOKEN_NOT_PROVIDED, @"");
+            NSError *error = [[NSError alloc] initWithDomain:NSCocoaErrorDomain code:TOKEN_NOT_PROVIDED_CODE userInfo:@{NSLocalizedDescriptionKey: description}];
+            completion(nil, error);
+        }
+    }];
+    
+}
+
 #pragma mark Geocoding
 
 - (void)forwardGeocodingWithQueryString:(NSString *)query
                              parameters:(CSQueryParameters *)parameters
                              completion:(void (^)(NSArray *results, NSError *error))completion
 {
-
+    
     NSMutableString *URLString = [NSMutableString stringWithFormat:@"%@/geocode/%@/%@", [[CSAuthenticationManager sharedManager] baseURL], self.mapID, query];
     if (parameters != nil) {
         [URLString appendString:@"?"];
@@ -77,7 +139,7 @@
             [URLString appendFormat:@"%@=%@", key, obj];
         }];
     }
-
+    
     NSURL *URL = [NSURL URLWithString:[URLString stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];
     NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:URL];
     
@@ -88,7 +150,7 @@
             [[[NSURLSession sharedSession] dataTaskWithRequest:request completionHandler:^(NSData * _Nullable data, NSURLResponse * _Nullable response, NSError * _Nullable error) {
                 
                 if ([(NSHTTPURLResponse *)response statusCode] == HTTP_401_NOT_AUTHORIZED) {
-
+                    
                     NSString *description = NSLocalizedString(INVALID_CREDINTIAL, @"");
                     NSError *responseError = [NSError errorWithDomain:NSCocoaErrorDomain code:kCFURLErrorUserCancelledAuthentication userInfo:@{NSLocalizedDescriptionKey: description}];
                     
@@ -127,7 +189,7 @@
 {
     NSMutableString *URLString = [NSMutableString stringWithFormat:@"%@/geocode/%@/%@,%@.json",
                                   [[CSAuthenticationManager sharedManager] baseURL], self.mapID, @(coordinate.latitude), @(coordinate.longitude)];
-
+    
     NSURL *URL = [NSURL URLWithString:[URLString stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];
     NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:URL];
     
@@ -182,7 +244,7 @@
     if (self != nil) {
         self.params = [NSMutableDictionary dictionary];
     }
-
+    
     return self;
 }
 
@@ -207,3 +269,24 @@
 }
 
 @end
+
+#pragma mark
+
+@implementation CSDistancePoints
+
+- (id)init
+{
+    self = [super init];
+    if (self != nil) {
+        self.pointsDesc = [NSMutableString string];
+    }
+    
+    return self;
+}
+
+- (void)addCoordinatePairWithDeparture:(CLLocationCoordinate2D)departure destination:(CLLocationCoordinate2D)destination {
+    
+    [self.pointsDesc appendString:[NSString stringWithFormat:@"%f,%f;%f,%f/", departure.latitude, departure.longitude, destination.latitude, destination.longitude]];
+}
+
+@end

README.md

-# CedarMap
+# CedarMaps
 
 ## Usage
 
@@ -37,9 +37,19 @@ or initialise a ``MGLMapView`` with the url:
 	- (void)forwardGeocodingWithQueryString:(NSString *)query parameters:(CSQueryParameters *)parameters completion:(void (^)(NSArray *results, NSError *error))completion;
 	- (void)reverseGeocodingWithCoordinate:(CLLocationCoordinate2D)coordinate completion:(void (^)(NSDictionary *result, NSError *error))completion;
 
+``CSMapKit`` has a method for getting distance between one pair or multiple pairs of points. First you create an instance of ``CSDistancePoints`` and use the following function to add points:
+
+	- (void)addCoordinatePairWithDeparture:(CLLocationCoordinate2D)departure destination:(CLLocationCoordinate2D)destination;
+
+This can be called multiple times. Then you can call the following method to get the distance info in an ``NSArray``:
+
+	- (void)distanceBetweenPoints:(CSDistancePoints *)points withCompletion:(void (^) (NSArray *results, NSError *error))completion;
+
+The results would be available once the request finishes loading in an array in the completion handler.
+
 In case you have got a credential error with ``nil`` as the result, there might be something wrong with your credentials at server side. So, before retrying and sending the request again request a new access token by calling method ``- (void)requestAccessTokenFromServer:(void (^)(NSString *token, NSError *error))completion;`` of ``CSAuthenticationManager`` class.
 
-Example projects for both ``Objective C`` and ``Swift`` are included.
+Example projects for both ``Objective-C`` and ``Swift`` are included.
 
 ## Requirements