[MC-1563] File downloading (#339)

* Adds CTFileDownloadManager class for file downloading
Adds callback for each file and all files download

* Added unit tests for CTFileDownloadManager

* Added unit tests for CTFileDownloadDelegate protocol callback methods.

* Updated callback approach to use completion block.
Updated unit tests.

* - Added class CTFileDownloader to handle file downloading from inapps, file variables.
- Added expiry logic for files downloaded.
- Added unit tests.

* Added public method to get file downloaded path.

* Added some unit tests for clearFileAssets method.

* - Added logic for handling url download in progress, only one request to the url to download the file.
- Added methods for image preloading cases.
- Added unit test cases.

* - Added thread safety check for updating active and inactive dictionary.
- Added changes for CS InApps to use the new CTFileDownloader class for image preloading.
- Removed previous usage of CTInAppImagePrefetchManager class for image preloading.

* Added callback for File variables only, and code cleanup.

* Address comments and improvements

* Rename methods

* Move duplicate methods to test helper

* Move tests to group

* Move tests headers and mocks to separate files

* Use longer resource timeout

* Improve tests

* Improve clear expired files

* Fix clear expired assets

* Save files to directory inside documents
Remove all files removes the files inside the directory
Add Unit tests

* Move to group

---------

Co-authored-by: Nikola Zagorchev <[email protected]>

CleverTapSDK/CTConstants.h

@@ -76,6 +76,13 @@ extern NSString *const kSessionId;
 #define CLTAP_NOTIFICATION_TAG @"W$"
 #define CLTAP_DATE_FORMAT @"yyyyMMdd"
 
+#pragma mark Constants for File Assets
+#define CLTAP_FILE_URLS_EXPIRY_DICT @"file_urls_expiry_dict"
+#define CLTAP_FILE_ASSETS_LAST_DELETED_TS @"cs_file_assets_last_deleted_timestamp"
+#define CLTAP_FILE_EXPIRY_OFFSET (60 * 60 * 24 * 7 * 2) // 2 weeks
+#define CLTAP_FILE_RESOURCE_TIME_OUT_INTERVAL 15
+#define CLTAP_FILES_DIRECTORY_NAME @"CleverTap_Files"
+
 #pragma mark Constants for App fields
 #define CLTAP_APP_VERSION @"Version"
 #define CLTAP_LATITUDE @"Latitude"

CleverTapSDK/CTInAppNotification.h

@@ -3,7 +3,7 @@
 #import "CTInAppUtils.h"
 #import "CTNotificationButton.h"
 #if !CLEVERTAP_NO_INAPP_SUPPORT
-#import "CTInAppImagePrefetchManager.h"
+#import "CTFileDownloader.h"
 #endif
 
 @interface CTInAppNotification : NSObject
@@ -66,7 +66,7 @@
 - (instancetype)init __unavailable;
 #if !CLEVERTAP_NO_INAPP_SUPPORT
 - (instancetype)initWithJSON:(NSDictionary*)json
-        imagePrefetchManager:(CTInAppImagePrefetchManager *)imagePrefetchManager;
+              fileDownloader:(CTFileDownloader *)fileDownloader;
 #endif
 
 - (void)prepareWithCompletionHandler: (void (^)(void))completionHandler;

CleverTapSDK/CTInAppNotification.m

@@ -66,7 +66,7 @@ @interface CTInAppNotification() {
 
 @property (nonatomic, readwrite) NSString *error;
 
-@property (nonatomic, strong) CTInAppImagePrefetchManager *imagePrefetchManager;
+@property (nonatomic, strong) CTFileDownloader *fileDownloader;
 
 @end
 
@@ -78,10 +78,10 @@ @implementation CTInAppNotification: NSObject
 @synthesize mediaIsVideo=_mediaIsVideo;
 
 - (instancetype)initWithJSON:(NSDictionary *)jsonObject
-        imagePrefetchManager:(CTInAppImagePrefetchManager *)imagePrefetchManager {
+              fileDownloader:(CTFileDownloader *)fileDownloader {
     if (self = [super init]) {
         @try {
-            self.imagePrefetchManager = imagePrefetchManager;
+            self.fileDownloader = fileDownloader;
             self.inAppType = CTInAppTypeUnknown;
             self.jsonDescription = jsonObject;
             self.campaignId = (NSString*) jsonObject[CLTAP_NOTIFICATION_ID_TAG];
@@ -434,7 +434,7 @@ - (BOOL)isKeyValidInDictionary:(NSDictionary *)d forKey:(NSString *)key ofClass:
 
 - (UIImage *)loadImageIfPresentInDiskCache:(NSURL *)imageURL {
     NSString *imageURLString = [imageURL absoluteString];
-    UIImage *image = [self.imagePrefetchManager loadImageFromDisk:imageURLString];
+    UIImage *image = [self.fileDownloader loadImageFromDisk:imageURLString];
     if (image) return image;
     return nil;
 }

CleverTapSDK/CleverTap.m

@@ -31,6 +31,7 @@
 #import "CTDispatchQueueManager.h"
 #import "CTMultiDelegateManager.h"
 #import "CTSessionManager.h"
+#import "CTFileDownloader.h"
 
 #if !CLEVERTAP_NO_INAPP_SUPPORT
 #import "CTInAppFCManager.h"
@@ -56,7 +57,6 @@
 #import "CleverTap+InAppsResponseHandler.h"
 #import "CTInAppEvaluationManager.h"
 #import "CTInAppTriggerManager.h"
-#import "CTInAppImagePrefetchManager.h"
 #endif
 
