Ensure media-library permissions when accessing media library

// FREEBIE

Signal/src/ViewControllers/AvatarViewHelper.m

@@ -1,5 +1,5 @@
 //
-//  Copyright (c) 2017 Open Whisper Systems. All rights reserved.
+//  Copyright (c) 2018 Open Whisper Systems. All rights reserved.
 //
 
 #import "AvatarViewHelper.h"
@@ -69,17 +69,22 @@ NS_ASSUME_NONNULL_BEGIN
     OWSAssertIsOnMainThread();
     OWSAssert(self.delegate);
 
-    UIImagePickerController *picker = [[UIImagePickerController alloc] init];
+    [self.delegate.fromViewController ows_askForCameraPermissions:^(BOOL granted) {
+        if (!granted) {
+            DDLogWarn(@"%@ Camera permission denied.", self.logTag);
+            return;
+        }
+
+        UIImagePickerController *picker = [UIImagePickerController new];
         picker.delegate = self;
         picker.allowsEditing = NO;
         picker.sourceType = UIImagePickerControllerSourceTypeCamera;
+        picker.mediaTypes = @[ (__bridge NSString *)kUTTypeImage ];
 
-    if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {
-        picker.mediaTypes = [[NSArray alloc] initWithObjects:(NSString *)kUTTypeImage, nil];
         [self.delegate.fromViewController presentViewController:picker
                                                        animated:YES
                                                      completion:[UIUtil modalCompletionBlock]];
-    }
+    }];
 }
 
 - (void)chooseFromLibrary
@@ -87,16 +92,21 @@ NS_ASSUME_NONNULL_BEGIN
     OWSAssertIsOnMainThread();
     OWSAssert(self.delegate);
 
-    UIImagePickerController *picker = [[UIImagePickerController alloc] init];
+    [self.delegate.fromViewController ows_askForMediaLibraryPermissions:^(BOOL granted) {
+        if (!granted) {
+            DDLogWarn(@"%@ Media Library permission denied.", self.logTag);
+            return;
+        }
+
+        UIImagePickerController *picker = [UIImagePickerController new];
         picker.delegate = self;
         picker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
+        picker.mediaTypes = @[ (__bridge NSString *)kUTTypeImage ];
 
-    if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary]) {
-        picker.mediaTypes = [[NSArray alloc] initWithObjects:(NSString *)kUTTypeImage, nil];
         [self.delegate.fromViewController presentViewController:picker
                                                        animated:YES
                                                      completion:[UIUtil modalCompletionBlock]];
-    }
+    }];
 }
 
 /*

Signal/src/ViewControllers/ContactsPicker.swift

@@ -1,5 +1,5 @@
 //
-//  Copyright (c) 2017 Open Whisper Systems. All rights reserved.
+//  Copyright (c) 2018 Open Whisper Systems. All rights reserved.
 //
 
 //  Originally based on EPContacts
@@ -161,7 +161,7 @@ open class ContactsPicker: OWSViewController, UITableViewDelegate, UITableViewDa
                 })
                 alert.addAction(cancelAction)
 
-                let settingsText = NSLocalizedString("OPEN_SETTINGS_BUTTON", comment:"Button text which opens the settings app")
+                let settingsText = CommonStrings.openSettingsButton
                 let openSettingsAction = UIAlertAction(title: settingsText, style: .default, handler: { (_) in
                     UIApplication.shared.openSystemSettings()
                 })

Signal/src/ViewControllers/ConversationView/ConversationViewController.m

@@ -2466,18 +2466,18 @@ typedef NS_ENUM(NSInteger, MessagesRangeSizeMode) {
 {
     [self ows_askForCameraPermissions:^(BOOL granted) {
         if (!granted) {
+            DDLogWarn(@"%@ camera permission denied.", self.logTag);
             return;
         }
-        UIImagePickerController *picker = [[UIImagePickerController alloc] init];
+
+        UIImagePickerController *picker = [UIImagePickerController new];
         picker.sourceType = UIImagePickerControllerSourceTypeCamera;
         picker.mediaTypes = @[ (__bridge NSString *)kUTTypeImage, (__bridge NSString *)kUTTypeMovie ];
         picker.allowsEditing = NO;
         picker.delegate = self;
 