 #if !CLEVERTAP_NO_INBOX_SUPPORT
@@ -242,7 +242,7 @@ @interface CleverTap () <UIApplicationDelegate> {
 @property (nonatomic, strong, readwrite) CTInAppEvaluationManager *inAppEvaluationManager;
 @property (nonatomic, strong, readwrite) CTInAppDisplayManager *inAppDisplayManager;
 @property (nonatomic, strong, readwrite) CTImpressionManager *impressionManager;
-@property (nonatomic, strong, readwrite) CTInAppImagePrefetchManager *imagePrefetchManager;
+@property (nonatomic, strong, readwrite) CTFileDownloader *fileDownloader;
 @property (nonatomic, strong, readwrite) CTInAppStore * _Nullable inAppStore;
 #endif
 
@@ -477,6 +477,8 @@ - (instancetype)initWithConfig:(CleverTapInstanceConfig*)config andCleverTapID:(
         [self initNetworking];
         [self inflateQueuesAsync];
         [self addObservers];
+
+        self.fileDownloader = [[CTFileDownloader alloc] initWithConfig:self.config];
 #if !CLEVERTAP_NO_INAPP_SUPPORT
         if (!_config.analyticsOnly && ![CTUIUtils runningInsideAppExtension]) {
             [self initializeInAppSupport];
@@ -506,12 +508,9 @@ - (instancetype)initWithConfig:(CleverTapInstanceConfig*)config andCleverTapID:(
 
 #if !CLEVERTAP_NO_INAPP_SUPPORT
 - (void)initializeInAppSupport {
-    CTInAppImagePrefetchManager *imagePrefetchManager = [[CTInAppImagePrefetchManager alloc] initWithConfig:self.config];
-    self.imagePrefetchManager = imagePrefetchManager;
-
     CTInAppStore *inAppStore = [[CTInAppStore alloc] initWithConfig:self.config
                                                     delegateManager:self.delegateManager
-                                               imagePrefetchManager:self.imagePrefetchManager
+                                                     fileDownloader:self.fileDownloader
                                                            deviceId:self.deviceInfo.deviceId];
     self.inAppStore = inAppStore;
 
@@ -525,7 +524,7 @@ - (void)initializeInAppSupport {
                                                                               inAppFCManager:inAppFCManager
                                                                            impressionManager:impressionManager
                                                                                   inAppStore:inAppStore
-                                                                        imagePrefetchManager:self.imagePrefetchManager];
+                                                                              fileDownloader:self.fileDownloader];
 
     CTInAppEvaluationManager *evaluationManager = [[CTInAppEvaluationManager alloc] initWithAccountId:self.config.accountId deviceId:self.deviceInfo.deviceId delegateManager:self.delegateManager impressionManager:impressionManager inAppDisplayManager:displayManager inAppStore:inAppStore inAppTriggerManager:triggerManager];
 
@@ -1563,7 +1562,7 @@ - (void)resumeInAppNotifications {
 }
 
 - (void)clearInAppResources:(BOOL)expiredOnly {
-    [self.imagePrefetchManager _clearImageAssets:expiredOnly];
+    [self.fileDownloader clearFileAssets:expiredOnly];
 }
 #endif
 

CleverTapSDK/FileDownload/CTFileDownloadManager.h

@@ -0,0 +1,68 @@
+#import <Foundation/Foundation.h>
+
+@class CleverTapInstanceConfig;
+
+NS_ASSUME_NONNULL_BEGIN
+
+typedef void(^CTFilesDownloadCompletedBlock)(NSDictionary<NSString *, NSNumber *> *status);
+typedef void(^CTFilesDeleteCompletedBlock)(NSDictionary<NSString *, NSNumber *> *status);
+typedef void(^CTFilesRemoveCompletedBlock)(NSDictionary<NSString *, NSNumber *> *status);
+typedef void (^DownloadCompletionHandler)(NSURL *url, BOOL success);
+
+@interface CTFileDownloadManager : NSObject
+
++ (instancetype)sharedInstanceWithConfig:(CleverTapInstanceConfig *)config;
+- (instancetype)init NS_UNAVAILABLE;
+
+/*!
+ @method
+ 
+ @discussion
+ This method accepts file urls as NSArray of NSURLs and downloads each file to directory inside NSDocumentDirectory directory.
+ 
+ @param completion the completion block to be executed when all files are downloaded. `status` dictionary will
+                    contain file download status of each file as {url,success}. The completion block is executed on background queue.
+ */
+- (void)downloadFiles:(NSArray<NSURL *> *)urls withCompletionBlock:(CTFilesDownloadCompletedBlock)completion;
+
+/*!
+ @method
+ 
+ @discussion
+ This method checks if file is already present in the directory or not.
+ */
+- (BOOL)isFileAlreadyPresent:(NSURL *)url;
+
+/*!
+ @method
+ 
+ @discussion
+ This method returns the file path to the file. This method does *not* check if the file exists.
+ */
+- (NSString *)filePath:(NSURL *)url;
+
+/*!
+ @method
+ 
+ @discussion
+ This method deletes the files from the directory if present.
+ 
+ @param completion the completion block to be executed when all files are deleted. `status` dictionary will
+                    contain file delete status of each file as {url,success}. The completion block is executed on background queue.
+ */
+- (void)deleteFiles:(NSArray<NSString *> *)urls withCompletionBlock:(CTFilesDeleteCompletedBlock)completion;
+
+/*!
+ @method
+ 
+ @discussion
+ This method deletes all files from the directory.
+ 
+ @param completion the completion block to be executed when all files are deleted. `status` dictionary will
+                    contain file download status of each file as {file path,success}. The completion block is executed on background queue.
+ */
+- (void)removeAllFilesWithCompletionBlock:(CTFilesRemoveCompletedBlock)completion;
+
+@end
+
+NS_ASSUME_NONNULL_END