-        dispatch_async(dispatch_get_main_queue(), ^{
         [self dismissKeyBoard];
         [self presentViewController:picker animated:YES completion:[UIUtil modalCompletionBlock]];
-        });
     }];
 }
 
@@ -2485,18 +2485,20 @@ typedef NS_ENUM(NSInteger, MessagesRangeSizeMode) {
 {
     OWSAssertIsOnMainThread();
 
-    if (![UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary]) {
+    [self ows_askForMediaLibraryPermissions:^(BOOL granted) {
-        DDLogError(@"PhotoLibrary ImagePicker source not available");
+        if (!granted) {
+            DDLogWarn(@"%@ Media Library permission denied.", self.logTag);
             return;
         }
 
-    UIImagePickerController *picker = [[UIImagePickerController alloc] init];
+        UIImagePickerController *picker = [UIImagePickerController new];
         picker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
         picker.delegate = self;
         picker.mediaTypes = @[ (__bridge NSString *)kUTTypeImage, (__bridge NSString *)kUTTypeMovie ];
 
         [self dismissKeyBoard];
         [self presentViewController:picker animated:YES completion:[UIUtil modalCompletionBlock]];
+    }];
 }
 
 /*

Signal/src/ViewControllers/HomeViewController.m

@@ -314,8 +314,8 @@ typedef NS_ENUM(NSInteger, CellState) { kArchiveState, kInboxState };
     imageEdgeInsets.top = round((kBarButtonSize - image.size.height) * 0.5f);
     imageEdgeInsets.bottom = round(kBarButtonSize - (image.size.height + imageEdgeInsets.top));
     button.imageEdgeInsets = imageEdgeInsets;
-    button.accessibilityLabel
+    button.accessibilityLabel = CommonStrings.openSettingsButton;
-        = NSLocalizedString(@"OPEN_SETTINGS_BUTTON", "Label for button which opens the settings UI");
+
     [button addTarget:self action:@selector(settingsButtonPressed:) forControlEvents:UIControlEventTouchUpInside];
     button.frame = CGRectMake(0,
         0,

Signal/src/util/UIViewController+Permissions.h

@@ -1,5 +1,5 @@
 //
-//  Copyright (c) 2017 Open Whisper Systems. All rights reserved.
+//  Copyright (c) 2018 Open Whisper Systems. All rights reserved.
 //
 
 #import <UIKit/UIKit.h>
@@ -9,7 +9,7 @@ NS_ASSUME_NONNULL_BEGIN
 @interface UIViewController (Permissions)
 
 - (void)ows_askForCameraPermissions:(void (^)(BOOL granted))callback;
-
+- (void)ows_askForMediaLibraryPermissions:(void (^)(BOOL granted))callbackParam;
 - (void)ows_askForMicrophonePermissions:(void (^)(BOOL granted))callback;
 
 @end

Signal/src/util/UIViewController+Permissions.m

@@ -1,10 +1,11 @@
 //
-//  Copyright (c) 2017 Open Whisper Systems. All rights reserved.
+//  Copyright (c) 2018 Open Whisper Systems. All rights reserved.
 //
 
 #import "Signal-Swift.h"
 #import "UIViewController+Permissions.h"
 #import <AVFoundation/AVFoundation.h>
+#import <Photos/Photos.h>
 #import <SignalMessaging/UIUtil.h>
 #import <SignalServiceKit/Threading.h>
 
@@ -42,10 +43,8 @@ NS_ASSUME_NONNULL_BEGIN
                              message:NSLocalizedString(@"MISSING_CAMERA_PERMISSION_MESSAGE", @"Alert body")
                       preferredStyle:UIAlertControllerStyleAlert];
 
-        NSString *settingsTitle
-            = NSLocalizedString(@"OPEN_SETTINGS_BUTTON", @"Button text which opens the settings app");
         UIAlertAction *openSettingsAction =
-            [UIAlertAction actionWithTitle:settingsTitle
+            [UIAlertAction actionWithTitle:CommonStrings.openSettingsButton
                                      style:UIAlertActionStyleDefault
                                    handler:^(UIAlertAction *_Nonnull action) {
                                        [[UIApplication sharedApplication] openSystemSettings];
@@ -72,6 +71,84 @@ NS_ASSUME_NONNULL_BEGIN
     }
 }
 
+- (void)ows_askForMediaLibraryPermissions:(void (^)(BOOL granted))callbackParam
+{
+    DDLogVerbose(@"[%@] ows_askForMediaLibraryPermissions", NSStringFromClass(self.class));
+
+    // Ensure callback is invoked on main thread.
+    void (^completionCallback)(BOOL) = ^(BOOL granted) {
+        DispatchMainThreadSafe(^{
+            callbackParam(granted);
+        });
+    };
+
+    void (^presentSettingsDialog)(void) = ^(void) {
+        UIAlertController *alert = [UIAlertController
+            alertControllerWithTitle:NSLocalizedString(@"MISSING_MEDIA_LIBRARY_PERMISSION_TITLE",
+                                         @"Alert title when user has previously denied media library access")
+                             message:NSLocalizedString(@"MISSING_MEDIA_LIBRARY_PERMISSION_MESSAGE",
+                                         @"Alert body when user has previously denied media library access")
+                      preferredStyle:UIAlertControllerStyleAlert];
+
+        UIAlertAction *openSettingsAction =
+            [UIAlertAction actionWithTitle:CommonStrings.openSettingsButton
+                                     style:UIAlertActionStyleDefault
+                                   handler:^(UIAlertAction *_Nonnull action) {
+                                       [[UIApplication sharedApplication] openSystemSettings];
+                                       completionCallback(NO);
+                                   }];
+        [alert addAction:openSettingsAction];
+
+        UIAlertAction *dismissAction = [UIAlertAction actionWithTitle:CommonStrings.dismissButton
+                                                                style:UIAlertActionStyleCancel
+                                                              handler:^(UIAlertAction *action) {
+                                                                  completionCallback(NO);
+                                                              }];
+        [alert addAction:dismissAction];
+
+        [self presentViewController:alert animated:YES completion:nil];
+    };
+
+    if ([UIApplication sharedApplication].applicationState == UIApplicationStateBackground) {
+        DDLogError(@"Skipping media library permissions request when app is in background.");
+        completionCallback(NO);
+        return;
+    }
+
+    if (![UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary]) {
+        DDLogError(@"%@ PhotoLibrary ImagePicker source not available", self.logTag);
+        completionCallback(NO);
+    }
+
+    PHAuthorizationStatus status = [PHPhotoLibrary authorizationStatus];
+
+    switch (status) {
+        case PHAuthorizationStatusAuthorized: {
+            completionCallback(YES);
+            return;
+        }
+        case PHAuthorizationStatusDenied: {
+            presentSettingsDialog();
+            return;
+        }
+        case PHAuthorizationStatusNotDetermined: {
+            [PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus newStatus) {
+                if (newStatus == PHAuthorizationStatusAuthorized) {
+                    completionCallback(YES);
+                } else {
+                    presentSettingsDialog();
+                }
+            }];
+            return;
+        }
+        case PHAuthorizationStatusRestricted: {
+            // when does this happen?
+            OWSFail(@"PHAuthorizationStatusRestricted");
+            return;
+        }
+    }
+}
+
 - (void)ows_askForMicrophonePermissions:(void (^)(BOOL granted))callbackParam
 {
     DDLogVerbose(@"[%@] ows_askForMicrophonePermissions", NSStringFromClass(self.class));

Signal/translations/en.lproj/Localizable.strings

@@ -1041,6 +1041,12 @@
    Alert title when camera is not authorized */
 "MISSING_CAMERA_PERMISSION_TITLE" = "Signal needs to access your camera.";
 
+/* Alert body when user has previously denied media library access */
+"MISSING_MEDIA_LIBRARY_PERMISSION_MESSAGE" = "You can grant this permission in the Settings app.";
+
+/* Alert title when user has previously denied media library access */
+"MISSING_MEDIA_LIBRARY_PERMISSION_TITLE" = "Signal Requires Access to your Media Library to do this.";
+
 /* notification title. Embeds {{caller's name or phone number}} */
 "MSGVIEW_MISSED_CALL_WITH_NAME" = "Missed call from %@.";
 
@@ -1146,8 +1152,7 @@
 /* No comment provided by engineer. */
 "OK" = "OK";
 
-/* Button text which opens the settings app
+/* Button text which opens the settings app */
-   Label for button which opens the settings UI */
 "OPEN_SETTINGS_BUTTON" = "Settings";
 
 /* Info Message when {{other user}} disables or doesn't support disappearing messages */

SignalMessaging/Views/ContactsViewHelper.m

@@ -1,5 +1,5 @@
 //
-//  Copyright (c) 2017 Open Whisper Systems. All rights reserved.
+//  Copyright (c) 2018 Open Whisper Systems. All rights reserved.
 //
 
 #import "ContactsViewHelper.h"
@@ -282,8 +282,7 @@ NS_ASSUME_NONNULL_BEGIN
                                            style:UIAlertActionStyleCancel
                                          handler:nil]];
 
-    [alertController addAction:[UIAlertAction actionWithTitle:NSLocalizedString(@"OPEN_SETTINGS_BUTTON",
+    [alertController addAction:[UIAlertAction actionWithTitle:CommonStrings.openSettingsButton
-                                                                  @"Button text which opens the settings app")
                                                         style:UIAlertActionStyleDefault
                                                       handler:^(UIAlertAction *_Nonnull action) {
                                                           [CurrentAppContext() openSystemSettings];

SignalMessaging/views/CommonStrings.swift

@@ -1,5 +1,5 @@
 //
-//  Copyright (c) 2017 Open Whisper Systems. All rights reserved.
+//  Copyright (c) 2018 Open Whisper Systems. All rights reserved.
 //
 
 import Foundation
@@ -15,6 +15,8 @@ import Foundation
     static public let cancelButton = NSLocalizedString("TXT_CANCEL_TITLE", comment:"Label for the cancel button in an alert or action sheet.")
     @objc
     static public let retryButton = NSLocalizedString("RETRY_BUTTON_TEXT", comment:"Generic text for button that retries whatever the last action was.")
+    @objc
+    static public let openSettingsButton = NSLocalizedString("OPEN_SETTINGS_BUTTON", comment: "Button text which opens the settings app")
 }
 
 @objc public class MessageStrings: NSObject {

SignalMessaging/views/OWSAlerts.swift

@@ -1,5 +1,5 @@
 //
-//  Copyright (c) 2017 Open Whisper Systems. All rights reserved.
+//  Copyright (c) 2018 Open Whisper Systems. All rights reserved.
 //
 
 import Foundation
@@ -14,7 +14,7 @@ import Foundation
         let alertMessage = NSLocalizedString("CALL_AUDIO_PERMISSION_MESSAGE", comment:"Alert message when calling and permissions for microphone are missing")
         let alertController = UIAlertController(title: alertTitle, message: alertMessage, preferredStyle: .alert)
         let dismissAction = UIAlertAction(title: CommonStrings.dismissButton, style: .cancel)
-        let settingsString = NSLocalizedString("OPEN_SETTINGS_BUTTON", comment: "Button text which opens the settings app")
+        let settingsString = CommonStrings.openSettingsButton
         let settingsAction = UIAlertAction(title: settingsString, style: .default) { _ in
             CurrentAppContext().openSystemSettings()
         }